IPAC2016 - List of Keywords (vacuum)

Paper	Title	Other Keywords	Page
MOYAA01	Commissioning of the MAX IV Light Source	storage-ring, emittance, injection, lattice	11
	M. Eriksson, E. Al-Dmour, Å. Andersson, M.A.G. Johansson, S.C. Leemann, L. Malmgren, P.F. Tavares, S. Thorin MAX IV Laboratory, Lund University, Lund, Sweden
	This presentation reports on the beam commissioning status of MAX IV, experience gained and lessons learned, as well as future plans.
	Slides MOYAA01 [6.682 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOYAA01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB006	First Tests of SuperKEKB Luminosity Monitors during 2016 Single Beam Commissioning	luminosity, simulation, scattering, background	81
	D. El Khechen, P. Bambade, A. Blin, P. Cornebise, D. Jehanno, V. Kubytskyi, Y. Peinaud, C. Rimbault LAL, Orsay, France Y. Funakoshi, Y. Ohnishi, S. Uehara KEK, Ibaraki, Japan
	The SuperKEKB e⁺e⁻ collider aims to reach a very high luminosity of 8 10³⁵ cm^-2s⁻¹, using highly focused ultra-low emittance bunches colliding every 4ns. Fast luminosity monitoring is required for luminosity feedback and optimisation in presence of dynamic imperfections. The aimed relative precision is about 10^-3 in 1ms, which can be in principle achieved thanks to the very large cross-section of the radiative Bhabha process at zero degree scattering angle. Diamond, Cherenkov and scintillator sensors are to be placed just outside the beam pipe, downstream of the interaction point in both rings, at locations with event rates consistent with the aimed precision and small enough backgrounds from single-beam particle losses. The initial configuration installed for the 2016 "phase 1" single beam commissioning will be described, including the sensors, mechanical setup, readout electronics and first stage DAQ. Preliminary measurements and analysis of beam gas Bremsstrahlung loss data collected with the luminosity monitors will be reported and compared with a detailed simulation, for several experimental conditions during the SuperKEKB commissioning.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB006
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB008	Modeling and Experimental Studies of Beam Halo at ATF2	scattering, coupling, damping, optics	88
	R.J. Yang, P. Bambade, V. Kubytskyi LAL, Orsay, France A. Faus-Golfe, N. Fuster-Martínez IFIC, Valencia, Spain T. Naito KEK, Ibaraki, Japan
	The Accelerator Test Facility 2 (ATF2) at KEK is a prototype of the final focus system for the next generation of Future Linear Colliders(FCL). It aims to focus the beams to tens of nanometer transverse sizes and to provide stability at the few nm level. Achieving these goals requires modelling, measuring and suppressing of the transverse beam halo before the interaction point (IP). This paper presents a beam tail/halo generator based on realistic model and the investigation of vertical and horizontal beam tail/halo distribution at ATF2.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB008
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB011	ROSE, Measuring the Full 4D Transverse Beam Matrix of Ion Beams	emittance, ion, coupling, detector	98
	M.T. Maier, X. Du, P. Gerhard, L. Groening, S. Mickat, H. Vormann, C. Xiao GSI, Darmstadt, Germany
	A ROtating System for Emittance measurements ROSE, to measure the full 4 dimensional transverse beam matrix of an ion beam has been developed and commissioned. Different ion beams behind the HLI at GSI have been used in two commissioning beam times. All technical aspects of ROSE have been tested, ROSE has been benchmarked against existing emittance scanners for horizontal and vertical projections, and the method, hard-, and software to measure the 4D beam matrix has been upgraded, refined, and successfully commissioned. The inter plane correlations of the HLI beam have been measured, yet as no significant initial correlations were found to be present, controlled coupling of the beam by using a skew triplet has been applied and confirmed with ROSE. The next step is to use ROSE to measure and remove the known inter plane correlations of a uranium beam before SIS18 injection.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB011
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB012	A High-Energy-Scrapersystem for the S-DALINAC Extraction - Design and Installation	electron, extraction, linac, dipole	101
	L.E. Jürgensen, T. Bahlo, C. Burandt, T. Kürzeder, N. Pietralla, S. Weih, J. Wissmann TU Darmstadt, Darmstadt, Germany F. Hug IKP, Mainz, Germany
	Funding: *Funded by Deutsche Forschungsgemeinschaft under grant No. SFB 634 The superconducting Darmstadt linear electron accelerator (S-DALINAC) of the Institute for Nuclear Physics at Technische Universität Darmstadt delivers electron beams in cw-mode with energies up to 130 MeV. The accelerator consists of a 10-MeV injector and a 30-MeV main linac where superconducting 3-GHz microwave cavities are operated at a temperature of 2 K for beam acceleration. With three recirculation beamlines the main linac can be used up to four times. To improve the energy spread and the energy stability of the beam a new scrapersystem has been developed and installed. It changes the extraction beam line into a dispersion-conserving chicane consisting of four dipole magnets and three scrapers. The system includes scraping of x- and y-halo in two positions as well as improving and stabilizing energy spread on a dispersive part. We will present the design of the system and report on its installation into the accelerator complex.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB012
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB022	Conceptual Design for SR Monitor in the FCC Beam Emittance (Size) Diagnostic	extraction, diagnostics, emittance, brightness	133
	T.M. Mitsuhashi, K. Oide KEK, Ibaraki, Japan F. Zimmermann CERN, Geneva, Switzerland
	A conceptual design for emittance diagnostics through a beam size measurement using the synchrotron radiation (SR) is studied for the FCC. For the FCC-ee, a X-ray interferometer is propose to measure a nano-radian order vertical beam size. Also conceptual design of SR monitor is studied for FCC-hh. In the FCC-hh, visible SR will emitted from bending magnet in the energy range from the injection (3TeV) to top energy (50TeV). Hard X-ray SR will only available in the energy upper than 30TeV. The various instrumentations using the visible SR is usable for all energy range. Around the top energy, the X-ray pinhole camera will convenient for beam diagnostics of emittance through the beam size measurement.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB022
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB024	Electron Cloud Measurements at J-PARC Main Ring	electron, detector, proton, extraction	137
	B. Yee-Rendón, H. Kuboki, R. Muto, K. Satou, M. Tomizawa, T. Toyama, M. Uota KEK, Ibaraki, Japan
	Electron cloud instability is presented in most of the high intensity proton rings. During the Slow beam extraction (SX) mode at Main Ring of J-PARC, signals related with its formation were observed. An electron cloud detector is installed downstream of the ElectroStatic Septum (ESS), to measure the electron signal. Additionally, scintillation detector with photomultiplier, a proportional counter and photo-diode were set closely to the electron cloud detector to observe the beam lost. This paper presents the measurements of the electron cloud and some of the conditions which support its creation, for instance the signal of lost particle from the beam loss monitors, the residual gas in the vacuum duct by using vacuum pressure gauges, etc.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB024
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB026	Frequency and Time Domain Measurement of Coherent Transition Radiation	electron, laser, radiation, polarization	143
	K. Kan, M. Gohdo, T. Kondoh, I. Nozawa, J. Yang, Y. Yoshida ISIR, Osaka, Japan
	Ultrashort electron beams are essential for light sources and time-resolved measurements. Electron beams can emit terahertz (THz) pulses using coherent transition radiation (CTR). Michelson interferometer is one of can-didates for analyzing the pulse width of an electron beam based on frequency-domain analysis. Recently, electron beam measurement using a photoconductive antenna (PCA) based on time-domain analysis has been investi-gated. In this paper, to improve beam diagnostics of ul-trashort electron beam, investigation of characteristics of a PCA for generation and frequency and time-domain measurement of THz pulses was conducted. * I. Nozawa et al., Phys. Rev. ST Accel. Beams 17, 072803 (2014). ** K. Kan et al., Appl. Phys. Lett. 102, 221118 (2013).
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB026
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB029	Development Status of Linear Focal Cherenkov Ring Camera	electron, laser, photon, experiment	152
	K. Nanbu, T. Abe, H. Hama, F. Hinode, S. Kashiwagi, T. Muto, I. Nagasawa, H. Saito, K. Takahashi, C. Tokoku Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
	Linear focal Cherenkov ring camera (LFC-Camera) has been developed for single shot measurement of longitudinal phase space distribution of quasi-relativistic electron beam, where the electron's velocity still depends on its energy. The LFC-camera employs velocity dependence of opening angle of Cherenkov light produced by electron beam to observe its energy (momentum) distribution. Since the Cherenkov light contains the time information if the radiator medium is thin enough, we can get the longitudinal phase space distribution measuring both time and energy spectra simultaneously using a streak camera. We employ a thin silica aerogel with water-free hydrophobic treatment as Cherenkov radiator. We have evaluated characteristics of the silica aerogel radiator, and demonstration of the LFC-camera at a beam diagnosis section of t-ATCS is being proceeded.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB029
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB039	Design of Bunch Length Measurement System at the IRFEL Using a Martin-Puplett Interferometer	radiation, electron, detector, polarization	178
	T.Y. Zhou, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, F.F. Wu, Y.L. Yang, Z.R. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Supported by the National Science Foundation of China (11575181, 11175173) Electron bunch length measurement is of great significance for optimizing IRFEL performance. An optical autocorrelation system using coherent transition radiation (CTR) would be set up to measure the electron bunch length at the IRFEL. CTR can be occurred when short electron bunches traverse a vacuum-metal interface. A Martin-Puplett interferometer allowed measurement of the autocorrelation of the CTR signal. The basic principle and the main components of Martin-Puplett interferometer are elaborated in this paper.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB039
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB042	Design and Simulation of Button Beam Position Monitor for IR-FEL*	FEL, simulation, electron, electronics	187
	X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, F.F. Wu, Y.L. Yang, T.Y. Zhou, Z.R. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: * Supported by the National Science Foundation of China (11575181, 11175173) A new button-type beam position monitor(BPM) was designed for the IR-FEL project. Firstly, the longitudinal size of BPM needs to be short enough to save space because the entire machine of IR-FEL is very compact. And in the matter of installation problem, all four electrodes are deviated 30 degrees from the horizontal axis. Then, according to these two limited conditions and beam parameters, we builded up a simple model and did some simulated calculations to ensure a good performance of position resolution, which should be better than 50μm. The simulations include an estimation of induced signals in both time and frequency domains, horizontal and vertical sensitivities, mapping figures and so on. This button BPM will be manufactured in the near future and then we can do some off-line experiments to test it. # Corresponding author (email: bgsun@ustc.edu.cn)
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB042
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB043	Preliminary Research of HLS II BLM System	storage-ring, detector, operation, site	190
	F.F. Wu, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, J.G. Wang, Y.L. Yang, Z.R. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China Y.K. Chen IHEP, Beijing, People's Republic of China
	Beam loss monitor system has been designed in many electron storages in order to indirectly measure lost electrons, which can be used to analysis beam loss mechanism and beam life. It can contribute to beam commissioning and improving stable operation of storage ring. According to lattice structure of the HLS II storage ring, 64 beam loss detectors have been located in the upper, lower, inner, outer side surfaces of vacuum chamber in the HLS II storage ring. Some preliminary researches based on the HLS II BLM system have been done. The results in successfully stable operation and unsuccessfully stable operation in beam commissioning stage were compared. Analysis of a sudden lost beam phenomenon were carried out.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB043
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR019	Beam Tests of a Prototype Stripline Beam Position Monitoring System for the Drive Beam of the CLIC Two-beam Module at CTF3	electronics, pick-up, impedance, operation	270
	A. Benot-Morell, A. Faus-Golfe IFIC, Valencia, Spain A. Benot-Morell, M. Wendt CERN, Geneva, Switzerland A. Faus-Golfe LAL, Orsay, France J.M. Nappa, S. Vilalte IN2P3-LAPP, Annecy-le-Vieux, France
	Funding: MINECO contract no. FPA2013-47883-C2-1-P. CLIC Collaboration Agreement, contract no. KE2638/BE. FNRA contract no. ANR-11-IDEX-0003-02. In collaboration with LAPP and IFIC, two units of a prototype stripline Beam Position Monitor (BPM) for the CLIC Drive Beam (DB), and its associated readout electronics have been successfully installed and tested in the Two-Beam-Module (TBM) at the CLIC Test Facility 3 (CTF3) at CERN. This paper gives a short overview of the BPM system and presents the performance measured under different Drive Beam configurations.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR023	Surface Characterization and Field Emission Measurements of Copper Samples inside a Scanning Electron Microscope	electron, controls, experiment, radio-frequency	283
	J. Ögren, V.G. Ziemann Uppsala University, Uppsala, Sweden S.H.M. Jafri, K. Leifer Uppsala University, Department of Engineering Sciences, Uppsala, Sweden
	Vacuum breakdown in normal-conducting accelerating structures is a limiting factor for high gradient acceleration. Many aspects of the physics governing the breakdown process and its onset are yet to be fully understood. At Uppsala University we address these questions with an in-situ experimental setup mounted in an environmental scanning electron microscope. It consists of a piezo motor driven tungsten needle and a sample surface mounted on a piezo stage, allowing for nano-meter 3D-position control. One of the piezo motors controls the needle-sample gap while the two other scan across the surface. A DC-voltage up to 1 kV is applied across the gap and field emission currents from a copper surface are measured with an electrometer. Here we present the setup and some initial results.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR023
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR027	Employing Beam-Gas Interaction Vertices for Transverse Profile Measurements	detector, emittance, luminosity, real-time	296
	M.N. Rihl, A. Alexopoulos, V. Baglin, C. Barschel, E. Bravin, G. Bregliozzi, N. Chritin, B. Dehning, M. Ferro-Luzzi, C. Gaspar, M. Giovannozzi, R. Jacobsson, L.K. Jensen, O.R. Jones, N.J. Jurado, V. Kain, M. Kuhn, B. Luthi, P. Magagnin, R. Matev, N. Neufeld, J. Panman, V. Salustino Guimaraes, B. Salvant, R. Veness, S. Vlachos CERN, Geneva, Switzerland A. Bay, F. Blanc, S. Gianì, G.J. Haefeli, P. Hopchev, T. Nakada, B. Rakotomiaramanana, O. Schneider, M. Tobin, Q.D. Veyrat, Z. Xu EPFL, Lausanne, Switzerland R. Greim, W. Karpinski, T. Kirn, S. Schael, G. Schwering, M. Wlochal, A. von Dratzig RWTH, Aachen, Germany
	Interactions of high-energy beam particles with residual gas offer a unique opportunity to measure the beam profile in a non-intrusive fashion. Such a method was successfully pioneered* at the LHCb experiment using a silicon microstrip vertex detector. During the recent Large Hadron Collider shutdown at CERN, a demonstrator Beam-Gas Vertexing system based on eight scintillating-fibre modules was designed*, constructed and installed on Ring 2 to be operated as a pure beam diagnostics device. The detector signals are read out and collected with LHCb-type front-end electronics and a DAQ system consisting of a CPU farm. Tracks and vertices will be reconstructed to obtain a beam profile in real time. Here, first commissioning results are reported. The advantages and potential for future applications of this technique are discussed. LHCb collaboration, Journal of Instrumentation, 9, P12005 ** P. Hopchev in Proc. of IPAC 2014, June 15-20, 2014, Dresden Germany
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR027
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR046	Characterizing Supersonic Gas Jet-based Beam Profile Monitors	ion, simulation, diagnostics, electron	357
	H.D. Zhang, A.S. Alexandrova, A. Jeff, V. Tzoganis, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom A.S. Alexandrova, A. Jeff, V. Tzoganis, C.P. Welsch, H.D. Zhang The University of Liverpool, Liverpool, United Kingdom A. Jeff CERN, Geneva, Switzerland
	Funding: Work supported by EU under contracts 215080 and 289191, Helmholtz Association (VH-NG-328) and STFC under the Cockcroft Institute core grant ST/G008248/1. The next generation of high power, high intensity accelerators requires non-invasive diagnostics, particularly beam profile monitors. Residual gas-based diagnostics such as ionization beam profile or beam induced fluorescence monitors have been used to replace commonly used scintillating screens. At the Cockcroft Institute an alternative technique using a supersonic gas jet, shaped into a 45o curtain screen, was developed. It has already demonstrated its superior performance in terms of resolution and signal-to-noise ratio in comparison with residual gas monitors in experimental studies. The performance of this type of monitor depends on the achievable jet homogeneity and quality. Using a movable vacuum gauge as a scanner, the dynamic characteristics of the jet are studied. In this paper we also give an analysis of the resolution for this monitor in detail from the theory and ion drift simulation.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR046
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR052	Single-shot Bunch-by-Bunch Horizontal Beam Size Measurements using a Gated Camera at CesrTA	electron, positron, ion, synchrotron-radiation	364
	S. Wang Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA R. Holtzapple CalPoly, San Luis Obispo, California, USA
	Funding: Work supported by NSF NSF PHY-1416318, PHYS-1068662, PHYS-1535696 A visible-light beam size monitor has been built and commissioned to measure transverse beam profiles at CESR-TA. In order to eliminate beam jitter and to study bunch-by-bunch beam dynamics, a fast-gating camera has been utilized to measure single bunch transverse beam profiles. The minimum camera gate width is ~ 3ns which allows us to resolve single bunch beam dynamics along a CesrTA bunch train. Using single bunch interferometry at different bunch currents, we found that the horizontal beam sizes measured by gated camera are consistently less than those measured by a conventional CCD camera, demonstrating the elimination of turn-by-turn beam jitter with single shot capability. By stepping the camera trigger delay, we collected transverse beam profile images from each bunch in a 14ns-spacing 30-bunch train. The horizontal motion of each bunch as well as the horizontal beam size increases dramatically along an electron train but not along positron bunch trains under the same machine condition. The difference in single bunch horizontal dynamics may be a signature for the difference between electron cloud build-up for positron bunch trains versus ions present for electron bunch trains. S.T. Wang, D.L. Rubin, J. Conway, M. Palmer, D. Hartill, R. Campbell, R. Holtzapple, NIMA, 703 (2013) 80
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR052
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR056	Single-shot THz Spectrometer for Measurement of RF Breakdown in mm-wave Accelerators	detector, radiation, alignment, laser	374
	S.V. Kutsaev, A.Y. Murokh, M. Ruelas, E.A. Savin, H.L. To RadiaBeam Systems, Santa Monica, California, USA M. Dal Forno, V.A. Dolgashev SLAC, Menlo Park, California, USA V. Goncharik Logicware Inc, New York, USA E.A. Savin MEPhI, Moscow, Russia
	Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics, under contract DE-SC0013684 We present a new instrument designed to detect RF pulse shortening caused by vacuum RF breakdown in mm-wave particle accelerators. RF breakdown limits the performance of high gradient RF accelerators. To understand the properties of these breakdowns, it is necessary to have diagnostics that reliably detect RF breakdowns. In X-band or S-band accelerators, RF breakdowns are detected by measuring RF pulse shortening, vacuum burst, or, if current monitors are available, spikes in the field-emitted currents. In mm-wave accelerators, all of these methods are difficult to use. In our experiments, we could not measure RF pulse shortening directly with a crystal detector because the RF pulse is very short'just a few nanoseconds'and changes in the measured signal were masked by RF amplitude jitter. To overcome this limitation, we built a single-shot spectrometer with a frequency range of 117-125 GHz and a resolution of 0.1 GHz. The spectrometer should be able to measure the widening of the spectrum caused by the shortening of nanosecond-long pulses. We present design considerations, first experimental results obtained at FACET, and planned future improvements for the spectrometer.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR056
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR059	Development of S-band High Power Load	klystron, radio-frequency, radiation, electron	383
	X.C. Meng, H.B. Chen, C. Cheng, Y.-C. Du, Q. Gao, J. Shi, P. Wang, Z.F. Xiong TUB, Beijing, People's Republic of China
	Several types of S-band high power loads have been designed, manufactured and tested successfully in Tsinghua University. The high power loads, which work at 2856 MHz for 10 MW~100 MW range, are made of all stainless steel. In this paper, we will present the design, fabrication and the high power test results.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR059
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR060	C-Band Deflecting Cavity for Bunch Length Measurement of 2.5 MeV Electron Beam	cavity, electromagnetic-fields, coupling, simulation	386
	J. Jiang, H.B. Chen, J. Shi, P. Wang, L. Zhang, S.X. Zheng TUB, Beijing, People's Republic of China
	The C-band deflecting cavity designed last year is finished. In this paper, the RF measurement of the cavity is introduced. After tuning, it works well at 5.712GHz with a coupling factor degree around 1.05. And we measured the electromagnetic field with bead-pull method. The flatness of the magnetic field is around 0.9, which is not ideal but meet the requirements of the bunch length measurement. And we propose a method of tuning to make sure both frequency and field flatness.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR060
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW004	Realization and High Power Tests of Damped C-Band Accelerating Structures for the ELI-NP Linac	ion, HOM, klystron, damping	399
	D. Alesini, M. Bellaveglia, S. Bini, R. Boni, P. Chimenti, F. Cioeta, R.D. Di Raddo, A. Falone, A. Gallo, V.L. Lollo, L. Palumbo, S. Pioli, A. Variola INFN/LNF, Frascati (Roma), Italy F. Cardelli, M. Magi, A. Mostacci, L. Palumbo, L. Piersanti University of Rome La Sapienza, Rome, Italy F. Cardelli, L. Piersanti INFN-Roma1, Rome, Italy P. Favaron, F. Poletto INFN/LNL, Legnaro (PD), Italy L. Ficcadenti, F. Pellegrino, V. Pettinacci INFN-Roma, Roma, Italy
	The ELI-NP C-Band structures are 1.8 m long travelling wave accelerating structures, quasi-constant gradient, with a field phase advance per cell of 2pi/3. They operate at a repetition rate of 100 Hz and, because of the multi-bunch operation, they have been designed with a dipole HOM damping system to avoid beam break-up (BBU). The structures have symmetric input and output couplers and integrate, in each cell, a waveguide HOM damping systems with silicon carbide RF absorbers. An optimization of the electromagnetic and mechanical design has been done to simplify the fabrication and to reduce their cost. After the first full scale prototype successfully tested at the nominal gradient of 33 MV/m, the production of the twelve structures started. In the paper we illustrate the main design criteria, the realization process and the high power test results.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW004
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW005	Design of Linac with the New Gaskets Clamping Fabrication Technique	coupling, impedance, linac, gun	403
	F. Cardelli INFN-Roma1, Rome, Italy D. Alesini INFN/LNF, Frascati (Roma), Italy M. Magi, L. Palumbo University of Rome La Sapienza, Rome, Italy F. Pellegrino, V. Pettinacci INFN-Roma, Roma, Italy
	Recently, a new technique for the realization of high gradient accelerating structures based on the use of gaskets without brazing processes, has been successfully tested at high power on a 1.6 cells RF gun (D. Alesini, et al, PRST 18, 02001, 2015). The new technique developed at the Laboratories of Frascati of the INFN (Italy) in the framework of the SPARC_LAB project has been also adopted for the ELI-NP RF gun. The use of the special gaskets that simultaneously guarantee the vacuum seal and a perfect RF contact allow to avoid the brazing process, strongly reducing the cost, the realization time and the risk of failure. Moreover, without copper annealing due to the brazing process, it is possible, in principle, to decrease the breakdown rate increasing, at the same time, the maximum achievable gradient. The extension of this new fabrication process to complex LINAC structures is the next step on the application of this new technique on particle accelerator. In the paper, we discuss how to extend this process to S-band and C-band Travelling Wave accelerating structures illustrating their electromagnetic design and their mechanical realization.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW005
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW007	On the Calibration Measurement of Stripline Beam Position Monitor for the ELI-NP Facility	simulation, linac, electromagnetic-fields, impedance	411
	D. De Arcangelis, F. Cardelli, A. Mostacci, L. Palumbo University of Rome La Sapienza, Rome, Italy
	Stripline Beam Position Monitor (BPM) will be installed in the Compton Gamma Source in construction at the ELI Nuclear Physics facility in Romania. A test bench for the calibration of BPM has been built to characterize the device with stretched wire measurement in order to get the BPM response map. A full S-parameters characterisation is performed as well to measure the electrical offset with the "Lambertson method". This paper discusses the extensive simulations performed with full 3D electromagnetic CAD codes of the above measurements to investigate measurement accuracy, possible measurement artefacts and the beam position reconstruction.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW007
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW025	Vacuum RF Breakdown of Accelerating Cavities in Multi-Tesla Magnetic Fields	cavity, operation, Windows, electron	444
	D.L. Bowring, A. Moretti, M.A. Palmer, D.W. Peterson, A.V. Tollestrup, K. Yonehara Fermilab, Batavia, Illinois, USA B.T. Freemire IIT, Chicago, Illinois, USA A.V. Kochemirovskiy University of Chicago, Chicago, Illinois, USA P.G. Lane, Y. Torun Illinois Institute of Technology, Chicago, Illinois, USA
	Funding: Work supported by Fermilab Research Alliance, LLC under Contract No. DE-AC02-07CH11359. Ionization cooling of intense muon beams requires the operation of high-gradient, normal-conducting RF structures within multi-Tesla magnetic fields. The application of strong magnetic fields has been shown to lead to an increase in vacuum RF breakdown. This phenomenon imposes operational (i.e. gradient) limitations on cavities in ionization cooling channels, and has a bearing on the design and operation of other RF structures as well, such as photocathodes and klystrons. We present recent results from Fermilab's MuCool Test Area (MTA), in which 201 and 805 MHz cavities were operated at high power both with and without the presence of multi-Tesla magnetic fields. We present an analysis of damage due to breakdown in these cavities, as well as measurements related to dark current and their relation to a conceptual model describing breakdown phenomena.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW025
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW028	Progress on the MICE RF Module at LBNL	cavity, operation, coupling, experiment	454
	T.H. Luo, A.J. DeMello, A.R. Lambert, D. Li, T.J. Loew, S. Prestemon, S.P. Virostek, J.G. Wallig LBNL, Berkeley, California, USA T.G. Anderson, A.D. Bross, M.A. Palmer Fermilab, Batavia, Illinois, USA Y. Torun IIT, Chicago, Illinois, USA
	The international Muon Ionization Cooling Experiment aims to demonstrate the transverse cooling of a muon beam by ionization in energy absorbers. The final MICE cooling channel configuration has two RF modules, each housing a 201 MHz RF cavity used to compensate the longitudinal energy loss in the absorbers. The assembly of MICE RF Module is being carried out at LBL. In this paper we will report the recent progress on the assembly work.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW028
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW034	Final Commissioning of the MICE RF Module Prototype with Production Couplers	cavity, operation, coupling, Windows	474
	Y. Torun, P.G. Lane Illinois Institute of Technology, Chicago, Illlinois, USA T.G. Anderson, M. Backfish, D.L. Bowring, A. Moretti, D.V. Neuffer, D.W. Peterson, M. Popovic, K. Yonehara Fermilab, Batavia, Illinois, USA B.T. Freemire IIT, Chicago, Illinois, USA T.L. Hart UMiss, University, Mississippi, USA A.V. Kochemirovskiy University of Chicago, Chicago, Illinois, USA T.H. Luo LBNL, Berkeley, California, USA
	Funding: Supported by the US Department of Energy Office of Science through the Muon Accelerator Program. We report operational experience from the prototype RF module for the Muon Ionization Cooling Experiment (MICE) with final production couplers at Fermilab's MuCool Test Area. This is the last step in fully qualifying the RF modules for operation in the experiment at RAL.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW034
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW040	Electron Beam Excitation of a Surface Wave in mm-Wave Open Accelerating Structures	electron, detector, experiment, simulation	494
	M. Dal Forno, G.B. Bowden, C.I. Clarke, V.A. Dolgashev, M.J. Hogan, D.J. McCormick, A. Novokhatski, B.D. O'Shea, S.G. Tantawi, S.P. Weathersby SLAC, Menlo Park, California, USA B. Spataro INFN/LNF, Frascati (Roma), Italy
	Funding: Work supported by the US DOE under contract DE-AC02-76SF00515. As part of research on the physics of rf breakdowns we performed experiments with high gradient traveling-wave mm-wave accelerating structures. The accelerating structures are open, composed of two identical halves separated by an adjustable gap. The electromagnetic fields are excited by an ultra-relativistic electron beam. We observed that a confined travelling-wave mode exists in half of the accelerating structure. The experiments were conducted at FACET facility at SLAC National Accelerator Laboratory. Depending on the gap width, the accelerating structure had beam-synchronous frequencies that vary from 90 to 140 GHz. When we opened the gap by more than half wavelength the synchronous wave remains trapped. Its behavior is consistent with the so called "surface wave". We characterized this beam-wave interaction by several methods: measurement of the radiated rf energy with the pyro-detector, measurement of the spectrum with an interferometer, measurement of the beam deflection by using the beam position monitors and profile monitor.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW040
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW041	Measurements of RF Breakdowns in Beam Driven mm-Wave Accelerating Structures	electron, experiment, detector, collider	497
	M. Dal Forno, G.B. Bowden, C.I. Clarke, V.A. Dolgashev, M.J. Hogan, D.J. McCormick, A. Novokhatski, S.G. Tantawi, S.P. Weathersby SLAC, Menlo Park, California, USA B. Spataro INFN/LNF, Frascati (Roma), Italy
	Funding: Work supported by the US DOE under contract DE-AC02-76SF00515 We studied the physics and properties of rf breakdowns in high gradient traveling-wave accelerating structures at 100 GHz. The structures are open, made of two halves with a gap in between. The rf fields were excited in the structure by an ultra-relativistic electron beam generated by the FACET facility at the SLAC National Accelerator Laboratory. We observed rf breakdowns generated in the presence of GV/m scale electric fields. We varied the rf fields excited by the FACET bunch by moving structure relative to the beam and by changing the gap between structure halves. Reliable breakdowns detectors allowed us to measure the rf breakdown rate at these different rf parameters. We measured radiated rf energy with a pyro-detector. When the beam was off-axis, we observed beam deflection in the beam position monitors and on the screen of a magnetic spectrometer. The measurements of the deflection allowed us to verify our calculation of the accelerating gradient.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW041
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW043	Overview of High Power Vacuum Dry RF Load Designs	linac, klystron, accelerating-gradient, interface	504
	A.K. Krasnykh, A. Brachmann, F.-J. Decker, T.J. Maxwell, J. Sheppard SLAC, Menlo Park, California, USA
	Funding: Work supported by US Department of Energy under contract DE-AC02-76SF00515 A specific feature of RF linacs based on the pulsed traveling wave (TW) mode of operation is that only a portion of the RF energy is used for the beam acceleration. The residual RF energy has to be terminated into an RF load. Higher accelerating gradients require higher RF sources and RF loads, which can stably terminate the residual RF power. This overview will outline vacuumed RF loads only. A common method to terminate multi-MW RF power is to use circulated water (or other liquid) as an absorbing medium. A solid dielectric interface (a high quality ceramic) is required to separate vacuum and liquid RF absorber mediums. Using such RF load approaches in TW linacs is troubling because there is a fragile ceramic window barrier and a failure could become catastrophic for linac vacuum and RF systems. Traditional loads comprising of a ceramic disk have limited peak and average power handling capability and are therefore not suitable for high gradient TW linacs. This overview will focus on 'vacuum dry' or 'all-metal' loads that do not employ any dielectric interface between vacuum and absorber. The first prototype is an original design of RF loads for the Stanford Two-Mile Accelerator.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW043
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY007	Mechanical Design and 3-D Coupled RF, Thermal-Structural Analysis of Normal Conducting 704 MHz and 2.1 GHz Cavities for LEReC Linac	cavity, simulation, software, operation	525
	J.C. Brutus, S.A. Belomestnykh, I. Ben-Zvi, M. Blaskiewicz, J.M. Brennan, A.V. Fedotov, M.C. Grau, C. Pai, L. Snydstrup, J.E. Tuozzolo, B. P. Xiao, T. Xin, W. Xu, A. Zaltsman BNL, Upton, Long Island, New York, USA V. Veshcherevich Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE. Two normal conducting cavities operating at 704 MHz and 2.1 GHz will be used for the Low Energy RHIC electron Cooling (LEReC) under development at BNL to improve RHIC luminosity for heavy ion beam energies below 10 GeV/nucleon. The single cell 704 MHz cavity and the 3-cell 2.1 GHz third harmonic cavity will be used in LEReC to correct the energy spread introduced in the SRF cavity. The successful operation of normal RF cavities has to satisfy both RF and mechanical requirements. 3-D coupled RF-thermal-structural analysis has been performed on the cavities to confirm the structural stability and to minimize the frequency shift resulting from thermal and structural expansion. In this paper, we will present an overview of the mechanical design, results from the RF-thermal-mechanical analysis, progress on the fabrication and schedule for the normal conducting RF cavities for LEReC.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY007
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY010	RF Design of Normal Conducting 704 MHz and 2.1 GHz Cavities for LEReC Linac	cavity, HOM, impedance, simulation	532
	B. P. Xiao, I. Ben-Zvi, M. Blaskiewicz, J.M. Brennan, J.C. Brutus, A.V. Fedotov, H. Hahn, G.T. McIntyre, C. Pai, K.S. Smith, J.E. Tuozzolo, Q. Wu, T. Xin, W. Xu, A. Zaltsman BNL, Upton, Long Island, New York, USA S.A. Belomestnykh Fermilab, Batavia, Illinois, USA S.A. Belomestnykh, I. Ben-Zvi, T. Xin Stony Brook University, Stony Brook, USA V. Veshcherevich Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 and by National Energy Research Scientific Computing Center under contract No. DE-AC02-05CH11231 by US DOE. To improve RHIC luminosity for heavy ion beam energies below 10 GeV/nucleon, the Low Energy RHIC electron Cooler (LEReC) is currently under development at BNL. Two normal conducting cavities, a single cell 704 MHz cavity and a 3 cell 2.1 GHz third harmonic cavity, will be used in LEReC for energy spread correction. Currently these two cavities are under fabrication. In this paper we report the RF design of these two cavities.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY010
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY032	Design and Upgrade the Safety System for the SRF Electronic System at the Taiwan Photon Source	SRF, cryogenics, storage-ring, PLC	567
	F.-T. Chung, F.-Y. Chang, L.-H. Chang, M.H. Chang, L.J. Chen, M.-C. Lin, Z.K. Liu, C.H. Lo, C.L. Tsai, M.H. Tsai, Ch. Wang, M.-S. Yeh, T.-C. Yu NSRRC, Hsinchu, Taiwan
	This paper presents some new designs and upgrades of a SRF interlock and electronic system. Based on the experience from Taiwan Light Source (TLS) that uses one Cornell-type superconducting cavity made by ACCEL in the storage-ring RF system [1], in the new TPS SRF system [3] home-made LLRF and SRF electronics [4] are constructed for two KEKB-type superconducting cavities [2] that are installed in the storage ring of circumference 518 m. For reliable operation of the TPS SRF system, enhanced safety functions of the system were added to improve the original SRF system in TLS. The improved functions can provide both the operators and the RF systems with a safer environment and clearer messages for trouble-shooting and malfunction status indications.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY032
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY036	High-harmonic mm-Wave Frequency Multiplication using a Gyrocon-like Device	cavity, electron, coupling, plasma	579
	F. Toufexis, V.A. Dolgashev, M.V. Fazio, A. Jensen, S.G. Tantawi, A.R. Vrielink SLAC, Menlo Park, California, USA P. Borchard Dymenso LLC, San Francisco, USA
	Funding: This project was funded by U.S. Department of Energy under Contract No. DE-AC02-76SF00515, and the National Science Foundation. Traditional linear interaction RF sources, such as Klystrons and Traveling Wave Tubes, fail to produce significant power levels at millimeter wavelengths. This is because their critical dimensions are small compared to the wavelength, and the output power scales as the square of the wavelength. We present a vacuum tube technology, where the device size is inherently larger than the operating wavelength. We designed a low–voltage mm–wave source, with an output interaction circuit based on a spherical sector cavity. This device was configured as a phased-locked frequency multiplier. We report the design and cold test results of a proof-of-principle fifth harmonic frequency multiplier with an output frequency of 57.12 GHz.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY036
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY037	GaN Class-F Power Amplifier for Klystron Replacement	klystron, electron, operation, controls	583
	A.V. Smirnov RadiaBeam Systems, Santa Monica, California, USA R.B. Agustsson, S. Boucher, D.I. Gavryushkin, J.J. Hartzell, K.J. Hoyt, A.Y. Murokh, T.J. Villabona RadiaBeam, Santa Monica, California, USA
	Funding: This work was supported by the U.S. Department of Energy (award No. DE-SC0013136) The vacuum-tube-based RF amplifiers are relatively inefficient and becoming obsolete as the RF world has been progressively converting to solid state technology. Currently, the JLAB upgrade program requires 340 amplifiers capable of 8 kW CW at 1497 MHz while operating at more than 55-60% efficiency to replace their klystrons. Here we explore the possibility of a klystron replacement employing high electron mobility packaged GaN transistors applied in an array of Class-F amplifiers. The inputs and outputs of the many modules needed to make a complete amplifier are connected via precise, in-phase, low-loss, broadband, combiners-dividers. We describe early prototypes of the amplifiers as well as the combiners-dividers and discuss the design features and challenges of such a scheme. This approach can be applied to other national facilities and also for replacement of the klystrons in Middle Energy Electron-Ion Collider which requires about 1.8 MW CW power in total to be produced at 952.6 MHz frequency including 2x12.5 kW power for "crabbing" and 0.53 MW for electron cooling.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY037
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOR005	Longitudinal Wakefields in the Undulator Section of SXFEL User Facility	undulator, FEL, wakefield, electron	595
	M. Song, H.X. Deng, C. Feng, D. Huang, B. Liu, D. Wang SINAP, Shanghai, People's Republic of China
	Shanghai soft x-ray free electron laser (SXFEL) user facility based on multi-stage seeded-FEL and self-amplified spontaneous emission (SASE) is recently proposed, which is aiming at generating 4-2nm fully-coherent, high-brightness FEL pulse. In this paper, the wakefields arise from the resistive wall and surface roughness in the vacuum chamber is obtained by theoretical models. And the computations of geometric wakefields are carried out using ABCI. According to the tracked beam profile, the overall wakefields in the undulator section of SXFEL user facility are presented. K. Bane, G. Stupakov, SLAC-PUB-15951, May 2014. ** ABCI website: http://abci.kek.jp/abci.htm
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR005
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOR007	Local Impedance Measurements at ALBA from Turn-by-Turn Acquisition	impedance, insertion, lattice, optics	598
	M. Carlà, G. Benedetti, T.F.G. Günzel, U. Iriso, Z. Martí ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
	A transverse impedance source manifests itself, among other ways, by producing a small defocusing kick which depends on the beam bunch charge. By repeating optics measurements for different bunch charges, it is possible to disentangle the contribution produced by each impedance source from the dominating focusing effects given by the machine optics. But hunting for such faint defocusing effects poses strong requirements on the precision and sensibility of the measurements, and slow machine drifts or different thermal conditions shall be avoided. In this report, we present a novel method to assess in a fast and precise manner machine optics for different bunch charges using BPM turn-by-turn data and hybrid filling patterns. Finally, measurements for different ALBA machine components like scrapers and In-vacuum undulators are compared with simulation results.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR007
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOR008	Beam Induced RF Heating in LHC in 2015	impedance, operation, injection, monitoring	602
	B. Salvant, O. Aberle, M. Albert, R. Alemany-Fernandez, G. Arduini, J. Baechler, M.J. Barnes, P. Baudrenghien, O.E. Berrig, N. Biancacci, G. Bregliozzi, J.V. Campelo, F. Carra, F. Caspers, P. Chiggiato, A. Danisi, H.A. Day, M. Deile, D. Druzhkin, J. F. Esteban Müller, S. Jakobsen, J. Kuczerowski, A. Lechner, R. Losito, A. Masi, N. Minafra, E. Métral, A.A. Nosych, A. Perillo Marcone, D. Perini, S. Redaelli, F. Roncarolo, G. Rumolo, E.N. Shaposhnikova, J.A. Uythoven, C. Vollinger, A.J. Välimaa, N. Wang, M. Wendt, J. Wenninger, C. Zannini CERN, Geneva, Switzerland M. Bozzo INFN Genova, Genova, Italy J.F. Esteban Müller EPFL, Lausanne, Switzerland N. Wang IHEP, Beijing, People's Republic of China
	Following the recurrent beam induced RF issues that perturbed LHC operation during LHC Run 1, a series of actions were put in place to minimize the risk that similar issues would occur in LHC Run 2: longitudinal impedance reduction campaign and/or improvement of cooling for equipment that were problematic or at the limit during Run 1, stringent constraints enforced on new equipment that would be installed in the machine, tests to control the bunch length and longitudinal distribution, additional monitoring of temperature, new monitoring tools and warning chains. This contribution reports the outcome of these actions, both successes as well as shortcomings, and details the lessons learnt for the future runs.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR008
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOR016	Impedance Study with Single Bunch Beam at Taiwan Photon Source	impedance, photon, storage-ring, synchrotron	630
	C.-C. Kuo, P.J. Chou, K.T. Hsu, K.H. Hu, C.C. Liang, C.Y. Liao, Z.K. Liu, H.-J. Tsai, F.H. Tseng NSRRC, Hsinchu, Taiwan
	The impedance at Taiwan Photon Source was investigated. The effects of bunch current such as a tune change, a synchronous phase shift and a bunch lengthening under operation conditions at various stages were measured; the machine impedances were deduced. This report presents the results with insertion devices in various configurations.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR016
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOW001	Status of the 1.3 GeV Booster Synchrotron for Generating High Energy Gamma Rays at Tohoku University	controls, dipole, operation, booster	701
	F. Hinode, H. Hama, S. Kashiwagi, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi, C. Tokoku Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
	The reconstruction work of accelerator complex for the Great East Japan Earthquake in March 2011 had been conducted in Research Center of Electron Photon Science, Tohoku University. Since restoration of the user machine time in 2013, the approved beam time have been regularly implemented as scheduled. Currently, the 1.3 GeV Booster STorage (BST) ring has been well utilized to generate the high energy gamma-rays as before the disaster. The high energy gamma-rays were produced via Bremsstrahlung by inserting an internal target wire to the beam orbit after the beam acceleration. Since the user machine time was recovered, there were some improvements so far, i.e. realignment of synchrotron magnets, orbit correction in energy ramping process by updating the control of power supplies for steering magnets etc., which brought an increase of the beam current in the maximum energy. Present operational status and recent progress of beam performance in the BST ring are reported.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOW001
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOW006	Planning and Controlling of the Cold Accelerator Sections Installation in XFEL	status, laser, electron, free-electron-laser	716
	M. Bousonville, S. Choroba, F. Eints DESY, Hamburg, Germany
	The installation of the main linear accelerator in the 2 km European XFEL (X-Ray Free-Electron Laser) tunnel is currently under way. The accelerator consists of nine so-called cryo-strings. A typical cryo-string comprises 12 accelerator modules, which will be fed by three RF stations. Furthermore, the installation of electronic racks, cables, power and water supply etc. takes place. To enable a most effective installation of the accelerator components, planning and controlling methods, which had first been developed for the RF system work package, were adapted for the entire main linear accelerator. As a first step, a process plan was developed in cooperation with the work package leaders. On the basis of this plan, the installation process is promoted by several measures: The status of the installation is precisely registered by weekly queries which enable monitoring of the progress and feedback to everyone involved. With this information at hand, the installation process can be controlled and plan deviations can be corrected. Furthermore, the experience gained at one cryo-string is used to optimise the plan for the next cryo-string installation.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOW006
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY011	Estimating the Transverse Impedance in the Fermilab Recycler	impedance, proton, quadrupole, dipole	867
	R. Ainsworth, P. Adamson, A.V. Burov, I. Kourbanis, M.-J. Yang Fermilab, Batavia, Illinois, USA
	Impedance could represent a limitation of running high intensity bunches in the Fermilab recycler. With high intensity upgrades foreseen, it is important to quantify the impedance. To do this, studies have been performed measuring the tune shift as a function of bunch intensity allowing the transverse impedance to be derived.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY011
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY024	Development of a 325 MHz Ladder-RFQ of the 4-Rod-Type	rfq, proton, linac, ion	899
	M. Schütt, U. Ratzinger IAP, Frankfurt am Main, Germany C. Zhang GSI, Darmstadt, Germany
	In order to have an inexpensive alternative to 4-Vane RFQs above 200 MHz, we study the possibilities of a Ladder-RFQ. The 325 MHz RFQ is designed to accelerate protons from 95 keV to 3.0 MeV according to the design parameters of the research program with cooled antiprotons at FAIR. This particular high frequency for an RFQ creates difficulties, which are challenging in developing a cavity. In order to define a satisfactory geometrical configuration for this resonator, both from the RF and the mechanical point of view, different designs have been examined and compared. Very promising results have been reached with a ladder type RFQ, which has been investigated since 2013. Due to its geometric size the manufacturing as well as maintenance is not that complex compared with welded accelerators. The manufacturing, coppering and assembling of a 0.8 m prototype RFQ is finished. We present recent measurements of the rf-field, frequency-tuning, field flatness and the mode spectrum.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY024
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY040	Design of the 100 MeV Proton Beam Line for Low Flux Application	target, octupole, beam-transport, proton	938
	H.-J. Kwon, Y.-S. Cho, C.R. Kim, H.S. Kim, S.G. Lee, S. Lee, S.P. Yun Korea Atomic Energy Research Institute (KAERI), Gyeongbuk, Republic of Korea
	Funding: This work was supported by the Ministry of Science, ICT & Future Planning of the Korean Government. KOMAC has been operating two beam lines for user service since 2013. A new beam line was completed in 2015 for radioisotope production and has a plan to be commissioned in 2016. Another beam line was proposed to supply low flux beam to users. The maximum energy and average current are 100 MeV and 10 nA. The beam line consists of collimator, energy degrader, dipole magnet for energy separation and octupole magnet for uniform beam production. In this paper, the design of the beam line and its components is presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY040
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY041	Commissioning of New Proton and Light Ion Injector for Nuclotron-Nica	rfq, linac, ion, simulation	941
	S.M. Polozov, V.S. Dyubkov, M. Gusarova, T. Kulevoy, A.A. Martynov, A.S. Plastun, A.V. Samoshin MEPhI, Moscow, Russia V. Aleksandrov, A.V. Butenko, B.V. Golovenskiy, A. Govorov, V. Kobets, A.D. Kovalenko, V. Monchinsky, V.V. Seleznev, A.O. Sidorin, G.V. Trubnikov JINR, Dubna, Moscow Region, Russia V. Andreev, A.I. Balabin, S.V. Barabin, V.A. Koshelev, A.V. Kozlov, G. Kropachev, R.P. Kuibeda, T. Kulevoy, V.G. Kuzmichev, D.A. Liakin, A.Y. Orlov, A.S. Plastun, D.N. Selesnev, A. Sitnikov, Yu. Stasevich ITEP, Moscow, Russia A.P. Durkin MRTI RAS, Moscow, Russia K.A. Levterov JINR/VBLHEP, Dubna, Moscow region, Russia S.V. Vinogradov MIPT, Dolgoprudniy, Moscow Region, Russia
	The new accelerator complex Nuclotron-based Ion Collider fAcility (NICA) is now under development and construction at JINR. New complex is assumed to operate using two injectors: the Alvarez-type linac LU-20 as injector of light ions, polarized protons and deuterons and a new linac HILac of heavy ions. Now the modernization of LU-20 is also realized and old pulse DC injector is planning to replace by RFQ linac. New RFQ linac was developed and manufactured and is now under commissioning at Nuclotron injectors hall. New results of RFQ linac resonator testing and measurements, RF power load and linac testing with deuterium and carbon beam will discuss in this report.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY041
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY049	The PXIE LEBT Design Choices	ion, rfq, ion-source, solenoid	958
	L.R. Prost, A.V. Shemyakin Fermilab, Batavia, Illinois, USA
	Funding: Operated by Fermi Research Alliance, LLC, under Contract DE-AC02-07CH11359 with the United States Department of Energy Typical front-ends of modern light-ion high-intensity accelerators typically consist of an ion source, a Low Energy Beam Transport (LEBT), a Radiofrequency Quadrupole and a Medium Energy Beam Transport (MEBT), which is followed by the main linac accelerating structures. Over the years, many LEBTs have been designed, constructed and operated very successfully. In this paper, we present the guiding principles and compromises that lead to the design choices of the PXIE LEBT, including the rationale for a beam line that allows un-neutralized transport over a significant portion of the LEBT whether the beam is pulsed or DC.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY049
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY051	Manufacturing and the LLRF Tests of the SANAEM RFQ	rfq, cavity, LLRF, simulation	964
	G. Turemen, Y. Akgun, A. Alacakir, A.S. Bolukdemir, I. Kilic, B. Yasatekin TAEK - SANAEM, Ankara, Turkey G. Unel UCI, Irvine, California, USA H. Yildiz Istanbul University, Istanbul, Turkey
	Funding: Turkish Atomic Energy Authority Turkish Atomic Energy Authority is working on building an experimental proton beamline with local resources at the Saraykoy Nuclear Research and Training Center (SANAEM). Manufacturing of the radio frequency quadrupole (RFQ) was started after the beam dynamics and 3D electromagnetic simulation studies were performed. The vanes were machined with a three axis CNC machine. A CMM was used for the acceptance tests of the vanes and also for assembling. Production and assembly results were found acceptable for this cavity, the very first one developed in Turkey. Copper plating was performed by electroplating the aluminum vanes. The plated vanes were bolted and bonded with eight screws, eight pins and two different adhesives. A silver paste was used for RF sealing and a low vapor pressure epoxy was used for vacuum isolation. First LLRF tests of the RFQ were done with a bead-pull setup and a VNA. A N-type RF coupler and a pick-up were used for the LLRF tests. Phase shift method was used for the bead-pull tests. Cavity quality factor was measured with 3dB method for different RF sealing stages. This study summarizes the machining, assembling and the first LLRF tests of the SANAEM RFQ.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY051
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY054	Status of the ESS RFQ	rfq, cavity, status, operation	974
	D. Chirpaz-Cerbat, A. Albéri, A.C. Chauveau, M. Lacroix, N. Misiara, G. Perreu, O. Piquet, H. Przybilski, N. Sellami CEA/IRFU, Gif-sur-Yvette, France N. Berton, G. Bourdelle, M. Desmons, A.C. France, V.M. Hennion, P.-A. Leroy, B. Pottin CEA/DSM/IRFU, France
	The ESS Radio-Frequency Quadrupole (RFQ) is a 4-vanes resonant cavity designed at the frequency of 352.21 MHz. It must accelerate and bunch a 70mA proton beams from 75keV to 3.62MeV with a 4% duty cycle. The RFQ design has already been done, and documented in other papers. This one will present the global status of the RFQ, with technical solutions cho-sen for the main components (for fabrication and op-eration) and the present status of the RFQ fabrication.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY054
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY055	Technologies for Stabilizing the Dynamic Vacuum and Charge Related Beam Loss in Heavy Ion Synchrotrons	ion, heavy-ion, synchrotron, cryogenics	977
	P.J. Spiller, L.H.J. Bozyk, C. Omet, I. Pongrac, St. Wilfert GSI, Darmstadt, Germany
	With increasing the intensities of heavy ion beams in synchrotrons, charge related beam loss become more and more significant. In order to reduce space charge forces and to minimize the incoherent tune spread, the charge state of heavy Ions shall be lowered. Thus the cross section for charge related beam loss is further enhanced. For the FAIR project, GSI has developed a number of different technologies to stabilize the dynamic residual gas pressure and thereby to minimize charge related beam loss at high intensity heavy ion operation. Technologies suitable for such issues are, dedicated lattice structures, cold and warm ion catchers, NEG coated and cryogenic magnet chambers and cryo-adsorption pumps.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY055
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY057	The Linear IFMIF Prototype Accelerator (LIPAC) Design Development under the European-Japanese Collaboration	rfq, SRF, linac, cryomodule	985
	P. Cara, R. Heidinger Fusion for Energy, Garching, Germany N. Bazin, S. Chel, R. Gobin, J. Marroncle, B. Renard CEA/DSM/IRFU, France B. Brañas Lasala, D. Jiménez-Rey, J. Mollá, P. Méndez, I. Podadera CIEMAT, Madrid, Spain A. Facco, E. Fagotti, A. Pisent INFN/LNL, Legnaro (PD), Italy A. Kasugai, S. Keishi, S. O'hira JAEA, Aomori, Japan J. Knaster, A. Marqueta, Y. Okumura IFMIF/EVEDA, Rokkasho, Japan K. Sakamoto QST, Aomori, Japan
	The IFMIF aims to provide an accelerator-based, D-Li neutron source to produce high energy neutrons at sufficient intensity. Part of the BA agreement (Japan-EURATOM), the goal of the IFMIF/EVEDA project is to work on the engineering design of IFMIF and to validate the main technological challenges which includes a 125mA CW D⁺ accelerator up to 9 MeV mainly designed and manufactured in Europe. The components are in an advanced stage of manufacturing. The first components which allow the production of a 140 mA-100 keV deuteron beam have been delivered, installed and under commissioning at Rokkasho. The second phase (100 keV to 5 MeV) will end by March 2017. The third phase (short pulse) and forth phase (cw) will be the integrated commissioning of the LIPAc up to 9 MeV. The duration of the project has been recently extended up to end 2019 to allow the commissioning and operation of the whole accelerator (1MW). The aim of this paper is to give an overview of the LIPAc, currently under commissioning in Japan, to outline the engineering design and the development of the key components, as well as the expected outcomes of the engineering work, associated with the experimental program.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY057
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY058	Removing Known SPS Intensity Limitations for High Luminosity LHC Goals	impedance, simulation, emittance, shielding	989
	E.N. Shaposhnikova, T. Argyropoulos, T. Bohl, P. Cruikshank, B. Goddard, T. Kaltenbacher, A. Lasheen, J. Perez Espinos, J. Repond, B. Salvant, C. Vollinger CERN, Geneva, Switzerland
	In preparation of the SPS as an LHC injector its impedance was significantly reduced in 1999 - 2000. A new SPS impedance reduction campaign is planned now for the High Luminosity (HL)-LHC project, which requires bunch intensities twice as high as the nominal one. One of the known intensity limitations is a longitudinal multi-bunch instability with a threshold 3 times below this operational intensity. The instability is presently cured using the 4th harmonic RF system and controlled emittance blow-up, but reaching the HL-LHC parameters cannot be assured without improving the machine impedance. Recently the impedance sources responsible for this instability were identified and implementation of their shielding and damping is foreseen during the next long shutdown (2019 - 2020) in synergy with two other important upgrades: amorphous carbon coating of (part of) the vacuum chamber against the e-cloud effect and rearrangement of the 200 MHz RF system. In this paper the strategy of impedance reduction is presented together with beam intensity achievable after its realisation. The potential effect of other proposals on remaining limitations is also considered.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY058
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOBA01	Beam Commissioning of SuperKEKB	optics, coupling, detector, septum	1019
	Y. Funakoshi, T. Abe, T. Adachi, K. Akai, Y. Arimoto, K. Egawa, Y. Enomoto, J.W. Flanagan, H. Fukuma, K. Furukawa, N. Iida, H. Iinuma, H. Ikeda, T. Ishibashi, M. Iwasaki, T. Kageyama, H. Kaji, T. Kamitani, T. Kawamoto, S. Kazama, M. Kikuchi, T. Kobayashi, K. Kodama, H. Koiso, M. Masuzawa, T. Mimashi, T. Miura, F. Miyahara, T. Mori, A. Morita, S. Nakamura, T.T. Nakamura, H. Nakayama, T. Natsui, M. Nishiwaki, K. Ohmi, Y. Ohnishi, T. Oki, S. Sasaki, M. Satoh, Y. Seimiya, K. Shibata, M. Suetake, Y. Suetsugu, H. Sugimoto, M. Tanaka, M. Tawada, S. Terui, M. Tobiyama, S. Uehara, S. Uno, X. Wang, K. Watanabe, Y. Yano, S.I. Yoshimoto, R. Zhang, D. Zhou, X. Zhou, Z.G. Zong KEK, Ibaraki, Japan D. El Khechen LAL, Orsay, France
	In this report, we describe the machine operation in the first 3 months of the Phase 1 commissioning of SuperKEKB. The beam commissioning is smoothly going on. Vacuum scrubbing, the optics corrections and others are described.
	Slides TUOBA01 [9.346 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUOBA01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUZB02	Challenge of In-vacuum and Cryogenic Undulator Technologies	undulator, cryogenics, radiation, permanent-magnet	1080
	J.C. Huang, C.-H. Chang, C.H. Chang, T.Y. Chung, C.-S. Hwang, C.K. Yang, Y.T. Yu NSRRC, Hsinchu, Taiwan H. Kitamura RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
	An in-vacuum undulator (IVU) opens the utilization of high-brilliance X-rays in the medium energy storage rings. The development of a short-period undulator with low phase error becomes important to bring X-ray into a new unprecedented brilliant light source in an ultimate storage ring (USR). NdFeB or PrFeB cryogenic permanent magnet undulators (CPMUs) with a short period have been developed worldwide to obtain high brilliance of undulator radiation. A CPMU has high resistance against beam-induced heat load and allow to operate at a narrow gap. In a low emittance or ultimate storage ring, not only the performance of an undulator but the choice of the lattice functions is very important to obtain high bril-liance of synchrotron radiation. The optimum betatron functions and zero dispersion function shall be given for a straight section at IVU/CPMUs. In this paper, the relevant factors and design issues for IVU/CPMU will be discussed. Many technological challenges of a short-period undulator associated with beam induced-heat load, phase errors, and the deformation of in-vacuum girders will also be presented herein.
	Slides TUZB02 [5.204 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUZB02
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOCB01	First Commissioning of the SuperKEKB Vacuum System	electron, photon, status, positron	1086
	Y. Suetsugu, H. Hisamatsu, T. Ishibashi, K. Kanazawa, K. Shibata, M. Shirai, S. Terui KEK, Ibaraki, Japan
	The SuperKEKB, an electron-positron collider with asymmetric energies in KEK, has started the first commissioning with beams this year. One of major tasks in the commissioning is the beam scrubbing of new beam pipes in order to increase the beam lifetime and to decrease the background noise of the particle detector in the coming physics run. The temperatures and the vacuum pressures of new vacuum components, such as the bellows chambers, gate valves and the beam collimators, should be checked in this run. The decrease rate in the vacuum pressure are measured to estimate the vacuum scrubbing effect. Reported here will be the results obtained during the first commissioning and the present status of the vacuum system.
	Slides TUOCB01 [2.526 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUOCB01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB012	Optimization of the Field Integrals of Two Small Gap IDs for CLS	multipole, wiggler, undulator, synchrotron-radiation	1133
	M.F. Qian, Y.Z. He, H.F. Wang, W. Zhang, Q.G. Zhou SINAP, Shanghai, People's Republic of China
	An in-vacuum undulator and an in-vacuum wiggler have been developed for CLS at SSRF recently. The period lengths of the undulator and the wiggler are 20mm and 80mm respectively. Both IDs have the minimum gap of 5.2mm. The field integrals were measured for each magnet block with two poles and were sorted in-situ as they were installed on to the girders. Finally the field integrals of the undulator and the wiggler were shimmed by using the 'Magic Fingers' at the ends with a special algorithm. This paper reports the procedure and the results of the measurement and the optimization for the field integrals.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB012
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB017	The Injection Septum Magnet for the Collector Ring (FAIR)	injection, septum, operation, lattice	1145
	P.Yu. Shatunov, D.E. Berkaev, I. Koop, E.P. Semenov, D.B. Shwartz BINP SB RAS, Novosibirsk, Russia A. Dolinskyy, S.A. Litvinov GSI, Darmstadt, Germany Yu. A. Rogovsky Budker INP & NSU, Novosibirsk, Russia
	Collector Ring is one of the key installations of the FAIR project (Darmstadt, Germany). It is dedicated for stochastic cooling of incoming beams of antiprotons and rare ions. Additionally there is a mode of operation for experiments in the ring. Beams for all modes of operation are injected through one transfer channel. Extremely high acceptance of the ring (240 mm*mrad) leads to large apertures of all magnetic elements including the septum magnet. Meanwhile planned parameters of the magnetic field and magnetic field quality are comparatively strict. The present state of the design of the pulsed injection septum for the CR is presented in this article together with the concept of the injection system.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB017
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB026	Magnet System for a Compact Microtron	microtron, permanent-magnet, electron, operation	1164
	S.A. Kahn, R.J. Abrams, M.A.C. Cummings, R.P. Johnson, G.M. Kazakevich Muons, Inc, Illinois, USA
	Funding: Funded by DOE SBIR grant DE-SC0013795 A compact microtron can be an effective gamma source that can be transported to locations outside the laboratory. As part of a Phase I project we have studied a portable microtron that can accelerate electrons with energies of 6 MeV and above as a source for gamma and neutron production. The mass of the magnet is a significant contribution to the overall mass of the system. This paper will discuss conceptual designs for both permanent magnet and electromagnet systems. The choice of mictrotron RF frequency range is determined by the application requirements. The RF frequency influences the size of the microtron magnet and consequently its weight. We have looked at how the design would vary with the different frequency configurations.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB026
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB034	Design and Manufacture of a Superconducting Solenoid for D-Line of J-PARC Muon Facility	solenoid, operation, interface, radiation	1177
	T. Semba, Y. Hagiwara, S. Kido, S. Nakajima, Y. Tanaka Hitachi Ltd., Ibaraki-ken, Japan N. Kawamura, Y. Makida, Y. Miyake, H. Ohhata, K. Sasaki, K. Shimomura KEK, Ibaraki, Japan N. Kurosawa KEK, Tokai Branch, Tokai, Naka, Ibaraki, Japan Y. Murata Hitachi, Ltd., Energy and Environmental System Laboratory, Hitachi-shi, Japan P. Strasser High Energy Accelerator Research Organization (KEK), Institute of Materials Structure Science (IMSS), Ibaraki, Japan
	A superconducting solenoid for J-PARC muon facility was newly designed and manufactured. High Energy Accelerator Research Organization (KEK) has been operating the J-PARC Muon Science Establishment (MUSE) since 2008. Among its four muon beam lines, the decay muon line (D-Line) has been extracting and providing surface muons and positive decay muons up to a momentum of 50 MeV/c for various users, utilizing a superconducting solenoid. The D-Line as well as the other J-PARC facility suffered severe damages from the earthquake on March 11, 2011. It necessitated rebuilding of the damaged superconducting solenoid. New design parameter of the solenoid is as follows: length of solenoid: 6 m, diameter of warm bore: 0.2 m, magnetic field of bore center: 3.5 T, rated current: 415 A, superconducting wire: NbTi/Cu, quench protection: quench back heaters. The six-meter-long solenoid consists of twelve pieces of 0.5-meter-long superconducting coils. The entire solenoid is forced-indirectly cooled by supercritical helium flow. This report describes the design and manufacturing process of the newly built superconducting solenoid for D-Line of J-PARC muon facility.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB034
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB049	Development of Separator Cooling System for Helium	cryogenics, experiment, radiation, controls	1209
	W.R. Liao, S.-H. Chang, W.-S. Chiou, P.S.D. Chuang, F. Z. Hsiao, H.C. Li, T.F. Lin, H.H. Tsai NSRRC, Hsinchu, Taiwan
	A helium phase separator with a condenser is under fabrication and assembled at National Synchrotron Radiation Research Centre (NSRRC). The objective of a helium phase separator with its condenser is to separate two-phase helium flow and to re-condense vaporized gaseous helium with a cryocooler of Gifford-McMahon type. We developed a 100 litre (ltr) helium phase separator with a small heat loss as a prototype. The experimental results for the total cooling capacity of the phase separator are 0.73 W at 1.67 bara, which includes the effect of thermal conduction and thermal radiation from the environment. The helium liquefaction rate is 2 ltr/day with a 100 ltr vessel. The mechanism of heat transfer in phase separator was investigated and discussed. This paper presents the experiment of helium liquefaction process of 100 ltr separator with condenser, which was a key component of the helium phase separator.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB049
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB050	Development of Multi-channel Line for the NSRRC Cryogenic System	cryogenics, radiation, photon, synchrotron	1212
	P.S.D. Chuang, S.-H. Chang, W.-S. Chiou, F. Z. Hsiao, H.C. Li, W.R. Liao, T.F. Lin, H.H. Tsai NSRRC, Hsinchu, Taiwan
	For the past few years, the technology of X-ray photon source is getting more and more advanced, more and more countries are now striving to build the biggest synchrotron facility to meet its' need. In Taiwan, the construction of an electron accelerator with the energy of up to 3.5 GeV is constructed to fulfill the strong demands for an X-ray photon source with high brilliance and flux. Thus, to let the TPS be under stable operation, the cryogenic system is therefore very important. The refrigerant of the TPS Cryogenic System is Liquid Helium, to maintain liquid helium in its state, the temperature has to be maintained under 4.5K, however to let liquid helium turn into gas helium, only 20 W is needed. Therefore, the Multi-Channel Line is developed in our system to prevent heat from conduction in and letting liquid helium vaporize. Several mechanical parts have been designed to reduce heat loss and meet its needs, for example the Spacer. The paper presents a design methodology of long multi-channel helium cryogenic transfer lines. It describes some aspects thermo-mechanical calculation, supporting structure and contraction protection.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB050
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR002	Suppression of Concomitant Flow of Charged Particles in the Tandem Accelerator with Vacuum Insulation	ion, electron, proton, neutron	1225
	S.Yu. Taskaev, D.A. Kasatov, A.N. Makarov, Y.M. Ostreinov, I.M. Shchudlo, I.N. Sorokin BINP SB RAS, Novosibirsk, Russia
	Funding: The study was supported by the Grants from the Russian Science Foundation (Project no. 14-32-00006) and the Budker Institute of Nuclear Physics. A source of epithermal neutrons based on a tandem accelerator with vacuum insulation for Boron Neutron Capture Therapy of malignant tumors was proposed and constructed. Stationary proton beam with 2 MeV energy, 1.6 mA current, 0.1% energy monochromaticity and 0.5% current stability was obtained. The flow of charged particles accompanying the accelerated ion beam was detected and measured. To suppress this concomitant flow cooled diaphragm, cryopump and the electrostatic ring were installed in the input of accelerator. The surface of the vacuum vessel was covered with netting to suppress secondary electron emission. These steps have reduced the flow of charged particles 25 % of the ion beam to 0.5 % and to increase the current proton beam 3 times - up to 4.5 mA. The paper presents the results of research and declares plans to use the accelerator for the BNCT. D. Kasatov, et al. JINST 9 (2014) P12016. ** D. Kasatov, et al. Technical Physics Letters 41 (2015) 139-141.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR002
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR003	Three-fold Increase of the Proton Beam Current in the Vacuum Insulation Tandem Accelerator	ion, proton, tandem-accelerator, electron	1228
	I.M. Shchudlo, V. Dokutovich, D.A. Kasatov, A.N. Makarov, I.N. Sorokin, S.Yu. Taskaev BINP SB RAS, Novosibirsk, Russia
	Funding: The study was supported by the Grants from the Russian Science Foundation (Project no. 14-32-00006) and the Budker Institute of Nuclear Physics In BINP neutron source for boron neutron capture therapy of cancer based on the vacuum insulation tandem accelerator and lithium target for neutron generation was constructed. After optimization of the injection of negative hydrogen ions and modernization of the stripping target 1.6 mA 2 MeV proton beam was obtained. Improvements of the accelerator to suppress accompanying electron current were introduced, and after making changes to protection system of high voltage power supply a stable proton beam with a current of 4.5 mA was obtained. Analysis of the experimental results shows that the beam is accelerated without losses. Obtaining of proton beam with the current of more than 3 mA offers the prospects of using of accelerators for BNCT in cancer clinics.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR003
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR006	The ELENA Electron Cooler	electron, gun, solenoid, antiproton	1236
	G. Tranquille, J. Cenede, A. Frassier, L.V. Jørgensen, A.J. Kolehmainen, B. Moles, M.A. Timmins CERN, Geneva, Switzerland
	The ELENA (Extra Low ENergy Antiproton) ring will deliver antiprotons at an energy of just 100 keV to experiments aiming to precisely measure the properties of anti-hydrogen atoms. A crucial component of this decelerator ring is the electron cooler which will be used to counter the beam blow-up as the antiproton energy is reduced from 5.3 MeV to 100 keV. The electron cooler will operate at energies below 350 eV in a longitudinal guiding field of 100 G such that the perturbations to the ring can be easily corrected. We will present the design considerations as well as the production status of the cooler.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR006
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR029	Advanced EBIS Charge Breeder for Rare Isotope Science Project	electron, ion, gun, solenoid	1304
	S.A. Kondrashev, J.-W. Kim, Y.H. Park IBS, Daejeon, Republic of Korea H.J. Son Handong Global University, Pohang, Republic of Korea
	Rare Isotope Science Project (RISP) is under development in Korea to provide wide variety of intense rare isotope beams for nuclear physics experiments and applied science using both Isotope Separation On-Line (ISOL) and In-Flight Fragmentation (IF) techniques. Electron Beam Ion Source (EBIS) charge breeder is a key element to efficiently accelerate rare isotope ion beams produced by ISOL method. These beams will be charge-bred by an EBIS charge breeder to a charge-to-mass ratio (q/A) ≥ - and accelerated by linac post-accelerator to energies of 18.5 MeV/u. Utilization of 3 A electron beam and 6 T superconducting solenoid with wide (8) warm bore diameter will allow high efficient and fast charge breeding of rare isotope beams with exceptional degree of purity. The main features of RISP EBIS charge breeder design and current status of the project will be presented and discussed.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR029
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR030	Progress on RFQ Fabrication for RISP Accelerator	rfq, alignment, cavity, laser	1308
	B.-S. Park, B.H. Choi, I.S. Hong IBS, Daejeon, Republic of Korea
	The 81.25MHz Radio Frequency Quadrupole(RFQ), which was designed to accelerate various ion beams from the energy of 10 keV/u to 500 keV/u, is under development for the Rare Isotope Science Project(RISP). The 5 meter long RFQ consists of 9 sections and the total weight is roughly 16 tons. Each sections of RFQ aligned and installed by using a laser tracker on a supporter system. In this paper, the fabrication status of the RISP RFQ and the scheme of installation were described in detail. This work was supported by the RISP of IBS funded by the Ministry of Science, ICT and Future Planning(MSIP) and the National Research Foundation(NRF) of Korea(2013M7A1A1075764).
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR030
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR033	Low Emittance Growth in a LEBT with Un-neutralized Section	ion, ion-source, emittance, solenoid	1317
	L.R. Prost, J.-P. Carneiro, A.V. Shemyakin Fermilab, Batavia, Illinois, USA
	Funding: Operated by Fermi Research Alliance, LLC, under Contract DE-AC02-07CH11359 with the United States Department of Energy In a Low Energy Beam Transport line (LEBT), the emittance growth due to the beam's own space charge is typically suppressed by way of neutralization from either electrons or ions, which originate from ionization of the background gas. In cases where the beam is chopped, the neutralization pattern changes throughout the beginning of the pulse, causing the Twiss parameters to differ significantly from their steady state values, which, in turn, may result in beam losses downstream. For a modest beam perveance, there is an alternative solution, in which the beam is kept un-neutralized in the portion of the LEBT that contains the chopper. The emittance can be nearly preserved if the transition to the un-neutralized section occurs where the beam exhibits low transverse tails. This report discusses the experimental realization of such a scheme at Fermilab's PXIE, where low beam emittance dilution was demonstrated
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR033
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR040	The Development of a New Low Field Septum Magnet System for Fast Extraction in Main Ring of J-PARC	septum, operation, power-supply, extraction	1340
	T. Shibata, K. Ishii, H. Matsumoto, N. Matsumoto, T. Sugimoto KEK, Ibaraki, Japan K. Fan HUST, Wuhan, People's Republic of China
	The J-PARC Main Ring (MR) is being upgraded to improve its beam power to the design goal of 750 kW. One important way is to reduce the repetition period from 2.48 s to 1.3 s so that the beam power can be nearly doubled. We need to improve the septum magnets for fast extraction. We are improving the magnets and their power supplies. The present magnets which is conventional type have problem in durability of septum coil by its vibration, and large leakage field. The new magnets are eddy current type. The eddy current type does not have septum coil, but has a thin plate. We expect that there is no problem in durability, we can construct the thin septum plate, the leakage field can be reduced. The output of the present power supply are pattern current which of flat top is 10 ms width, the new one is short pulse which of one is 10 us. The short pulse consists of 1st and 3rd higher harmonic. We can expect that the flatness and reproducibility of flat top current can be improved. The calorific power can be also reduced. This paper will report the field measurement results with the eddy septum magnet systems.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR040
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR044	Beam Test of the New Beamline for Radio-Isotope Production at KOMAC	target, linac, isotope-production, proton	1349
	H.S. Kim KAERI, Daejon, Republic of Korea Y.-S. Cho, H.-J. Kwon, S.P. Yun Korea Atomic Energy Research Institute (KAERI), Gyeongbuk, Republic of Korea
	Funding: This work has been supported through KOMAC (Korea Multi-purpose Accelerator Complex) operation fund of KAERI by MSIP (Ministry of Science, ICT and Future Planning). A high power proton linac is under operation at Korea multi-purpose accelerator complex (KOMAC). Currently, two beamlines are available and used to provide 20-MeV beam and 100-MeV beam to users from various fields. An additional 100-MeV beamline has been constructed mainly for production of radio-isotopes such as Sr-82 and Cu-67. Proton beam with the beam energy of 100 MeV and the average current of 0.6 mA is directed to the production target, which is located in a water-filled target chamber, through a beam window made of AlBeMet. The beam size at the target is designed to be about 100 mm in diameter. Installation of the beamline components including 1.5 T bending magnet and the beam diagnostic devices such as BPM and BCM is finished and beam commissioning is planned to start in early 2016. The details of newly-constructed beamline and the initial beam test results will be given in this paper.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR044
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR053	Initial Experience with Carbon Stripping Foils at ISIS	injection, operation, synchrotron, proton	1378
	B. Jones, D.J. Adams, H. V. Smith STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	The ISIS Facility at the Rutherford Appleton Laboratory is a spallation neutron and muon source based upon a 50 Hz rapid cycling synchrotron accelerating ~3×10¹³ protons per pulse from 70 to 800 MeV to deliver a mean beam power of 0.2 MW to two target stations. Throughout its 30 years of operation ISIS has developed aluminium oxide foils in-house for H− charge exchange injection. The manufacturing and installation processes for these foils are time consuming, radiologically dose intensive and require a high degree of skill. Commercially available carbon based foils commonly used at other facilities, have the potential to greatly simplify foil preparation and installation in addition to improving beam quality. Similar foils would also be necessary for facility upgrades which increase injection energy to withstand the higher operating temperatures. This paper describes the initial experience of carbon foils in the ISIS synchrotron including issues relating to handling and mounting foils, their performance under beam operation and plans for further development.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR053
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMW021	Roman Pot Insertions in High-Intensity Beams for the CT-PPS Project at LHC	insertion, impedance, proton, luminosity	1473
	M. Deile, R. Bruce, A. Mereghetti, D. Mirarchi, S. Redaelli, B. Salvachua, B. Salvant, G. Valentino CERN, Geneva, Switzerland
	The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) at the LHC IP5 aims at exploring diffractive physics at high luminosity in standard LHC fills. It is based on 14 Roman Pots (RPs), designed to host tracking and time-of-flight detectors for measuring the kinematics of leading protons. To reach the physics goals, the RPs will finally have to approach the beams to distances of 15 beam σs (i.e. ~1.5 mm) or closer. After problems with showers and impedance heating in first high-luminosity RP insertions in 2012, the LS1 of LHC was used for upgrades in view of impedance minimisation and for adding new collimators to intercept RP-induced showers. In 2015 the effectiveness of these improvements was shown by successfully inserting the RPs in all LHC beam intensity steps to a first-phase distance of ~25 σs. This contribution reviews the measurements of debris showers and impedance effects, i.e. the data from Beam Loss Monitors, beam vacuum gauges and temperature sensors. The dependences of the observables on the luminosity are shown. Extrapolations to L=10³⁴ cm^-2 s^-1 and smaller distances to the beam do not indicate any fundamental problems. The plans for 2016 are outlined.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY017	Laser Driven Dielectric Accelerator in the Non-relativistic Energy Region	laser, acceleration, electron, radiation	1585
	K. Koyama, M. Uesaka The University of Tokyo, Nuclear Professional School, Ibaraki-ken, Japan S. Kurimura NIMS, Ibaraki, Japan H. Okamoto, S. Otsuki The University of Tokyo, Tokyo, Japan M. Yoshida KEK, Ibaraki, Japan
	Laser-driven dielectric accelerator (LDA) is suitable for delivering a submicron-size ultra-short electron beam, which is useful for studying basic processes of the radiation effect in a biological cell. Both the oblique incidence and the normal incidence configurations of LDA were studied. The oblique incidence configuration of LDA relaxes the synchronization condition as v_e=¥pm c L_G/¥left(¥λ+ L_G n ¥sin ¥theta ¥right) and is somewhat suitable for accelerating the non-relativistic electrons. The required energy to accelerate electrons in the oblique incidence configuration is smaller than that in the normal incidence configuration by a factor of ¥cos ¥theta, where ¥theta is the incidence angle of the laser beam. Two gratings each were made of different material structure of silica ({¥rm SiO₂}) were fabricated by the electron beam lithography. When a crystal silica was adopted, many large humps of several hundred nm size were observed in grooves of the grating. On the other hand, a glass silica had smoother grooves.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY017
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY032	Radiation from Open Ended Waveguide with a Dielectric Loading	radiation, electron, controls, simulation	1617
	S.N. Galyamin, A.A. Grigoreva, A.V. Tyukhtin, V.V. Vorobev Saint-Petersburg State University, Saint-Petersburg, Russia S. Baturin LETI, Saint-Petersburg, Russia S. Baturin Euclid TechLabs, LLC, Solon, Ohio, USA
	Funding: Work is supported by the Grant of the President of Russian Federation (No. 6765.2015.2) and the Grants from Russian Foundation for Basic Research (No. 15-32-20985, 15-02-03913). Terahertz radiation is considered as a promising tool for a number of applications. One possible way to emit THz waves is to pass short electron bunch through a waveguide structure loaded with dielectric. In our previous papers, we have analyzed this problem in both approximate* and rigorous*** formulation. However, we have encountered certain difficulties with calculations. In the present report, we are starting to develop another rigorous approach based on mode-matching technique and modified residue-calculus technique. We consider the radiation from the open-ended dielectrically loaded cylindrical waveguide placed inside regular cylindrical waveguide with larger radius. We present structure of reflected and transmitted modes and typical radiation patterns from the open end of larger radius waveguide. * S. Antipov et al., Appl. Phys. Lett., vol. 100, p. 132910, 2012. S.N. Galyamin et al., Opt. Express, vol. 22, No. 8, p. 8902, 2014. * S.N. Galyamin et al., in Proc. IPAC'15, pp. 2578-2580.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY032
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY033	Radiation of Charged Particle Flying into Chiral Isotropic Medium	polarization, radiation, plasma, interface	1620
	S.N. Galyamin, A.V. Tyukhtin Saint-Petersburg State University, Saint-Petersburg, Russia A.A. Peshkov HIJ, Jena, Germany
	Funding: Work is supported by the Grant of the Russian Foundation for Basic Research (No. 15-32-20985). In recent years, the interest to radiation of moving charged particles in media with chiral properties is connected with relatively new and prospective method for diagnostics of biological objects which uses the Cherenkov radiation ' Cherenkov luminescence imaging. Optical activity (chirality, gyrotropy) is typical or biological matter and is caused by mirrorless structure of molecules. Contrary to such gyrotropic medium as magnetized ionospheric plasma, aforementioned media are isotropic. One distributed model describing the frequency dispersion of isotropic chiral media is Condon model. In this report, we continue the investigation performed in our previous paper* where we dealt with the field produced by uniformly moving charge in infinite chiral isotropic medium. Moreover, we perform generalization of early paper**, where the problem with half-space was considered in the specific case of slow charge motion. We present typical radiation patterns in vacuum area and corresponding ellipses of polarization which allows determination of the chiral parameter of the medium. Spinelli A.E. et al. // NIM A. 2011. V. 648. P. S310. Galyamin S.N. et al. // Phys. Rev. E. 2013. V. 88. P. 013206. * Engheta N., Mickelson A.R. // IEEE Trans. AP. 1982. V. 30. P. 1213.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY033
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY034	On Bunch Diagnostics with use of Surface Waves Generated on Planar Wire Grid	radiation, electronics, diagnostics, electromagnetic-fields	1623
	V.V. Vorobev, S.N. Galyamin, A.V. Tyukhtin Saint-Petersburg State University, Saint-Petersburg, Russia
	Funding: Work is supported by the Grant of the President of Russian Federation (No. 6765.2015.2) and the Grants from Russian Foundation for Basic Research (No. 15-32-20985, 15-02-03913). Periodic structures can be used for non-destructive diagnostics of charged particle bunches. We consider structures which consist of thin conducting parallel wires. It is assumed that the structure period is much less than the typical wavelength under consideration. Therefore the influence of the structure on the electromagnetic field can be described with help of the averaged boundary conditions. We consider radiation of bunches which move along the grid but transversely to wires. Unlike previous works the bunch is assumed to have essential transversal dimensions along with definite longitudinal charge distribution. In particular we analyze the effect of reflection of the surface wave from the structure edge. For all considered situations, analytical and numerical results demonstrate that analysis of the surface waves allows estimating the size and the shape of the bunch. A.V. Tyukhtin et al., Phys. Rev. ST AB 17, 122802 (2014); A.V. Tyukhtin et al., Phys. Rev. E 91, 063202 (2015). ** M.I. Kontorovich et al., Electrodynamics of Grid Structures (Moscow, 1987).
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY034
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY035	Short-wavelength Radiation of a Small Charged Bunch in Presence of a Dielectric Prism	radiation, target, optics, polarization	1626
	A.V. Tyukhtin, S.N. Galyamin Saint-Petersburg State University, Saint-Petersburg, Russia E.S. Belonogaya LETI, Saint-Petersburg, Russia
	Funding: Work is supported by the Grant from Russian Foundation for Basic Research (No. 15-02-03913). Investigation of radiation of a charged particle bunch in the presence of a large (compared with wavelengths under consideration) dielectric object can be performed using certain approximate methods. We develop here the method based on the known Stratton-Chu formulae which allows calculating the field everywhere outside the object including the Fresnel and Fraunhofer areas, as well as neighborhoods of focal points. The main problem considered here consists in investigation of radiation of a small bunch moving along boundary of a dielectric prism or in channel inside a prism. Approximate analytical solutions of the problem are obtained and typical numerical results are given. S.N. Galyamin and A.V. Tyukhtin, Phys. Rev. Lett. 113, 064802, 2014.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY035
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY041	Delivery Status of the ELI-NP Gamma Beam System	gun, solenoid, laser, linac	1635
	S. Tomassini, D. Alesini, A. Battisti, R. Boni, F. Cioeta, A. Delle Piane, E. Di Pasquale, G. Di Pirro, A. Falone, A. Gallo, S.I. Incremona, V.L. Lollo, A. Mostacci, S. Pioli, R. Ricci, U. Rotundo, A. Stella, C. Vaccarezza, A. Vannozzi, A. Variola INFN/LNF, Frascati (Roma), Italy A. Bacci, D.T. Palmer, L. Serafini Istituto Nazionale di Fisica Nucleare, Milano, Italy N. Bliss STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom F. Cardelli INFN-Roma1, Rome, Italy K. Cassou, Z.F. Zomer LAL, Orsay, France G. D'Auria Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy A. Giribono, V. Pettinacci INFN-Roma, Roma, Italy C. Hill STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom L. Palumbo Rome University La Sapienza, Roma, Italy L. Piersanti University of Rome La Sapienza, Rome, Italy
	The ELI-NP GBS is a high intensity and monochromatic gamma source under construction in Magurele (Romania). The design and construction of the Gamma Beam System complex as well as the integration of the technical plants and the commissioning of the overall facility, was awarded to the Eurogammas Consortium in March 2014. The delivery of the facility has been planned in for 4 stages and the first one was fulfilled in October 31st 2015. The engineering aspects related to the delivery stage 1 are presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY041
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOR008	Effect of the Various Impedances on Longitudinal Beam Stability in the CERN SPS	impedance, HOM, simulation, operation	1666
	A. Lasheen, T. Argyropoulos, J. Repond, E.N. Shaposhnikova CERN, Geneva, Switzerland
	The High Luminosity (HL)-LHC project at CERN aims at a luminosity increase by a factor ten and one of the necessary ingredients is doubling the bunch intensity to 2.4x10¹¹ ppb for beams with 25 ns bunch spacing. Many improvements are already foreseen in the frame of the LHC Injector Upgrade (LIU) project, but probably this intensity would still not be reachable in the SPS due to longitudinal instabilities. Recently a lot of effort went into finding the impedance sources of the instabilities. Particle simulations based on the latest SPS impedance model are now able to reproduce the measured instability thresholds and were used to determine the most critical impedance sources by removing them one by one from the model. It was found that impedance of vacuum flanges and of the already damped 630 MHz HOM of the main RF system gave for 72 bunches the comparable intensity thresholds. Possible intensity gains are defined for realistic impedance modifications and for various beam configurations (number of bunches, longitudinal emittances) and RF programs (single and double RF). The results of this study are used as a guideline for planning of a new campaign of the SPS impedance reduction.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR008
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOR011	Study of Microwave Instability for SLS-2	impedance, storage-ring, emittance, simulation	1678
	H.S. Xu, P. Craievich, M.M. Dehler, L. Stingelin PSI, Villigen PSI, Switzerland
	An ultra-low emittance electron storage ring is under development for the Upgrade of Swiss Light Source (SLS-2). An antechamber scheme consisting of round beam channel with 10 mm inner radius is considered to accommodate the required strong quadrupole and sextupole magnets, achieve the ultra-high vacuum, and absorb the undesired synchrotron radiation. However, the small size of vacuum chamber increases the susceptibility of the beam to the impedance induced collective instabilities. We will present the preliminary study of the microwave instability for SLS-2 storage ring considering the longitudinal Resistive-Wall (RW) impedance due to three different options for the beam chamber. The microwave instability thresholds are calculated under the conditions of two possible RF frequencies (100 MHz and 500 MHz) and three different materials (aluminum, copper, and stainless steel). The influences of third-harmonic cavities are also studied.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR011
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOR023	Investigation of Trapped Resonant Modes in Insertion Devices at the Australian Synchrotron	resonance, feedback, undulator, synchrotron	1710
	R.T. Dowd, M.P. Atkinson, M.J. Boland, G. LeBlanc, Y.E. Tan SLSA, Clayton, Australia D. Teytelman Dimtel, San Jose, USA
	The Australian Synchrotron light Source has 3 variable gap in-vacuum undulators (IVU) in the storage ring. Since installation, these devices have been the source of strong beam instabilities. These instabilities seem to behave as trapped resonant modes of very high Q and high frequency, although a definite source has not been identified. The presence of these instabilities has necessitated operating at unusually high chromaticity for much of the light source's operations. More recently transverse feedback has been able to control the instabilities and recent developments in diagnostics have allowed some investigation of the frequency and mode response of these resonances. The results of this investigation will be presented in this paper.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR023
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOR031	Trapped Ion Effects and Mitigation During High Current Operation in the Cornell DC Photoinjector	ion, radiation, experiment, linac	1735
	S.J. Full, A.C. Bartnik, I.V. Bazarov, J. Dobbins, B.M. Dunham, G.H. Hoffstaetter Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: U.S. Department of Energy (Grant No. DE-SC0012493), National Science Foundation (Award No. NSF-DMR 0807731) The Cornell high intensity photoinjector reaches a new regime of linac beam parameters where high continuous-wave electron beam currents lead to ion trapping. Above 10 mA, we have observed beam trips that limit stable machine operation to approximately 10^-15 minutes. By applying known ion clearing methods, the machine lifetime increases to at least 24 hours of continuous operation, suggesting that trapped ions are the most likely cause of the trips. In this paper we share some of our observations ion trapping in the photoinjector, as well as experimental tests of three common ion mitigation methods: clearing electrodes, beam shaking and bunch gaps.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR031
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOW003	High Average RF Power Tests With 2 RF Vacuum Windows at PITZ	gun, operation, Windows, emittance	1744
	Y. Renier, G. Asova, M. A. Bakr, P. Boonpornprasert, J.D. Good, M. Groß, C. Hernandez-Garcia, H. Huck, I.I. Isaev, D.K. Kalantaryan, M. Krasilnikov, O. Lishilin, G. Loisch, D. Malyutin, D. Melkumyan, A. Oppelt, M. Otevřel, G. Pathak, T. Rublack, I.V. Rybakov, F. Stephan, G. Vashchenko, Q.T. Zhao DESY Zeuthen, Zeuthen, Germany M. Bousonville, S. Choroba, S. Lederer DESY, Hamburg, Germany
	The Photo Injector Test facility at DESY, Zeuthen site (PITZ), was built with the aim to develop and characterize electron sources for future usage at FLASH and at the European XFEL. Recently, the main focus at PITZ has been the study of gun reliability and photoinjector performance at high average power. The goal is to get stable and reliable operation with 6.4 MW peak power in the gun at 650 us RF pulse length and 10 Hz repetition rate. To achieve this, a new RF feed system with two RF windows was installed at PITZ in 2014. During this test, the old gun 4.2 with a modified back-plane design for better cathode contact has been used. In this contribution the results of the RF conditioning of gun 4.2 with a detailed interlock analysis will be reported as well as results from recent electron beam characterization.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW003
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOW004	Status of the STAR Project	laser, electron, focusing, controls	1747
	A. Bacci, I. Drebot, L. Serafini, V. Torri Istituto Nazionale di Fisica Nucleare, Milano, Italy R.G. Agostino, R. Barberis, M. Ghedini, F. Martire, C. Pace UNICAL, Arcavacata di Rende, Italy D. Alesini, M. Bellaveglia, J.J. Beltrano, F.G. Bisesto, G. Borgese, B. Buonomo, G. Di Pirro, G. Di Raddo, A. Esposito, A. Gallo, A. Ghigo, F. Iungo, L. Pellegrino, A. Stella, C. Vaccarezza INFN/LNF, Frascati (Roma), Italy A. Cianchi INFN-Roma II, Roma, Italy G. D'Auria, A. Fabris, M. Marazzi Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy V. Petrillo Universita' degli Studi di Milano, Milano, Italy E. Puppin Politecnico/Milano, Milano, Italy M. Rossetti Conti Universita' degli Studi di Milano & INFN, Milano, Italy
	This paper reports on the final design and the work in progress on the STAR project (IPAC2014:WEPRO115), which is under construction at the Univ. of Calabria (Italy). The project is devoted to the construction of an advanced Thomson source of monochromatic tunable, ps-long, polarized X-ray beams, ranging from 40 up to 140 KeV . At present the buildings and main plants have been completed as the acquisition of main components: the RF photo-injector, the accelerating section, laser systems for collision and photo-cathode, RF Power Source and magnets are ready to start installation and site acceptance tests. The design of laser lines is complete and simulated by ZEMAX, aiming to minimize energy losses, optical distortions and providing a tunable experimental setup as well. The RF power network is close to be tested, it's based on a 55MW (2.5us pulse) S-band Klystron driven by a 500kV Pulse Forming Network based modulator and a Low Level RF system, running at 100 Hz. The Control System is been designed using EPICS and allows to manage easily and fastly each machine parameter. We expect to start commissioning the machine by the end of 2016 and obtain the first collisions within the first part of 2017.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW004
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOW034	Status Report of the Berlin Energy Recovery Linac Project BERLinPro	gun, SRF, cavity, linac	1827
	M. Abo-Bakr, W. Anders, K.B. Bürkmann-Gehrlein, A.B. Büchel, P. Echevarria, A. Frahm, H.-W. Glock, F. Glöckner, F. Göbel, B.D.S. Hall, S. Heling, H.-G. Hoberg, A. Jankowiak, C. Kalus, T. Kamps, G. Klemz, J. Knobloch, J. Kolbe, G. Kourkafas, J. Kühn, B.C. Kuske, P. Kuske, J. Kuszynski, D. Malyutin, A.N. Matveenko, M. McAteer, A. Meseck, C.J. Metzger-Kraus, R. Müller, A. Neumann, N. Ohm, K. Ott, E. Panofski, F. Pflocksch, J. Rahn, J. Rudolph, M. Schmeißer, O. Schüler, M. Schuster, J. Ullrich, A. Ushakov, J. Völker HZB, Berlin, Germany
	Funding: Work supported by the German Bundesministerium für Bildung und Forschung, Land Berlin and grants of Helmholtz Association The Helmholtz Zentrum Berlin is constructing the Energy Recovery Linac Prototype BERLinPro at the Berlin Adlershof site. The project is intended to expand the required accelerator physics and technology knowledge mandatory for the design, construction and operation of future synchrotron light sources. The project goal is the generation of a high current (100 mA), high brilliance (norm. emittance below 1 mm mrad) cw electron beam. We report on the project progress: since spring 2015 the building is under construction, ready for occupancy in January 2017. The planning phase for the first project stage is completed for the warm machine parts, the SRF gun and partly for the SRF booster. Most of the components have been ordered and are in fabrication with some already delivered. An update of the status of the various subprojects as well as a summary of future activities will be given. Project milestones and details of the timeline will be reviewed.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW034
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOW044	Experimental Investigation of THz Smith-Purcell Radiation From Composite Corrugated Capillary	radiation, simulation, detector, electron	1861
	K. Lekomtsev, A. Aryshev, M. Shevelev, N. Terunuma, J. Urakawa KEK, Ibaraki, Japan A. Ponomarenko, A.A. Tishchenko MEPhI, Moscow, Russia
	Funding: This work was supported by Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan. Terahertz part of electromagnetic spectrum has a variety of potential applications ranging from fundamental to security applications. Further advances in development of a linac based, tunable, and narrow band coherent source of THz radiation are very important. Mechanisms of Cherenkov radiation and Smith-Purcell radiation (SPR) [] may be used for generation of THz radiation via coherent emission [, ]. In this report we will present experimental investigations of the SPR generated from the corrugated capillary with a reflector, using the femtosecond multi-bunch electron beam of LUCX accelerator at KEK, Japan [*]. LUCX is capable to generate a train of 4 bunches each with 200 femtosecond (60 micrometer) duration and 200 micrometer transverse size. We will discuss the composite design of the capillary, measurements of the SPR angular distributions and the comparison of these measurements with PIC simulations. In addition, we will discuss SPR spectral characteristics; bunch energy modulation, introduced by the corrugated capillary; and the way in which the bunch spacing changes the spectrum and angular distributions of SPR. K.Lekomtsev et al., NIMB 355 (2015) 164 A. M. Cook et al., PRL 103, (2009) 095003. S. E. Korbly et al., PRL 94, (2005) 054803. ***A. Aryshev, arXiv:1507.03302 [physics.acc-ph]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW044

Paper

Title

Other Keywords

Page

MOYAA01

Commissioning of the MAX IV Light Source

storage-ring, emittance, injection, lattice

11

M. Eriksson, E. Al-Dmour, Å. Andersson, M.A.G. Johansson, S.C. Leemann, L. Malmgren, P.F. Tavares, S. Thorin
MAX IV Laboratory, Lund University, Lund, Sweden

This presentation reports on the beam commissioning status of MAX IV, experience gained and lessons learned, as well as future plans.

Slides MOYAA01 [6.682 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOYAA01

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB006

First Tests of SuperKEKB Luminosity Monitors during 2016 Single Beam Commissioning

luminosity, simulation, scattering, background

81

D. El Khechen, P. Bambade, A. Blin, P. Cornebise, D. Jehanno, V. Kubytskyi, Y. Peinaud, C. Rimbault
LAL, Orsay, France
Y. Funakoshi, Y. Ohnishi, S. Uehara
KEK, Ibaraki, Japan

The SuperKEKB e⁺e⁻ collider aims to reach a very high luminosity of 8 10³⁵ cm^-2s⁻¹, using highly focused ultra-low emittance bunches colliding every 4ns. Fast luminosity monitoring is required for luminosity feedback and optimisation in presence of dynamic imperfections. The aimed relative precision is about 10^-3 in 1ms, which can be in principle achieved thanks to the very large cross-section of the radiative Bhabha process at zero degree scattering angle. Diamond, Cherenkov and scintillator sensors are to be placed just outside the beam pipe, downstream of the interaction point in both rings, at locations with event rates consistent with the aimed precision and small enough backgrounds from single-beam particle losses. The initial configuration installed for the 2016 "phase 1" single beam commissioning will be described, including the sensors, mechanical setup, readout electronics and first stage DAQ. Preliminary measurements and analysis of beam gas Bremsstrahlung loss data collected with the luminosity monitors will be reported and compared with a detailed simulation, for several experimental conditions during the SuperKEKB commissioning.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB006

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB008

Modeling and Experimental Studies of Beam Halo at ATF2

scattering, coupling, damping, optics

88

R.J. Yang, P. Bambade, V. Kubytskyi
LAL, Orsay, France
A. Faus-Golfe, N. Fuster-Martínez
IFIC, Valencia, Spain
T. Naito
KEK, Ibaraki, Japan

The Accelerator Test Facility 2 (ATF2) at KEK is a prototype of the final focus system for the next generation of Future Linear Colliders(FCL). It aims to focus the beams to tens of nanometer transverse sizes and to provide stability at the few nm level. Achieving these goals requires modelling, measuring and suppressing of the transverse beam halo before the interaction point (IP). This paper presents a beam tail/halo generator based on realistic model and the investigation of vertical and horizontal beam tail/halo distribution at ATF2.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB008

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB011

ROSE, Measuring the Full 4D Transverse Beam Matrix of Ion Beams

emittance, ion, coupling, detector

98

M.T. Maier, X. Du, P. Gerhard, L. Groening, S. Mickat, H. Vormann, C. Xiao
GSI, Darmstadt, Germany

A ROtating System for Emittance measurements ROSE, to measure the full 4 dimensional transverse beam matrix of an ion beam has been developed and commissioned. Different ion beams behind the HLI at GSI have been used in two commissioning beam times. All technical aspects of ROSE have been tested, ROSE has been benchmarked against existing emittance scanners for horizontal and vertical projections, and the method, hard-, and software to measure the 4D beam matrix has been upgraded, refined, and successfully commissioned. The inter plane correlations of the HLI beam have been measured, yet as no significant initial correlations were found to be present, controlled coupling of the beam by using a skew triplet has been applied and confirmed with ROSE. The next step is to use ROSE to measure and remove the known inter plane correlations of a uranium beam before SIS18 injection.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB011

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB012

A High-Energy-Scrapersystem for the S-DALINAC Extraction - Design and Installation

electron, extraction, linac, dipole

101

L.E. Jürgensen, T. Bahlo, C. Burandt, T. Kürzeder, N. Pietralla, S. Weih, J. Wissmann
TU Darmstadt, Darmstadt, Germany
F. Hug
IKP, Mainz, Germany

Funding: *Funded by Deutsche Forschungsgemeinschaft under grant No. SFB 634
The superconducting Darmstadt linear electron accelerator (S-DALINAC) of the Institute for Nuclear Physics at Technische Universität Darmstadt delivers electron beams in cw-mode with energies up to 130 MeV. The accelerator consists of a 10-MeV injector and a 30-MeV main linac where superconducting 3-GHz microwave cavities are operated at a temperature of 2 K for beam acceleration. With three recirculation beamlines the main linac can be used up to four times. To improve the energy spread and the energy stability of the beam a new scrapersystem has been developed and installed. It changes the extraction beam line into a dispersion-conserving chicane consisting of four dipole magnets and three scrapers. The system includes scraping of x- and y-halo in two positions as well as improving and stabilizing energy spread on a dispersive part. We will present the design of the system and report on its installation into the accelerator complex.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB012

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB022

Conceptual Design for SR Monitor in the FCC Beam Emittance (Size) Diagnostic

extraction, diagnostics, emittance, brightness

133

T.M. Mitsuhashi, K. Oide
KEK, Ibaraki, Japan
F. Zimmermann
CERN, Geneva, Switzerland

A conceptual design for emittance diagnostics through a beam size measurement using the synchrotron radiation (SR) is studied for the FCC. For the FCC-ee, a X-ray interferometer is propose to measure a nano-radian order vertical beam size. Also conceptual design of SR monitor is studied for FCC-hh. In the FCC-hh, visible SR will emitted from bending magnet in the energy range from the injection (3TeV) to top energy (50TeV). Hard X-ray SR will only available in the energy upper than 30TeV. The various instrumentations using the visible SR is usable for all energy range. Around the top energy, the X-ray pinhole camera will convenient for beam diagnostics of emittance through the beam size measurement.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB022

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB024

Electron Cloud Measurements at J-PARC Main Ring

electron, detector, proton, extraction

137

B. Yee-Rendón, H. Kuboki, R. Muto, K. Satou, M. Tomizawa, T. Toyama, M. Uota
KEK, Ibaraki, Japan

Electron cloud instability is presented in most of the high intensity proton rings. During the Slow beam extraction (SX) mode at Main Ring of J-PARC, signals related with its formation were observed. An electron cloud detector is installed downstream of the ElectroStatic Septum (ESS), to measure the electron signal. Additionally, scintillation detector with photomultiplier, a proportional counter and photo-diode were set closely to the electron cloud detector to observe the beam lost. This paper presents the measurements of the electron cloud and some of the conditions which support its creation, for instance the signal of lost particle from the beam loss monitors, the residual gas in the vacuum duct by using vacuum pressure gauges, etc.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB024

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB026

Frequency and Time Domain Measurement of Coherent Transition Radiation

electron, laser, radiation, polarization

143

K. Kan, M. Gohdo, T. Kondoh, I. Nozawa, J. Yang, Y. Yoshida
ISIR, Osaka, Japan

Ultrashort electron beams are essential for light sources and time-resolved measurements. Electron beams can emit terahertz (THz) pulses using coherent transition radiation (CTR). Michelson interferometer is one of can-didates for analyzing the pulse width of an electron beam based on frequency-domain analysis. Recently, electron beam measurement using a photoconductive antenna (PCA) based on time-domain analysis has been investi-gated. In this paper, to improve beam diagnostics of ul-trashort electron beam, investigation of characteristics of a PCA for generation and frequency and time-domain measurement of THz pulses was conducted.
* I. Nozawa et al., Phys. Rev. ST Accel. Beams 17, 072803 (2014).
** K. Kan et al., Appl. Phys. Lett. 102, 221118 (2013).

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB026

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB029

Development Status of Linear Focal Cherenkov Ring Camera

electron, laser, photon, experiment

152

K. Nanbu, T. Abe, H. Hama, F. Hinode, S. Kashiwagi, T. Muto, I. Nagasawa, H. Saito, K. Takahashi, C. Tokoku
Tohoku University, Research Center for Electron Photon Science, Sendai, Japan

Linear focal Cherenkov ring camera (LFC-Camera) has been developed for single shot measurement of longitudinal phase space distribution of quasi-relativistic electron beam, where the electron's velocity still depends on its energy. The LFC-camera employs velocity dependence of opening angle of Cherenkov light produced by electron beam to observe its energy (momentum) distribution. Since the Cherenkov light contains the time information if the radiator medium is thin enough, we can get the longitudinal phase space distribution measuring both time and energy spectra simultaneously using a streak camera. We employ a thin silica aerogel with water-free hydrophobic treatment as Cherenkov radiator. We have evaluated characteristics of the silica aerogel radiator, and demonstration of the LFC-camera at a beam diagnosis section of t-ATCS is being proceeded.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB029

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB039

Design of Bunch Length Measurement System at the IRFEL Using a Martin-Puplett Interferometer

radiation, electron, detector, polarization

178

T.Y. Zhou, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, F.F. Wu, Y.L. Yang, Z.R. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Supported by the National Science Foundation of China (11575181, 11175173)
Electron bunch length measurement is of great significance for optimizing IRFEL performance. An optical autocorrelation system using coherent transition radiation (CTR) would be set up to measure the electron bunch length at the IRFEL. CTR can be occurred when short electron bunches traverse a vacuum-metal interface. A Martin-Puplett interferometer allowed measurement of the autocorrelation of the CTR signal. The basic principle and the main components of Martin-Puplett interferometer are elaborated in this paper.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB039

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB042

Design and Simulation of Button Beam Position Monitor for IR-FEL*

FEL, simulation, electron, electronics

187

X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, F.F. Wu, Y.L. Yang, T.Y. Zhou, Z.R. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: * Supported by the National Science Foundation of China (11575181, 11175173)
A new button-type beam position monitor(BPM) was designed for the IR-FEL project. Firstly, the longitudinal size of BPM needs to be short enough to save space because the entire machine of IR-FEL is very compact. And in the matter of installation problem, all four electrodes are deviated 30 degrees from the horizontal axis. Then, according to these two limited conditions and beam parameters, we builded up a simple model and did some simulated calculations to ensure a good performance of position resolution, which should be better than 50μm. The simulations include an estimation of induced signals in both time and frequency domains, horizontal and vertical sensitivities, mapping figures and so on. This button BPM will be manufactured in the near future and then we can do some off-line experiments to test it.
# Corresponding author (email: bgsun@ustc.edu.cn)

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB042

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB043

Preliminary Research of HLS II BLM System

storage-ring, detector, operation, site

190

F.F. Wu, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, J.G. Wang, Y.L. Yang, Z.R. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China
Y.K. Chen
IHEP, Beijing, People's Republic of China

Beam loss monitor system has been designed in many electron storages in order to indirectly measure lost electrons, which can be used to analysis beam loss mechanism and beam life. It can contribute to beam commissioning and improving stable operation of storage ring. According to lattice structure of the HLS II storage ring, 64 beam loss detectors have been located in the upper, lower, inner, outer side surfaces of vacuum chamber in the HLS II storage ring. Some preliminary researches based on the HLS II BLM system have been done. The results in successfully stable operation and unsuccessfully stable operation in beam commissioning stage were compared. Analysis of a sudden lost beam phenomenon were carried out.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB043

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR019

Beam Tests of a Prototype Stripline Beam Position Monitoring System for the Drive Beam of the CLIC Two-beam Module at CTF3

electronics, pick-up, impedance, operation

270

A. Benot-Morell, A. Faus-Golfe
IFIC, Valencia, Spain
A. Benot-Morell, M. Wendt
CERN, Geneva, Switzerland
A. Faus-Golfe
LAL, Orsay, France
J.M. Nappa, S. Vilalte
IN2P3-LAPP, Annecy-le-Vieux, France

Funding: MINECO contract no. FPA2013-47883-C2-1-P. CLIC Collaboration Agreement, contract no. KE2638/BE. FNRA contract no. ANR-11-IDEX-0003-02.
In collaboration with LAPP and IFIC, two units of a prototype stripline Beam Position Monitor (BPM) for the CLIC Drive Beam (DB), and its associated readout electronics have been successfully installed and tested in the Two-Beam-Module (TBM) at the CLIC Test Facility 3 (CTF3) at CERN. This paper gives a short overview of the BPM system and presents the performance measured under different Drive Beam configurations.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR023

Surface Characterization and Field Emission Measurements of Copper Samples inside a Scanning Electron Microscope

electron, controls, experiment, radio-frequency

283

J. Ögren, V.G. Ziemann
Uppsala University, Uppsala, Sweden
S.H.M. Jafri, K. Leifer
Uppsala University, Department of Engineering Sciences, Uppsala, Sweden

Vacuum breakdown in normal-conducting accelerating structures is a limiting factor for high gradient acceleration. Many aspects of the physics governing the breakdown process and its onset are yet to be fully understood. At Uppsala University we address these questions with an in-situ experimental setup mounted in an environmental scanning electron microscope. It consists of a piezo motor driven tungsten needle and a sample surface mounted on a piezo stage, allowing for nano-meter 3D-position control. One of the piezo motors controls the needle-sample gap while the two other scan across the surface. A DC-voltage up to 1 kV is applied across the gap and field emission currents from a copper surface are measured with an electrometer. Here we present the setup and some initial results.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR023

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR027

Employing Beam-Gas Interaction Vertices for Transverse Profile Measurements

detector, emittance, luminosity, real-time

296

M.N. Rihl, A. Alexopoulos, V. Baglin, C. Barschel, E. Bravin, G. Bregliozzi, N. Chritin, B. Dehning, M. Ferro-Luzzi, C. Gaspar, M. Giovannozzi, R. Jacobsson, L.K. Jensen, O.R. Jones, N.J. Jurado, V. Kain, M. Kuhn, B. Luthi, P. Magagnin, R. Matev, N. Neufeld, J. Panman, V. Salustino Guimaraes, B. Salvant, R. Veness, S. Vlachos
CERN, Geneva, Switzerland
A. Bay, F. Blanc, S. Gianì, G.J. Haefeli, P. Hopchev, T. Nakada, B. Rakotomiaramanana, O. Schneider, M. Tobin, Q.D. Veyrat, Z. Xu
EPFL, Lausanne, Switzerland
R. Greim, W. Karpinski, T. Kirn, S. Schael, G. Schwering, M. Wlochal, A. von Dratzig
RWTH, Aachen, Germany

Interactions of high-energy beam particles with residual gas offer a unique opportunity to measure the beam profile in a non-intrusive fashion. Such a method was successfully pioneered* at the LHCb experiment using a silicon microstrip vertex detector. During the recent Large Hadron Collider shutdown at CERN, a demonstrator Beam-Gas Vertexing system based on eight scintillating-fibre modules was designed**, constructed and installed on Ring 2 to be operated as a pure beam diagnostics device. The detector signals are read out and collected with LHCb-type front-end electronics and a DAQ system consisting of a CPU farm. Tracks and vertices will be reconstructed to obtain a beam profile in real time. Here, first commissioning results are reported. The advantages and potential for future applications of this technique are discussed.
* LHCb collaboration, Journal of Instrumentation, 9, P12005
** P. Hopchev in Proc. of IPAC 2014, June 15-20, 2014, Dresden Germany

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR027

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR046

Characterizing Supersonic Gas Jet-based Beam Profile Monitors

ion, simulation, diagnostics, electron

357

H.D. Zhang, A.S. Alexandrova, A. Jeff, V. Tzoganis, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
A.S. Alexandrova, A. Jeff, V. Tzoganis, C.P. Welsch, H.D. Zhang
The University of Liverpool, Liverpool, United Kingdom
A. Jeff
CERN, Geneva, Switzerland

Funding: Work supported by EU under contracts 215080 and 289191, Helmholtz Association (VH-NG-328) and STFC under the Cockcroft Institute core grant ST/G008248/1.
The next generation of high power, high intensity accelerators requires non-invasive diagnostics, particularly beam profile monitors. Residual gas-based diagnostics such as ionization beam profile or beam induced fluorescence monitors have been used to replace commonly used scintillating screens. At the Cockcroft Institute an alternative technique using a supersonic gas jet, shaped into a 45o curtain screen, was developed. It has already demonstrated its superior performance in terms of resolution and signal-to-noise ratio in comparison with residual gas monitors in experimental studies. The performance of this type of monitor depends on the achievable jet homogeneity and quality. Using a movable vacuum gauge as a scanner, the dynamic characteristics of the jet are studied. In this paper we also give an analysis of the resolution for this monitor in detail from the theory and ion drift simulation.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR046

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR052

Single-shot Bunch-by-Bunch Horizontal Beam Size Measurements using a Gated Camera at CesrTA

electron, positron, ion, synchrotron-radiation

364

S. Wang
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
R. Holtzapple
CalPoly, San Luis Obispo, California, USA

Funding: Work supported by NSF NSF PHY-1416318, PHYS-1068662, PHYS-1535696
A visible-light beam size monitor has been built and commissioned to measure transverse beam profiles at CESR-TA*. In order to eliminate beam jitter and to study bunch-by-bunch beam dynamics, a fast-gating camera has been utilized to measure single bunch transverse beam profiles. The minimum camera gate width is ~ 3ns which allows us to resolve single bunch beam dynamics along a CesrTA bunch train. Using single bunch interferometry at different bunch currents, we found that the horizontal beam sizes measured by gated camera are consistently less than those measured by a conventional CCD camera, demonstrating the elimination of turn-by-turn beam jitter with single shot capability. By stepping the camera trigger delay, we collected transverse beam profile images from each bunch in a 14ns-spacing 30-bunch train. The horizontal motion of each bunch as well as the horizontal beam size increases dramatically along an electron train but not along positron bunch trains under the same machine condition. The difference in single bunch horizontal dynamics may be a signature for the difference between electron cloud build-up for positron bunch trains versus ions present for electron bunch trains.
* S.T. Wang, D.L. Rubin, J. Conway, M. Palmer, D. Hartill, R. Campbell, R. Holtzapple, NIMA, 703 (2013) 80

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR052

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR056

Single-shot THz Spectrometer for Measurement of RF Breakdown in mm-wave Accelerators

detector, radiation, alignment, laser

374

S.V. Kutsaev, A.Y. Murokh, M. Ruelas, E.A. Savin, H.L. To
RadiaBeam Systems, Santa Monica, California, USA
M. Dal Forno, V.A. Dolgashev
SLAC, Menlo Park, California, USA
V. Goncharik
Logicware Inc, New York, USA
E.A. Savin
MEPhI, Moscow, Russia

Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics, under contract DE-SC0013684
We present a new instrument designed to detect RF pulse shortening caused by vacuum RF breakdown in mm-wave particle accelerators. RF breakdown limits the performance of high gradient RF accelerators. To understand the properties of these breakdowns, it is necessary to have diagnostics that reliably detect RF breakdowns. In X-band or S-band accelerators, RF breakdowns are detected by measuring RF pulse shortening, vacuum burst, or, if current monitors are available, spikes in the field-emitted currents. In mm-wave accelerators, all of these methods are difficult to use. In our experiments, we could not measure RF pulse shortening directly with a crystal detector because the RF pulse is very short'just a few nanoseconds'and changes in the measured signal were masked by RF amplitude jitter. To overcome this limitation, we built a single-shot spectrometer with a frequency range of 117-125 GHz and a resolution of 0.1 GHz. The spectrometer should be able to measure the widening of the spectrum caused by the shortening of nanosecond-long pulses. We present design considerations, first experimental results obtained at FACET, and planned future improvements for the spectrometer.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR056

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR059

Development of S-band High Power Load

klystron, radio-frequency, radiation, electron

383

X.C. Meng, H.B. Chen, C. Cheng, Y.-C. Du, Q. Gao, J. Shi, P. Wang, Z.F. Xiong
TUB, Beijing, People's Republic of China

Several types of S-band high power loads have been designed, manufactured and tested successfully in Tsinghua University. The high power loads, which work at 2856 MHz for 10 MW~100 MW range, are made of all stainless steel. In this paper, we will present the design, fabrication and the high power test results.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR059

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR060

C-Band Deflecting Cavity for Bunch Length Measurement of 2.5 MeV Electron Beam

cavity, electromagnetic-fields, coupling, simulation

386

J. Jiang, H.B. Chen, J. Shi, P. Wang, L. Zhang, S.X. Zheng
TUB, Beijing, People's Republic of China

The C-band deflecting cavity designed last year is finished. In this paper, the RF measurement of the cavity is introduced. After tuning, it works well at 5.712GHz with a coupling factor degree around 1.05. And we measured the electromagnetic field with bead-pull method. The flatness of the magnetic field is around 0.9, which is not ideal but meet the requirements of the bunch length measurement. And we propose a method of tuning to make sure both frequency and field flatness.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR060

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW004

Realization and High Power Tests of Damped C-Band Accelerating Structures for the ELI-NP Linac

ion, HOM, klystron, damping

399

D. Alesini, M. Bellaveglia, S. Bini, R. Boni, P. Chimenti, F. Cioeta, R.D. Di Raddo, A. Falone, A. Gallo, V.L. Lollo, L. Palumbo, S. Pioli, A. Variola
INFN/LNF, Frascati (Roma), Italy
F. Cardelli, M. Magi, A. Mostacci, L. Palumbo, L. Piersanti
University of Rome La Sapienza, Rome, Italy
F. Cardelli, L. Piersanti
INFN-Roma1, Rome, Italy
P. Favaron, F. Poletto
INFN/LNL, Legnaro (PD), Italy
L. Ficcadenti, F. Pellegrino, V. Pettinacci
INFN-Roma, Roma, Italy

The ELI-NP C-Band structures are 1.8 m long travelling wave accelerating structures, quasi-constant gradient, with a field phase advance per cell of 2pi/3. They operate at a repetition rate of 100 Hz and, because of the multi-bunch operation, they have been designed with a dipole HOM damping system to avoid beam break-up (BBU). The structures have symmetric input and output couplers and integrate, in each cell, a waveguide HOM damping systems with silicon carbide RF absorbers. An optimization of the electromagnetic and mechanical design has been done to simplify the fabrication and to reduce their cost. After the first full scale prototype successfully tested at the nominal gradient of 33 MV/m, the production of the twelve structures started. In the paper we illustrate the main design criteria, the realization process and the high power test results.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW004

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW005

Design of Linac with the New Gaskets Clamping Fabrication Technique

coupling, impedance, linac, gun

403

F. Cardelli
INFN-Roma1, Rome, Italy
D. Alesini
INFN/LNF, Frascati (Roma), Italy
M. Magi, L. Palumbo
University of Rome La Sapienza, Rome, Italy
F. Pellegrino, V. Pettinacci
INFN-Roma, Roma, Italy

Recently, a new technique for the realization of high gradient accelerating structures based on the use of gaskets without brazing processes, has been successfully tested at high power on a 1.6 cells RF gun (D. Alesini, et al, PRST 18, 02001, 2015). The new technique developed at the Laboratories of Frascati of the INFN (Italy) in the framework of the SPARC_LAB project has been also adopted for the ELI-NP RF gun. The use of the special gaskets that simultaneously guarantee the vacuum seal and a perfect RF contact allow to avoid the brazing process, strongly reducing the cost, the realization time and the risk of failure. Moreover, without copper annealing due to the brazing process, it is possible, in principle, to decrease the breakdown rate increasing, at the same time, the maximum achievable gradient. The extension of this new fabrication process to complex LINAC structures is the next step on the application of this new technique on particle accelerator. In the paper, we discuss how to extend this process to S-band and C-band Travelling Wave accelerating structures illustrating their electromagnetic design and their mechanical realization.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW005

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW007

On the Calibration Measurement of Stripline Beam Position Monitor for the ELI-NP Facility

simulation, linac, electromagnetic-fields, impedance

411

D. De Arcangelis, F. Cardelli, A. Mostacci, L. Palumbo
University of Rome La Sapienza, Rome, Italy

Stripline Beam Position Monitor (BPM) will be installed in the Compton Gamma Source in construction at the ELI Nuclear Physics facility in Romania. A test bench for the calibration of BPM has been built to characterize the device with stretched wire measurement in order to get the BPM response map. A full S-parameters characterisation is performed as well to measure the electrical offset with the "Lambertson method". This paper discusses the extensive simulations performed with full 3D electromagnetic CAD codes of the above measurements to investigate measurement accuracy, possible measurement artefacts and the beam position reconstruction.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW007

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW025

Vacuum RF Breakdown of Accelerating Cavities in Multi-Tesla Magnetic Fields

cavity, operation, Windows, electron

444

D.L. Bowring, A. Moretti, M.A. Palmer, D.W. Peterson, A.V. Tollestrup, K. Yonehara
Fermilab, Batavia, Illinois, USA
B.T. Freemire
IIT, Chicago, Illinois, USA
A.V. Kochemirovskiy
University of Chicago, Chicago, Illinois, USA
P.G. Lane, Y. Torun
Illinois Institute of Technology, Chicago, Illinois, USA

Funding: Work supported by Fermilab Research Alliance, LLC under Contract No. DE-AC02-07CH11359.
Ionization cooling of intense muon beams requires the operation of high-gradient, normal-conducting RF structures within multi-Tesla magnetic fields. The application of strong magnetic fields has been shown to lead to an increase in vacuum RF breakdown. This phenomenon imposes operational (i.e. gradient) limitations on cavities in ionization cooling channels, and has a bearing on the design and operation of other RF structures as well, such as photocathodes and klystrons. We present recent results from Fermilab's MuCool Test Area (MTA), in which 201 and 805 MHz cavities were operated at high power both with and without the presence of multi-Tesla magnetic fields. We present an analysis of damage due to breakdown in these cavities, as well as measurements related to dark current and their relation to a conceptual model describing breakdown phenomena.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW025

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW028

Progress on the MICE RF Module at LBNL

cavity, operation, coupling, experiment

454

T.H. Luo, A.J. DeMello, A.R. Lambert, D. Li, T.J. Loew, S. Prestemon, S.P. Virostek, J.G. Wallig
LBNL, Berkeley, California, USA
T.G. Anderson, A.D. Bross, M.A. Palmer
Fermilab, Batavia, Illinois, USA
Y. Torun
IIT, Chicago, Illinois, USA

The international Muon Ionization Cooling Experiment aims to demonstrate the transverse cooling of a muon beam by ionization in energy absorbers. The final MICE cooling channel configuration has two RF modules, each housing a 201 MHz RF cavity used to compensate the longitudinal energy loss in the absorbers. The assembly of MICE RF Module is being carried out at LBL. In this paper we will report the recent progress on the assembly work.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW028

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW034

Final Commissioning of the MICE RF Module Prototype with Production Couplers

cavity, operation, coupling, Windows

474

Y. Torun, P.G. Lane
Illinois Institute of Technology, Chicago, Illlinois, USA
T.G. Anderson, M. Backfish, D.L. Bowring, A. Moretti, D.V. Neuffer, D.W. Peterson, M. Popovic, K. Yonehara
Fermilab, Batavia, Illinois, USA
B.T. Freemire
IIT, Chicago, Illinois, USA
T.L. Hart
UMiss, University, Mississippi, USA
A.V. Kochemirovskiy
University of Chicago, Chicago, Illinois, USA
T.H. Luo
LBNL, Berkeley, California, USA

Funding: Supported by the US Department of Energy Office of Science through the Muon Accelerator Program.
We report operational experience from the prototype RF module for the Muon Ionization Cooling Experiment (MICE) with final production couplers at Fermilab's MuCool Test Area. This is the last step in fully qualifying the RF modules for operation in the experiment at RAL.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW034

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW040

Electron Beam Excitation of a Surface Wave in mm-Wave Open Accelerating Structures

electron, detector, experiment, simulation

494

M. Dal Forno, G.B. Bowden, C.I. Clarke, V.A. Dolgashev, M.J. Hogan, D.J. McCormick, A. Novokhatski, B.D. O'Shea, S.G. Tantawi, S.P. Weathersby
SLAC, Menlo Park, California, USA
B. Spataro
INFN/LNF, Frascati (Roma), Italy

Funding: Work supported by the US DOE under contract DE-AC02-76SF00515.
As part of research on the physics of rf breakdowns we performed experiments with high gradient traveling-wave mm-wave accelerating structures. The accelerating structures are open, composed of two identical halves separated by an adjustable gap. The electromagnetic fields are excited by an ultra-relativistic electron beam. We observed that a confined travelling-wave mode exists in half of the accelerating structure. The experiments were conducted at FACET facility at SLAC National Accelerator Laboratory. Depending on the gap width, the accelerating structure had beam-synchronous frequencies that vary from 90 to 140 GHz. When we opened the gap by more than half wavelength the synchronous wave remains trapped. Its behavior is consistent with the so called "surface wave". We characterized this beam-wave interaction by several methods: measurement of the radiated rf energy with the pyro-detector, measurement of the spectrum with an interferometer, measurement of the beam deflection by using the beam position monitors and profile monitor.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW040

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW041

Measurements of RF Breakdowns in Beam Driven mm-Wave Accelerating Structures

electron, experiment, detector, collider

497

M. Dal Forno, G.B. Bowden, C.I. Clarke, V.A. Dolgashev, M.J. Hogan, D.J. McCormick, A. Novokhatski, S.G. Tantawi, S.P. Weathersby
SLAC, Menlo Park, California, USA
B. Spataro
INFN/LNF, Frascati (Roma), Italy

Funding: Work supported by the US DOE under contract DE-AC02-76SF00515
We studied the physics and properties of rf breakdowns in high gradient traveling-wave accelerating structures at 100 GHz. The structures are open, made of two halves with a gap in between. The rf fields were excited in the structure by an ultra-relativistic electron beam generated by the FACET facility at the SLAC National Accelerator Laboratory. We observed rf breakdowns generated in the presence of GV/m scale electric fields. We varied the rf fields excited by the FACET bunch by moving structure relative to the beam and by changing the gap between structure halves. Reliable breakdowns detectors allowed us to measure the rf breakdown rate at these different rf parameters. We measured radiated rf energy with a pyro-detector. When the beam was off-axis, we observed beam deflection in the beam position monitors and on the screen of a magnetic spectrometer. The measurements of the deflection allowed us to verify our calculation of the accelerating gradient.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW041

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMW043

Overview of High Power Vacuum Dry RF Load Designs

linac, klystron, accelerating-gradient, interface

504

A.K. Krasnykh, A. Brachmann, F.-J. Decker, T.J. Maxwell, J. Sheppard
SLAC, Menlo Park, California, USA

Funding: Work supported by US Department of Energy under contract DE-AC02-76SF00515
A specific feature of RF linacs based on the pulsed traveling wave (TW) mode of operation is that only a portion of the RF energy is used for the beam acceleration. The residual RF energy has to be terminated into an RF load. Higher accelerating gradients require higher RF sources and RF loads, which can stably terminate the residual RF power. This overview will outline vacuumed RF loads only. A common method to terminate multi-MW RF power is to use circulated water (or other liquid) as an absorbing medium. A solid dielectric interface (a high quality ceramic) is required to separate vacuum and liquid RF absorber mediums. Using such RF load approaches in TW linacs is troubling because there is a fragile ceramic window barrier and a failure could become catastrophic for linac vacuum and RF systems. Traditional loads comprising of a ceramic disk have limited peak and average power handling capability and are therefore not suitable for high gradient TW linacs. This overview will focus on 'vacuum dry' or 'all-metal' loads that do not employ any dielectric interface between vacuum and absorber. The first prototype is an original design of RF loads for the Stanford Two-Mile Accelerator.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW043

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY007

Mechanical Design and 3-D Coupled RF, Thermal-Structural Analysis of Normal Conducting 704 MHz and 2.1 GHz Cavities for LEReC Linac

cavity, simulation, software, operation

525

J.C. Brutus, S.A. Belomestnykh, I. Ben-Zvi, M. Blaskiewicz, J.M. Brennan, A.V. Fedotov, M.C. Grau, C. Pai, L. Snydstrup, J.E. Tuozzolo, B. P. Xiao, T. Xin, W. Xu, A. Zaltsman
BNL, Upton, Long Island, New York, USA
V. Veshcherevich
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE.
Two normal conducting cavities operating at 704 MHz and 2.1 GHz will be used for the Low Energy RHIC electron Cooling (LEReC) under development at BNL to improve RHIC luminosity for heavy ion beam energies below 10 GeV/nucleon. The single cell 704 MHz cavity and the 3-cell 2.1 GHz third harmonic cavity will be used in LEReC to correct the energy spread introduced in the SRF cavity. The successful operation of normal RF cavities has to satisfy both RF and mechanical requirements. 3-D coupled RF-thermal-structural analysis has been performed on the cavities to confirm the structural stability and to minimize the frequency shift resulting from thermal and structural expansion. In this paper, we will present an overview of the mechanical design, results from the RF-thermal-mechanical analysis, progress on the fabrication and schedule for the normal conducting RF cavities for LEReC.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY007

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY010

RF Design of Normal Conducting 704 MHz and 2.1 GHz Cavities for LEReC Linac

cavity, HOM, impedance, simulation

532

B. P. Xiao, I. Ben-Zvi, M. Blaskiewicz, J.M. Brennan, J.C. Brutus, A.V. Fedotov, H. Hahn, G.T. McIntyre, C. Pai, K.S. Smith, J.E. Tuozzolo, Q. Wu, T. Xin, W. Xu, A. Zaltsman
BNL, Upton, Long Island, New York, USA
S.A. Belomestnykh
Fermilab, Batavia, Illinois, USA
S.A. Belomestnykh, I. Ben-Zvi, T. Xin
Stony Brook University, Stony Brook, USA
V. Veshcherevich
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 and by National Energy Research Scientific Computing Center under contract No. DE-AC02-05CH11231 by US DOE.
To improve RHIC luminosity for heavy ion beam energies below 10 GeV/nucleon, the Low Energy RHIC electron Cooler (LEReC) is currently under development at BNL. Two normal conducting cavities, a single cell 704 MHz cavity and a 3 cell 2.1 GHz third harmonic cavity, will be used in LEReC for energy spread correction. Currently these two cavities are under fabrication. In this paper we report the RF design of these two cavities.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY010

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY032

Design and Upgrade the Safety System for the SRF Electronic System at the Taiwan Photon Source

SRF, cryogenics, storage-ring, PLC

567

F.-T. Chung, F.-Y. Chang, L.-H. Chang, M.H. Chang, L.J. Chen, M.-C. Lin, Z.K. Liu, C.H. Lo, C.L. Tsai, M.H. Tsai, Ch. Wang, M.-S. Yeh, T.-C. Yu
NSRRC, Hsinchu, Taiwan

This paper presents some new designs and upgrades of a SRF interlock and electronic system. Based on the experience from Taiwan Light Source (TLS) that uses one Cornell-type superconducting cavity made by ACCEL in the storage-ring RF system [1], in the new TPS SRF system [3] home-made LLRF and SRF electronics [4] are constructed for two KEKB-type superconducting cavities [2] that are installed in the storage ring of circumference 518 m. For reliable operation of the TPS SRF system, enhanced safety functions of the system were added to improve the original SRF system in TLS. The improved functions can provide both the operators and the RF systems with a safer environment and clearer messages for trouble-shooting and malfunction status indications.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY032

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY036

High-harmonic mm-Wave Frequency Multiplication using a Gyrocon-like Device

cavity, electron, coupling, plasma

579

F. Toufexis, V.A. Dolgashev, M.V. Fazio, A. Jensen, S.G. Tantawi, A.R. Vrielink
SLAC, Menlo Park, California, USA
P. Borchard
Dymenso LLC, San Francisco, USA

Funding: This project was funded by U.S. Department of Energy under Contract No. DE-AC02-76SF00515, and the National Science Foundation.
Traditional linear interaction RF sources, such as Klystrons and Traveling Wave Tubes, fail to produce significant power levels at millimeter wavelengths. This is because their critical dimensions are small compared to the wavelength, and the output power scales as the square of the wavelength. We present a vacuum tube technology, where the device size is inherently larger than the operating wavelength. We designed a low–voltage mm–wave source, with an output interaction circuit based on a spherical sector cavity. This device was configured as a phased-locked frequency multiplier. We report the design and cold test results of a proof-of-principle fifth harmonic frequency multiplier with an output frequency of 57.12 GHz.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY036

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY037

GaN Class-F Power Amplifier for Klystron Replacement

klystron, electron, operation, controls

583

A.V. Smirnov
RadiaBeam Systems, Santa Monica, California, USA
R.B. Agustsson, S. Boucher, D.I. Gavryushkin, J.J. Hartzell, K.J. Hoyt, A.Y. Murokh, T.J. Villabona
RadiaBeam, Santa Monica, California, USA

Funding: This work was supported by the U.S. Department of Energy (award No. DE-SC0013136)
The vacuum-tube-based RF amplifiers are relatively inefficient and becoming obsolete as the RF world has been progressively converting to solid state technology. Currently, the JLAB upgrade program requires 340 amplifiers capable of 8 kW CW at 1497 MHz while operating at more than 55-60% efficiency to replace their klystrons. Here we explore the possibility of a klystron replacement employing high electron mobility packaged GaN transistors applied in an array of Class-F amplifiers. The inputs and outputs of the many modules needed to make a complete amplifier are connected via precise, in-phase, low-loss, broadband, combiners-dividers. We describe early prototypes of the amplifiers as well as the combiners-dividers and discuss the design features and challenges of such a scheme. This approach can be applied to other national facilities and also for replacement of the klystrons in Middle Energy Electron-Ion Collider which requires about 1.8 MW CW power in total to be produced at 952.6 MHz frequency including 2x12.5 kW power for "crabbing" and 0.53 MW for electron cooling.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY037

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOR005

Longitudinal Wakefields in the Undulator Section of SXFEL User Facility

undulator, FEL, wakefield, electron

595

M. Song, H.X. Deng, C. Feng, D. Huang, B. Liu, D. Wang
SINAP, Shanghai, People's Republic of China

Shanghai soft x-ray free electron laser (SXFEL) user facility based on multi-stage seeded-FEL and self-amplified spontaneous emission (SASE) is recently proposed, which is aiming at generating 4-2nm fully-coherent, high-brightness FEL pulse. In this paper, the wakefields arise from the resistive wall and surface roughness in the vacuum chamber is obtained by theoretical models*. And the computations of geometric wakefields are carried out using ABCI**. According to the tracked beam profile, the overall wakefields in the undulator section of SXFEL user facility are presented.
* K. Bane, G. Stupakov, SLAC-PUB-15951, May 2014.
** ABCI website: http://abci.kek.jp/abci.htm

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR005

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOR007

Local Impedance Measurements at ALBA from Turn-by-Turn Acquisition

impedance, insertion, lattice, optics

598

M. Carlà, G. Benedetti, T.F.G. Günzel, U. Iriso, Z. Martí
ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain

A transverse impedance source manifests itself, among other ways, by producing a small defocusing kick which depends on the beam bunch charge. By repeating optics measurements for different bunch charges, it is possible to disentangle the contribution produced by each impedance source from the dominating focusing effects given by the machine optics. But hunting for such faint defocusing effects poses strong requirements on the precision and sensibility of the measurements, and slow machine drifts or different thermal conditions shall be avoided. In this report, we present a novel method to assess in a fast and precise manner machine optics for different bunch charges using BPM turn-by-turn data and hybrid filling patterns. Finally, measurements for different ALBA machine components like scrapers and In-vacuum undulators are compared with simulation results.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR007

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOR008

Beam Induced RF Heating in LHC in 2015

impedance, operation, injection, monitoring

602

B. Salvant, O. Aberle, M. Albert, R. Alemany-Fernandez, G. Arduini, J. Baechler, M.J. Barnes, P. Baudrenghien, O.E. Berrig, N. Biancacci, G. Bregliozzi, J.V. Campelo, F. Carra, F. Caspers, P. Chiggiato, A. Danisi, H.A. Day, M. Deile, D. Druzhkin, J. F. Esteban Müller, S. Jakobsen, J. Kuczerowski, A. Lechner, R. Losito, A. Masi, N. Minafra, E. Métral, A.A. Nosych, A. Perillo Marcone, D. Perini, S. Redaelli, F. Roncarolo, G. Rumolo, E.N. Shaposhnikova, J.A. Uythoven, C. Vollinger, A.J. Välimaa, N. Wang, M. Wendt, J. Wenninger, C. Zannini
CERN, Geneva, Switzerland
M. Bozzo
INFN Genova, Genova, Italy
J.F. Esteban Müller
EPFL, Lausanne, Switzerland
N. Wang
IHEP, Beijing, People's Republic of China

Following the recurrent beam induced RF issues that perturbed LHC operation during LHC Run 1, a series of actions were put in place to minimize the risk that similar issues would occur in LHC Run 2: longitudinal impedance reduction campaign and/or improvement of cooling for equipment that were problematic or at the limit during Run 1, stringent constraints enforced on new equipment that would be installed in the machine, tests to control the bunch length and longitudinal distribution, additional monitoring of temperature, new monitoring tools and warning chains. This contribution reports the outcome of these actions, both successes as well as shortcomings, and details the lessons learnt for the future runs.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR008

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOR016

Impedance Study with Single Bunch Beam at Taiwan Photon Source

impedance, photon, storage-ring, synchrotron

630

C.-C. Kuo, P.J. Chou, K.T. Hsu, K.H. Hu, C.C. Liang, C.Y. Liao, Z.K. Liu, H.-J. Tsai, F.H. Tseng
NSRRC, Hsinchu, Taiwan

The impedance at Taiwan Photon Source was investigated. The effects of bunch current such as a tune change, a synchronous phase shift and a bunch lengthening under operation conditions at various stages were measured; the machine impedances were deduced. This report presents the results with insertion devices in various configurations.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR016

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOW001

Status of the 1.3 GeV Booster Synchrotron for Generating High Energy Gamma Rays at Tohoku University

controls, dipole, operation, booster

701

F. Hinode, H. Hama, S. Kashiwagi, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi, C. Tokoku
Tohoku University, Research Center for Electron Photon Science, Sendai, Japan

The reconstruction work of accelerator complex for the Great East Japan Earthquake in March 2011 had been conducted in Research Center of Electron Photon Science, Tohoku University. Since restoration of the user machine time in 2013, the approved beam time have been regularly implemented as scheduled. Currently, the 1.3 GeV Booster STorage (BST) ring has been well utilized to generate the high energy gamma-rays as before the disaster. The high energy gamma-rays were produced via Bremsstrahlung by inserting an internal target wire to the beam orbit after the beam acceleration. Since the user machine time was recovered, there were some improvements so far, i.e. realignment of synchrotron magnets, orbit correction in energy ramping process by updating the control of power supplies for steering magnets etc., which brought an increase of the beam current in the maximum energy. Present operational status and recent progress of beam performance in the BST ring are reported.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOW001

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOW006

Planning and Controlling of the Cold Accelerator Sections Installation in XFEL

status, laser, electron, free-electron-laser

716

M. Bousonville, S. Choroba, F. Eints
DESY, Hamburg, Germany

The installation of the main linear accelerator in the 2 km European XFEL (X-Ray Free-Electron Laser) tunnel is currently under way. The accelerator consists of nine so-called cryo-strings. A typical cryo-string comprises 12 accelerator modules, which will be fed by three RF stations. Furthermore, the installation of electronic racks, cables, power and water supply etc. takes place. To enable a most effective installation of the accelerator components, planning and controlling methods, which had first been developed for the RF system work package, were adapted for the entire main linear accelerator. As a first step, a process plan was developed in cooperation with the work package leaders. On the basis of this plan, the installation process is promoted by several measures: The status of the installation is precisely registered by weekly queries which enable monitoring of the progress and feedback to everyone involved. With this information at hand, the installation process can be controlled and plan deviations can be corrected. Furthermore, the experience gained at one cryo-string is used to optimise the plan for the next cryo-string installation.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOW006

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY011

Estimating the Transverse Impedance in the Fermilab Recycler

impedance, proton, quadrupole, dipole

867

R. Ainsworth, P. Adamson, A.V. Burov, I. Kourbanis, M.-J. Yang
Fermilab, Batavia, Illinois, USA

Impedance could represent a limitation of running high intensity bunches in the Fermilab recycler. With high intensity upgrades foreseen, it is important to quantify the impedance. To do this, studies have been performed measuring the tune shift as a function of bunch intensity allowing the transverse impedance to be derived.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY011

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY024

Development of a 325 MHz Ladder-RFQ of the 4-Rod-Type

rfq, proton, linac, ion

899

M. Schütt, U. Ratzinger
IAP, Frankfurt am Main, Germany
C. Zhang
GSI, Darmstadt, Germany

In order to have an inexpensive alternative to 4-Vane RFQs above 200 MHz, we study the possibilities of a Ladder-RFQ. The 325 MHz RFQ is designed to accelerate protons from 95 keV to 3.0 MeV according to the design parameters of the research program with cooled antiprotons at FAIR. This particular high frequency for an RFQ creates difficulties, which are challenging in developing a cavity. In order to define a satisfactory geometrical configuration for this resonator, both from the RF and the mechanical point of view, different designs have been examined and compared. Very promising results have been reached with a ladder type RFQ, which has been investigated since 2013. Due to its geometric size the manufacturing as well as maintenance is not that complex compared with welded accelerators. The manufacturing, coppering and assembling of a 0.8 m prototype RFQ is finished. We present recent measurements of the rf-field, frequency-tuning, field flatness and the mode spectrum.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY024

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY040

Design of the 100 MeV Proton Beam Line for Low Flux Application

target, octupole, beam-transport, proton

938

H.-J. Kwon, Y.-S. Cho, C.R. Kim, H.S. Kim, S.G. Lee, S. Lee, S.P. Yun
Korea Atomic Energy Research Institute (KAERI), Gyeongbuk, Republic of Korea

Funding: This work was supported by the Ministry of Science, ICT & Future Planning of the Korean Government.
KOMAC has been operating two beam lines for user service since 2013. A new beam line was completed in 2015 for radioisotope production and has a plan to be commissioned in 2016. Another beam line was proposed to supply low flux beam to users. The maximum energy and average current are 100 MeV and 10 nA. The beam line consists of collimator, energy degrader, dipole magnet for energy separation and octupole magnet for uniform beam production. In this paper, the design of the beam line and its components is presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY040

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY041

Commissioning of New Proton and Light Ion Injector for Nuclotron-Nica

rfq, linac, ion, simulation

941

S.M. Polozov, V.S. Dyubkov, M. Gusarova, T. Kulevoy, A.A. Martynov, A.S. Plastun, A.V. Samoshin
MEPhI, Moscow, Russia
V. Aleksandrov, A.V. Butenko, B.V. Golovenskiy, A. Govorov, V. Kobets, A.D. Kovalenko, V. Monchinsky, V.V. Seleznev, A.O. Sidorin, G.V. Trubnikov
JINR, Dubna, Moscow Region, Russia
V. Andreev, A.I. Balabin, S.V. Barabin, V.A. Koshelev, A.V. Kozlov, G. Kropachev, R.P. Kuibeda, T. Kulevoy, V.G. Kuzmichev, D.A. Liakin, A.Y. Orlov, A.S. Plastun, D.N. Selesnev, A. Sitnikov, Yu. Stasevich
ITEP, Moscow, Russia
A.P. Durkin
MRTI RAS, Moscow, Russia
K.A. Levterov
JINR/VBLHEP, Dubna, Moscow region, Russia
S.V. Vinogradov
MIPT, Dolgoprudniy, Moscow Region, Russia

The new accelerator complex Nuclotron-based Ion Collider fAcility (NICA) is now under development and construction at JINR. New complex is assumed to operate using two injectors: the Alvarez-type linac LU-20 as injector of light ions, polarized protons and deuterons and a new linac HILac of heavy ions. Now the modernization of LU-20 is also realized and old pulse DC injector is planning to replace by RFQ linac. New RFQ linac was developed and manufactured and is now under commissioning at Nuclotron injectors hall. New results of RFQ linac resonator testing and measurements, RF power load and linac testing with deuterium and carbon beam will discuss in this report.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY041

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY049

The PXIE LEBT Design Choices

ion, rfq, ion-source, solenoid

958

L.R. Prost, A.V. Shemyakin
Fermilab, Batavia, Illinois, USA

Funding: Operated by Fermi Research Alliance, LLC, under Contract DE-AC02-07CH11359 with the United States Department of Energy
Typical front-ends of modern light-ion high-intensity accelerators typically consist of an ion source, a Low Energy Beam Transport (LEBT), a Radiofrequency Quadrupole and a Medium Energy Beam Transport (MEBT), which is followed by the main linac accelerating structures. Over the years, many LEBTs have been designed, constructed and operated very successfully. In this paper, we present the guiding principles and compromises that lead to the design choices of the PXIE LEBT, including the rationale for a beam line that allows un-neutralized transport over a significant portion of the LEBT whether the beam is pulsed or DC.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY049

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY051

Manufacturing and the LLRF Tests of the SANAEM RFQ

rfq, cavity, LLRF, simulation

964

G. Turemen, Y. Akgun, A. Alacakir, A.S. Bolukdemir, I. Kilic, B. Yasatekin
TAEK - SANAEM, Ankara, Turkey
G. Unel
UCI, Irvine, California, USA
H. Yildiz
Istanbul University, Istanbul, Turkey

Funding: Turkish Atomic Energy Authority
Turkish Atomic Energy Authority is working on building an experimental proton beamline with local resources at the Saraykoy Nuclear Research and Training Center (SANAEM). Manufacturing of the radio frequency quadrupole (RFQ) was started after the beam dynamics and 3D electromagnetic simulation studies were performed. The vanes were machined with a three axis CNC machine. A CMM was used for the acceptance tests of the vanes and also for assembling. Production and assembly results were found acceptable for this cavity, the very first one developed in Turkey. Copper plating was performed by electroplating the aluminum vanes. The plated vanes were bolted and bonded with eight screws, eight pins and two different adhesives. A silver paste was used for RF sealing and a low vapor pressure epoxy was used for vacuum isolation. First LLRF tests of the RFQ were done with a bead-pull setup and a VNA. A N-type RF coupler and a pick-up were used for the LLRF tests. Phase shift method was used for the bead-pull tests. Cavity quality factor was measured with 3dB method for different RF sealing stages. This study summarizes the machining, assembling and the first LLRF tests of the SANAEM RFQ.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY051

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY054

Status of the ESS RFQ

rfq, cavity, status, operation

974

D. Chirpaz-Cerbat, A. Albéri, A.C. Chauveau, M. Lacroix, N. Misiara, G. Perreu, O. Piquet, H. Przybilski, N. Sellami
CEA/IRFU, Gif-sur-Yvette, France
N. Berton, G. Bourdelle, M. Desmons, A.C. France, V.M. Hennion, P.-A. Leroy, B. Pottin
CEA/DSM/IRFU, France

The ESS Radio-Frequency Quadrupole (RFQ) is a 4-vanes resonant cavity designed at the frequency of 352.21 MHz. It must accelerate and bunch a 70mA proton beams from 75keV to 3.62MeV with a 4% duty cycle. The RFQ design has already been done, and documented in other papers. This one will present the global status of the RFQ, with technical solutions cho-sen for the main components (for fabrication and op-eration) and the present status of the RFQ fabrication.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY054

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY055

Technologies for Stabilizing the Dynamic Vacuum and Charge Related Beam Loss in Heavy Ion Synchrotrons

ion, heavy-ion, synchrotron, cryogenics

977

P.J. Spiller, L.H.J. Bozyk, C. Omet, I. Pongrac, St. Wilfert
GSI, Darmstadt, Germany

With increasing the intensities of heavy ion beams in synchrotrons, charge related beam loss become more and more significant. In order to reduce space charge forces and to minimize the incoherent tune spread, the charge state of heavy Ions shall be lowered. Thus the cross section for charge related beam loss is further enhanced. For the FAIR project, GSI has developed a number of different technologies to stabilize the dynamic residual gas pressure and thereby to minimize charge related beam loss at high intensity heavy ion operation. Technologies suitable for such issues are, dedicated lattice structures, cold and warm ion catchers, NEG coated and cryogenic magnet chambers and cryo-adsorption pumps.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY055

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY057

The Linear IFMIF Prototype Accelerator (LIPAC) Design Development under the European-Japanese Collaboration

rfq, SRF, linac, cryomodule

985

P. Cara, R. Heidinger
Fusion for Energy, Garching, Germany
N. Bazin, S. Chel, R. Gobin, J. Marroncle, B. Renard
CEA/DSM/IRFU, France
B. Brañas Lasala, D. Jiménez-Rey, J. Mollá, P. Méndez, I. Podadera
CIEMAT, Madrid, Spain
A. Facco, E. Fagotti, A. Pisent
INFN/LNL, Legnaro (PD), Italy
A. Kasugai, S. Keishi, S. O'hira
JAEA, Aomori, Japan
J. Knaster, A. Marqueta, Y. Okumura
IFMIF/EVEDA, Rokkasho, Japan
K. Sakamoto
QST, Aomori, Japan

The IFMIF aims to provide an accelerator-based, D-Li neutron source to produce high energy neutrons at sufficient intensity. Part of the BA agreement (Japan-EURATOM), the goal of the IFMIF/EVEDA project is to work on the engineering design of IFMIF and to validate the main technological challenges which includes a 125mA CW D⁺ accelerator up to 9 MeV mainly designed and manufactured in Europe. The components are in an advanced stage of manufacturing. The first components which allow the production of a 140 mA-100 keV deuteron beam have been delivered, installed and under commissioning at Rokkasho. The second phase (100 keV to 5 MeV) will end by March 2017. The third phase (short pulse) and forth phase (cw) will be the integrated commissioning of the LIPAc up to 9 MeV. The duration of the project has been recently extended up to end 2019 to allow the commissioning and operation of the whole accelerator (1MW). The aim of this paper is to give an overview of the LIPAc, currently under commissioning in Japan, to outline the engineering design and the development of the key components, as well as the expected outcomes of the engineering work, associated with the experimental program.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY057

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY058

Removing Known SPS Intensity Limitations for High Luminosity LHC Goals

impedance, simulation, emittance, shielding

989

E.N. Shaposhnikova, T. Argyropoulos, T. Bohl, P. Cruikshank, B. Goddard, T. Kaltenbacher, A. Lasheen, J. Perez Espinos, J. Repond, B. Salvant, C. Vollinger
CERN, Geneva, Switzerland

In preparation of the SPS as an LHC injector its impedance was significantly reduced in 1999 - 2000. A new SPS impedance reduction campaign is planned now for the High Luminosity (HL)-LHC project, which requires bunch intensities twice as high as the nominal one. One of the known intensity limitations is a longitudinal multi-bunch instability with a threshold 3 times below this operational intensity. The instability is presently cured using the 4th harmonic RF system and controlled emittance blow-up, but reaching the HL-LHC parameters cannot be assured without improving the machine impedance. Recently the impedance sources responsible for this instability were identified and implementation of their shielding and damping is foreseen during the next long shutdown (2019 - 2020) in synergy with two other important upgrades: amorphous carbon coating of (part of) the vacuum chamber against the e-cloud effect and rearrangement of the 200 MHz RF system. In this paper the strategy of impedance reduction is presented together with beam intensity achievable after its realisation. The potential effect of other proposals on remaining limitations is also considered.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY058

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOBA01

Beam Commissioning of SuperKEKB

optics, coupling, detector, septum

1019

Y. Funakoshi, T. Abe, T. Adachi, K. Akai, Y. Arimoto, K. Egawa, Y. Enomoto, J.W. Flanagan, H. Fukuma, K. Furukawa, N. Iida, H. Iinuma, H. Ikeda, T. Ishibashi, M. Iwasaki, T. Kageyama, H. Kaji, T. Kamitani, T. Kawamoto, S. Kazama, M. Kikuchi, T. Kobayashi, K. Kodama, H. Koiso, M. Masuzawa, T. Mimashi, T. Miura, F. Miyahara, T. Mori, A. Morita, S. Nakamura, T.T. Nakamura, H. Nakayama, T. Natsui, M. Nishiwaki, K. Ohmi, Y. Ohnishi, T. Oki, S. Sasaki, M. Satoh, Y. Seimiya, K. Shibata, M. Suetake, Y. Suetsugu, H. Sugimoto, M. Tanaka, M. Tawada, S. Terui, M. Tobiyama, S. Uehara, S. Uno, X. Wang, K. Watanabe, Y. Yano, S.I. Yoshimoto, R. Zhang, D. Zhou, X. Zhou, Z.G. Zong
KEK, Ibaraki, Japan
D. El Khechen
LAL, Orsay, France

In this report, we describe the machine operation in the first 3 months of the Phase 1 commissioning of SuperKEKB. The beam commissioning is smoothly going on. Vacuum scrubbing, the optics corrections and others are described.

Slides TUOBA01 [9.346 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUOBA01

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUZB02

Challenge of In-vacuum and Cryogenic Undulator Technologies

undulator, cryogenics, radiation, permanent-magnet

1080

J.C. Huang, C.-H. Chang, C.H. Chang, T.Y. Chung, C.-S. Hwang, C.K. Yang, Y.T. Yu
NSRRC, Hsinchu, Taiwan
H. Kitamura
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan

An in-vacuum undulator (IVU) opens the utilization of high-brilliance X-rays in the medium energy storage rings. The development of a short-period undulator with low phase error becomes important to bring X-ray into a new unprecedented brilliant light source in an ultimate storage ring (USR). NdFeB or PrFeB cryogenic permanent magnet undulators (CPMUs) with a short period have been developed worldwide to obtain high brilliance of undulator radiation. A CPMU has high resistance against beam-induced heat load and allow to operate at a narrow gap. In a low emittance or ultimate storage ring, not only the performance of an undulator but the choice of the lattice functions is very important to obtain high bril-liance of synchrotron radiation. The optimum betatron functions and zero dispersion function shall be given for a straight section at IVU/CPMUs. In this paper, the relevant factors and design issues for IVU/CPMU will be discussed. Many technological challenges of a short-period undulator associated with beam induced-heat load, phase errors, and the deformation of in-vacuum girders will also be presented herein.

Slides TUZB02 [5.204 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUZB02

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOCB01

First Commissioning of the SuperKEKB Vacuum System

electron, photon, status, positron

1086

Y. Suetsugu, H. Hisamatsu, T. Ishibashi, K. Kanazawa, K. Shibata, M. Shirai, S. Terui
KEK, Ibaraki, Japan

The SuperKEKB, an electron-positron collider with asymmetric energies in KEK, has started the first commissioning with beams this year. One of major tasks in the commissioning is the beam scrubbing of new beam pipes in order to increase the beam lifetime and to decrease the background noise of the particle detector in the coming physics run. The temperatures and the vacuum pressures of new vacuum components, such as the bellows chambers, gate valves and the beam collimators, should be checked in this run. The decrease rate in the vacuum pressure are measured to estimate the vacuum scrubbing effect. Reported here will be the results obtained during the first commissioning and the present status of the vacuum system.

Slides TUOCB01 [2.526 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUOCB01

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB012

Optimization of the Field Integrals of Two Small Gap IDs for CLS

multipole, wiggler, undulator, synchrotron-radiation

1133

M.F. Qian, Y.Z. He, H.F. Wang, W. Zhang, Q.G. Zhou
SINAP, Shanghai, People's Republic of China

An in-vacuum undulator and an in-vacuum wiggler have been developed for CLS at SSRF recently. The period lengths of the undulator and the wiggler are 20mm and 80mm respectively. Both IDs have the minimum gap of 5.2mm. The field integrals were measured for each magnet block with two poles and were sorted in-situ as they were installed on to the girders. Finally the field integrals of the undulator and the wiggler were shimmed by using the 'Magic Fingers' at the ends with a special algorithm. This paper reports the procedure and the results of the measurement and the optimization for the field integrals.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB012

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB017

The Injection Septum Magnet for the Collector Ring (FAIR)

injection, septum, operation, lattice

1145

P.Yu. Shatunov, D.E. Berkaev, I. Koop, E.P. Semenov, D.B. Shwartz
BINP SB RAS, Novosibirsk, Russia
A. Dolinskyy, S.A. Litvinov
GSI, Darmstadt, Germany
Yu. A. Rogovsky
Budker INP & NSU, Novosibirsk, Russia

Collector Ring is one of the key installations of the FAIR project (Darmstadt, Germany). It is dedicated for stochastic cooling of incoming beams of antiprotons and rare ions. Additionally there is a mode of operation for experiments in the ring. Beams for all modes of operation are injected through one transfer channel. Extremely high acceptance of the ring (240 mm*mrad) leads to large apertures of all magnetic elements including the septum magnet. Meanwhile planned parameters of the magnetic field and magnetic field quality are comparatively strict. The present state of the design of the pulsed injection septum for the CR is presented in this article together with the concept of the injection system.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB017

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB026

Magnet System for a Compact Microtron

microtron, permanent-magnet, electron, operation

1164

S.A. Kahn, R.J. Abrams, M.A.C. Cummings, R.P. Johnson, G.M. Kazakevich
Muons, Inc, Illinois, USA

Funding: Funded by DOE SBIR grant DE-SC0013795
A compact microtron can be an effective gamma source that can be transported to locations outside the laboratory. As part of a Phase I project we have studied a portable microtron that can accelerate electrons with energies of 6 MeV and above as a source for gamma and neutron production. The mass of the magnet is a significant contribution to the overall mass of the system. This paper will discuss conceptual designs for both permanent magnet and electromagnet systems. The choice of mictrotron RF frequency range is determined by the application requirements. The RF frequency influences the size of the microtron magnet and consequently its weight. We have looked at how the design would vary with the different frequency configurations.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB026

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB034

Design and Manufacture of a Superconducting Solenoid for D-Line of J-PARC Muon Facility

solenoid, operation, interface, radiation

1177

T. Semba, Y. Hagiwara, S. Kido, S. Nakajima, Y. Tanaka
Hitachi Ltd., Ibaraki-ken, Japan
N. Kawamura, Y. Makida, Y. Miyake, H. Ohhata, K. Sasaki, K. Shimomura
KEK, Ibaraki, Japan
N. Kurosawa
KEK, Tokai Branch, Tokai, Naka, Ibaraki, Japan
Y. Murata
Hitachi, Ltd., Energy and Environmental System Laboratory, Hitachi-shi, Japan
P. Strasser
High Energy Accelerator Research Organization (KEK), Institute of Materials Structure Science (IMSS), Ibaraki, Japan

A superconducting solenoid for J-PARC muon facility was newly designed and manufactured. High Energy Accelerator Research Organization (KEK) has been operating the J-PARC Muon Science Establishment (MUSE) since 2008. Among its four muon beam lines, the decay muon line (D-Line) has been extracting and providing surface muons and positive decay muons up to a momentum of 50 MeV/c for various users, utilizing a superconducting solenoid. The D-Line as well as the other J-PARC facility suffered severe damages from the earthquake on March 11, 2011. It necessitated rebuilding of the damaged superconducting solenoid. New design parameter of the solenoid is as follows: length of solenoid: 6 m, diameter of warm bore: 0.2 m, magnetic field of bore center: 3.5 T, rated current: 415 A, superconducting wire: NbTi/Cu, quench protection: quench back heaters. The six-meter-long solenoid consists of twelve pieces of 0.5-meter-long superconducting coils. The entire solenoid is forced-indirectly cooled by supercritical helium flow. This report describes the design and manufacturing process of the newly built superconducting solenoid for D-Line of J-PARC muon facility.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB034

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB049

Development of Separator Cooling System for Helium

cryogenics, experiment, radiation, controls

1209

W.R. Liao, S.-H. Chang, W.-S. Chiou, P.S.D. Chuang, F. Z. Hsiao, H.C. Li, T.F. Lin, H.H. Tsai
NSRRC, Hsinchu, Taiwan

A helium phase separator with a condenser is under fabrication and assembled at National Synchrotron Radiation Research Centre (NSRRC). The objective of a helium phase separator with its condenser is to separate two-phase helium flow and to re-condense vaporized gaseous helium with a cryocooler of Gifford-McMahon type. We developed a 100 litre (ltr) helium phase separator with a small heat loss as a prototype. The experimental results for the total cooling capacity of the phase separator are 0.73 W at 1.67 bara, which includes the effect of thermal conduction and thermal radiation from the environment. The helium liquefaction rate is 2 ltr/day with a 100 ltr vessel. The mechanism of heat transfer in phase separator was investigated and discussed. This paper presents the experiment of helium liquefaction process of 100 ltr separator with condenser, which was a key component of the helium phase separator.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB049

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB050

Development of Multi-channel Line for the NSRRC Cryogenic System

cryogenics, radiation, photon, synchrotron

1212

P.S.D. Chuang, S.-H. Chang, W.-S. Chiou, F. Z. Hsiao, H.C. Li, W.R. Liao, T.F. Lin, H.H. Tsai
NSRRC, Hsinchu, Taiwan

For the past few years, the technology of X-ray photon source is getting more and more advanced, more and more countries are now striving to build the biggest synchrotron facility to meet its' need. In Taiwan, the construction of an electron accelerator with the energy of up to 3.5 GeV is constructed to fulfill the strong demands for an X-ray photon source with high brilliance and flux. Thus, to let the TPS be under stable operation, the cryogenic system is therefore very important. The refrigerant of the TPS Cryogenic System is Liquid Helium, to maintain liquid helium in its state, the temperature has to be maintained under 4.5K, however to let liquid helium turn into gas helium, only 20 W is needed. Therefore, the Multi-Channel Line is developed in our system to prevent heat from conduction in and letting liquid helium vaporize. Several mechanical parts have been designed to reduce heat loss and meet its needs, for example the Spacer. The paper presents a design methodology of long multi-channel helium cryogenic transfer lines. It describes some aspects thermo-mechanical calculation, supporting structure and contraction protection.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB050

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR002

Suppression of Concomitant Flow of Charged Particles in the Tandem Accelerator with Vacuum Insulation

ion, electron, proton, neutron

1225

S.Yu. Taskaev, D.A. Kasatov, A.N. Makarov, Y.M. Ostreinov, I.M. Shchudlo, I.N. Sorokin
BINP SB RAS, Novosibirsk, Russia

Funding: The study was supported by the Grants from the Russian Science Foundation (Project no. 14-32-00006) and the Budker Institute of Nuclear Physics.
A source of epithermal neutrons based on a tandem accelerator with vacuum insulation for Boron Neutron Capture Therapy of malignant tumors was proposed and constructed. Stationary proton beam with 2 MeV energy, 1.6 mA current, 0.1% energy monochromaticity and 0.5% current stability was obtained*. The flow of charged particles accompanying the accelerated ion beam was detected and measured**. To suppress this concomitant flow cooled diaphragm, cryopump and the electrostatic ring were installed in the input of accelerator. The surface of the vacuum vessel was covered with netting to suppress secondary electron emission. These steps have reduced the flow of charged particles 25 % of the ion beam to 0.5 % and to increase the current proton beam 3 times - up to 4.5 mA. The paper presents the results of research and declares plans to use the accelerator for the BNCT.
* D. Kasatov, et al. JINST 9 (2014) P12016.
** D. Kasatov, et al. Technical Physics Letters 41 (2015) 139-141.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR002

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR003

Three-fold Increase of the Proton Beam Current in the Vacuum Insulation Tandem Accelerator

ion, proton, tandem-accelerator, electron

1228

I.M. Shchudlo, V. Dokutovich, D.A. Kasatov, A.N. Makarov, I.N. Sorokin, S.Yu. Taskaev
BINP SB RAS, Novosibirsk, Russia

Funding: The study was supported by the Grants from the Russian Science Foundation (Project no. 14-32-00006) and the Budker Institute of Nuclear Physics
In BINP neutron source for boron neutron capture therapy of cancer based on the vacuum insulation tandem accelerator and lithium target for neutron generation was constructed. After optimization of the injection of negative hydrogen ions and modernization of the stripping target 1.6 mA 2 MeV proton beam was obtained. Improvements of the accelerator to suppress accompanying electron current were introduced, and after making changes to protection system of high voltage power supply a stable proton beam with a current of 4.5 mA was obtained. Analysis of the experimental results shows that the beam is accelerated without losses. Obtaining of proton beam with the current of more than 3 mA offers the prospects of using of accelerators for BNCT in cancer clinics.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR003

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR006

The ELENA Electron Cooler

electron, gun, solenoid, antiproton

1236

G. Tranquille, J. Cenede, A. Frassier, L.V. Jørgensen, A.J. Kolehmainen, B. Moles, M.A. Timmins
CERN, Geneva, Switzerland

The ELENA (Extra Low ENergy Antiproton) ring will deliver antiprotons at an energy of just 100 keV to experiments aiming to precisely measure the properties of anti-hydrogen atoms. A crucial component of this decelerator ring is the electron cooler which will be used to counter the beam blow-up as the antiproton energy is reduced from 5.3 MeV to 100 keV. The electron cooler will operate at energies below 350 eV in a longitudinal guiding field of 100 G such that the perturbations to the ring can be easily corrected. We will present the design considerations as well as the production status of the cooler.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR006

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR029

Advanced EBIS Charge Breeder for Rare Isotope Science Project

electron, ion, gun, solenoid

1304

S.A. Kondrashev, J.-W. Kim, Y.H. Park
IBS, Daejeon, Republic of Korea
H.J. Son
Handong Global University, Pohang, Republic of Korea

Rare Isotope Science Project (RISP) is under development in Korea to provide wide variety of intense rare isotope beams for nuclear physics experiments and applied science using both Isotope Separation On-Line (ISOL) and In-Flight Fragmentation (IF) techniques. Electron Beam Ion Source (EBIS) charge breeder is a key element to efficiently accelerate rare isotope ion beams produced by ISOL method. These beams will be charge-bred by an EBIS charge breeder to a charge-to-mass ratio (q/A) ≥ - and accelerated by linac post-accelerator to energies of 18.5 MeV/u. Utilization of 3 A electron beam and 6 T superconducting solenoid with wide (8) warm bore diameter will allow high efficient and fast charge breeding of rare isotope beams with exceptional degree of purity. The main features of RISP EBIS charge breeder design and current status of the project will be presented and discussed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR029

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR030

Progress on RFQ Fabrication for RISP Accelerator

rfq, alignment, cavity, laser

1308

B.-S. Park, B.H. Choi, I.S. Hong
IBS, Daejeon, Republic of Korea

The 81.25MHz Radio Frequency Quadrupole(RFQ), which was designed to accelerate various ion beams from the energy of 10 keV/u to 500 keV/u, is under development for the Rare Isotope Science Project(RISP). The 5 meter long RFQ consists of 9 sections and the total weight is roughly 16 tons. Each sections of RFQ aligned and installed by using a laser tracker on a supporter system. In this paper, the fabrication status of the RISP RFQ and the scheme of installation were described in detail.
This work was supported by the RISP of IBS funded by the Ministry of Science, ICT and Future Planning(MSIP) and the National Research Foundation(NRF) of Korea(2013M7A1A1075764).

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR030

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR033

Low Emittance Growth in a LEBT with Un-neutralized Section

ion, ion-source, emittance, solenoid

1317

L.R. Prost, J.-P. Carneiro, A.V. Shemyakin
Fermilab, Batavia, Illinois, USA

Funding: Operated by Fermi Research Alliance, LLC, under Contract DE-AC02-07CH11359 with the United States Department of Energy
In a Low Energy Beam Transport line (LEBT), the emittance growth due to the beam's own space charge is typically suppressed by way of neutralization from either electrons or ions, which originate from ionization of the background gas. In cases where the beam is chopped, the neutralization pattern changes throughout the beginning of the pulse, causing the Twiss parameters to differ significantly from their steady state values, which, in turn, may result in beam losses downstream. For a modest beam perveance, there is an alternative solution, in which the beam is kept un-neutralized in the portion of the LEBT that contains the chopper. The emittance can be nearly preserved if the transition to the un-neutralized section occurs where the beam exhibits low transverse tails. This report discusses the experimental realization of such a scheme at Fermilab's PXIE, where low beam emittance dilution was demonstrated

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR033

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR040

The Development of a New Low Field Septum Magnet System for Fast Extraction in Main Ring of J-PARC

septum, operation, power-supply, extraction

1340

T. Shibata, K. Ishii, H. Matsumoto, N. Matsumoto, T. Sugimoto
KEK, Ibaraki, Japan
K. Fan
HUST, Wuhan, People's Republic of China

The J-PARC Main Ring (MR) is being upgraded to improve its beam power to the design goal of 750 kW. One important way is to reduce the repetition period from 2.48 s to 1.3 s so that the beam power can be nearly doubled. We need to improve the septum magnets for fast extraction. We are improving the magnets and their power supplies. The present magnets which is conventional type have problem in durability of septum coil by its vibration, and large leakage field. The new magnets are eddy current type. The eddy current type does not have septum coil, but has a thin plate. We expect that there is no problem in durability, we can construct the thin septum plate, the leakage field can be reduced. The output of the present power supply are pattern current which of flat top is 10 ms width, the new one is short pulse which of one is 10 us. The short pulse consists of 1st and 3rd higher harmonic. We can expect that the flatness and reproducibility of flat top current can be improved. The calorific power can be also reduced. This paper will report the field measurement results with the eddy septum magnet systems.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR040

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR044

Beam Test of the New Beamline for Radio-Isotope Production at KOMAC

target, linac, isotope-production, proton

1349

H.S. Kim
KAERI, Daejon, Republic of Korea
Y.-S. Cho, H.-J. Kwon, S.P. Yun
Korea Atomic Energy Research Institute (KAERI), Gyeongbuk, Republic of Korea

Funding: This work has been supported through KOMAC (Korea Multi-purpose Accelerator Complex) operation fund of KAERI by MSIP (Ministry of Science, ICT and Future Planning).
A high power proton linac is under operation at Korea multi-purpose accelerator complex (KOMAC). Currently, two beamlines are available and used to provide 20-MeV beam and 100-MeV beam to users from various fields. An additional 100-MeV beamline has been constructed mainly for production of radio-isotopes such as Sr-82 and Cu-67. Proton beam with the beam energy of 100 MeV and the average current of 0.6 mA is directed to the production target, which is located in a water-filled target chamber, through a beam window made of AlBeMet. The beam size at the target is designed to be about 100 mm in diameter. Installation of the beamline components including 1.5 T bending magnet and the beam diagnostic devices such as BPM and BCM is finished and beam commissioning is planned to start in early 2016. The details of newly-constructed beamline and the initial beam test results will be given in this paper.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR044

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR053

Initial Experience with Carbon Stripping Foils at ISIS

injection, operation, synchrotron, proton

1378

B. Jones, D.J. Adams, H. V. Smith
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

The ISIS Facility at the Rutherford Appleton Laboratory is a spallation neutron and muon source based upon a 50 Hz rapid cycling synchrotron accelerating ~3×10¹³ protons per pulse from 70 to 800 MeV to deliver a mean beam power of 0.2 MW to two target stations. Throughout its 30 years of operation ISIS has developed aluminium oxide foils in-house for H− charge exchange injection. The manufacturing and installation processes for these foils are time consuming, radiologically dose intensive and require a high degree of skill. Commercially available carbon based foils commonly used at other facilities, have the potential to greatly simplify foil preparation and installation in addition to improving beam quality. Similar foils would also be necessary for facility upgrades which increase injection energy to withstand the higher operating temperatures. This paper describes the initial experience of carbon foils in the ISIS synchrotron including issues relating to handling and mounting foils, their performance under beam operation and plans for further development.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR053

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMW021

Roman Pot Insertions in High-Intensity Beams for the CT-PPS Project at LHC

insertion, impedance, proton, luminosity

1473

M. Deile, R. Bruce, A. Mereghetti, D. Mirarchi, S. Redaelli, B. Salvachua, B. Salvant, G. Valentino
CERN, Geneva, Switzerland

The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) at the LHC IP5 aims at exploring diffractive physics at high luminosity in standard LHC fills. It is based on 14 Roman Pots (RPs), designed to host tracking and time-of-flight detectors for measuring the kinematics of leading protons. To reach the physics goals, the RPs will finally have to approach the beams to distances of 15 beam σs (i.e. ~1.5 mm) or closer. After problems with showers and impedance heating in first high-luminosity RP insertions in 2012, the LS1 of LHC was used for upgrades in view of impedance minimisation and for adding new collimators to intercept RP-induced showers. In 2015 the effectiveness of these improvements was shown by successfully inserting the RPs in all LHC beam intensity steps to a first-phase distance of ~25 σs. This contribution reviews the measurements of debris showers and impedance effects, i.e. the data from Beam Loss Monitors, beam vacuum gauges and temperature sensors. The dependences of the observables on the luminosity are shown. Extrapolations to L=10³⁴ cm^-2 s^-1 and smaller distances to the beam do not indicate any fundamental problems. The plans for 2016 are outlined.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW021

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY017

Laser Driven Dielectric Accelerator in the Non-relativistic Energy Region

laser, acceleration, electron, radiation

1585

K. Koyama, M. Uesaka
The University of Tokyo, Nuclear Professional School, Ibaraki-ken, Japan
S. Kurimura
NIMS, Ibaraki, Japan
H. Okamoto, S. Otsuki
The University of Tokyo, Tokyo, Japan
M. Yoshida
KEK, Ibaraki, Japan

Laser-driven dielectric accelerator (LDA) is suitable for delivering a submicron-size ultra-short electron beam, which is useful for studying basic processes of the radiation effect in a biological cell. Both the oblique incidence and the normal incidence configurations of LDA were studied. The oblique incidence configuration of LDA relaxes the synchronization condition as v_e=¥pm c L_G/¥left(¥λ+ L_G n ¥sin ¥theta ¥right) and is somewhat suitable for accelerating the non-relativistic electrons. The required energy to accelerate electrons in the oblique incidence configuration is smaller than that in the normal incidence configuration by a factor of ¥cos ¥theta, where ¥theta is the incidence angle of the laser beam. Two gratings each were made of different material structure of silica ({¥rm SiO₂}) were fabricated by the electron beam lithography. When a crystal silica was adopted, many large humps of several hundred nm size were observed in grooves of the grating. On the other hand, a glass silica had smoother grooves.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY017

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY032

Radiation from Open Ended Waveguide with a Dielectric Loading

radiation, electron, controls, simulation

1617

S.N. Galyamin, A.A. Grigoreva, A.V. Tyukhtin, V.V. Vorobev
Saint-Petersburg State University, Saint-Petersburg, Russia
S. Baturin
LETI, Saint-Petersburg, Russia
S. Baturin
Euclid TechLabs, LLC, Solon, Ohio, USA

Funding: Work is supported by the Grant of the President of Russian Federation (No. 6765.2015.2) and the Grants from Russian Foundation for Basic Research (No. 15-32-20985, 15-02-03913).
Terahertz radiation is considered as a promising tool for a number of applications. One possible way to emit THz waves is to pass short electron bunch through a waveguide structure loaded with dielectric*. In our previous papers, we have analyzed this problem in both approximate** and rigorous*** formulation. However, we have encountered certain difficulties with calculations. In the present report, we are starting to develop another rigorous approach based on mode-matching technique and modified residue-calculus technique. We consider the radiation from the open-ended dielectrically loaded cylindrical waveguide placed inside regular cylindrical waveguide with larger radius. We present structure of reflected and transmitted modes and typical radiation patterns from the open end of larger radius waveguide.
* S. Antipov et al., Appl. Phys. Lett., vol. 100, p. 132910, 2012.
** S.N. Galyamin et al., Opt. Express, vol. 22, No. 8, p. 8902, 2014.
*** S.N. Galyamin et al., in Proc. IPAC'15, pp. 2578-2580.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY032

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY033

Radiation of Charged Particle Flying into Chiral Isotropic Medium

polarization, radiation, plasma, interface

1620

S.N. Galyamin, A.V. Tyukhtin
Saint-Petersburg State University, Saint-Petersburg, Russia
A.A. Peshkov
HIJ, Jena, Germany

Funding: Work is supported by the Grant of the Russian Foundation for Basic Research (No. 15-32-20985).
In recent years, the interest to radiation of moving charged particles in media with chiral properties is connected with relatively new and prospective method for diagnostics of biological objects which uses the Cherenkov radiation ' Cherenkov luminescence imaging*. Optical activity (chirality, gyrotropy) is typical or biological matter and is caused by mirrorless structure of molecules. Contrary to such gyrotropic medium as magnetized ionospheric plasma, aforementioned media are isotropic. One distributed model describing the frequency dispersion of isotropic chiral media is Condon model. In this report, we continue the investigation performed in our previous paper** where we dealt with the field produced by uniformly moving charge in infinite chiral isotropic medium. Moreover, we perform generalization of early paper***, where the problem with half-space was considered in the specific case of slow charge motion. We present typical radiation patterns in vacuum area and corresponding ellipses of polarization which allows determination of the chiral parameter of the medium.
* Spinelli A.E. et al. // NIM A. 2011. V. 648. P. S310.
** Galyamin S.N. et al. // Phys. Rev. E. 2013. V. 88. P. 013206.
*** Engheta N., Mickelson A.R. // IEEE Trans. AP. 1982. V. 30. P. 1213.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY033

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY034

On Bunch Diagnostics with use of Surface Waves Generated on Planar Wire Grid

radiation, electronics, diagnostics, electromagnetic-fields

1623

V.V. Vorobev, S.N. Galyamin, A.V. Tyukhtin
Saint-Petersburg State University, Saint-Petersburg, Russia

Funding: Work is supported by the Grant of the President of Russian Federation (No. 6765.2015.2) and the Grants from Russian Foundation for Basic Research (No. 15-32-20985, 15-02-03913).
Periodic structures can be used for non-destructive diagnostics of charged particle bunches*. We consider structures which consist of thin conducting parallel wires. It is assumed that the structure period is much less than the typical wavelength under consideration. Therefore the influence of the structure on the electromagnetic field can be described with help of the averaged boundary conditions**. We consider radiation of bunches which move along the grid but transversely to wires. Unlike previous works the bunch is assumed to have essential transversal dimensions along with definite longitudinal charge distribution. In particular we analyze the effect of reflection of the surface wave from the structure edge. For all considered situations, analytical and numerical results demonstrate that analysis of the surface waves allows estimating the size and the shape of the bunch.
* A.V. Tyukhtin et al., Phys. Rev. ST AB 17, 122802 (2014); A.V. Tyukhtin et al., Phys. Rev. E 91, 063202 (2015).
** M.I. Kontorovich et al., Electrodynamics of Grid Structures (Moscow, 1987).

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY034

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY035

Short-wavelength Radiation of a Small Charged Bunch in Presence of a Dielectric Prism

radiation, target, optics, polarization

1626

A.V. Tyukhtin, S.N. Galyamin
Saint-Petersburg State University, Saint-Petersburg, Russia
E.S. Belonogaya
LETI, Saint-Petersburg, Russia

Funding: Work is supported by the Grant from Russian Foundation for Basic Research (No. 15-02-03913).
Investigation of radiation of a charged particle bunch in the presence of a large (compared with wavelengths under consideration) dielectric object can be performed using certain approximate methods. We develop here the method based on the known Stratton-Chu formulae which allows calculating the field everywhere outside the object including the Fresnel and Fraunhofer areas, as well as neighborhoods of focal points*. The main problem considered here consists in investigation of radiation of a small bunch moving along boundary of a dielectric prism or in channel inside a prism. Approximate analytical solutions of the problem are obtained and typical numerical results are given.
*S.N. Galyamin and A.V. Tyukhtin, Phys. Rev. Lett. 113, 064802, 2014.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY035

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY041

Delivery Status of the ELI-NP Gamma Beam System

gun, solenoid, laser, linac

1635

S. Tomassini, D. Alesini, A. Battisti, R. Boni, F. Cioeta, A. Delle Piane, E. Di Pasquale, G. Di Pirro, A. Falone, A. Gallo, S.I. Incremona, V.L. Lollo, A. Mostacci, S. Pioli, R. Ricci, U. Rotundo, A. Stella, C. Vaccarezza, A. Vannozzi, A. Variola
INFN/LNF, Frascati (Roma), Italy
A. Bacci, D.T. Palmer, L. Serafini
Istituto Nazionale di Fisica Nucleare, Milano, Italy
N. Bliss
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
F. Cardelli
INFN-Roma1, Rome, Italy
K. Cassou, Z.F. Zomer
LAL, Orsay, France
G. D'Auria
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
A. Giribono, V. Pettinacci
INFN-Roma, Roma, Italy
C. Hill
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
L. Palumbo
Rome University La Sapienza, Roma, Italy
L. Piersanti
University of Rome La Sapienza, Rome, Italy

The ELI-NP GBS is a high intensity and monochromatic gamma source under construction in Magurele (Romania). The design and construction of the Gamma Beam System complex as well as the integration of the technical plants and the commissioning of the overall facility, was awarded to the Eurogammas Consortium in March 2014. The delivery of the facility has been planned in for 4 stages and the first one was fulfilled in October 31st 2015. The engineering aspects related to the delivery stage 1 are presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY041

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOR008

Effect of the Various Impedances on Longitudinal Beam Stability in the CERN SPS

impedance, HOM, simulation, operation

1666

A. Lasheen, T. Argyropoulos, J. Repond, E.N. Shaposhnikova
CERN, Geneva, Switzerland

The High Luminosity (HL)-LHC project at CERN aims at a luminosity increase by a factor ten and one of the necessary ingredients is doubling the bunch intensity to 2.4x10¹¹ ppb for beams with 25 ns bunch spacing. Many improvements are already foreseen in the frame of the LHC Injector Upgrade (LIU) project, but probably this intensity would still not be reachable in the SPS due to longitudinal instabilities. Recently a lot of effort went into finding the impedance sources of the instabilities. Particle simulations based on the latest SPS impedance model are now able to reproduce the measured instability thresholds and were used to determine the most critical impedance sources by removing them one by one from the model. It was found that impedance of vacuum flanges and of the already damped 630 MHz HOM of the main RF system gave for 72 bunches the comparable intensity thresholds. Possible intensity gains are defined for realistic impedance modifications and for various beam configurations (number of bunches, longitudinal emittances) and RF programs (single and double RF). The results of this study are used as a guideline for planning of a new campaign of the SPS impedance reduction.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR008

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOR011

Study of Microwave Instability for SLS-2

impedance, storage-ring, emittance, simulation

1678

H.S. Xu, P. Craievich, M.M. Dehler, L. Stingelin
PSI, Villigen PSI, Switzerland

An ultra-low emittance electron storage ring is under development for the Upgrade of Swiss Light Source (SLS-2). An antechamber scheme consisting of round beam channel with 10 mm inner radius is considered to accommodate the required strong quadrupole and sextupole magnets, achieve the ultra-high vacuum, and absorb the undesired synchrotron radiation. However, the small size of vacuum chamber increases the susceptibility of the beam to the impedance induced collective instabilities. We will present the preliminary study of the microwave instability for SLS-2 storage ring considering the longitudinal Resistive-Wall (RW) impedance due to three different options for the beam chamber. The microwave instability thresholds are calculated under the conditions of two possible RF frequencies (100 MHz and 500 MHz) and three different materials (aluminum, copper, and stainless steel). The influences of third-harmonic cavities are also studied.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR011

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOR023

Investigation of Trapped Resonant Modes in Insertion Devices at the Australian Synchrotron

resonance, feedback, undulator, synchrotron

1710

R.T. Dowd, M.P. Atkinson, M.J. Boland, G. LeBlanc, Y.E. Tan
SLSA, Clayton, Australia
D. Teytelman
Dimtel, San Jose, USA

The Australian Synchrotron light Source has 3 variable gap in-vacuum undulators (IVU) in the storage ring. Since installation, these devices have been the source of strong beam instabilities. These instabilities seem to behave as trapped resonant modes of very high Q and high frequency, although a definite source has not been identified. The presence of these instabilities has necessitated operating at unusually high chromaticity for much of the light source's operations. More recently transverse feedback has been able to control the instabilities and recent developments in diagnostics have allowed some investigation of the frequency and mode response of these resonances. The results of this investigation will be presented in this paper.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR023

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOR031

Trapped Ion Effects and Mitigation During High Current Operation in the Cornell DC Photoinjector

ion, radiation, experiment, linac

1735

S.J. Full, A.C. Bartnik, I.V. Bazarov, J. Dobbins, B.M. Dunham, G.H. Hoffstaetter
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: U.S. Department of Energy (Grant No. DE-SC0012493), National Science Foundation (Award No. NSF-DMR 0807731)
The Cornell high intensity photoinjector reaches a new regime of linac beam parameters where high continuous-wave electron beam currents lead to ion trapping. Above 10 mA, we have observed beam trips that limit stable machine operation to approximately 10^-15 minutes. By applying known ion clearing methods, the machine lifetime increases to at least 24 hours of continuous operation, suggesting that trapped ions are the most likely cause of the trips. In this paper we share some of our observations ion trapping in the photoinjector, as well as experimental tests of three common ion mitigation methods: clearing electrodes, beam shaking and bunch gaps.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR031

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOW003

High Average RF Power Tests With 2 RF Vacuum Windows at PITZ

gun, operation, Windows, emittance

1744

Y. Renier, G. Asova, M. A. Bakr, P. Boonpornprasert, J.D. Good, M. Groß, C. Hernandez-Garcia, H. Huck, I.I. Isaev, D.K. Kalantaryan, M. Krasilnikov, O. Lishilin, G. Loisch, D. Malyutin, D. Melkumyan, A. Oppelt, M. Otevřel, G. Pathak, T. Rublack, I.V. Rybakov, F. Stephan, G. Vashchenko, Q.T. Zhao
DESY Zeuthen, Zeuthen, Germany
M. Bousonville, S. Choroba, S. Lederer
DESY, Hamburg, Germany

The Photo Injector Test facility at DESY, Zeuthen site (PITZ), was built with the aim to develop and characterize electron sources for future usage at FLASH and at the European XFEL. Recently, the main focus at PITZ has been the study of gun reliability and photoinjector performance at high average power. The goal is to get stable and reliable operation with 6.4 MW peak power in the gun at 650 us RF pulse length and 10 Hz repetition rate. To achieve this, a new RF feed system with two RF windows was installed at PITZ in 2014. During this test, the old gun 4.2 with a modified back-plane design for better cathode contact has been used. In this contribution the results of the RF conditioning of gun 4.2 with a detailed interlock analysis will be reported as well as results from recent electron beam characterization.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW003

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOW004

Status of the STAR Project

laser, electron, focusing, controls

1747

A. Bacci, I. Drebot, L. Serafini, V. Torri
Istituto Nazionale di Fisica Nucleare, Milano, Italy
R.G. Agostino, R. Barberis, M. Ghedini, F. Martire, C. Pace
UNICAL, Arcavacata di Rende, Italy
D. Alesini, M. Bellaveglia, J.J. Beltrano, F.G. Bisesto, G. Borgese, B. Buonomo, G. Di Pirro, G. Di Raddo, A. Esposito, A. Gallo, A. Ghigo, F. Iungo, L. Pellegrino, A. Stella, C. Vaccarezza
INFN/LNF, Frascati (Roma), Italy
A. Cianchi
INFN-Roma II, Roma, Italy
G. D'Auria, A. Fabris, M. Marazzi
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
V. Petrillo
Universita' degli Studi di Milano, Milano, Italy
E. Puppin
Politecnico/Milano, Milano, Italy
M. Rossetti Conti
Universita' degli Studi di Milano & INFN, Milano, Italy

This paper reports on the final design and the work in progress on the STAR project (IPAC2014:WEPRO115), which is under construction at the Univ. of Calabria (Italy). The project is devoted to the construction of an advanced Thomson source of monochromatic tunable, ps-long, polarized X-ray beams, ranging from 40 up to 140 KeV . At present the buildings and main plants have been completed as the acquisition of main components: the RF photo-injector, the accelerating section, laser systems for collision and photo-cathode, RF Power Source and magnets are ready to start installation and site acceptance tests. The design of laser lines is complete and simulated by ZEMAX, aiming to minimize energy losses, optical distortions and providing a tunable experimental setup as well. The RF power network is close to be tested, it's based on a 55MW (2.5us pulse) S-band Klystron driven by a 500kV Pulse Forming Network based modulator and a Low Level RF system, running at 100 Hz. The Control System is been designed using EPICS and allows to manage easily and fastly each machine parameter. We expect to start commissioning the machine by the end of 2016 and obtain the first collisions within the first part of 2017.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW004

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOW034

Status Report of the Berlin Energy Recovery Linac Project BERLinPro

gun, SRF, cavity, linac

1827

M. Abo-Bakr, W. Anders, K.B. Bürkmann-Gehrlein, A.B. Büchel, P. Echevarria, A. Frahm, H.-W. Glock, F. Glöckner, F. Göbel, B.D.S. Hall, S. Heling, H.-G. Hoberg, A. Jankowiak, C. Kalus, T. Kamps, G. Klemz, J. Knobloch, J. Kolbe, G. Kourkafas, J. Kühn, B.C. Kuske, P. Kuske, J. Kuszynski, D. Malyutin, A.N. Matveenko, M. McAteer, A. Meseck, C.J. Metzger-Kraus, R. Müller, A. Neumann, N. Ohm, K. Ott, E. Panofski, F. Pflocksch, J. Rahn, J. Rudolph, M. Schmeißer, O. Schüler, M. Schuster, J. Ullrich, A. Ushakov, J. Völker
HZB, Berlin, Germany

Funding: Work supported by the German Bundesministerium für Bildung und Forschung, Land Berlin and grants of Helmholtz Association
The Helmholtz Zentrum Berlin is constructing the Energy Recovery Linac Prototype BERLinPro at the Berlin Adlershof site. The project is intended to expand the required accelerator physics and technology knowledge mandatory for the design, construction and operation of future synchrotron light sources. The project goal is the generation of a high current (100 mA), high brilliance (norm. emittance below 1 mm mrad) cw electron beam. We report on the project progress: since spring 2015 the building is under construction, ready for occupancy in January 2017. The planning phase for the first project stage is completed for the warm machine parts, the SRF gun and partly for the SRF booster. Most of the components have been ordered and are in fabrication with some already delivered. An update of the status of the various subprojects as well as a summary of future activities will be given. Project milestones and details of the timeline will be reviewed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW034

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOW044

Experimental Investigation of THz Smith-Purcell Radiation From Composite Corrugated Capillary

radiation, simulation, detector, electron

1861

K. Lekomtsev, A. Aryshev, M. Shevelev, N. Terunuma, J. Urakawa
KEK, Ibaraki, Japan
A. Ponomarenko, A.A. Tishchenko
MEPhI, Moscow, Russia

Funding: This work was supported by Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan.
Terahertz part of electromagnetic spectrum has a variety of potential applications ranging from fundamental to security applications. Further advances in development of a linac based, tunable, and narrow band coherent source of THz radiation are very important. Mechanisms of Cherenkov radiation and Smith-Purcell radiation (SPR) [*] may be used for generation of THz radiation via coherent emission [**, ***]. In this report we will present experimental investigations of the SPR generated from the corrugated capillary with a reflector, using the femtosecond multi-bunch electron beam of LUCX accelerator at KEK, Japan [****]. LUCX is capable to generate a train of 4 bunches each with 200 femtosecond (60 micrometer) duration and 200 micrometer transverse size. We will discuss the composite design of the capillary, measurements of the SPR angular distributions and the comparison of these measurements with PIC simulations. In addition, we will discuss SPR spectral characteristics; bunch energy modulation, introduced by the corrugated capillary; and the way in which the bunch spacing changes the spectrum and angular distributions of SPR.
*K.Lekomtsev et al., NIMB 355 (2015) 164
**A. M. Cook et al., PRL 103, (2009) 095003.
***S. E. Korbly et al., PRL 94, (2005) 054803.
****A. Aryshev, arXiv:1507.03302 [physics.acc-ph]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW044

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOY008

Design of a Radiotherapy Machine using the 6 MeV C-Band Standing-Wave Accelerator

linac, electron, radiation, controls

1921

H. Lim, D.H. Jeong, M.W. Lee, M.J. Lee, S.W. Shin, J. Yi
Dongnam Institute of Radiological and Medical Sciences, Busan, Republic of Korea

The majority of the radiotherapy are performed with linacs producing a uniformly intense electron-beam or X-ray beam of different energies. The linacs have the strong attraction of compactness, efficiency, reliability, moderate cost, and well-known technology. We developed and constructed the 6 MeV C-band linac which consists of a thermionic electron gun, a standing-wave accelerating column with the length of 450 mm, a 2.5 MW magnetron, a beam transport system, a beam collimation and monitoring system, and auxiliary systems of vacuum system, water cooling system etc. For the medical application, the gantry system is required to be rotated around the patient and to deliver the beam to the tumor from the linac. We design the gantry mounting our developed C-band linac isocentrically. In addition, the beam bending system and beam collimation are discussed to optimize the gantry space and to improve the beam performance. In this paper, we describe the designed radiotherapy machine including the gantry, a treatment couch and a control console, and present the study results.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOY008

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOY033

Design, Simulation and Comparison of Electrostatic Accelerating Tubes for a 1MeV Parallel Feed Cockcroft-Walton Industrial Accelerator

gun, electron, simulation, industrial-accelerators

1979

M. Nazari, F. Abbasi
Shahid Beheshti University, Tehran, Iran
F. Ghasemi
NSTRI, Tehran, Iran
M. Jafarzadeh
ILSF, Tehran, Iran

In this article accelerating tubes whit different geometries and different constructions are designed and simulated for a 1 MeV parallel feed Cockcroft-Walton electrostatic industrial accelerator. Simulations are carried out using CST Particle Studio. The accelerating tubes with different focusing electrode and accelerating electrode geometries are designed and simulated and compared with each other. Finally whit respect to the comparisons best geometry is selected. In this tube a 1 MV DC voltage is applied at several stages during the accelerating electrodes. Maximum electron beam current in the tube is 200 mA. In this application accelerating electrodes and focusing electrodes are made of stainless steel and insulators between electrodes are made of Borosilicate glass.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOY033

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOY041

A Metal-Dielectric Micro-Linac for Radiography Source Replacement

focusing, linac, electron, coupling

1992

A.V. Smirnov, S. Boucher, S.V. Kutsaev
RadiaBeam Systems, Santa Monica, California, USA
R.B. Agustsson, R.D.B. Berry, J.J. Hartzell, J. McNevin, A.Y. Murokh
RadiaBeam, Santa Monica, California, USA
G. Leyh
LOD, Brisbane, USA
E.A. Savin
MEPhI, Moscow, Russia

Funding: * US Department of Energy Contract # DE-SC0011370
To improve public security and prevent the diversion of radioactive material for Radiation Dispersion Devices, RadiaBeam is developing an inexpensive, portable, easy-to-manufacture linac structure to allow effective capture of a ~13 keV electron beam injected from a conventional electron gun and acceleration to a final energy of ~ 1 MeV. The bremsstrahlung X-rays produced by the electron beam on a high-Z converter at the end of the linac will match the penetration and dose rate of a typical ~100 Ci or more Ir-192 source. The tubular Disk-and-Ring structure under development consists of metal and dielectric elements that reduce or even eliminate multi-cell, multi-step brazing. This may allow significant simplification of the fabrication process to enable inexpensive mass-production required for replacement of the ~55,000 radionuclide sources in the US

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOY041

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOY053

In-Kind Contributions: A Prosperous Model of Procurement for Large-scale Science Projects

interface, controls, site, experiment

2017

R. Amirikas, P. Ghosh
FAIR, Darmstadt, Germany

The number of research infrastructures which are being built with significant amount of In-Kind Contributions (IKCs) from partners and stakeholders is on the increase. One of the main advantages of the utilization of IKCs in big science projects is to enable numerous partners with technological and scientific know-how participate directly in such projects. Thus, IKCs promote capacity building in technology and knowledge transfer of these partners. However, management and execution of IKCs are particularly challenging. The 2nd In-Kind Contributions Workshop (IKCW 2015) was organized by the Facility for Antiproton and Ion Research in Europe (FAIR) with the aim of sharing experiences on the procurement and management of large-scale international science projects through IKCs. This paper focuses on the analysis of the issues pertaining to how to best implement and execute IKCs from the initial phase of assignment until full delivery for both accelerator and experiments. Discussions held during IKCW 2015 are used to highlight these points further. The goal of this paper is to present the reader with a synopsis of the challenges and opportunities faced in procurement through IKCs.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOY053

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEXA01

The ESRF Low-emittance Upgrade

lattice, emittance, dipole, radiation

2023

P. Raimondi
ESRF, Grenoble, France

This talk focuses on novel aspects of the lattice design, describes the technical solutions that have been found for meeting the design goals (including the use of permanent magnet dipoles), outlines the main challenges that will be faced in commissioning and operating the new lattice in a very demanding parameter regime, and discusses how it is hoped to maximize eventual benefits for users while minimizing disruption during the upgrade process.

Slides WEXA01 [23.005 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEXA01

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOAB03

Photoemission Properties of LaB6 and CeB6 Under Various Temperature and Incident Photon Energy Conditions

cathode, laser, photon, electron

2088

K. Morita, T. Katsurayama, T. Kii, K. Masuda, T. Murata, K. Nagasaki, T. Nogi, H. Ohgaki, S. Suphakul, K. Torgasin, H. Yamashita, H. Zen
Kyoto University, Kyoto, Japan

Recently, thermionic cathode materials such as LaB6, Ir5Ce and dispenser cathodes have been also used as photocathode since they have low work function, reasonably high quantum efficiency, and long lifetime*,**. However, the effect of cathode temperature and laser wavelength on quantum efficiency is known only for limited conditions. Although it is expected to be able to lengthen the required wavelength of photocathode drive laser by heating cathodes, laser with photon energy under the work function has not been tested. Revealing them enables us to design the cost minimum accelerators. In this research, photoemission properties of LaB6 and CeB6 with various excitation photon energies will be investigated under various temperatures of the materials. Those materials have similar work function, but CeB6 have one order of magnitude smaller Richardson constant than LaB6***. By comparing photoemission properties of these materials, impact of Richardson constant on the photoemission properties will be investigated.
* S. Thorin et al. Proc of FEL2009, 310
** D. Satoh et al. Proc of IPAC2014, 679
*** J.M. Lafferty, J. Appl. Phys. 22, (1951), 299

Slides WEOAB03 [0.996 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEOAB03

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB005

Manufacturing of the IFMIF Series Power Couplers

operation, interface, cavity, cryomodule

2122

H. Jenhani, N. Bazin, N. Berton, G. Devanz, P. Hardy, V.M. Hennion
CEA/IRFU, Gif-sur-Yvette, France

In the framework of the International Fusion Materials Irradiation Facility (IFMIF), which consists of two high power CW accelerator drivers, each delivering a 125 mA deuteron beam at 40 MeV, a Linear IFMIF Prototype Accelerator (LIPAc) is presently under construction for the first phase of the project. Eight power couplers are needed for the cryomodule of LIPAc. After the validation of the two prototypes, the manufacturing of the Series Power Couplers was lunched. This paper will report the status of the manufacturing progress. It will also describe the acceptance tests in addition to the criteria adopted for these critical RF power units. The manufacturing imperfections and some finishing techniques used for the different parts will be also presented and discussed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB005

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB006

XFEL Couplers RF Conditioning at LAL

pick-up, electron, site, controls

2125

H. Guler, A. Gallas, W. Kaabi, D.J.M. Le Pinvidic, C. Magueur, M. Oublaid, A. Thiebault, A. Verguet
LAL, Orsay, France

The industrialization and the RF conditioning of 800 power couplers for the European XFEL have been performed by LAL-Orsay from fall 2013 to spring 2016. LAL laboratory has in charge the industrial monitoring, the quality control and the RF conditioning of the couplers fabricated by two different suppliers. It was the first experience of coupler production at such scale. The faced challenges, the different issues, and the lessons learned during the mass production will be reported. And finally the huge amount of RF conditioning data will be shown as one of key point on the conditioning process.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB006

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB008

ESS DTL Mechanical Design and Prototyping.

DTL, simulation, linac, dipole

2131

P. Mereu, M. Mezzano
INFN-Torino, Torino, Italy
D. Castronovo, R. Visintini
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
F. Grespan, A. Pisent, M. Poggi, C. R. Roncolato
INFN/LNL, Legnaro (PD), Italy

The Drift Tube Linac (DTL) of the European Spallation Source (ESS) is designed to operate at 352.2 MHz with a duty cycle of 4% (3 ms pulse length, 14 Hz repetition period) and will accelerate a proton beam of 62.5 mA pulse peak current from 3.62 to 90 MeV. In this paper the DTL mechanical design and simulations are presented, together with the results obtained from the prototypes of three drift tubes, equipped respectively with Permanent Magnet Quadrupole, Steerer and Beam Position Monitor.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB008

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB016

Vertical Test Results of Nitrogen Doped SRF Cavities at KEK

cavity, SRF, monitoring, operation

2154

K. Umemori, H. Inoue, E. Kako, T. Konomi, T. Kubo, H. Sakai, H. Shimizu, M. Yamanaka
KEK, Ibaraki, Japan
H. Hara, K. Sennyu, T. Yanagisawa
MHI-MS, Kobe, Japan

Recently Nitrogen doping(N-doping) technique was proposed and drastic improvements of Q-values were reported. Since high-Q operation of SRF cavities are very attractive for CW machine, we started investigation on performance of Nitrogen doped SRF cavities. Nitrogen doping systems were prepared on two vacuum furnaces, which have been used for annealing of SRF cavities. Two fine grain single cell cavities have been used for the study. After 800 degree, 3 hours annealing, N-doping were carried out under several Pa of Nitrogen pressure and followed by post annealing. Three kind of different conditions, pressure and duration time, were attempted. After applying EP-2, cavity performances were evaluated by vertical tests. Against our expectations, we observed lower Q-values, at every measurements, than those measured without N-doping. In this presentation, we describe details about N-doping system and parameters and results obtained by vertical tests. Some discussions are also given against our results.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB016

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB029

Research of Nitrogen Doping at IHEP

niobium, cavity, experiment, electron

2186

P. Sha
Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing, People's Republic of China
J.P. Dai
IHEP, Beijing, People's Republic of China
F. Jiao
PKU, Beijing, People's Republic of China

Funding: Work funded by National Natural Science Foundation of China, Grant No. 11505197
Recently, nitrogen doping (N-doping) technology has been proved to increase Q0 of superconducting cavity obviously, which lowers the BCS surface resistance. After N-doping, Q0 of 9-cell 1.3 GHz cavity can be increased to 3*10¹⁰ at Eacc = 16 MV/m, while 1.5*1010 without N-doping [1]. Since 2013, there have been over 60 cavities nitrogen doped at FNAL, JLAB and Cornell. The Circular Electron Collider (CEPC) has been proposed by IHEP in China, while requests Q0=4e10@Eacc=15.5 MV/m for 650 MHz cavity. It's hard to achieve without N-doping. So research of N-doping was begun in cooperation with Peking University in early 2015. Experiments of niobium samples have showed that nitrogen concentration at niobium surface increased a lot after N-doping. After then, several single-cell 1.3 GHz cavities completed vertical tests, but there're no successful test results of Q0 increasing, yet.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB029

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB041

Design of RF Power Coupler for RISP Half Wave Resonator

simulation, impedance, cavity, electron

2208

S. Lee, E.-S. Kim
Korea University Sejong Campus, Sejong, Republic of Korea
I. Shin
IBS, Daejeon, Republic of Korea

RF power couplers for half wave resonators are under development for the Rare Isotope Science Project (RISP) in Korea. It is required to deliver up to 6 kW RF power at 162.5 MHz to the HWR in CW mode. The RF coupler is a coaxial capacitive type using a disc type ceramic window. Design studies of 2nd prototype HWR RF coupler are presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB041

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB044

Development of RF Conditioning System for RISP RF Power Couplers

controls, cavity, ion, heavy-ion

2211

C.K. Sung, E.-S. Kim
Korea University Sejong Campus, Sejong, Republic of Korea
S. Lee, I. Shin
IBS, Daejeon, Republic of Korea

RF power coupler prototypes have been conditioned for a heavy ion accelerator of the Rare Isotope Science Project (RISP) in Korea. The RF couplers operate for 162.5 MHz half-wave resonators at 6 kW RF power. The RF couplers are a 50-Ohm coaxial structure with a disk type ceramic window at room temperature. The control system using Labview software supported automatic process for RF conditioning, data acquisition and interlock system. The conditioning system and the result of conditioning of RF coupler are presented in this paper.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB044

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB052

System Integration and Beam Commissioning of the 500-MHz RF Systems for Taiwan Photon Source

SRF, cavity, operation, storage-ring

2234

Ch. Wang, L.-H. Chang, M.H. Chang, C.-T. Chen, L.J. Chen, F.-T. Chung, M.-C. Lin, Z.K. Liu, C.H. Lo, G.-H. Luo, C.L. Tsai, H.H. Tsai, M.H. Tsai, M.-S. Yeh, T.-C. Yu
NSRRC, Hsinchu, Taiwan

The accelerator complex of the Taiwan Photon Source (TPS) consists of two 500-MHz RF systems: one RF system with two KEKB-type single-cell SRF modules is operated for the 3-GeV storage ring of circumference 518 m, and the other with one five-cell Petra cavity at room temperature is for the concentric full-energy booster synchrotron. This report overviews the installation, system integration, commissioning, and initial operation of the 500-MHz RF systems for the TPS with emphasis on our solution to approach the highly reliable SRF operation at its maximum design beam current of 500-mA. Lessons learned during the project are reviewed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB052

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB053

Study of Third Harmonic Cavity for Taiwan Photon Source

cavity, dipole, electron, scattering

2237

Z.K. Liu, L.-H. Chang, M.H. Chang, L.J. Chen, PY. Chen, F.-T. Chung, M.-C. Lin, C.H. Lo, C.L. Tsai, M.H. Tsai, Ch. Wang, M.-S. Yeh, T.-C. Yu
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) is a modern light source with 3 GeV electron energy and low emittance. The bunch length is about 3 mm at designed beam current of 500 mA and operating gap voltage of 3.2 MV. The short bunch length results in short Touschek lifetime and high parasitic loss of insertion device (ID). Some of the undulators are operated in vacuum at TPS, therefore the head load become an important issue. To install higher harmonic cavity is a solution for improving the Touschek lifetime and the heat load by lengthening the bunch length. The effect of installing 3rd harmonic cavity for TPS is investigated. The expected maximum elongation factor for bunch lengthening, as well as the effect on the Touschek lifetime and heat load of ID are presented in this paper.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB053

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMR004

Cryomdoule Test Stand Reduced-Magnetic Support Design at Fermilab

cryomodule, cavity, SRF, linac

2262

M.W. McGee, S.K. Chandrasekaran, A.C. Crawford, E.R. Harms, J.R. Leibfritz, G. Wu
Fermilab, Batavia, Illinois, USA

Funding: Operated by Fermi Research Alliance, LLC, under Contract No. DE-AC02- 07CH11359 with the U.S. Department of Energy
In a partnership with SLAC National Accelerator Laboratory (SLAC) and Jefferson Lab, Fermilab will assemble and test 17 of the 35 total 1.3 GHz cryomodules for the Linac Coherent Light Source II (LCLS-II) Project. These devices will be tested at Fermilab's Cryomodule Test Facility (CMTF) within the Cryomodule Test Stand (CMTS-1) cave. The problem of magnetic pollution became one of major issues during design stage of the LCLS-II cryomodule as the average quality factor of the accelerating cavities is specified to be 2.7 x 10¹⁰. One of the possible ways to mitigate the effect of stray magnetic fields and to keep it below the goal of 5 mGauss involves the application of low permeable materials. Initial permeability and magnetic measurement studies regarding the use of 316L stainless steel material indicated that cold work (machining) and heat affected zones from welding would be acceptable.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR004

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMR006

Transport of LCLS-II 1.3 GHz Cryomodule to SLAC

cryomodule, acceleration, alignment, cavity

2268

M.W. McGee, T.T. Arkan, T.J. Peterson, Z. Tang
Fermilab, Batavia, Illinois, USA
S.R. Boo, M. Carrasco
SLAC, Menlo Park, California, USA
E. Daly, N.A. Huque
JLab, Newport News, Virginia, USA

Funding: Operated by Fermi Research Alliance, LLC, under Contract No. DE-AC02- 07CH11359 with the U.S. Department of Energy.
In a partnership with SLAC National Accelerator Laboratory (SLAC) and Jefferson Lab, Fermilab will assemble and test 17 of the 35 total 1.3 GHz cryomodules for the Linac Coherent Light Source II (LCLS-II) Project. These include a prototype built and delivered by each Lab. Another two 3.9 GHz cryomodules will be built, tested and transported by Fermilab to SLAC. Each assembly will be transported over-the-road from Fermilab or Jefferson Lab using specific routes to SLAC. The transport system consists of a base frame, isolation fixture and upper protective truss. The strongback cryomodule lifting fixture is described along with other supporting equipment used for both over-the-road transport and local (on-site) transport at Fermilab. Initially, analysis of fragile components and stability studies will be performed in order to assess the risk associated with over-the-road transport of a fully assembled cryomodule.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR006

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMR013

Study of LCLS-II Fundamental Power Coupler Heating in HTS Integrated Cavity Tests

cavity, resonance, HOM, simulation

2286

N. Solyak, I.V. Gonin, A. Grassellino, C.J. Grimm, T.N. Khabiboulline, J.P. Ozelis, K. Premo, O.V. Prokofiev, D.A. Sergatskov, G. Wu
Fermilab, Batavia, Illinois, USA

LCLS-II coupler based on modified design of TTF3 coupler for higher average power was assembled on high Q cavity and tested at HTS as part of integrated cavity test program. Couplers were thermally connected to thermal shields and equipped with diagnostics to control temperature in different locations and provide information about cryogenic heat loads at 2 K, 5 K and 80 K.Three dressed cavities with power couplers were tested in HTS at full specified RF power. Results are summarized in this paper and cross-checked with simulation.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR013

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMR020

First Cool-down of the Cornell ERL Main Linac Cryo-Module

cavity, linac, cryomodule, HOM

2305

R.G. Eichhorn, J.V. Conway, F. Furuta, G.M. Ge, D. Gonnella, T. Gruber, G.H. Hoffstaetter, J.J. Kaufman, M. Liepe, T.I. O'Connell, P. Quigley, D.M. Sabol, J. Sears, E.N. Smith, V. Veshcherevich
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Cornell University has finished building a 10 m long superconducting accelerator module as a prototype of the main linac of a proposed ERL facility. This module houses 6 superconducting cavities- operated at 1.8 K in continuous wave (CW) mode with a design field of 16 MV/m and a Quality factor of 2x10¹⁰. We wil shortly review the design and focus on reporting on the first cool-down of this module. We will giving data for various cool-down scenarios (fast/ slow), uniformity and performance

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR020

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMR026

RF Losses from Trapped Flux in SRF Cavities

cavity, SRF, site, niobium

2327

D. Gonnella, J.J. Kaufman, P.N. Koufalis, M. Liepe
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: NSF
Previous measurements at Cornell have shown that the sensitivity of residual resistance to trapped magnetic field in SRF cavities is heavily dependent on the mean free path of the RF penetration layer of the niobium. Here we report on a systematic study of ten cavity preparations with different mean free paths and the effect of these preparations on sensitivity to trapped magnetic flux. In the clean limit, longer mean free path leads to a lower sensitivity to trapped magnetic flux while in the dirty limit the opposite is true, shorter mean free path leads to lower sensitivity. These results are also shown to be in good agreement with theoretical predictions of RF losses due to oscillations of vortex lines.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR026

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMR029

New Material Studies in the Cornell Sample Host Cavity

cavity, niobium, SRF, superconducting-RF

2338

J.T. Maniscalco, D.L. Hall, M. Liepe
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
O.B. Malyshev, R. Valizadeh, S. Wilde
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
S. Wilde
Loughborough University, Loughborough, Leicestershire, United Kingdom

Cornell has developed a TE mode sample host microwave cavity in order to study large, flat samples of novel SRF materials. In recent calibration tests, the cavity was shown to reach peak magnetic fields on the sample plate of >100 mT and a quality factor Q₀ greater than 10¹⁰, making it a powerful system to study the performance of superconductors at high RF fields with nOhms sensitivity. In this report we present results of measurements of two samples of thin-film Nb deposited on Cu using HiPIMS at 500 C and at 800 C.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR029

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMR033

Observation of Stable Low Surface Resistance in Large-Grain Niobium SRF Cavities

cavity, niobium, SRF, site

2344

R.L. Geng
JLab, Newport News, Virginia, USA
S.C. Huang
IMP/CAS, Lanzhou, People's Republic of China

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Low surface resistance, or high unloaded quality factor (Q0), superconducting radio frequency (SRF) cavities are being pursued actively nowadays as their application in large-scale CW SRF accelerators can save capital and operational cost in cryogenics. There are different options in realization of such cavities. One of them is the large-grain (LG) niobium cavity. In this contribution, we present new experimental results in evaluation of LG niobium cavities cooled down in the presence of an external magnetic field. High Q0 values are achieved even with an ambient magnetic field of up to 100 mG. More over, it is observed that these high Q0 values are super-robust against repeated quench, literally not affected at all after the cavity being deliberately quenched for hundreds of times in the presence of an ambient magnetic field of up to 200 mG.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR033

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMR045

Engineering Issues of the Medium Energy Beam Transport Line and SRF Linac for the LIPAc

linac, SRF, alignment, solenoid

2377

D. Gex, H. Dzitko, A. Lo Bue, G. Phillips, L. Semeraro, J.M. Zarzalejos
F4E, Germany
N. Bazin, G. Devanz, P. Hardy
CEA/IRFU, Gif-sur-Yvette, France
J. Castellanos, J.M. García, D. Jiménez-Rey, D. López, L.M. Martínez, I. Podadera
CIEMAT, Madrid, Spain
O. Nomen
IREC, Sant Adria del Besos, Spain
F. Scantamburlo
IFMIF/EVEDA, Rokkasho, Japan

The International Fusion Materials Irradiation Facility (IFMIF) aims to provide an accelerator-based, D-Li neutron source to produce high energy neutrons at sufficient intensity and irradiation volume for DEMO materials qualification. Part of the Broader Approach (BA) agreement between Japan and EURATOM, the goal of the IFMIF/EVEDA project is to work on the engineering design of IFMIF and to validate the main technological challenges which, among a wide diversity of hardware includes the LIPAC (Linear IFMIF Prototype Accelerator), a 125 mA CW deuteron accelerator up to 9 MeV mainly designed and manufactured in Europe. The aim of this paper is to address the engineering issues of the MEBT and SRF linac related to assembly and Integration at LIPAc facility, focusing in the seismic analysis of the beamlines to ensure the robustness of the equipment and the alignment activities with the cutting edge technology performed in Europe before sending the components to Rokkasho. These activities are essential before starting the installation process of the MEBT in the first half of 2016, and to initiate the assembly and integration of the SRF Linac cryomodule in the next phase.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR045

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMR048

Hall Element Relative Position and Angle Calibrations for the Cryogenic Permanent Magnet Undulator

undulator, cryogenics, permanent-magnet, dipole

2386

L. Gong, W. Chen, W. Kang, L.Z. Li, H.H. Lu, Y.F. Yang
IHEP, Beijing, People's Republic of China

A three dimensions Hall probe will be manufactured for characterizing the magnetic performance of Cryogenic Permanent Magnet Undulator (CPMU) of Chinese High Energy Photon Source and the test facility (HEPS-TF) at Institute of High Energy Physics (IHEP). The positional and angular misalignment errors of the Hall sensors play an important role in the measurement accuracy of CPMU. In order to minimize the misalignment errors, a method of calibrating relative displacements and assembly angles of a 3-D Hall probe is carried out. In this paper, details of the calibration procedures and the data processing are presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR048

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMW004

Progress in Detector Design and Installation for Measurements of Electron Cloud Trapping in Quadrupole Magnetic Fields at CesrTA

electron, quadrupole, detector, positron

2420

J.A. Crittenden, S. Barrett, M.G. Billing, K.A. Jones, Y. Li, T.I. O'Connell, K. Olear, S. Poprocki, D. L. Rubin, J.P. Sikora
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work supported by the US National Science Foundation PHY-1416318, PHY-0734867, PHY-1002467, and the U.S. Department of Energy DE-FC02-08ER41538
Following up on our 2013 and 2014 measurements of electron cloud trapping in a quadrupole magnet with 7.4~T/m gradient in the 5.3~GeV positron storage ring at Cornell University, we have redesigned the shielded-stripline time-resolving electron detector and installed a wide-aperture quadrupole magnet at a location in the ring where its field can be compensated by a nearby quadrupole, thus allowing the first measurements of cloud trapping as a function of field gradient. The transverse acceptance of the electron detector has been tripled, allowing tests of model predictions indicating a dramatic cloud splitting effect which exhibits a threshold behavior as a function of bunch population. In addition, a vacuum chamber optimized for cloud buildup measurements using resonant microwave phenomena has been employed. We describe design considerations and modeling predictions for the upcoming 2016 data-taking run. This project is part of the CESR Test Accelerator program, which investigates performance limitations in low-emittance storage and damping rings.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW004

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMY020

Integration of a Terawatt Laser at the CERN SPS Beam for the AWAKE Experiment on Proton-Driven Plasma Wake Acceleration

laser, plasma, proton, electron

2592

V. Fedosseev, M. Battistin, E. Chevallay, N. Chritin, V. Clerc, T. Feniet, F. Friebel, F. Galleazzi, P. Gander, E. Gschwendtner, J. Hansen, C. Heßler, M. Martyanov, A. Masi, A. Pardons, F. Salveter, K.A. Szczurek
CERN, Geneva, Switzerland
M. Martyanov, J.T. Moody, P. Muggli
MPI-P, München, Germany

In the AWAKE experiment a high-power laser pulse ionizes rubidium atoms inside a 10 m long vapor cell thus creating a plasma for proton-driven wakefield acceleration of electrons. Propagating co-axial with the SPS proton beam the laser pulse seeds the self-modulation instability within the proton bunch on the front of plasma creation. The same laser will also generate UV-pulses for production of a witness electron beam using an RF-photoinjector. The experimental area formerly occupied by CNGS facility is being modified to accommodate the AWAKE experiment. A completely new laser laboratory was built, taking into account specific considerations related to underground work. The requirements for AWAKE laser installation have been fulfilled and vacuum beam lines for delivery of laser beams to the plasma cell and RF-photoinjector have been constructed. First results of laser beam hardware commissioning tests following the laser installation will be presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMY020

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMY026

A Gas-filled Capillary Based Plasma Source for Wakefield Experiments

plasma, high-voltage, experiment, simulation

2613

O. Mete Apsimon, K. Hanahoe, T.H. Pacey, G.X. Xia
UMAN, Manchester, United Kingdom

Funding: This work is supported by the University of Manchester Strategic Grant.
A plasma medium can be formed when a gas is discharged via an applied high voltage within a capillary tube. A high voltage discharge based plasma source for plasma wake- field acceleration experiment is being developed. Design considered a glass capillary tube with various inner radii. Glass was preferred to sapphire or quartz options to ease the machining. Electrodes will be attached to the tube using a sealant resistant to high vacuum conditions and baking at high temperatures. Each electrode will be isolated from the neighbouring one using nuts or washers from a thermoplastic polymer insulator material to prevent unwanted sparking outside of the tube. In this paper, general design considerations and possible working points of this plasma source are presented for a range of plasma densities from 1×10²⁰ to 1×10²² m^−3. Consideration was also given to plasma density diagnostic techniques due to critical dependence of accelerating gradient on plasma density.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMY026

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMY035

Preliminary Commissioning Results of the Proton Source for ESS at INFN-LNS

plasma, proton, diagnostics, electron

2628

L. Celona, L. Allegra, A. Amato, G. Calabrese, A.C. Caruso, G. Castro, F. Chines, G. Gallo, S. Gammino, O. Leonardi, A. Longhitano, G. Manno, S. Marletta, D. Mascali, A. Maugeri, M. Mazzaglia, L. Neri, S. Passarello, G. Pastore, A. Seminara, A.S. Spartà, G. Torrisi, S. Vinciguerra
INFN/LNS, Catania, Italy
S. Di Martino, P. Nicotra
Si.A.Tel SRL, Catania, Italy
A. Longhitano
ALTEK, San Gregorio (CATANIA), Italy
G. Torrisi
Universitá Mediterranea di Reggio Calabria, Reggio Calabria, Italy

At Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS) - the commissioning of the high intensity Proton Source for the European Spallation Source (PS-ESS) is under way. Preliminary results of plasma diagnostics collected on a testbench called "Flexible Plasma Trap" (FPT) will be correlated to the peculiarities of the magnetic system design and of the microwave injection setup with a view of the possible implications on the beam extraction system. The status of the costruction is presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMY035

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOR017

A Micrometric Positioning Sensor for Laser-Based Alignment

laser, experiment, alignment, target

2700

G. Stern, H. Mainaud Durand, D. Piedigrossi, M. Sosin
CERN, Geneva, Switzerland
A. Geiger, S. Guillaume
ETH, Zurich, Switzerland

The Compact Linear Collider requires 10 μm accuracy over 200m for the alignment of its components. Since current techniques based on stretched wire or water level are difficult to implement, other options are under study. We propose a laser alignment system using positioning sensors made of camera/shutter assemblies. The goal is to implement such a positioning sensor. The corresponding studies comprise design and calibration as well as investigations of measurement accuracy and precision. On the one hand, we describe mathematically the laser beam propagation, its interaction with the shutter and image processing. On the other hand, we present experiments done with the prototype of a positioning sensor. As a result, we give practical suggestions to build the positioning sensors and we describe a calibration protocol to be applied to all sensors before measuring. In addition, we deliver estimates for measurement accuracy and precision. Our work provides the first steps towards a full alignment system.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR017

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOR018

Position Monitoring System for HL-LHC Crab Cavities

cavity, monitoring, radiation, alignment

2704

M. Sosin, T. Dijoud, H. Mainaud Durand
CERN, Geneva, Switzerland
V. Rude
ESGT-CNAM, Le Mans, France

The high luminosity upgrade for the LHC at CERN (HL-LHC project) will extend the discovery potential of the LHC by a factor 10. It relies on key innovative technologies like superconducting cavities for beam rotation, named 'crab cavities'. Two crab cavities will be hosted in a superconducting cryostat working at a cold (<3 K). The position of each cavity will be monitored during the cool-down and the operation in order to comply with the tight alignment tolerances: the misalignment of a cavity axis w.r.t. the other will have to be lower than 0.5 mm and each cavity roll w.r.t. the cryostat axis will have to be lower than 1 mrad. Moreover, the monitoring system will have to be radiation hard (up to 10 MGy) and maintenance free. We propose a solution based on the Frequency Scanning Interferometry to provide the position monitoring of the crab cavities. This paper describes the design and study of such a solution, including the engineering approach, the issues encountered and the lessons learnt.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR018

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOR059

Calculation for the Radiation Dose in Storage Ring Hall based on Monte Carlo Method

radiation, storage-ring, electron, neutron

2805

S. Huang, T.L. He, S.C. Zhang, T. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Radiation dose assessment in synchrotron radiation facility is challenging due to the complexity and uncertainties of radiation source terms induced by high energy particle accelerator. Hefei light source (HLS) is the first dedicated synchrotron radiation light source in China. Radiation dose assessment for users at HLS Beam lines is highly concerned. This study presents the method calculating the radiation dose in storage ring hall under normal operation state, the simplified Monte Carlo calculation model was introduced in detail. We obtained the results of radiation dose distribution in HLS storage ring hall with using MCNP, which are in the same order of magnitude with the experimental results. It indicates that the method can be used to calculate the radiation dose level in storage ring hall, and it has certain guiding significance for the radiation protection.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR059

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW001

Sirius Status Report

storage-ring, booster, dipole, kicker

2811

A.R.D. Rodrigues, F.C. Arroyo, O.R. Bagnato, J.F. Citadini, R.H.A. Farias, J.G.R.S. Franco, L. Liu, S.R. Marques, R.T. Neuenschwander, C. Rodrigues, F. Rodrigues, R.M. Seraphim, O.H.V. Silva
LNLS, Campinas, Brazil

Sirius is a Synchrotron Light Source Facility based on a 4th generation low emittance storage ring that is presently under construction in Campinas, Brazil. During the last year, accelerator activities concentrated on R&D of the various subsystem components. However, the number of components under production or already delivered is also increasing according to planning. The building construction started in the beginning of 2015 and machine commissioning is expected to start mid 2018. In this paper we report on the present status of the project with emphasis on the last year activities.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW001

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW016

Designing an Ultra Low Emittance Lattices for Iranian Light Source Facility Storage Ring

emittance, lattice, storage-ring, scattering

2858

E. Ahmadi, M. Jafarzadeh, J. Rahighi
ILSF, Tehran, Iran
H. Ghasem
IPM, Tehran, Iran
S.M. Jazayeri
IUST, Narmac, Tehran, Iran

Electron storage rings are extensively used for high luminosity colliders, damping rings in high-energy physics and synchrotron light sources. To further increase the luminosity at the colliders or brightness of a synchrotron light sources, the beam emittance is being continually pushed downward. In this paper, we investigate the lattice design for the storage ring of Iranian Light Source Facility (ILSF) with an ultra-low emittance, intermediate energy of 3 GeV and circumference of 528 m. We present the design results for a five-band achromat lattice with the natural emittance of 276 pm-rad. The base line is based on 20 straight sections with the length of 7 m.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW016

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW029

Solaris Storage Ring Commissioning

storage-ring, radiation, optics, closed-orbit

2895

A.I. Wawrzyniak, P.B. Borowiec, L.J. Dudek, K. Karaś, A.M. Marendziak, K. Wawrzyniak, J. Wikłacz, M. Zając
Solaris National Synchrotron Radiation Centre, Jagiellonian University, Kraków, Poland
C.J. Bocchetta, M. Boruchowski, P. Bulira, P.P. Goryl, A. Kisiel, W.T. Kitka, M.P. Kopec, P. Król, M.J. Stankiewicz, J.J. Wiechecki, L. Żytniak
Solaris, Kraków, Poland
R. Nietubyć
NCBJ, Świerk/Otwock, Poland

Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09
The Solaris storage ring represents a new class of light source that utilizes the innovative concept of a solid iron block containing all the Double Bend Achromat (DBA) magnets. The use of small magnet gaps brings the benefit of high fields but requires vacuum chambers of high me-chanical accuracy and distributed pumping. Due to very tight mechanical tolerances of the magnet blocks and of the vacuum vessels, the installation of the Solaris storage ring was a challenging task. In this paper the commission-ing results and the performance of this novel machine will be discussed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW029

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW031

Performance of the Vacuum System for the Solaris 1.5 GeV Electron Storage Ring

storage-ring, injection, electron, synchrotron

2898

A.M. Marendziak, C.J. Bocchetta, P.B. Borowiec, P. Bulira, L.J. Dudek, P.P. Goryl, K. Karaś, A. Kisiel, W.T. Kitka, M.P. Kopec, M. Madura, R. Nietubyć, M.P. Nowak, M.J. Stankiewicz, A.I. Wawrzyniak, K. Wawrzyniak, J.J. Wiechecki, J. Wikłacz, M. Zając, Z. Zbylut, L. Żytniak
Solaris National Synchrotron Radiation Centre, Jagiellonian University, Kraków, Poland

Solaris is a third generation light source recently constructed at the Jagiellonian University in Kraków, Poland. The machine was designed by the team at the MAX IV Laboratory. A replica of the 1.5 GeV MAX IV storage ring with a 96 m circumference was successfully built at Solaris and now the facility is in its 3rd phase of commissioning. The average pressure in the storage ring was 1.2·10^-10 mbar before beam commissioning and increases to 1.2·10-8 mbar with 511 mA of stored beam current for electron energy of 524 MeV. With 10 A·h accumulated beam dose, beam cleaning has permitted an average pressure of 3·10-10 mbar/mA. In this paper the result of vacuum performance from beam cleaning and the beam lifetime will be presented. Moreover vacuum maintenance procedures will be reported.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW031

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW032

Impact of the DBA Blocks Alignment on the Beam Dynamics of the Storage Ring in Solaris

storage-ring, alignment, electron, synchrotron

2902

J.J. Wiechecki, C.J. Bocchetta, M. Boruchowski, P. Król, A.I. Wawrzyniak
Solaris, Kraków, Poland
K. Karaś, A.M. Marendziak, R. Nietubyć
Solaris National Synchrotron Radiation Centre, Jagiellonian University, Kraków, Poland

Installation of the Solaris synchrotron has been accomplished at the beginning of the 2015. Although the machine is a replica of the 1.5 GeV ring at MAX IV in Sweden, the entire group responsible for the installation, was facing numerous problems during the entire installation period. One of the most critical issues that are responsible for the proper functionality of the machine is the survey of the machine. An appropriate alignment of the components in accordance to each other as also to the building, provides a good quality of the beam so extensively desired by the beamline's users. This paper presents the results of the alignment in the 1.5 GeV ring, describes possible critical sectors of the ring that might influence the accuracy of the measurements and juxtapose the results with the values gained during the operational phase of the synchrotron. This comparison enables the identification of the beam losses and extension of the lifetime of the electron beam.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW032

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW040

Preliminary Beam Test for TPS Fast Orbit Feedback System

feedback, power-supply, interface, electronics

2930

P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Huang, C.Y. Liao
NSRRC, Hsinchu, Taiwan

TPS (Taiwan Photon Source) is a 3 GeV synchrotron light source which had be successfully commissioning with SRF up to 500 Amp in 2015 and scheduled to open user operation in 2016. As most of the 3rd generation light source, the fast orbit feedback system would be adopted to eliminate various disturbances and improve orbit stability. Due to the vacuum chamber material made of aluminum with higher conductivity and lower bandwidth, extra fast correctors mounted on bellows will be used for FOFB correction loop and DC correction of fast correctors would be transferred to slow ones and avoid fast corrector saturation. This report summarizes the infrastructure of the FOFB and the preliminary beam test is also presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW040

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW046

Status of the Front Ends Project at MAXIV

storage-ring, radiation, insertion, insertion-device

2947

A. Bartalesi, Y. Cerenius
MAX IV Laboratory, Lund University, Lund, Sweden
S. Forcat Oller
SLAC, Menlo Park, California, USA

The MAX IV laboratory is a Swedish national laboratory for synchrotron radiation hosted by the Lund University. It will operate two storage rings to produce synchrotron light of very high intensity and quality over a broad wavelength range. A linear accelerator will feed these storage rings in topping up mode as well as serve as an electron source for a short pulse facility built on its extension. The storage rings have different sizes and operates at different energies: the MAX IV 1.5 GeV ring has 12 straight sections optimized for soft x-rays; while the MAX IV 3.0 GeV ring, has 20 straight sections, optimized for harder x-rays. In the initial stage of the project, five beamlines are foreseen to operate on the 3 GeV storage ring and an additional five on the 1.5 GeV ring. Each beamline requires a front end to interface the different characteristics in terms of vacuum level, heat loads, radiation safety, beam size and position, with respect to the storage ring. This paper describes the status of the different Front Ends project at MAXIV.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW046

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW047

A Hybrid Superconducting/Normal Conducting RF System for the Diamond Light Source Storage Ring

cavity, operation, storage-ring, HOM

2950

C. Christou, A.G. Day, P. Gu, N.P. Hammond, J. Kay, M. Maddock, P.J. Marten, S.A. Pande, A.F. Rankin, D. Spink
DLS, Oxfordshire, United Kingdom

300 mA beam in the Diamond Light Source storage ring is presently maintained by two 500 MHz superconducting CESR-B cavities. Cavity reliability is acceptable at modest operating voltages up to 1.4 MV per cavity but falls off rapidly beyond this value. The installation of an extra cavity or cavities would reduce the voltage demand on the current superconducting cavities and also the operating power level of the high power amplifiers, with commensurate improvement in machine reliability. Furthermore, two superconducting cavity failures in recent years have resulted in machine down-time and reduced-current operation and repair has proven to be prolonged and expensive. It is therefore planned to install two normal conducting cavities into the ring to support operation of the superconducting cavities and to act as a safeguard against any future superconducting cavity failures. Details are presented in this paper of plans and progress towards the installation of the hybrid RF system.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW047

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW048

Preparations for the Double Double Bend Achromat Installation in Diamond Light Source

dipole, sextupole, feedback, quadrupole

2953

R.P. Walker, C.A. Abraham, C.P. Bailey, R. Bartolini, P. Coll, M.P. Cox, N.P. Hammond, M.T. Heron, S.E. Hughes, J. Kay, I.P.S. Martin, S.P. Mhaskar, A.G. Miller, A.J. Reed, G. Rehm, E.C.M. Rial, A.J. Rose, A. Shahveh, H.S. Shiers, A. Thomson
DLS, Oxfordshire, United Kingdom
R. Bartolini
JAI, Oxford, United Kingdom

We present the status of preparations for a major installation in the Diamond storage ring which is due to take place in 2016, namely the conversion of one cell of the ring from a double bend achromat (DBA) structure, to a double-DBA, or DDBA. We present results of measurements of the new narrow bore, high strength, quadrupoles and sextupoles, as well as the four new gradient dipoles. Fabrication of entirely new narrow-gap vacuum vessel strings, a mixture of copper and stainless steel is also described. The status of assembly of the two 7m long girders is presented, as well as other preparatory engineering, power supply, controls and high level software work.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW048

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW051

R+D Progress Towards a Diffraction Limited Upgrade of the ALS

injection, undulator, emittance, storage-ring

2962

C. Steier, A. Anders, J.M. Byrd, K. Chow, S. De Santis, R.M. Duarte, J.-Y. Jung, T.H. Luo, H. Nishimura, T. Oliver, J.R. Osborn, H.A. Padmore, G.C. Pappas, D. Robin, F. Sannibale, D. Schlueter, C. Sun, C.A. Swenson, M. Venturini, W.L. Waldron, E.J. Wallén, W. Wan, Y. Yang
LBNL, Berkeley, California, USA

Funding: This work was supported by the Laboratory Directed Research and Development Program of Lawrence Berkeley National Laboratory under U.S. Department of Energy Contract No. DE-AC02-05CH11231.
Improvements in brightness and coherent flux of about two orders of magnitude over operational storage ring based light sources are possible using multi bend achromat lattice designs. These improvements can be implemented as upgrades of existing facilities, like the proposed upgrade of the Advanced Light Source, making use of the existing infrastructure, thereby reducing cost and time needed to reach full scientific productivity on a large number of beamlines. An R&D program was started at LBNL to further develop the technologies necessary for diffraction-limited storage rings. It involves many areas, and focuses on the specific needs of soft x-ray facilities: NEG coating of small chambers, swap-out injection, bunch lengthening, magnets/radiation production, x-ray optics, and beam physics design optimization. Hardware prototypes have been built and concepts and equipment was tested in beam tests on the existing ALS.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW051

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOY048

Overview of the Design of the IBEX Linear Paul Trap

ion, experiment, alignment, multipole

3104

S.L. Sheehy
JAI, Oxford, United Kingdom
D.J. Kelliher, S. Machida, D.C. Plostinar, C.R. Prior
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom

We report on the status and design of the Intense Beam Experiment (IBEX) at RAL. This experiment consists of a linear Paul trap apparatus similar to the S-POD system at University of Hiroshima, confining non-neutral Argon plasma in an RF quadrupole field. The physical equivalence between this device and a beam in a linear focusing channel makes it a useful tool for accelerator physics studies including resonances and high intensity effects. We give an overview of the design and construction of IBEX and outline plans for commissioning and the future experimental programme.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOY048

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOY055

NSLS-II Accelerator Commissioning and Transition to Operations

operation, lattice, storage-ring, injection

3120

T.V. Shaftan
BNL, Upton, Long Island, New York, USA

Over past year NSLS-II has completed accelerator commissioning and enabled operations of first project beam lines. Recently we further optimized the NSLS-II accelerators, increased the beam current to 400 mA without- and to 250 mA with Insertion Devices (IDs), commissioned top-off mode of operations and stabilized beam orbit to below 10% of the beam size in the source points. In this paper we report progress on the NSLS-II accelerator commissioning and operations and plans for future facility developments.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOY055

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THYB01

Performance of Superconducting Cavities for the European XFEL

cryomodule, cavity, operation, SRF

3186

D. Reschke
DESY, Hamburg, Germany

The superconducting accelerator of the European XFEL consists of the injector part and the main linac. The injector includes one 1.3 GHz accelerator module and one 3.9 GHz third harmonic module, while the main linac consists of 100 accelerator modules, each housing eight 1.3 GHz TESLA-type cavities, operated at an average design gradient of 23.6 MV/m. The fabrication and surface treatment by industry as well as the vertical and cryomodule RF tests of the required 808 superconducting 1.3GHz cavities are analysed and presented.

Slides THYB01 [3.227 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THYB01

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THOBB01

PAL-XFEL Linac RF System

klystron, linac, network, radiation

3192

H.-S. Lee, H. Heo, J. Hu, H.-S. Kang, K.W. Kim, K.H. Kim, S.H. Kim, I.S. Ko, S.S. Park, Y.J. Park
PAL, Pohang, Kyungbuk, Republic of Korea
H. Matsumoto
KEK, Tokai, Ibaraki, Japan

The PAL-XFEL hard X-ray linac has a 716 m long gallery and tunnel for 10 GeV. Forty nine modulators are necessary in the hard X-ray gallery for an X-band linearizer, an S-band RF gun, two S-band deflectors and 45 S-band klystrons for accelerating structures. They have been installed completely from March 15, 2015 to December 30, 2015 after completing the building construction. There are 51 modulators, 178 accelerators structures, 42 SLEDs in the hard X-ray linac and the soft X-ray linac. The RF conditioning of the klystrons, SLEDs and accelerating structures were stated from November 24, 2015. We describe the PAL-XFEL system and the current status of the linac RF system.

Slides THOBB01 [22.023 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THOBB01

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THOBB02

Impurity Doping of Superconducting Radio Frequency Cavities

cavity, niobium, SRF, radio-frequency

3195

P.N. Koufalis, F. Furuta, G.M. Ge, D. Gonnella, J.J. Kaufman, M. Liepe, J.T. Maniscalco
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: NSF PHYS-1416318
Impurity doping of bulk-niobium superconducting radio frequency (SRF) cavities is a relatively new field of study and the underlying physics is not yet fully understood. Previous studies have shown an increase in the intrinsic quality factor and the corresponding decrease of the temperature-dependent component of the surface resistance of nitrogen-doped cavities with increasing accelerating field.* Here we investigate the effects of alternative inert dopants on the surface resistance and thus the intrinsic quality factor of SRF cavities in pursuit of the optimal dopant and doping level.
A. Grassellino et al., Nitrogen and Argon Doping of Niobium for Superconducting Radio Frequency Cavities. Supercond. Sci. Technol., 26(102001), 2013

Slides THOBB02 [4.048 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THOBB02

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THOBB03

Root Causes of Field Emitters in SRF Cavities Placed in CEBAF Tunnel

cavity, cryomodule, SRF, operation

3198

R.L. Geng
JLab, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
It has been suspected that appearance of new field emitters can occur in SRF cavities after their placement in accelerator tunnel for long term beam operation. This apparently has been the case for CEBAF. However, no physical evidence has been shown in the past. In this contribution, we will report on the recent results concerning the root cause of field emitters in SRF cavities placed in CEBAF tunnel. We will discuss these results in the context of high-reliability and low-cryogenic-loss operation of CEBAF.

Slides THOBB03 [3.768 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THOBB03

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMB025

The Effect of Magnetic Field on the Secondary Electron Yield in the Ultra-High Vacuum Environment

electron, gun, permanent-magnet, synchrotron-radiation

3281

J. Wang, Y. Wang, W. Wei, Y.H. Xu, B. Zhang, T. Zhang, Y.X. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

A secondary electron emission measurement system has been designed and used to study the secondary electron emission (SEE) of different materials with an independently adjustable energy of 50 eV to 5 keV at National Synchrotron Radiation Laboratory. Here, we obtained the characteristics of the SEE yield from Pd film coatings, under the condition of magnetic field and without magnetic field. Then it was analysed that the effect of magnetic field on the secondary electron yield in the ultra-high vacuum environment. The results show that magnetic field shielding is critical to avoid the influence of magnetic field during secondary electron yield (SEY) measurements.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB025

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMB026

Research on Low Secondary Electron Yield Materials for Future Accelerators

electron, laser, proton, synchrotron-radiation

3284

J. Wang, Y. Wang, W. Wei, Y.H. Xu, B. Zhang, T. Zhang, Y.X. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

For future accelerators, such as SPPC (SEYmax <1.2), the build-up of electron cloud generated in the beam pipes considerably affect the stability of particle beams. Therefore, it is critical to look for steady and low secondary electron yield (SEY) material for future high intensity accelerators.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB026

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMB051

Development of Intelligent Alarm Message System at TPS

status, radiation, operation, SRF

3363

C.C. Liang, C.H. Chang, C.H. Chen, J. Chen, J.Y. Chen, Y.-S. Cheng, M.-S. Chiu, S. Fann, C.S. Huang, C.-C. Kuo, T.Y. Lee, Y.C. Lin, Y.-C. Liu, H.-J. Tsai, F.H. Tseng, I.C. Yang, T.-C. Yu
NSRRC, Hsinchu, Taiwan

The traditional alarm systems usually set up/low limit for various signals. When the acquired values exceed the limits, the alarm system would be activated. The proposed system in this article can focus on various possible events with many kinds of signals for response judgments. During alarm calling period, data can also be announced and recorded. The system can also monitor various events according to different time shifts. Integrating LabVIEW, mobile phone, AT-command and Bluetooth communication, the system can handle factory broadcast, sending E-mail and SMS message. The above sound and words messages can be set directly at the home-made software interface. The new intelligent alarm system can eliminate the procedure made by man with the added event recording, system stability improvement and debugging function in wider application fields.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB051

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMR031

Turn-by-Turn Measurements for Beam Dynamics at Vepp-5 Damping Ring

impedance, damping, betatron, lattice

3452

M.F. Blinov, K.V. Astrelina, V.V. Balakin, O.I. Meshkov, A.A. Starostenko
BINP SB RAS, Novosibirsk, Russia
V.L. Dorokhov
BINP, Novosibirsk, Russia

Preinjector complex VEPP-5 is being constructed for high rate production and acceleration of electrons and positrons beams up to energy 510 MeV. Both kinds of particles accumulated in the damping ring and after achieving of needed intensity the beams would be transported alternatively to VEPP-3/VEPP-4M or to BEP/VEPP-2000 colliders. At this paper basic parameters of damping ring presented. All measurements were carried out for electron beam with energy 385 MeV. For turn-by-turn measurements 12 beam position monitors were used. In order to improve precision of measured value NAFF algorithm was applied. For measurements of longitudinal beam profile optical phi-dissector was used.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMR031

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMW012

The Fast Interlock Controller for High Power Pulse Modulator at PAL-XFEL

PLC, controls, interlocks, operation

3561

S.H. Kim, H.-S. Kang, K.H. Kim, S.J. Kwon, H.-S. Lee, S.S. Park, Y.J. Park
PAL, Pohang, Kyungbuk, Republic of Korea
I.S. Ko
POSTECH, Pohang, Kyungbuk, Republic of Korea

Funding: This work is supported by Ministry of Science, ICT(Information/Communication Technology) and Future Planning.
The modulator control system for PAL-XFEL consists of a PLC unit (Programmable Logic Controller) and FPSCM (Fast Pulse Signal Conditioning Module). There are two kinds of interlock, which are dynamic and static interlocks categorized as analogue monitor and control signals, digital monitor and control signals. In case of dynamic interlocks, the internal interface of the PLC unit had to be modified due to operating within 10 ms time response from the interlock event. The fast pulse signal conditioning module is adopted for preconditioning the fast pulse and DC signals that inherently have high noise levels generated from a beam voltage, a beam current and EOLC current. Those EM (Electro-Magnetic) noises are generated by thyratron switching. The amplitude of the thyratron noise is large which causes the problem at the control devices, frequently. In this paper, the test results of the interlock control system will be described.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMW012

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMW019

Concept and Design of the Injection Kicker System for the FAIR SIS100 Synchrotron

kicker, operation, ion, pulsed-power

3582

I.J. Petzenhauser, U. Blell, P.J. Spiller
GSI, Darmstadt, Germany
L.O. Baandrup, H. Bach, N. Hauge, K.F. Laurberg
Danfysik A/S, Taastrup, Denmark
G. Blokesch, M. Osemann
Ampegon PPT GmbH, Dortmund, Germany

The SIS100 synchrotron at GSI, Germany is designed for acceleration of protons and ions. For the injection into the synchrotron a kicker magnet system, which consists of 6 ferrite kicker magnet modules, installed in one vacuum tank with a required vacuum quality better than 10-9 Pa, will be needed. The magnetic field should be 118 mT in a 65 mm gap. These kicker magnet modules will be supplied with 6 separate pulser circuits. Each pulser has to produce a pulse current of up to 7 kA at a PFL (pulse forming line) voltage of 80kV at an impedance of 5.7 Ohm. The rise time has to be 130 ns and the variable pulse length is between 0.5 to 2.0 μs. The design concept for this kicker system from Ampegon PPT and DANFYSIK and the specific challenges will be described.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMW019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMW028

High Voltage Performance of Surface Coatings on Alumina Insulators

kicker, high-voltage, injection, impedance

3603

A. Adraktas, M.J. Barnes, H.A. Day, L. Ducimetière
CERN, Geneva, Switzerland

Alumina insulators and dielectrics are required for a variety of applications in particle accelerators. Their use in high voltage devices, both pulsed and DC, is well established as both insulation and mechanical support. In accelerator equipment the alumina is usually used in ultra-high vacuum and hence charge accumulation can be an issue, especially when the alumina is near to the beam. To address challenges regarding surface flashover and high secondary electron yield in high intensity accelerators, surface treatments and coatings are being considered. This paper presents predictions of the influence of surface coatings, on alumina insulators, upon electric field.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMW028

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMW030

Studies of Impedance-related Improvements of the SPS Injection Kicker System

kicker, impedance, simulation, coupling

3611

M.J. Barnes, A. Adraktas, M.S. Beck, G. Bregliozzi, H.A. Day, L. Ducimetière, J.A. Ferreira Somoza, B. Goddard, T. Kramer, C. Pasquino, G. Rumolo, B. Salvant, L. Sermeus, J.A. Uythoven, L. Vega Cid, W.J.M. Weterings, C. Zannini
CERN, Geneva, Switzerland
F.M. Velotti
EPFL, Lausanne, Switzerland

The injection kicker system for the SPS consists of sixteen magnets housed in a total of four vacuum tanks. The kicker magnets in one tank have recently limited operation of the SPS with high-intensity beam: this is due to both beam induced heating in the ferrite yoke of the kicker magnets and abnormally high pressure in the vacuum tank. Furthermore, operation with the higher intensity beams needed in the future for HL-LHC is expected to exacerbate these problems. Hence studies of the longitudinal beam coupling impedance of the kicker magnets have been carried out to investigate effective methods to shield the ferrite yoke from the circulating beam. The shielding must not compromise the field quality or high voltage behaviour of the kicker magnets and should not significantly reduce the beam aperture: results of these studies, together with measurements, are presented. In addition results of tests to identify the causes of abnormal outgassing are presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMW030

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMW033

Operational Experience of the Upgraded LHC Injection Kicker Magnets

kicker, injection, operation, impedance

3623

M.J. Barnes, A. Adraktas, G. Bregliozzi, S. Calatroni, H.A. Day, L. Ducimetière, B. Goddard, V. Gomes Namora, V. Mertens, B. Salvant, J.A. Uythoven, L. Vega Cid, W.J.M. Weterings, C. Yin Vallgren
CERN, Geneva, Switzerland

During Run 1 of the LHC the injection kicker magnets caused occasional operational delays due to beam induced heating with high bunch intensity and short bunch lengths. In addition, sometimes there were also sporadic issues with microscopic unidentified falling objects, vacuum activity and electrical flashover of the injection kickers. An extensive program of studies was launched and significant upgrades were carried out during long shutdown 1. These upgrades include a new design of a beam screen to both reduce the beam coupling impedance of the kicker magnet, and to significantly reduce the electric field associated with the screen conductors, hence decreasing the probability of electrical breakdown in this region. In addition new cleaning procedures were implemented and equipment adjacent to the injection kickers and various vacuum components were modified. This paper presents operational experience of the injection kicker magnets during Run 2 of the LHC and assesses the effectiveness of the various upgrades.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMW033

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMW038

Prototyping of the ALS-U Fast Kickers

kicker, impedance, coupling, injection

3637

G.C. Pappas, S. De Santis, J.-Y. Jung, T.H. Luo, C. Steier, C.A. Swenson, W.L. Waldron
LBNL, Berkeley, California, USA

Prototyping of major components for the ALS-U kickers is in progress. A tapered stripline kicker has been built for installation and testing in the ALS, and multiple modulator options to meet the fast rise time required for swap out injection have been considered. High voltage feedthroughs that are matched into the multi GHz range are also being studied.
* Pappas et al., "Fast Kicker Systems for ALS-U", Proc. of IPAC'14, Dresden, Germany, MOPME083.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMW038

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMW043

Observation of Beam-induced Abort Kicker Ferrite Heating in RHIC

kicker, quadrupole, proton, impedance

3648

C. Montag, L. Ahrens, K.A. Drees, H. Hahn, J.-L. Mi, C. Pai, J. Sandberg, T.C. Shrey, P. Thieberger, J.E. Tuozzolo, W. Zhang
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
During the FY 2013 RHIC polarized proton run, deterioration of the abort kicker system was observed. The reduced kicks resulted in quenching the superconducting quadrupole Q4 downstream of the beam dump. Frequent re-tuning of the modulator wave form temporarily mitigated the effect, which worsened during the course of the run. Beam-induced heating of the kicker ferrites was evenutally identified as the root cause of this behavior. We report our observations and discuss modifications to the kickers.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMW043

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY001

Design and R&D for the SPring-8 Upgrade Storage Ring Vacuum System

photon, storage-ring, laser, radiation

3651

M. Oishi, T. Bizen, H. Ohkuma, M. Shoji, S. Takahashi, K. Tamura, Y. Taniuchi
JASRI/SPring-8, Hyogo-ken, Japan

Conceptual design report for the SPring-8 upgrade project (SPring-8-II) was published in November of 2014. Vacuum system for the targeted storage ring should handle some fateful boundary conditions, such as miniaturization of vacuum chamber and increase in number of photon absorbers resulting from the multi-bend achromat configuration. Furthermore, reuse of the existing tunnel brings the severe packing factor issue of vacuum components and the time constraints issue of one-year blackout. Considering the above circumstances, a concept of 12-m long vacuum chamber with welded integral structure was proposed to omit in-situ baking. The 12-m long chamber will be evacuated to ultra-high vacuum by ex-situ baking followed by NEG activation, and moved to the tunnel with special thin gate valves at both ends. Recently, the chamber material has been changed from aluminum alloy to stainless steel (SS) from the viewpoints of elimination of aluminum-SS transition space, beam vibration suppression, and superior outgassing property. Trial production of SS chamber is proceeding to establish appropriate manufacturing processes, while focusing on the accuracy of dimension and magnetic permeability.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY001

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY002

Fabrication of Ferrite-Copper Block by Spark Plasma Sintering (SPS)

HOM, cavity, higher-order-mode, plasma

3654

Y. Suetsugu, T. Ishibashi, S. Terui
KEK, Ibaraki, Japan
H. Ishizaki, A. Kimura, T. Sawhata
Metal Technology Co. Ltd., Ibaraki, Japan

A ferrite has been well known as an effective material for absorbing electromagnetic waves. Various types of the ferrite blocks have been actually used in accelerator fields as the higher-order modes (HOMs) absorbers in the vacuum beam pipes. However, one of difficulties in using the ferrite is to bond it to the beam pipes with a sufficient adhesive force, and to assure the contact with a high thermal conductivity in vacuum. The brazing or Hot Isostatic Pressing (HIP) is not so easy owing to a low thermal expansion rate and a relatively low tensile strength of the ferrite. We established a method of fabricating a ferrite block bonded to copper by spark plasma sintering (SPS). The ferrite powders are directly sintered on a copper block in the SPS process together with some metals to relax the thermal stress between them. The sintered ferrite-copper block can be brazed or welded to other metal blocks, or directly on the beam pipes. Here reported are R&D results of the fabrication method, and some experimental results on the properties of the ferrite-copper block.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY002

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY003

Design of the RISP Vacuum Systems

ion, linac, simulation, cryomodule

3657

D. Jeon, J.H. Cho, K.B. Lim, H.J. Son, J. Song, S.W. Yoon
IBS, Daejeon, Republic of Korea
H.S. Choi, T. Ha
PAL, Pohang, Republic of Korea
S.R. In
KAERI, Daejon, Republic of Korea
B.C. Kim, K.P. Kim, K.M. Kim, Y.S. Kim
NFRI, Republic of Korea

The vacuum requirement of the RISP heavy ion accel-erator facility has been derived that meets the beam loss requirement and the vacuum system design is carried out using the 3D Molflow+ code verifying the vacuum re-quirement. We used realistic outgassing values of the materials of the vacuum chambers and beam pipes. We are designing detailed vacuum system specification and configuration including pumps, gate valves, and vacuum gauges along with the interlock system and differential pumping stations.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY003

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY006

Analysis and Testing of a New RF Bridge Concept as an Alternative to Conventional Sliding RF Fingers in LHC

operation, impedance, ion, alignment

3660

J. Perez Espinos, C. Garion
CERN, Geneva, Switzerland

RF fingers are used as transition elements in beam vacuum line interconnections to ensure the continuity of the vacuum system wall within acceptable beam stability requirements. The RF fingers must absorb and compensate longitudinal, angular and transversal misalignments due to both thermal effects, during bake-out or cooldown processes, and mechanical movements during assembly, alignment, commissioning and operation phases. The new RF bridge concept is based on a deformable thin-walled structure in copper beryllium, which fulfils the above requirements without the need of sliding contacts. Mechanical tests have been carried out to characterize the response and the lifetime of such a component under different loading conditions. In addition, finite element models have been used to estimate the behaviour. The influence of different material grades and heat treatments on the reliability is presented. The paper includes a detailed analysis of the prototyping and testing phases that have led to a final design of the system, qualified on a dedicated test bench, for the collimator vacuum modules of LHC.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY006

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY007

Vacuum Performance of Amorphous Carbon Coating at Cryogenic Temperature with Presence of Proton Beams

electron, cryogenics, experiment, simulation

3663

R. Salemme, V. Baglin, G. Bregliozzi, P. Chiggiato
CERN, Geneva, Switzerland

Amorphous carbon (a-C) coating is the baseline electron multipacting mitigation strategy proposed for the Inner Triplets (IT) in the High Luminosity upgrade of the Large Hadron Collider (HL-LHC). As of 2014, the COLD bore EXperiment (COLDEX) is qualifying the performance of a-C coating at cryogenic temperature in a LHC type cryogenic vacuum system. In this paper, the experimental results following a cryogenic vacuum characterization of a-C coating in the 5 to 150 K temperature range are reviewed. We discuss the dynamic pressure rise, gas composition, dissipated heat load and electron activity observed within an accumulated beam time of 9 Ah. The results of dedicated experiments including pre-adsorption of different gas species (H2, CO) on the a-C coating are discussed. Based of phenomenological modeling, up-to-date secondary emission input parameters for a-C coatings are retrieved for electron cloud build-up simulations. Finally, first implications for the HL-LHC ITs design are drawn.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY007

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY008

Mechanical and Vacuum Stability Studies for the LHC Experiments Upgrade

ion, experiment, detector, simulation

3667

J. Sestak, G. Bregliozzi, P. Chiggiato
CERN, Geneva, Switzerland

In April 2015, the Large Hadron Collider (LHC) has entered its second operational period that will last for 3 years with expected end of the operations at the beginning of 2019. Afterward, the LHC will undergo a long shutdown (LS2) for upgrade and maintenance. The four LHC experiments, ATLAS, ALICE, CMS and LHCb, will experience an important upgrade too. From the design point of view, the LS2 experimental beam vacuum upgrade requires multi-disciplinary approach: based on the geometrical envelope defined by experiment, the vacuum chambers size and shape must be optimized. This included Monte Carlo pressure profile simulations and vacuum stability studies in order to meet the specific pressure requests in the interaction region. Together with vacuum studies the structural analysis are performed in order to optimise chambers thickness and position of the operational and maintenance supports. The material selection for vacuum chambers in the experimental area follows the CERN ALARA (as low as reasonably achievable) principle. This paper gives an overview of the LS2 experimental vacuum sectors upgrades. The most extensive design studies, done for the two experiments CMS and ALICE are discussed in detail.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY008

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY009

Coaxial Wire Method Adapted to Weakly Coupled Resonator Mode for LHC RF Fingers Evaluation

resonance, impedance, coupling, cavity

3670

C. Vollinger, F. Caspers, T. Kaltenbacher
CERN, Geneva, Switzerland

In high intensity particle accelerators, RF contact fingers are commonly used to carry the beam induced image current. In addition, they reduce beam impedance by shielding the outer bellows required to compensate mechanical displacements between components. In order to assess the resulting beam impedance from a specific bellow/RF finger configuration, RF measurements are routinely carried out. During these measurements, it was observed that cavity modes in the volume between the fingers and the bellow undulation arise. These resonances occur at significantly higher frequencies than the expected frequency range of interest. Due to their broadband nature, the tails of the imaginary part of these resonances reach into the lower frequency range of interest where it contributes to the beam coupling impedance of the device. For proper evaluation of this contribution, a time domain delay technique in TDT (time domain transmissiometry) was used in order to overcome shortcomings that arise if the classical coaxial wire method is applied to these structures. We present the theory of our method and discuss it in view of the data measured on deformable fingers that were studied for the LHC.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY009

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY011

Chamber Upgrade for EPU48 in TPS

storage-ring, synchrotron, synchrotron-radiation, radiation

3676

I.C. Sheng, C.K. Chan, C.-C. Chang, C.M. Cheng, Y.T. Cheng, J. -Y. Chuang, Y.M. Hsiao, Y.T. Huang, C. Shueh, L.H. Wu, I.C. Yang
NSRRC, Hsinchu, Taiwan

Due to high total power and power density in Taiwan Photon Source (TPS) of EPU48 (Elliptical Polarized Undulator) in double minimum sector, we fabricate a new Aluminum vacuum chamber to increase sufficient room for synchrotron radiation to pass through without damage the storage ring chamber. A new method of in-site replacement of bending chamber is also presented, the result of this replacement procedure shows that it is very cost-effective as well as good UHV vacuum quality.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY011

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY013

Laser-Beam Welding for a TPS Beam-Position Monitor

laser, interface, controls, target

3679

Y.T. Huang, C.-C. Chang, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu
NSRRC, Hsinchu, Taiwan

The TPS beam-position monitor has two feedthroughs in one flange structure. The hermetic seal was formed with laser-beam welding (LBW). Nd-YAG LBW was adopted to weld a button electrode with a feedthrough; CO2 LBW served for a feedthrough and a flange, Fig. 1. A robotic arm was used for Nd-YAG LBW so that it could accomplish the complicated geometry of the welded joint. Although the CO2 laser was not coordinated with a robotic arm, fixtures were made to implement a circular welded joint the same as welding the feedthrough into a flange. For not only Nd-YAG but also CO2 LBW, the cover gas is the major key that avoids oxidation from atmospheric oxygen and maintains shiny weld beads. Taguchi methods were exploited to find the appropriate parameters for the Nd-YAG pulsed laser, for instance, the laser power, pulse-filling time, frequency etc.. This paper presents the process and details of laser-beam welding of two types for a beam-position monitor.
Laser beam weld, Nd-YAG, CO2, POWER, filling time, beam position monitor

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY013

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY014

Study of the Non-evaporable Ti-Zr-V Films Grown on Different Materials

electron, experiment, synchrotron-radiation, booster

3682

L.H. Wu, C.M. Cheng, Y.T. Huang, S.Y. Perng, I.C. Sheng, C. Shueh
NSRRC, Hsinchu, Taiwan

The non-evaporable (NEG) Ti-Zr-V films were coated on the different vacuum-chamber materials, including the extruded aluminum samples (Al), the extruded seamless stainless steel samples (S.S.), CuCrZr alloys, and oxygen-free copper (OFC) plates. The NEG films were fabricated by using the direct current (DC) sputtering method. The secondary electron microscopy images showed that the morphology of NEG films was different on these various substrates. The thermal analysis (TA) presented that exothermic reaction happened by heating the samples.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY014

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY015

Measurement of the Pressure in the TPS Booster Ring

booster, electron, storage-ring, ion

3685

C.M. Cheng, C.K. Chan, G.-Y. Hsiung, Y.T. Huang, I.C. Sheng, L.H. Wu, I.C. Yang
NSRRC, Hsinchu, Taiwan

The booster ring of Taiwan Photon Source (TPS) is designed to provide full energy injection 3 GeV ramped up from 150 MeV with a small beam emittance. It is a synchrotron accelerator of circumference 496.8 m. The vacuum chamber through the magnets is made of thin stainless-steel tube extruded to an elliptical cross section of inner diameters 35 mm and 20 mm, and thickness 0.7 mm. The other chambers have standard 35CF round tube. The vacuum system was baked in the first installation. Because the residual stress of the stainless-steel elliptical tubing caused the magnetic field to become unstable, all elliptical tubing was removed for annealing to proceed, and reinstalled without baking. The ultimate pressure and data for the residual gas are shown as follows.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY015

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY016

Graphene Coating for the Reduction of the Secondary Electron Yield

electron, cavity, proton, framework

3688

B.S. Sian, G.X. Xia, G.L. Yu
UMAN, Manchester, United Kingdom
I. Kinloch, L. Lin, V. Valles
University of Manchester, Manchester, United Kingdom
O.B. Malyshev, R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
O.B. Malyshev, R. Valizadeh, G.X. Xia
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Secondary electron emission is a limiting factor for a performance of many instruments ranging from small gauges and detectors to waveguides and charged particle accelerators. There have been several methods of reducing this effect, e.g. the method of using a material with a low Secondary Electron Yield (SEY) or thin film coating with such a low SEY material. This paper describes the effect of SEY mitigation with graphene coatings on aluminium substrate. The maximum SEY (dmax) was decreased from 2.4 for bare aluminium to 1.4 with a graphene coating. Measurements were taken using an electron gun and a Faraday cup, the electron energies varied between 80 eV and 1 keV with a bias of -18 V on the sample. Other biases of -3, -5, -9, -25, -50 and -75 V were also tested however there was no effect on the SEY.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY016

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY017

A Comparison of Surface Properties of Metallic Thin Film Photocathodes

electron, laser, survey, cathode

3691

S. Mistry, M.D. Cropper
Loughborough University, Leicestershre, United Kingdom
A.N. Hannah, L.B. Jones, K.J. Middleman, B.L. Militsyn, T.C.Q. Noakes, R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

In this work physical vapour deposition magnetron sputtering has been employed to deposit metallic thin films onto Cu, Mo and Si substrates. The use of metallic thin films offers several advantages: (i) metal photocathodes present a fast response time and a relative insensitivity to the vacuum environment (ii) metallic thin films when prepared and transferred in vacuum can offer smoother and cleaner cathode surfaces. The photocathodes developed here will ultimately be used to drive NCRF guns such as that used in VELA and the proposed CLARA light source test facility. The samples grown on Si substrates were used to investigate the morphology and thickness of the film. The samples grown onto Cu and Mo substrates were analysed and tested as photocathodes in a surface characterisation chamber, where X-Ray photoelectron spectroscopy was employed to determine surface chemistry and a Kelvin probe apparatus used to determine work function. QE measurements were enabled using a 266 nm UV laser.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY017

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY018

Benchmarking and Calibration of Monte Carlo Vacuum Simulations with SynRad and MolFlow+

photon, storage-ring, experiment, scattering

3695

J.A. Carter
ANL, Argonne, Ilinois, USA

The APS-Upgrade project is using SynRad and MolFlow+ to evaluate the vacuum system design for the future 6 GeV, 200 mA APS-Upgrade storage ring. The goal of this work is to explore PSD outgassing predictions from the two programs in order to build confidence in pressure calculations for the APS-U storage ring vacuum system. A study is performed on calibrating PSD measurements for aluminum vacuum chambers and then applying them to APS-U vacuum system calculations. The study reveals that a PSD measurement may not reveal a single unique behavior for a vacuum material and that multiple sources should be considered for vacuum calculations.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY018

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY024

Upgrade of a UHV Furnace for 1700 C Heat Treatment and Processing of Niobium Samples

niobium, power-supply, radiation, radio-frequency

3709

J. Conrad, L. Alff, R. Grewe, T. Kürzeder, M. Major, N. Pietralla
TU Darmstadt, Darmstadt, Germany
F. Hug
IKP, Mainz, Germany
S.T. Sievers
MIT, Marburg, Germany

Funding: Supported by the German Federal Ministry for Education and Research (BMBF) under Grant No. 05H15RDRBA
In 2005 a high temperature vacuum furnace was put into operation at the Institute for Nuclear Physics at the Technische Universität Darmstadt. It has been designed for firing pure Niobium at temperatures of up to 1870 C. Until now several Nb cavities have been heat treated at 850 C with a proven record of success. The current focus of research in improving the superconductive characteristics of accelerator cavities is on new materials such as Nb3Sn or NbN or on the doping of Nb surfaces with nitrogen, so called N2-Doping. The surface preparations generally take place at temperatures of not more than 1000 C. To study phenomena that occur at higher temperatures, like the formation of delta-phase NbN at 1300 to 1700 C, it is planned to refurbish the UHV furnace and use it for corresponding studies. We will report on the design of a new annealing pot and a sample holder and give a review on our first experiences with the upgraded furnace.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY024

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY025

Mechanical Integration of the IFMIF-EVEDA Radio Frequency Quadrupole

rfq, interface, site, alignment

3712

P. Mereu, E.A. Macri, M. Mezzano
INFN-Torino, Torino, Italy
P. Bottin, E. Fagotti, A. Pisent
INFN/LNL, Legnaro (PD), Italy
D. Gex
F4E, Germany

The Linear IFMIF Prototype Accelerator, the high intensity deuteron linac compact demonstrator of the IFMIF machine, is in an advanced installation phase at BA site (Rokkasho, Japan), within a European-Japan collaboration coordinated respectively by F4E and JAEA. The RFQ (5 Mev, 130 mA) is an Italian in-kind contribution under the responsibility of INFN. Is it a 9,8 m-long structure made of 18 modules, pre-assembled in three parts. The various aspects of the RFQ integration inside the LIPAc are presented here, with details about the various functional services of the RFQ, the different interfaces with other sub-components of the linac and with the building and the structural validation through the seismic analysis. Some peculiar aspects related to the installation of the RFQ are also detailed (i.e. the handling tooling, precise positioning jigs).

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY025

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY030

How to Manage a Large Scale Beam Line Consolidation in a Highly Activated Area?

radiation, operation, controls, target

3721

S. Evrard, J.L. Grenard, E. Harrouch, A. Herve, A. Pardons, Y. Pira, Y.D.R. Seraphin, C. Theis, H. Vincke
CERN, Geneva, Switzerland

The TDC2/TCC2 consolidation is a good example showing how the complexity of interventions in high radiation areas has increased over the last five years. Due to its duration, its dispersion, the diversity of the teams involved, the fixed deadlines, the risks and external constraints, this worksite prefigures large scale-interventions in the LHC during long shutdown 2 (LS2) and even more LS3. The paper describes the three main project phases: preparation, execution (including monitoring and control) and closure emphasizing the indispensable steps in each stage. It also explains why integrating scope, schedule and dose into a single baseline is of prime importance and shows how to manage and monitor the radiation safety performance of the various interventions throughout the execution phase. Eventually, some recommendations are formulated in order to better accommodate the design of high radiation areas to their operation and maintenance constraints.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY030

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMY040

Laser Cooling of Relativistic Highly Charged Ions at FAIR

laser, ion, detector, synchrotron

3747

D.F.A. Winters, O. Boine-Frankenheim, L. Eidam, T. Kühl, P.J. Spiller, T. Stöhlker
GSI, Darmstadt, Germany
T. Beck, G. Birkl, D. Kiefer, T. Walther
TU Darmstadt, Darmstadt, Germany
M.H. Bussmann, U. Schramm, M. Siebold
Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiation Physics, Dresden, Germany
V. Hannen, D. Winzen
Westfälische Wilhelms-Universität Münster, Institut für Kernphysik, Münster, Germany
M. Löser
HZDR, Dresden, Germany
X. Ma, W.Q. Wen
IMP/CAS, Lanzhou, People's Republic of China

An overview of recent laser cooling activities with relativistic heavy ion beams at the ESR (GSI, Darmstadt, Germany) and the CSRe (IMP, Lanzhou, China) storage rings will be presented. Some of the latest results will be shown and new developments concerning xuv-detector systems and cw and pulsed laser systems will be addressed. Finally, plans for laser cooling (& spectroscopy) at the future facility FAIR in Darmstadt will be presented, focusing on the SIS100.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY040

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR033

Integration and Testing of 3 Consecutive CLIC Two-Beam Modules

alignment, collider, operation, feedback

3856

A.L. Vamvakas, M. Aicheler, S. Döbert, M. Duquenne, H.M. Durand, M. Sosin, J.I. Väinölä
CERN, Geneva, Switzerland
V. Rude
ESGT-CNAM, Le Mans, France

CLIC (Compact LInear Collider) is a study of a 50 km long linear electron-positron collider, consisting of ap-proximately 20,000 repetitive 2 m long modules. Micron level manufacturing and alignment tolerances are re-quired for the RF and magnet components due to the nanometre beam size and luminosity goal. The effect of thermal, vacuum and mechanical loads needs to be as-sessed, both in transient and in steady state conditions. The dynamic behaviour of mock-ups was investigated on the prototype two-beam module. Two additional two-beam modules are installed to further investigate the interconnections between them, in a machine-like envi-ronment. The array of three consecutive modules allows for alignment tests of the module sequence, while thermal and vacuum tests can be executed simultaneously. A transportation experiment is foreseen, investigating the feasibility of installing prealigned modules. Finally, new design of components is being tested, based on the expe-rience gathered from the first module and leading to a new generation module.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR033

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR036

Updates on the Sliding Contact Cooling ILC Positron Source Target Development

target, positron, undulator, radiation

3865

W. Liu, D.S. Doran, R.A. Erck, G.R. Fenske, W. Gai, V.J. Guarino
ANL, Argonne, Illinois, USA

The R&D of the baseline positron source target for ILC is still ongoing after TDR due to the uncertainty of rotating vacuum seal and water cooling system of the fast spinning target wheel. Different institutes around the globe have proposed different approaches to tackle this issue. A spinning target wheel system with sliding contact cooling has been proposed by ANL. The proposed system eliminated the needs of rotating vacuum seal by using magnetic torque coupler to drive the solid spinning wheel target. The energy deposited from positron production process is taken away via cooling pads sliding against the spinning wheel. A full size test wheel has been built and some initial tests have been done with promising outcomes. Results of these tests are presented in this paper along with a plan for developing a prototype.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR036

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR041

High Gradient Properties of a CLIC Prototype Accelerating Structure made by Tsinghua University

operation, timing, accelerating-gradient, experiment

3874

X.W. Wu, H.B. Chen, J. Shi
TUB, Beijing, People's Republic of China
T. Higo, S. Matsumoto
KEK, Ibaraki, Japan
W. Wuensch
CERN, Geneva, Switzerland

A CLIC prototype structure, T24_THU_#1, was recently high-gradient tested at KEK X-band test stand, Nextef. The copper parts of this 24-cell TW structure were delivered from CERN, were bonded and brazed, bench-tested and tuned in Tsinghua University. The aim of this test was not only to verify the cavity high-gradient properties under 100 MV/m but also to study the breakdown phenomenon in high gradient. High power test results were presented and breakdown rate under 100 MV/m was compared to previously-tested CLIC prototype structures. The assembly capability of Tsinghua University for X-band high gradient structures was validated by the good high gradient performance of T24_THU_#1.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR041

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR042

New Quantity Describing the Pulse Shape Dependence of the High Gradient Limit in Single Cell Standing-Wave Accelerating Structures

operation, radiation, data-analysis, experiment

3878

J. Shi, H.B. Chen, X.W. Wu
TUB, Beijing, People's Republic of China
V.A. Dolgashev
SLAC, Menlo Park, California, USA
A. Grudiev, W. Wuensch
CERN, Geneva, Switzerland
Y. Higashi
KEK, Ibaraki, Japan
B. Spataro
INFN/LNF, Frascati (Roma), Italy

A new quantity has been developed to study the relationship among the breakdown rate, the pulse width and the gradient. Difference pulse shapes can be treated by introducing a Green's function. This paper describes the quantity and the results while it is applied to the data of many high-power test runs of different single-cell standing wave accelerating structures. A remarkably similar relationship between the new quantity and breakdown rate is observed from all of the test results.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR042

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR043

High Power Test of X-band Single Cell HOM-free Choke-mode Damped Accelerating Structure made by Tsinghua University

cavity, operation, HOM, coupling

3881

X.W. Wu, H.B. Chen, J. Shi
TUB, Beijing, People's Republic of China
T. Abe, T. Higo
KEK, Ibaraki, Japan
W. Wuensch, H. Zha
CERN, Geneva, Switzerland

As an alternative design for CLIC main accelerating structures, X-band choke-mode damped structures had been studied for several years. However, the performance of choke-mode cavity under high power is still in lack of research. Two standing wave single cell choke-mode damped accelerating structures with different choke dimensions which are working at 11.424 GHz were designed, manufactured and bench tested by accelerator group in Tsinghua University. High power test was carried out on it to study the breakdown phenomenon in high gradient. A single cell structure without choke which almost has the same inner dimension as choke-mode cavity will also be tested to make a comparison and study how the choke affects high-gradient properties.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR043

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR045

Analytical Estimation of ATF Beam Halo Distribution

scattering, emittance, electron, damping

3888

D. Wang, J. Gao
IHEP, Beijing, People's Republic of China
P. Bambade
LAL, Orsay, France
T. Naito
KEK, Ibaraki, Japan

Funding: Work supported by the National Foundation of Natural Sciences (11505198 and 11575218)
Halo distribution is a key topic for background study. This paper has developed an analytical method to give an estimation of ATF beam halo distribution. The equilibrium particle distribution of the beam tail in the ATF damping ring is calculated analytically with different emittance and different vacuum degree. The analytical results agree the measurements very well. This is a general method which can be applied to any electron rings.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR045

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR051

Beam Based Measurements to Check Integrity of LHC Dump Protection Elements

extraction, kicker, proton, operation

3908

C. Bracco, W. Bartmann, M.A. Fraser, B. Goddard, A. Lechner
CERN, Geneva, Switzerland

LHC operation is approaching its nominal operating goals and several upgrades are also being prepared to increase the beam intensity and brightness. In case of an asynchronous beam dump at 6.5 - 7 TeV a non-negligible fraction of the stored energy (360 MJ during nominal operation) will be deposited on the protection elements (TCDQ and TCDS) located downstream of the extraction kickers. These elements are designed to protect the machine aperture from the large amplitude particles resulting from the asynchronous dump. A number of checks and measurements with beam have been worked out to verify the integrity of these elements, after a potentially harmful event, without opening the machine vacuum. Details on measurements and simulations performed to evaluate the validity of the proposed method are presented in this paper.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR051

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW005

A Study of CsK2Sb Multi-alkali Photocathode by Ultraviolet Photoelectron Spectroscopy at UVSOR

cathode, electron, laser, experiment

3934

M. Urano, M. Kuriki, K. Negishi
HU/AdSM, Higashi-Hiroshima, Japan
T. Konomi, Y. Seimiya, N. Yamamoto
KEK, Ibaraki, Japan

Photocathode is one of the most important components in the next-generation accelerators, especially based on linear accelerators. Photocathode performance depends not only on electronic state in its bulk material but also on the surface condition. CsK2Sb multi-alkali photocathode is a candidate for the high brightness electron source because of its high quantum efficiency by green laser and its high robustness. We have carried out an UPS (UV Photoelectron Spectroscopy) experiment at UVSOR facility, synchrotron radiation light source in Aichi Japan. We have compared the UPS spectra among several samples, each one has a different quantum efficiency, and try to find physics which decide photocathode's performance. In this case, we focused some characters correlated to the quantum efficiency. I'm going to present a result of this analysis.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW005

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW006

A Study of Operational Lifetime of CsK2Sb Photo-cathode

cathode, laser, electron, storage-ring

3938

A. Yokota, R. Kaku, M. Kuriki, K. Negishi, M. Urano
HU/AdSM, Higashi-Hiroshima, Japan
Y. Seimiya
KEK, Ibaraki, Japan

A high performance electron beam generated with a laser photo-cathode is one of the most important pieces in the advanced accelerator. Because the CsK2Sb photo-cathode is robust with more than 10 % quantum efficiency (QE) by green laser (532nm), it is considered to be the best candidates of the cathode for Energy Recovery Lin-ac (ERL) and Free Electron Laser (FEL) requiring a high brightness beam. We developed a system to evaporate the cathode as a thin film in vacuum to study the cathode performance. The cathode operational lifetime regarding not only on time, but also extracted charge density was studied. We found the lifetime is long enough for practical use in an accelerator.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW006

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW008

DC Photoemission Gun Upgrade at the Compact ERL

gun, operation, high-voltage, FEL

3944

N. Nishimori, R. Hajima, R. Nagai
JAEA, Ibaraki-ken, Japan
Y. Honda, T. Miyajima, T. Uchiyama, M. Yamamoto
KEK, Ibaraki, Japan
M. Mori
JAEA/Kansai, Kyoto, Japan

Funding: This work is partially supported by a JSPS Grant-in-Aid for Scientific Research in Japan (15H03594).
The DC photoemission gun at the compact ERL (cERL) has stably provided beam for ERL commissioning and laser Compton scattering experiments since April 2013. The operational voltage has however been limited to 390 kV due to failures of two segments out of the ten segmented insulator. In order to recover 500 kV operation, we installed an additional two segmented insulator on the existing ten segmented insulator during summer shutdown in 2015. The details of the gun upgrade and the operational experience of the upgraded cERL gun will be presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW008

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW011

The Measurement System of the Electron Gun with Double-anode Structure

gun, cathode, electron, high-voltage

3954

F.L. Shang, J. Li, L. Shang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: National Natural Science Foundation of China(11175181); National Natural Science Foundation of China(10875116)
The double-anode structure with an intermediate electrode has been proposed to overcome the strong space-charge force on the cathode and improve the transverse focusing, which make the goal of high perveance and high compression ratio achieved. This gun plays a key role as the external injecting electron source of the independently-tunable-cells (ITC) RF gun. In order to understand the quality of the beam, a measurement system has been designed. The papers present the measurement system and the result of the test.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW011

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW015

Study of the Performance of Cs2Te Cathodes in the PHIN RF Photoinjector using Long Pulse Trains

cathode, operation, laser, electron

3960

C. Heßler, E. Chevallay, S. Döbert, V. Fedosseev, F. Friebel, I. Martini, M. Martyanov, H. Neupert, V. Nistor, M. Taborelli
CERN, Geneva, Switzerland

The drive beam of CLIC requires unusually high peak and average currents which is challenging for the electron source. As an alternative to the thermionic electron gun foreseen in the baseline design, a photoinjector option is under study at CERN using the PHIN photoinjector, which was designed for a bunch charge of 2.3 nC and 1200 ns train length. During operation with nominal train length in 2014, a large pressure increase in the vacuum system, attributed to a heating of the Faraday cup, caused a degradation of the photocathode. To overcome this problem a vacuum window has been installed to separate the Faraday cup from the rest of the vacuum system. In addition the train length has been further increased to 1600 ns to advance the beam parameters towards CLIC requirements. In this paper recent improved photocathode lifetime measurements carried out under these new conditions will be presented and compared with earlier measurements. Furthermore, the utilized Cs2Te cathode has been analyzed with X-ray Photoelectron Spectroscopy (XPS) before and after its usage in PHIN to get a better understanding of photocathode surface deterioration effects, which will also be discussed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW015

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW038

First Results from Two Novel In-vacuum Magnetic Field Measurement Devices as Built at HZB

feedback, undulator, controls, shielding

4028

J. Bahrdt, H.-J. Bäcker, J. Bakos, H. Bieder, W. Frentrup, A. Gaupp, S. Gottschlich, C. Kuhn, C. Rethfeldt, M. Scheer, B. Schulz
HZB, Berlin, Germany

The characterization of cryogenic in vacuum permanent magnet undulators with periods less than 20 mm and correspondingly narrow gaps requires new in-vacuum measurement systems. The positioning accuracy of the HZB in-vacuum Hallprobe bench has substantially been improved (a few μm) with appropriate feedback systems. A new in-vacuum cable tray has been developed. Another system for field integral measurements, an in-vacuum moving wire, is under commissioning. Both devices are presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW038

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW040

Insertion Devices for Spring-8 Upgrade Project

undulator, electron, storage-ring, polarization

4035

T. Tanaka, T. Hasegawa, R. Kinjo
RIKEN SPring-8 Center, Hyogo, Japan
T. Bizen, A. Kagamihata, H. Kishimoto, H. Ohashi, T. Seike
JASRI/SPring-8, Hyogo, Japan
S. Yamamoto
KEK, Tsukuba, Japan

In the upcoming major upgrade project of SPring-8 (SPring-8-II) planned in the early 2020's, the electron energy will be reduced from 8 GeV to 6 GeV and the straight sections will be shortened by nearly 2 m to accommodate more magnets, for the purpose of reducing the emittance down to around 100 pm.rad. The insertion devices (IDs) currently installed in SPring-8 are not compatible with the above upgrade plan, and thus most of them should be replaced with new ones optimized in the new storage ring, or at least be shortened to fit into the new straight sections. We report the status of R&Ds toward realization of IDs for SPring-8-II, such as shortening the magnetic period, reforming the fundamental structure of IDs to reduce the total cost and manufacturing lead time, and refurbishment of existing IDs for shorter lengths.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW040

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW046

Status of Insertion Device Measurement Systems at MAX IV Laboratory

insertion, insertion-device, controls, undulator

4047

M. Ebbeni, H. Tarawneh, A. Thiel
MAX IV Laboratory, Lund University, Lund, Sweden

An insertion device lab was setup at MAX IV Laboratory and the production of insertion devices, mainly out-of-vacuum is ongoing and aided by new magnetic measurement systems. A new 5.5 m long Hall probe bench is used for field map measurements and a new hybrid flip coil and stretch wire system will be used for field integrals of full devices as well as individual magnet blocks characterisation. This paper describes these magnetic measurement systems and their achieved and expected performance.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW046

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW049

Status of Insertion Devices at Taiwan Photon Source

undulator, radiation, photon, polarization

4054

T.Y. Chung, C.-H. Chang, C.H. Chang, M.-S. Chiu, J.C. Huang, C.-S. Hwang, J.C. Jan, C.-C. Kuo, Y.-C. Liu, F.H. Tseng, C.K. Yang
NSRRC, Hsinchu, Taiwan

The storage ring of Taiwan Photon Source (TPS) has eighteen short straight sections (length 7 m) and six long straight sections (length 12 m). In phase I, three elliptically polarized undulators of type APPLE II and seven in-vacuum undulators, which included four in-vacuum undulators and two elliptically polarized undulators in three double mini-βy sections, were installed. Commissioning of the insertion devices began in 2015 November. The influence of insertion devices on the electron beam and the results after compensation are presented. Problems during the commissioning induced by the electron beam and by radiation, and their solutions, are also explained. For insertion devices in phase II and for devices developed in TPS, the preliminary designs are presented herein, to cover from the VUV to the hard X-ray region.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW049

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW052

Recent Magnetic Measurement Activities at NSLS-II Insertion Device Laboratory

electron, undulator, synchrotron, radiation

4063

M. Musardo, P.L. Cappadoro, O.V. Chubar, T.M. Corwin, H.C. Fernandes, D.A. Harder, D.A. Hidas, C.A. Kitegi, B.N. Kosciuk, W. Licciardi, J. Rank, C. Rhein, T. Tanabe
BNL, Upton, New York, USA

National Synchrotron Light Source II (NSLS-II) at Brookhaven National Laboratory (BNL) is a new 3 GeV third generation electron storage ring designated to provide extremely intense beams of X-ray, ultraviolet, and infrared light for basic and applied research. Insertion devices (IDs) play a significant role in achieving the high performance demands of NSLS-II. An accurate magnetic characterization and proper corrections of these devices are essential activities in the development of a state-of-the-art light source facility. This paper describes the results of the latest magnetic measurement activities at the NSLS-II ID laboratory.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW052

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW054

Cumulative Damage of Ultrafast Laser Pulses

laser, experiment, site, electron

4066

A. Hanuka, L. Schächter
Technion, Haifa, Israel
R.J. England, I.V. Makasyuk, K. Soong, K.P. Wootton, Z. Wu
SLAC, Menlo Park, California, USA

We demonstrate experimentally that damage threshold fluence (DTF) for fused silica changes with the number of femtosecond laser (10Hz 600Hz, 655 fs, 800nm) shots. Based on the experimental data we were able to develop a model which indicates that the change in DTF varies with number of shots logarithmically (ln^p) up to a critical value. Above this value, DTF approaches an asymptotic value. Both DTF for a single shot and the asymptotic value as well as the critical value where this happens are extrinsic parameters dependent on the configuration (repetition rate, pressure and geometry near or at the surface). Indications are that the power of this dependence (p) is an intrinsic parameter independent of the configuration.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW054

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOY028

Operational Status of HLS-II

operation, cavity, storage-ring, electron

4155

J.Y. Li, G. Huang, W. Wei, W. Xu, K. Xuan, Y.L. Yang, Z.R. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

After a major renovation, the Hefei light source (HLS), renamed HLS_II, was brought into operation in the beginning of 2015. The operational result shows that the HLS-II not only provides much brighter synchrotron radiation beam for various users, but also shows much higher reliability than the old light source. This paper first gives an overview of the HLS-II. The overall performance of the light source is then summarized in this paper. Some measured key parameters of the light source, including emittance, orbit stability, beam lifetime and so on, are also presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOY028

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOY035

Machine Protection and Safe Operation of LIPAc Linear Accelerator

operation, rfq, linac, SRF

4178

A. Marqueta, J. Knaster, K. Nishiyama
IFMIF/EVEDA, Rokkasho, Japan
P.-Y. Beauvais, H. Dzitko
F4E, Germany
P. Cara
Fusion for Energy, Garching, Germany
H. Kobayashi
KEK, Ibaraki, Japan
I. Podadera
CIEMAT, Madrid, Spain

A Li(d, xn) fusion relevant neutron source with a broad peak at 14 MeV is indispensable to characterize and qualify suitable structural materials for the plasma facing components in future fusion reactors. LIPAc (Linear IFMIF Prototype Accelerator), presently under its installation and commissioning phase in Rokkasho, will validate the concept of a 40 MeV deuteron accelerator with its 125 mA CW and 9 MeV deuteron beam for a total beam average power of 1.125 MW. The Machine Protection System (MPS) of LIPAc provides the essential interlock function of stopping the beam in case of excessive beam loss or other hazardous situations. However, approaching LIPAc beam commissioning Phase B (including RFQ powered by total 1.6 MW RF power) a risk analysis has been performed on all major technical systems to identify the sources of risk, apply the necessary countermeasures and enhance accelerator availability, avoiding unnecessary beam stop triggers and allowing a fast beam recovery whenever possible. The overall strategy for the machine protection at LIPAc is presented in this paper.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOY035

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOY036

A New Fast RF Trip Diagnostic System in SSRF

diagnostics, cavity, pick-up, klystron

4182

S.J. Zhao, Q. Chang, H.T. Hou, Z. Li, K. Xu, W.Z. Zhang, Zh.G. Zhang, Y.B. Zhao, X. Zheng
SINAP, Shanghai, People's Republic of China

A RF trip diagnostic system is essential to find out the trip source when a trip happened. In this paper, a fast RF trip diagnostic system, in storage ring RF system of SSRF, is reported. This system includes a synchronous acquisition recorder to sampling the trip data and a trip server to analysis the data. The recorder has more than 100 channels and maximum sampling rate of each channel is up to 60 MSPS. High precision I/Q cards are designed to detect RF signals. Trip server has been developed to process the trip data.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOY036

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)