IBIC2018 - List of Keywords (electron)

Paper	Title	Other Keywords	Page
MOOA02	Noise in Radio/Optical Communications	electronics, radio-frequency, optics, feedback	1
	M. Vidmar University of Ljubljana, Faculty of Electrical Engineering, Ljubljana, Slovenia
	Noise is a random signal that affects the performance of all electronic and/or optical devices. Although the sources of different kinds of noise have their backgrounds in physics, engineers dealing with noise use different methods and units to specify noise. The intention of this tutorial is to describe the main effects of noise in electronics up to optical frequencies while providing links between the physics and engineering worlds. In particular, noise is considered harmful while degrading the signal-to-noise ratio or broadening the spectrum of signal sources. On the other hand, noise can be itself a useful signal. Finally, artificially generated signals that exhibit many properties of random natural noise are sometimes required.
	Slides MOOA02 [3.742 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOOA02
About •	paper received ※ 28 August 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOB03	Upgrade and Status of Standard Diagnostic-Systems at FLASH and FLASHForward	FEL, diagnostics, electronics, cavity	13
	N. Baboi, H.T. Duhme, O. Hensler, G. Kube, T. Lensch, D. Lipka, B. Lorbeer, Re. Neumann, P.A. Smirnov, T. Wamsat, M. Werner DESY, Hamburg, Germany
	Electron beam diagnostics plays a crucial role in the precise and reliable generation of ultra-short high bril-liance XUV and soft X-ray beams at the Free Electron Laser in Hamburg (FLASH). Most diagnostic systems monitor each of up to typically 600 bunches per beam, with a frequency of up to 1 MHz, a typical charge be-tween 0.1 and 1 nC and an energy of 350 to 1250 MeV. The diagnostic monitors have recently undergone a major upgrade. This process started several years ago with the development of monitors fulfilling the requirements of the European XFEL and of the FLASH2 undulator beamline and it continued with their installation and commissioning. Later they have been further improved and an upgrade was made in the old part of the linac. Also the FLASHForward plasma-wakefield acceleration experiment has been installed in the third beamline. This paper will give an overview of the upgrade of the BPM, Toroid and BLM systems, pointing out to their improved performance. Other systems underwent a partial upgrade, mainly by having their VME-based ADCs replaced with MTCA type. The overall status of the diagnostic will be reviewed.
	Slides MOOB03 [2.728 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOOB03
About •	paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOC03	The Removal of Interference Noise of ICT using the PCA Method	FEL, SRF, experiment, Windows	22
	J. Chen, Y.B. Leng, L.Y. Yu SINAP, Shanghai, People’s Republic of China N. Zhang SSRF, Shanghai, People’s Republic of China
	The measurement of beam charge is a fundamental re-quirement to all particle accelerators facility. Shanghai soft X-ray free-electron laser (SXFEL) started construc-tion in 2015 and is now in the commission phase. Al-though integrated current transformer (ICT) were installed in the entire FEL for the measurement of the absolute beam charge, the accurate measurement becomes difficult in the injector and the main accelerator section due to the noise interference from external factors such as klystron modulator. The evaluation of the source of noise signals and the procession of noise reduction using the principal component analysis (PCA) are proposed in this paper. Experiment results show that PCA method can effectively remove the interference of lower frequency noise from the klystron modulator and it can also improve the resolution of the ICT system. Detailed experiment results and data analysis will be mentioned as well.
	Slides MOOC03 [2.520 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOOC03
About •	paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPA07	Beam Diagnostics and Instrumentation for Proton Irradiation Facility at INR RAS Linac	diagnostics, radiation, linac, proton	40
	S.A. Gavrilov, A.A. Melnikov, A.I. Titov RAS/INR, Moscow, Russia
	The new proton irradiation facility to study radiation effects in electronics and other materials has been built in INR RAS linac. The range of the specified intensity from 10⁷ to 10¹² protons per beam pulse is covered with three beam diagnostic instruments: current transformer, phosphor screen and multianode gas counter. The peculiarities of the joint use of the three instruments are described. The experimental results of beam parameters observations and adjustments are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA07
About •	paper received ※ 04 September 2018 paper accepted ※ 14 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPA09	Overview of Beam Instrumentation and Commissioning Results from the Coherent Electron Cooling Experiment at BNL	cathode, laser, optics, undulator	43
	T.A. Miller, J.C.B. Brutus, W.C. Dawson, D.M. Gassner, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, D. Kayran, V. Litvinenko, C. Liu, R.J. Michnoff, M.G. Minty, P. Oddo, M.C. Paniccia, I. Pinayev, Z. Sorrell, J.E. Tuozzolo BNL, Upton, Long Island, New York, USA V. Litvinenko Stony Brook University, Stony Brook, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy The Coherent Electron Cooling (CeC) Proof-of-Principle experiment [1], installed in the RHIC tunnel at BNL, has completed its second run. In this experiment, an FEL is used to amplify patterns imprinted on the cooling electron beam by the RHIC ion bunches and then the imprinted pattern is fed back to the ions to achieve cooling of the ion beam. Diagnostics for the CeC experiment have been fully commissioned during this year’s run. An overview of the beam instrumentation is presented, this includes devices for measurements of beam current, position, profile, bunch charge, emittance, as well as gun photocathode imaging and FEL infra-red light emission diagnostics. Design details are discussed and beam measurement results are presented. [1] I. Pinayev, et al, ’First Results of Proof-of-Principle Experiment of Coherent Electron Cooling at BNL’ proceedings from IPAC 2018, Vancouver, CANADA
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA09
About •	paper received ※ 04 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPA14	Electron Spectrometer for a Low Charge Intermediate Energy LWFA Electron Beam Measurement	dipole, experiment, laser, vacuum	57
	A.V. Ottmar, Yu.I. Maltseva, T.V. Rybitskaya BINP SB RAS, Novosibirsk, Russia V. Gubin Institute of Laser Physics, SB RAS, Novosibirsk, Russia
	The Laser-driven Compton light source is under development in ILP SB RAS in collaboration with BINP SB RAS. Electron spectrometer for measurement of LWFA electron beam with energy in the range 10-150 MeV and bunch charge 1-10 pC is presented. Spectrometer based on permanent magnet and luminous screen with CCD registrar and this geometry was optimized for best measurements resolution in compromise with size limitations. Preliminary collimation of electron beam allows achieving energy resolution up to 5-10 % of top limit. System has been tested at the VEPP-5 linear electron accelerator and obtained results correspond to design objectives. Sensitivity of beam transverse charge density was experimentally fixed at 0.03 pC/mm², it is practically sufficient for our LWFA experiments.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA14
About •	paper received ※ 03 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPA16	Design of a Compact Permanent Magnet Spectrometer for CILEX/APOLLON	permanent-magnet, dipole, laser, induction	61
	M. Khojoyan, A. Cauchois, J. Prudent, A. Specka LLR, Palaiseau, France
	Laser wakefield acceleration experiments make extensive use of small permanent magnets or magnet assemblies for analyzing and focusing electron beams produced in plasma accelerators. This choice is motivated by the ease of operation inside vacuum chambers, absence of power-supplies and feedthroughs, and potentially lower cost. Indeed, in these experiments space is at premium, and compactness is frequently required. At the same time, these magnets have to have a large angular acceptance for the divergent laser and electron beams which imposes constraint of the gap size. We will present the optimized design and characterization of a 100 mm long, 2.1 Tesla permanent magnet dipole. Furthermore, we will present the implementation of this magnet in a spectrometer that will measure the energy spectrum of electrons of [60-2000] MeV with a few percent resolution in the CILEX/APOLLON 10PW laser facility in France.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA16
About •	paper received ※ 03 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPA17	Momentum Compaction Measurement Using Synchrotron Radiation	SRF, radiation, photon, experiment	66
	L. Torino, N. Carmignani, A. Franchi ESRF, Grenoble, France
	The momentum compaction factor of a storage ring can be obtained by measuring how the beam energy changes with the RF frequency. Direct measurement of the beam energy can be difficult, long or even not possible with acceptable accuracy and precision in some machines such as ESRF. Since the energy spectrum of the Synchrotron Radiation (SR) depends on the beam energy, it is indeed possible to relate the variation of the beam energy with a variation of the produced SR flux. In this proceeding, we will present how we obtain a measurement of the momentum compaction using this dependence.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA17
About •	paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPB02	ARIES-ADA: An R&D Network for Advanced Diagnostics at Accelerators	synchrotron, diagnostics, emittance, hadron	71
	P. Forck, M. Sapinski GSI, Darmstadt, Germany C. Gerth, K. Wittenburg DESY, Hamburg, Germany U. Iriso, F. Pérez ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain R. Ischebeck PSI, Villigen PSI, Switzerland O.R. Jones CERN, Meyrin, Switzerland
	Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under Grant Agreement No 730871. Accelerator Research and Innovation for European Science and Society, ARIES, is an initiative funded by the European Union (https://aries.web.cern.ch/). The activity comprises three major categories: Joint Research Activities; Transnational Access; Network Activities. One of these networks is related to Advanced Diagnostics at Accelerators (ADA) with the task of strengthening collaborations between international laboratories for coordinated research and development in beam diagnostics (https://aries.web.cern.ch/content/wp8). This task is performed by organizing topical workshops on actual developments and supporting interchange of experts between different labs. Since the start of the project in May 2017 four topical workshops of two to three days duration have been organized, each with 30-40 participants ranging from novices to worldwide experts in their particular field. In this contribution these initial workshops are summarized and an outlook given for further workshops within this ARIES-ADA network.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB02
About •	paper received ※ 03 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPB04	Progress in the Stripline Kicker for ELBE	kicker, simulation, laser, neutron	78
	Ch. Schneider, A. Arnold, J. Hauser, P. Michel HZDR, Dresden, Germany
	The linac based cw electron accelerator ELBE operates different secondary beamlines one at a time. For the future different end stations should be served simultaneously, hence specific bunch patterns have to be kicked into different beam-lines. The variability of the bunch pattern and the frequency resp. switching time are one of the main arguments for a stripline-kicker. A design with two tapered active electrodes and two ground fenders was optimized in time and frequency domain with the software package CST. From that a design has been transferred into a construction and was manufactured. The presentation summarises the recent results and the status of the project.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB04
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPB10	A Study on the Influence of Bunch Longitudinal Distribution on the Cavity Bunch Length Measurement	cavity, FEL, quadrupole, flattop	97
	Q. Wang, Q. Luo, B.G. Sun, F.F. Wu USTC/NSRL, Hefei, Anhui, People’s Republic of China
	Funding: Supported by National Key R&D Program of China (2016YFA0401900, 2016YFA0401903), NSFC (11375178, 11575181) and the Fundamental Research Funds for the Central Universities (WK2310000046) Cavity bunch length measurement is used to obtain the bunch length depending on the eigenmodes exciting in-side the cavity. For today’s FELs, the longitudinal distribution of particles in electron bunch (bunch shape) may be non-Gaussian, sometimes very novel. In this paper, the influence of bunch shape on the cavity bunch length measurement is analyzed, and some examples are given to verify the theoretical results. The analysis shows that the longitudinal distribution of particles in electron bunch has little influence on the cavity bunch length measure-ment when the bunch length is less than 1 ps and the eigenmodes used in measurement are below 10GHz.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB10
About •	paper received ※ 09 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPB13	Active Magnetic Field Compensation System for SRF Cavities	cavity, SRF, controls, electronics	101
	L.H. Ding Laboratory GREYC, Caen, France J. Liang, H. Liu, Z.P. Xie Hohai University, Nanjing, People’s Republic of China Z.P. Xie IMP/CAS, Lanzhou, People’s Republic of China
	Abstract: Superconducting Radio Frequency (SRF) cavities are becoming popular in modern particle accelerators. When the SRF cavity is transitioning from the non-conducting to the Superconducting state at the critical temperature (Tc), the ambient magnetic field can be trapped. This trapped flux may lead to an increase in the surface resistance of the cavity wall, which can reduce the Q-factor and efficiency of the cavity. In order to increase the Q-factor, it is important to lower the surface resistance by reducing the amount of magnetic flux trapped in the cavity wall to sub 10mG range during the Tc transition. In this paper, we present a 3-axis automatic active magnetic field compensation system that is capable of reducing the earth magnetic field and any local disturbance field. Design techniques are described to enhance the system stability while utilizing the flexibility of embedded electronics. This paper describes the system implementation and concludes with initial results of tests. Experimental results demonstrate that the proposed magnetic field compensation system can reduce the earth magnetic field to around 2.5 mG even without shielding.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB13
About •	paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPB17	Using a TE011 Cavity as a Magnetic Momentum Monitor	cavity, GUI, impedance, coupling	111
	J. Guo, J. Henry, M. Poelker, R.A. Rimmer, R. Suleiman, H. Wang JLab, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC with Laboratory Directed Research and Development funding, under U.S. DOE Contract No. DE-AC05-06OR23177. The Jefferson Lab Electron-Ion Collider (JLEIC) design relies on cooling of the ion beam with bunched electron beam constrained in a pair of long solenoids. The high current cooling electron beam needs to be generated in a magnetized electron source, and the beam’s magnetization needs to be maintained during the acceleration and transport to the cooling channel. A non-invasive real time monitoring system is highly desired to quantify electron beam magnetization. The authors propose to use a passive copper RF cavity in TE011 mode as such a monitor. In this paper, we present the mechanism and scaling law of this device, as well as the design and preliminary test results of the prototype cavity.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB17
About •	paper received ※ 11 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPC02	Identification of Faulty Beam Position Monitor Based Clustering by Fast Search and Find of Density Peaks	SRF, storage-ring, electronics, operation	114
	R. Jiang, Y.B. Leng SSRF, Shanghai, People’s Republic of China F.Z. Chen, Z.C. Chen, Y.B. Leng SINAP, Shanghai, People’s Republic of China
	The accuracy and stability of beam position moni-tors(BPMs) are important for all kinds of measurement systems and feedback systems in particle accelerator field. A proper method detecting faulty beam position monitor or monitoring their stability could optimize accel-erator operating conditions. With development in ma-chine learning methods, a series of powerful analysis approaches make it possible for detecting beam position monitor’s stability. Here, this paper proposed a clustering analysis approach to detect the defective BPMs. The method is based on the idea that cluster centres are char-acterized by a higher density than their neighbours and by a relatively large distance from points with higher densi-ties. The results showed that clustering by fast search and find of density peaks could classify beam data into dif-ferent clusters on the basis of their similarity. And that, aberrant data points could be detected by decision graph. So the algorithm is appropriate for BPM detecting and it could be a significant supplement for data analysis in accelerator physics.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPC02
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPC03	Precise Measurement of Small Currents at the MLS	radiation, experiment, storage-ring, synchrotron	118
	Y. Petenev, J. Feikes, J. Li, A.N. Matveenko, Y. Tamashevich HZB, Berlin, Germany R. Klein, J. Lubeck, R. Thornagel PTB, Berlin, Germany
	The Physikalisch-Technische Bundesanstalt (PTB), the National Metrology Institute of Germany, utilizes an electron storage ring - the Metrology Light Source (MLS), located in Berlin, as a radiation source standard in the VIS, UV and VUV spectral range. In order to be able to calculate the absolute intensity of the radiation, the electron beam current has to be measured with low uncertainty. In this paper we focus on the measurement of the beam current in a range of several nA to 1 pA (one electron) by means of Si photodiodes, detecting synchrotron radiation from the beam. Electrons are gradually scraped out of the ring and the diode signal is analyzed afterwards. The exact number of stored electrons then can be derived from the signal. The measurement is carried out automatically with an in-house developed software.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPC03
About •	paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPC10	Upgrade and Improvement of CT Based on TMR	electronics, simulation, vacuum, power-supply	134
	Y. Zhao, Y.Y. Du, L. Wang IHEP, Beijing, People’s Republic of China
	The CT based on TMR sensor has been developed in the lab. For Improving the accuracy and linearity, re-ducing the influence of sensor position, a series simu-lation and calculation have been done which conduct an upgrade both in the mechanical structure and elec-tronics design. Lab test shows good results and test on beam will be carried on soon.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPC10
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOA01	The Diagnostic System at the European XFEL; Commissioning and First User Operation	FEL, MMI, diagnostics, operation	162
	D. Nölle DESY, Hamburg, Germany
	The European XFEL is now commissioned and user operation has started. Long bunch trains up to 300 bunches are established. The role of and experience with the beam diagnostic will be reported. Highlights, problems and their solutions will be discussed.
	Slides TUOA01 [8.932 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOA01
About •	paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOB04	A Vertical Phase Space Beam Position and Emittance Monitor for Synchrotron Radiation	synchrotron, experiment, detector, photon	186
	N. Samadi University of Saskatchewan, Saskatoon, Canada L.D. Chapman, L.O. Dallin CLS, Saskatoon, Saskatchewan, Canada
	We report on a system (ps-BPM) that can measure the electron source position and angular motion at a single location in a synchrotron bend magnet beamline using a combination of a monochromator and an absorber with a K-edge to which the monochromator was tuned in energy. The vertical distribution of the beam was visualized with an imaging detector where horizontally one part of the beam was with the absorber and the other part with no absorber. The small range of angles from the source onto the monochromator crystals creates an energy range that allows part of the beam to be below the K-edge and the other part above. Measurement of the beam vertical location without the absorber and edge vertical location with the absorber gives the source position and angle. Measurements were made to investigate the possibility of using the ps-BPM to correct experimental imaging data. We have introduced periodic electron beam motion using a correction coil in the storage ring lattice. The measured and predicted motions compared well for two different frequencies. We then show that measurement of the beam width and edge width gives information about the vertical electron source size and angular distribution. [1] A phase-space beam position monitor for synchrotron radiation. J Synchrotron Radiat, 2015. 22(4): p. 946-55.
	Slides TUOB04 [9.532 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOB04
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOC01	Integration of a Pilot-Tone Based BPM System Within the Global Orbit Feedback Environment of Elettra	FPGA, controls, feedback, Ethernet	190
	G. Brajnik, S. Bassanese, G. Cautero, S. Cleva, R. De Monte Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
	In this contribution, we describe the advantages of the pilot tone compensation technique that we implemented in a new BPM prototype for Elettra 2.0. Injecting a fixed reference tone upstream of cables allows for a continuous calibration of the system, compensating the different behaviour of every channel due to thermal drifts, variations of cable properties, mismatches and tolerances of components. The system ran successfully as a drop-in substitute for a Libera Electron not only during various machine shifts, but also during a user dedicated beamtime shift for more than 10 hours, behaving in a transparent way for all the control systems and users. The equivalent RMS noise (at 10 kHz data rate) for the pilot tone position was less than 200 nm on a 19 mm vacuum chamber radius, with a long-term stability better than 1 um in a 12-hour window. Two main steps led to this important result: firstly, the development of a novel RF front end that adds the pilot tone to the signals originated by the beam, secondly, the realisation of an FPGA-based double digital receiver that demodulates both beam and pilot amplitudes, calculating the compensated X and Y positions.
	Slides TUOC01 [6.468 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOC01
About •	paper received ※ 31 August 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOC03	Commissioning of the Open Source Sirius BPM Electronics	electronics, controls, FPGA, timing	196
	S.R. Marques, G.B.M. Bruno, L.M. Russo, H.A. Silva, D.O. Tavares LNLS, Campinas, Brazil
	The new Brazilian 4th generation light source, Sirius, have already started and commissioning is planned to start in 2018. This paper will report on the manufacturing, deployment and production batch testing of the in-house developed BPM electronics. The latest performance and reliability achievements will be presented.
	Slides TUOC03 [14.606 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOC03
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOC04	Development of Beam Position Monitor for the SPring-8 Upgrade	electronics, radiation, storage-ring, brilliance	204
	H. Maesaka RIKEN SPring-8 Center, Innovative Light Sources Division, Hyogo, Japan H. Dewa, T. Fujita, M. Masaki, S. Takano JASRI, Hyogo, Japan
	We are developing a new electron beam position monitor (BPM) system for the low-emittance upgrade of SPring-8. The requirements for the BPM system are: (1) a single-pass resolution of 100 µm rms for a 100 pC bunch and an electric center accuracy of 100 µm rms for the initial beam commissioning to achieve the first turn, (2) a closed-orbit distortion (COD) resolution better than 0.1 µm rms for a 100 mA stored beam and a position stability of less than 5 µm for the ultimate stability of a photon beam axis. We have completed prototypes of a precise button electrode and a BPM block to obtain high-intensity signals and sufficient mechanical accuracy while suppressing high-Q trapped modes leading to impedance and heating issues. The development of readout electronics based on the MTCA.4 standard and the evaluation of radiation-hard coaxial cables have also been conducted. The prototype BPM head was installed in the present SPring-8 storage ring for performance verification with an actual electron beam. We confirmed sufficient signal intensity, electric center accuracy, position stability, etc. by the beam test. The new BPM system is almost ready for the SPring-8 upgrade.
	Slides TUOC04 [2.126 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOC04
About •	paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA03	Test of New Beam Loss Monitors for SOLEIL	storage-ring, detector, controls, shielding	215
	N. Hubert, M. El Ajjouri, D. Pédeau SOLEIL, Gif-sur-Yvette, France
	Soleil is currently testing new beam loss monitors to replace its pin-diode based existing system. The new detectors are made of plastic scintillators associated with photomultiplier and connected to Libera BLM dedicated electronics. This new detector should provide both fast (turn by turn) and slow (averaged) loss measurements, post mortem capabilities and should be less sensitive to the beam directivity compared to the pin-diodes. Different methods for a relative calibration of the modules are under investigation, either using a diode (LED) or a cesium radioactive source. Calibration results and first measurements with beam are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPA03
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA08	Arc Discharge Detectors for the CiADS Superconducting RF Cavities	detector, hardware, software, cavity	228
	Z.P. Xie, Y.K. Ding, J. Liang, H. Liu Hohai University, Nanjing, People’s Republic of China Y. He, Y.M. Li IMP/CAS, Lanzhou, People’s Republic of China
	Funding: Work supported by the National Natural Science Foundation of China (Grant No.11505255, No.91026001) and the Fundamental Research Funds for the Chinese Central Universities(2015B29714) Arc discharge due to the electron emission is one of the key issues in the CW superconducting RF(SRF) for the CiADS particle accelerator. Arc discharges can deteriorate the SRF cavities and damage the facility. Monitoring arc discharges is important for the purpose of machine protection. In this paper, an arc discharge detector has been designed to provide fast response upon events of arc discharge using open-source hardware and LabVIEW software. Electronic design techniques are described to enhance the system stability while utilizing the flexibility of embedded electronics. The proposed detector system gives about 700 ns of response time and it employs a LabVIEW based graphic user interface. The system has the capability of detecting the instantaneous arc discharge events in real time. Timestamps of the event will be recorded to assist beam diagnostics. This paper describes the hardware/software implementation and concludes with initial results of tests at CiADS.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPA08
About •	paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA17	Status of the BNL LEReC Machine Protection System	gun, MMI, laser, operation	249
	S. Seletskiy, Z. Altinbas, D. Bruno, M.R. Costanzo, K.A. Drees, A.V. Fedotov, D.M. Gassner, X. Gu, L.R. Hammons, J. Hock, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, D. Kayran, J. Kewisch, C. Liu, K. Mernick, T.A. Miller, M.G. Minty, M.C. Paniccia, W.E. Pekrul, I. Pinayev, V. Ptitsyn, V. Schoefer, L. Smart, K.S. Smith, R. Than, P. Thieberger, J.E. Tuozzolo, W. Xu, Z. Zhao BNL, Upton, Long Island, New York, USA
	The low energy RHIC Electron Cooler (LEReC) will be operating with 1.6-2.6 MeV electron beams having up to 140 kW power. It was determined that under the worst case scenario the missteered electron beam can damage the vacuum chamber and in-vacuum components within 40 us. Hence, the LEReC requires a dedicated fast machine protection system (MPS). The LEReC MPS has been designed and built and currently is under commissioning. In this paper we describe the most recent developments with the LEReC MPS.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPA17
About •	paper received ※ 31 August 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB01	The Installation and Commissioning of the AWAKE Stripline BPM	electronics, proton, MMI, TRIUMF	253
	S. Liu, P.E. Dirksen, V.A. Verzilov TRIUMF, Vancouver, Canada S.J. Gessner, F. Guillot-Vignot, D. Medina, L. Søby CERN, Geneva, Switzerland
	Funding: # TRIUMF contribution was supported by NSERC and CNRC AWAKE (The Advanced Proton Driven Plasma Wakefield Acceleration Experiment at CERN) stripline BPMs are required to measure the position of the single electron bunch to a position resolution of less than 10 µm rms for electron charge of 100 pC to 1 nC. This paper describes the design, installation and commissioning of a such BPM system developed by TRIUMF (Canada). Total 12 BPMs and electronics had been installed on AWAKE beam lines and started commissioning since Fall of 2017. The calibration and measurement performance are also reviewed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB01
About •	paper received ※ 04 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB02	Complete Test Results of New BPM Electronics for the ESRF New LE-Ring	electronics, SRF, controls, MMI	257
	K.B. Scheidt ESRF, Grenoble, France
	Among the 320 BPMs in the ESRF new low emittance ring, a set of 128 units will be equipped with new electronics, while the other set (192) will be served by the existing Libera-Brilliance electronics. These new electronics are an upgraded version of the low-cost Spark electronics originally developed 3 years ago for the ESRF Injector complex. All these 128 units have been installed in the first half of 2018 on existing BPM signals (through duplication with RF-splitters) and subsequently been tested thoroughly for performance characteristics like stability, resolution and reliability. It will be shown that while these Sparks have a very straightforward and simple concept, i.e. completely omitting calibration schemes like RF-cross-bar switching, pilot-tone introduction or active temperature control, that they are fully compatible with all the beam position measurement requirements of this new ring.
	Poster TUPB02 [1.577 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB02
About •	paper received ※ 30 August 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB03	Results of SPIRAL2 Beam Position Monitors on the Test Bench of the RFQ	linac, operation, rfq, electronics	261
	M. Ben Abdillah, P. Ausset IPN, Orsay, France R. Ferdinand GANIL, Caen, France
	SPIRAL2 project is based on a multi-beam superconducting LINAC designed to accelerate 5 mA deuteron beams up to 40 MeV, proton beams up to 33 MeV and 1 mA light and heavy ions (Q/A = 1/3) up to 14.5 MeV/A. The accurate tuning of the LINAC is essential for the operation of SPIRAL2 and requires measurement of the beam transverse position, the phase of the beam with respect to the radiofrequency voltage, the ellipticity of the beam and the beam energy with the help of Beam Position Monitor (BPM) system. The commissioning of the RFQ gave us the opportunity to install two BPM sensors, associated with their electronics, mounted on a test bench. The test bench is a D-plate fully equipped with a complete set of beam diagnostic equipment in order to characterize as completely as possible the beam delivered by the RFQ and to gain experience with the behavior of these diagnostics under beam operation. This paper addresses the measurements carried with the two BPMs on the Dplate: energy, transverse position and ellipticity under 750 KeV proton beam operation
	Poster TUPB03 [1.443 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB03
About •	paper received ※ 04 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB07	Stability Study of Beam Position Measurement Based on Higher Order Mode Signals at FLASH	HOM, cavity, dipole, higher-order-mode	273
	J.H. Wei USTC/NSRL, Hefei, Anhui, People’s Republic of China N. Baboi DESY, Hamburg, Germany L. Shi PSI, Villigen PSI, Switzerland
	FLASH is a free-electron laser driven by a supercon-ducting linac at DESY in Hamburg. It generates high-brilliance XUV and soft X-ray pulses by SASE (Self Amplified Spontaneous Emission). Many accelerating cavities are equipped with HOMBPMs (Higher Order Mode based Beam Position Monitors) to align the beam and monitor the transverse beam position. However, these lose their position prediction ability over time. In this paper, we applied an efficient measurement and signal analysis with various data process methods including PLS (Partial Least Square) and SVD (Singular Value Decomposition) to determine the transverse beam position. By fitting the HOM signals with a genetic algorithm, we implemented a new HOMBPM calibration procedure and obtained reliable beam prediction positions over a long time. A stable RMS error of about 0.2 mm by using the spectra of signals and 0.15 mm by using the new method over two months has been observed.
	Poster TUPB07 [1.816 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB07
About •	paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB09	The Evaluation of Beam Inclination Angle on the Cavity BPM Position Measurement	cavity, FEL, simulation, experiment	278
	J. Chen, L.W. Lai, Y.B. Leng, L.Y. Yu, R.X. Yuan SINAP, Shanghai, People’s Republic of China
	Cavity beam position monitor (CBPM) is widely used to measure the transverse position in free-electron laser (FEL) and international linear collider (ILC) facilities due to the characteristic of high sensitive. In order to study the limiting factors of the position resolution of cavity BPM, the influence of beam inclination angle on the measure-ment of CBPM position and the direction of beam deflec-tion was analyzed. The simulation results show that the beam inclination angle is an important factor limiting the superiority of CBPM with extremely high position resolu-tion. The relative beam experiments to change the relative inclination angle between the cavity and the electron beam based on a 4-dimension moveable platform were performed in Shanghai Soft X-ray FEL (SXFEL) facility, the experiment results will also be mentioned as well.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB09
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB10	Design and Simulation of Stripline BPM for HUST Proton Therapy Facility	coupling, impedance, proton, dipole	281
	J.Q. Li, Q.S. Chen, K. Fan, K. Tang, P. Tian HUST, Wuhan, People’s Republic of China
	Proton beams used in Huazhong University of Science and Technology Proton Therapy Facility（HUST-PTF）have extreme low currents of the order of nanoampere，which is a great challenge to beam diagnostics due to low signal level. Conventional destructive beam diagnostic devices will affect the quality of the beam and cannot work online during the patient treatment, so a non-destructive stripline beam position monitor (BPM) is designed. This study will introduce some analysis and simulation results of the stripline BPM, such as the coupling between the electrodes, impedance matching, signal response, etc. We also discussed how to increase the output signal by geometry optimization.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB10
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB13	Stability Tests with Pilot-Tone Based Elettra BPM RF Front End and Libera Electronics	electronics, real-time, instrumentation, FPGA	289
	M. Cargnelutti, P. Leban, M. Žnidarčič I-Tech, Solkan, Slovenia S. Bassanese, G. Brajnik, S. Cleva, R. De Monte Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
	Long-term stability is one of the most important properties of the BPM readout system. Recent developments on pilot tone capable front end have been tested with an established BPM readout electronics. The goal was to demonstrate the effectiveness of the pilot tone compensation to varying external conditions. Simulated cable attenuation change and temperature variation of the readout electronics were confirmed to have no major effect to position data readout. The output signals from Elettra front end (carrier frequency and pilot tone frequency) were processed by a Libera Spark with the integrated standard front end which contains several filtering, attenuation and amplification stages. Tests were repeated with a modified instrument (optimized for pilot tone) to compare the long-term stability results. Findings show the pilot tone front end enables great features like self-diagnostics and cable-fault compensation as well as small improvement in the long-term stability. Measurement resolution is in range of 10 nanometers RMS in 5 Hz bandwidth.
	Poster TUPB13 [1.223 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB13
About •	paper received ※ 31 August 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB14	New Beam Position Monitors for the CERN LINAC3 to LEIR Ion Beam Transfer Line	linac, simulation, solenoid, vacuum	293
	L. Søby, G. Baud, M. Bozzolan, R. Scrivens CERN, Geneva, Switzerland
	The injection line into the CERN Low Energy Ion Ring (LEIR) has recently been equipped with nine, new, electrostatic Beam Position Monitors (BPMs) in order to measure and optimize the trajectory of the low intensity ion beams coming from LINAC3. In this paper, we describe the design of the BPM, the low noise charge amplifier mounted directly on the BPM, and the digital acquisition system. There is special emphasis on the first commissioning results where the measured beam positions were seen to be perturbed by EMI and charging of the BPM electrodes by secondary particles. The effect of mitigation measures, including repelling voltages on the electrodes and external magnetic fields, are also discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB14
About •	paper received ※ 03 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC01	Australian Synchrotron BPM Electronics Upgrade	brilliance, coupling, synchrotron, storage-ring	297
	Y.E. Tan, R.B. Hogan AS - ANSTO, Clayton, Australia
	The storage ring at the Australian Synchrotron (AS) was originally equipped with 98 Libera Electrons. In late 2017 all 98 of the BPM electronics has been upgraded to Libera Brilliance⁺ and the old Libera Electrons have been moved to the injection system. The transition process and results from commissioning the new system will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC01
About •	paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC03	Beam Quality Monitoring System in the HADES Experiment at GSI Using CVD Diamond Material	detector, monitoring, experiment, electronics	300
	A. Rost, T. Galatyuk TU Darmstadt, Darmstadt, Germany J. Adamczewski-Musch, S. Linev, J. Pietraszko, M. Traxler GSI, Darmstadt, Germany
	Funding: Work supported by the DFG through GRK 2128 and VH-NG-823. The beam quality monitoring of extracted beams from SIS18, transported to the HADES experiment, is of great importance to ensure high efficiency data recording. The main detector system used for this purpose is the Start-Veto system which consists of two diamond based sensors made of pcCVD and scCVD materials. Both sensors are equipped with a double-sided strip segmented metalization (300 µm width) which allows a precise position determination of the beam position. Those senors are able to deliver a time precision <100 ps and can handle rate capabilities up to 10⁷ particles/channel. The read-out of the sensors is based on the TRB3 system [1]. Precise FPGA-TDCs (264 channels, <10 ps RMS) are implemented inside FPGAs. The TRB3 system serves as data acquisition system with scaler capability. Analysis and on-line visualization will be performed in DABC [2]. Having the precise time measurement and a precise position information of the incoming beam ions one can monitor important beam parameters namely the beam intensity, its position during extraction and the beam time structure. In this contribution the general read-out concept will be introduced. [1] A. Neiser et al., TRB3: a 264 channel high precision TDC platform and its applications, 2013 JINST 8 C12043. [2] dabc.gsi.de, 30.05.2018
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC03
About •	paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC04	BPM System Upgrade at COSY	controls, EPICS, electronics, operation	303
	V. Kamerdzhiev, I. Bekman, C. Böhme, B. Lorentz, S. Merzliakov, P. Niedermayer, K. Reimers, M. Simon, M. Thelen FZJ, Jülich, Germany
	The beam position monitoring system of the Cooler Synchrotron (COSY) has been upgraded in 2017. The upgrade was driven by the requirement of the JEDI collaboration to significantly improve the orbit control and by the electronics approaching end-of-life. The entire signal processing chain has been replaced. The new low noise amplifiers, mounted directly on the BPM vacuum feedthroughs, were developed in-house and include adjustable gain in 80 dB rage and in-situ test and calibration capabilities. The signals are digitized and processed by means of commercial BPM signal processing units featuring embedded EPICS IOC. The decision path, technical details of the upgrade and performance of the new system are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC04
About •	paper received ※ 13 September 2018 paper accepted ※ 14 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC05	Influence of Sampling Rate and Passband on the Performance of Stripline BPM	experiment, simulation, FEL, data-acquisition	307
	T. Wu, S.S. Cao, F.Z. Chen, Y.B. Leng, Y.M. Zhou SSRF, Shanghai, People’s Republic of China J. Chen, L.W. Lai SINAP, Shanghai, People’s Republic of China
	It is obviously that the property of SBPM is influenced by data acquisition system, but how the procedure of data acquisition and processing takes effect is still room for enquiring into it. This paper will present some data simulation and experiment results to discuss the function between resolution and pass band, sampling rate or other influence factor. We hope that this paper would give some advice for building up data acquisition system of SBPM.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC05
About •	paper received ※ 05 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC07	First Results of Button BPMs at FRIB	electronics, linac, MMI, pick-up	311
	S. Cogan, J.L. Crisp, T.M. Ford, S.M. Lidia FRIB, East Lansing, USA
	Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661, the State of Michigan and Michigan State University. Commissioning and tuning the linac driver for the Facility for Rare Isotope Beams (FRIB) requires a large network of warm and cryogenic BPMs, with apertures of 40 - 150 mm, sensitivity to beam currents of 100 nA to 1 mA, and accurate for beams with velocities as low as 0.03c. We present initial results of the BPM system, analog and digital signal processing, distortion and error correction, and calibration for time of flight (TOF) measurements. Measurements for low energy beams are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC07
About •	paper received ※ 13 September 2018 paper accepted ※ 20 November 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC09	Initial Results from the LHC Multi-Band Instability Monitor	detector, operation, synchrotron, betatron	314
	T.E. Levens, T. Lefèvre, D. Valuch CERN, Meyrin, Switzerland
	Intra-bunch transverse instabilities are routinely measured in the LHC using a "Head-Tail Monitor" based on sampling a wide-band BPM with a high-speed digitiser. However, these measurements are limited by the dynamic range and short record length possible with typical commercial oscilloscopes. This paper will present the initial results from the LHC Multi-Band Instability Monitor, a new technique developed to provide information on the beam stability with a high dynamic range using frequency domain analysis of the transverse beam spectrum.
	Poster TUPC09 [17.388 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC09
About •	paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC11	Design of an Ultrafast Stripline Kicker for Bunch-by-Bunch Feedback	kicker, FEL, impedance, HOM	322
	J. Wang, P. Li, D. Wu, D.X. Xiao, L.G. Yan CAEP/IAE, Mianyang, Sichuan, People’s Republic of China
	Funding: Work supported by China National Key Scientific Instrument and Equipment Development Project (2011YQ130018), National Natural Science Foundation of China (11475159, 11505173, 11575264 and 11605190) The CAEP THz Free Electron Laser (CTFEL) will have a fast transverse bunch-by-bunch feedback system on its test beamline, which is used to correct the beam position differences of individual bunches with interval of about 2 ns. In this paper, we are proposing an ultrafast wideband stripline kicker, which is able to provide a kick to the bunch in a 2 ns time window. The structure design and simulation results of this kicker are also discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC11
About •	paper received ※ 07 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC12	Beam Transverse Quadrupole Oscillation Measurement in the Injection Stage for the HLS-II Storage Ring	quadrupole, storage-ring, injection, betatron	325
	F.F. Wu, F.L. Gao, L.T. Huang, X.Y. Liu, P. Lu, B.G. Sun, J.G. Wang, J.H. Wei, T.Y. Zhou USTC/NSRL, Hefei, Anhui, People’s Republic of China
	Funding: Supported by the National Science Foundation of China (Grant No. 11705203, 11575181, 11605202) and the National Key Research and Development Program of China(No. 2016YFA0402000) Beam transverse quadrupole oscillation can be excited in the injection stage if injected beam parameters(twiss parameters or dispersion) are not matched with the parameters in the injection point of the storage ring. In order to measure the beam transverse quadrupole oscillation in the injection stage for the HLS-II storage ring, some axially symmetric stripline BPMs were designed. Transverse quadrupole component for these BPMs was simulated and off-line calibrated. Beam transverse quadrupole oscillation has been measured when beam was injected into the HLS-II electron storage ring. The spectrum of the transverse quadrupole component showed that beam transverse quadrupole oscillation is very obvious in the injection stage and this oscillation isn’t the second harmonic of beam betatron oscillation. The relationship between transverse quadrupole oscillation and beam current was also analyzed and the result shows that the relationship is not linear.
	Poster TUPC12 [0.467 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC12
About •	paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC13	Early Commissioning of the Luminosity Dither Feedback for SuperKEKB	luminosity, feedback, MMI, controls	328
	M. Masuzawa, Y. Funakoshi, T. Kawamoto, S. Nakamura, T. Oki, M. Tobiyama, S. Uehara KEK, Ibaraki, Japan P. Bambade, S. Di Carlo, D. Jehanno, C.G. Pang LAL, Orsay, France D.G. Brown, A.S. Fisher, M.K. Sullivan SLAC, Menlo Park, California, USA D. El Khechen CERN, Geneva, Switzerland U. Wienands ANL, Argonne, Illinois, USA
	SuperKEKB is an electron-positron collider, which aims to achieve a peak luminosity of 8×10³⁵ cm^-2 s⁻¹ using what is known as the "nano-beam" scheme. This paper reports on the commissioning and performance of a luminosity dither feedback. The system, based on one previously used at SLAC for PEP-II, is employed for collision orbit feedback in the horizontal plane. Twelve air-core Helmholtz coils drive the positron beam sinusoidally at a frequency near 80 Hz, forming a closed bump at the interaction point. A lock-in amplifier detects the amplitude and phase of the corresponding frequency component of the luminosity signal. When the beams are aligned for peak luminosity, the magnitude of the luminosity component at the dithering frequency becomes zero. The magnitude grows as the beams are offset, and the phase shifts by 180 degrees when the direction of the necessary correction reverses. The hardware and algorithm were tested during SuperKEKB Phase II run. The electron beam orbit was successfully adjusted to minimize the amplitude of the dither frequency component of the luminosity signal, and the optimal condition was maintained by continuously adjusting the electron beam orbit.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC13
About •	paper received ※ 09 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOA02	Optical Investigation to Minimize the Electron Bunch Arrival-time Jitter Between Femtosecond Laser Pulses and Electron Bunches for Laser-Driven Plasma Wakefield Accelerators	laser, plasma, ECR, polarization	332
	S. Mattiello, A. Penirschke THM, Friedberg, Germany H. Schlarb DESY, Hamburg, Germany
	Funding: The work of S. Mattiello is supported by the German Federal Ministry of Education and Research (BMBF) within the Project ’ MAKE-PWA. In a laser driven plasma based particle accelerators a stable synchronization of the electron bunch and of the plasma wakefield in the range of less than 2 fs is necessary in order to optimize the acceleration. For this purpose we are developing a new shot to shot feedback system with a time resolution of less than 1 fs. As a first step, stable THz pulses are generated by optical rectification of a fraction of the plasma generating high energy laser pulses in a nonlinear lithium niobate crystal. It is planed that the generated THz pulses will energy modulate the electron bunches shot to shot before the plasma to achieve the time resolution of 1 fs. In this contribution we systematically investigate the influence of the optical properties as well as the theoretical description of the THz generation on the conversion efficiency of the generation of short THz pulses in undepleted approximation. We compare different approximations for the modeling of the generation dynamics and of the dielectric function in order to investigate the importance of a detailed description of the optical properties. First results by considering intensity decreasing of the laser pump will be presented. *The feedback system will be tested at the Accelerator R&D facility SINBAD (Short Innovative Bunches and Accelerators at DESY).
	Slides WEOA02 [1.605 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOA02
About •	paper received ※ 04 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOA03	First Electro-Optical Bunch Length Measurements from the European XFEL	laser, FEL, optics, detector	338
	B. Steffen, M.K. Czwalinna, C. Gerth, P. Peier DESY, Hamburg, Germany
	Three electro-optical bunch length detection systems based on spectral decoding have been installed and are being commissioned at the European XFEL. The systems are capable of recording individual longitudinal bunch profiles with sub-picosecond resolution at a bunch repetition rate 1.13 MHz. Bunch lengths and arrival times of entire bunch trains with single-bunch resolution have been measured as well as jitter and drifts for consecutive bunch trains. In this paper, we present first measurement results for the electro-optical detection system located after the second bunch compressor. A preliminary comparison with data from the bunch arrival-time monitor shows good agreement.
	Slides WEOA03 [4.496 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOA03
About •	paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOA04	The Application of Beam Arrival Time Measurement at SXFEL	cavity, FEL, experiment, laser	342
	S.S. Cao, J. Chen, Y.B. Leng, R.X. Yuan SINAP, Shanghai, People’s Republic of China
	Shanghai soft X-ray free electron laser (SXFEL) is able to generate high brightness and ultra-short light pulses. The generation of the light sources relies on the synchronization between seeded laser and electron bunch. Beam arrival time play an important role to keep the synchronization. For the SXFEL, a beam arrival time resolution under 100 fs is required. In this paper, the application of beam arrival time measurement scheme on SXFEL has been presented. The whole BAM system consists of four parts: beam arrival time monitor, electronic front-end, signal acquisition system, and high-level signal processing and presentation. Currently, four sets of beam arrival time monitors (BAMs) have been installed in the SXFEL and distributed in four different locations. The relevant beam arrival time experiment and beam flight time experiment based on the dual-cavities mixing method have also been performed so as to evaluate and analyze the beam status.
	Slides WEOA04 [4.588 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOA04
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOB02	RadFET Dose Monitor System for SOLEIL	radiation, electronics, storage-ring, vacuum	353
	N. Hubert, F. Dohou, M. El Ajjouri, D. Pédeau SOLEIL, Gif-sur-Yvette, France
	Soleil is currently testing new dose monitors based on RadFET transistors. This new detector at SOLEIL will provide a measurement of the dose received by equipment that are damaged by the radiations in the storage ring, and to anticipate their replacement. This monitor should be very compact to be placed in tiny areas, sensitive to all kind of radiation and low cost to install many of them around the ring. A readout electronic module is being developed in-house, and a first prototype has been build and installed on the machine. Description of the system and first results recorded on the machine are presented.
	Slides WEOB02 [4.250 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOB02
About •	paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOB03	The European XFEL Beam Loss Monitor System	FEL, high-voltage, controls, undulator	357
	T. Wamsat, T. Lensch DESY, Hamburg, Germany
	The European XFEL MTCA based Beam Loss Monitor System (BLM) is composed of about 470 monitors, which are part of the Machine Protection System (MPS). The BLMs detect losses of the electron beam, in order to protect accelerator components from damage and excessive activation, in particular the undulators, since they are made of permanent magnets. Also each cold accelerating module is equipped with a BLM to measure the sudden onset of field emission (dark current) in cavities. In addition some BLMs are used as detectors for wire- scanners. Experience from the already running BLM system in FLASH2 which is developed for XFEL and tested here, led to a fast implementation of the system in the XFEL. Further firmware and server developments related to alarm generation and handling are ongoing. The BLM systems structure, the current status and the different possibilities to trigger alarms which stop the electron beam will be presented.
	Slides WEOB03 [3.631 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOB03
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOC02	Review of Recent Status of Coded Aperture X-ray Monitors for Beam Size Measurement	detector, optics, emittance, MMI	361
	J.W. Flanagan KEK, Ibaraki, Japan
	Funding: US-Japan Cooperation in High Energy Physics (Japan Monbukagakusho and US DOE). Kakenhi. X-ray beam profile monitors based on coded aperture imaging use an array of pinholes or slits to achieve large open apertures, which provide improved photon collection efficiency over single pinholes or slits. The resulting improvement in photon statistics makes possible single-bunch, single-turn measurements at lower bunch currents than are possible with a single pinhole or slit. In addition, the coded aperture pattern provides extra information for beam profile reconstruction, which makes possible somewhat improved resolution, as compared to a single slit. The reconstruction algorithm for coded aperture imaging is more complicated and computing-intensive than that for a single slit, though with certain classes of coded pertures a faster reconstruction method is possible. This talk will provide a survey of efforts to use coded aperture imaging for beam profile diagnostics at accelerators to date, covering principles and practical experiences with the technique, as well as prospects for the future at SuperKEKB, where it forms the primary means of measuring vertical beam sizes.
	Slides WEOC02 [4.065 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOC02
About •	paper received ※ 12 September 2018 paper accepted ※ 24 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOC03	A Simple Model to Describe Smoke Ring Shaped Beam Profile Measurements With Scintillating Screens at the European XFEL	FEL, diagnostics, scattering, ECR	366
	G. Kube, S. Liu, A.I. Novokshonov, M. Scholz DESY, Hamburg, Germany
	Standard beam profile measurements of high-brightness electron beams based on OTR may be hampered by coherence effects. Therefore it was decided for the European XFEL to measure transverse beam profiles based on scintillating screen monitors using LYSO:Ce. While it is possible to resolve beam sizes down to a few micrometers with this scintillator, the experience during the XFEL commissioning showed that the measured emittance values were significantly larger than the expected ones. In addition, beam profiles measured at bunch charges of a few hundred pC showed a ’smoke ring’ structure. While coherent OTR emission and beam dynamical influence can be excluded, it is assumed that the profile distortions are caused by effects from the scintillator material. Following the experience in high energy physics, a simple model was developed which takes into account quenching effects of excitonic carriers inside a scintillator in a heuristic way. Based on this model, the observed beam profiles can be understood qualitatively. Together with the model description, first comparisons with experiments will be presented, and new scintillators suitable for beam profile diagnostics will be discussed.
	Slides WEOC03 [2.411 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOC03
About •	paper received ※ 04 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOC04	Space Charge Effects Studies for the ESS Cold Linac Beam Profiler	space-charge, simulation, proton, HOM	371
	F. Belloni, P. Abbon, F. Benedetti, G. Coulloux, F. Gougnaud, C. Lahonde-Hamdoun, P. Le Bourlout, Y. Mariette, J. Marroncle, J.-Ph. Mols, V. Nadot, L. Scola CEA-DRF-IRFU, France C.A. Thomas ESS, Lund, Sweden
	Five Ionization Profile Monitors are being built by CEA in the framework of the in-kind contribution agreement signed with ESS. The IPMs will be installed in the Cold Linac where the proton energy range they need to cover extends from 90 MeV to 2 GeV. The ESS fields intensity of 1.10⁺⁰⁹ protons/bunch delivered at a frequency of 352 or 704 MHz, with a duty cycle of 4%, may strongly affect the trajectories of the ionized molecules and electrons created by the passage of the beam through the residual gas. In order to quantify and to develop a correction algorithm for these space charge effects, a code was initiated at ESS and completed at CEA Saclay with the possibility to include real case electric fields calculated with Comsol Multiphysics. A general overview of the code and its preliminary results are presented here.
	Slides WEOC04 [5.186 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOC04
About •	paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA09	Long Term Beam Phase Monitoring Based on HOM Signals in SC Cavities at FLASH	HOM, cavity, controls, FEL	388
	J.H. Wei USTC/NSRL, Hefei, Anhui, People’s Republic of China N. Baboi DESY, Hamburg, Germany L. Shi PSI, Villigen PSI, Switzerland
	The accelerating RF fields in superconducting cavities must be controlled precisely in FEL (Free Electron Laser) facilities to avoid beam energy spread and arrival time jitter. Otherwise the beam quality is degraded. The LLRF (Low Level Radio Frequency) system controls the RF field and provides a highly stable RF reference. A new type of beam phase determination technique based on beam-excited HOMs (Higher Order Modes) in cavities has been implemented. The two special couplers installed at both ends of each cavity, pick up the signals containing both the leakage of the accelerating field and the HOM signals. Therefore the signals can be used to calculate the beam phase directly with respect to the RF phase. We analysed the factors which may affect the result of the beam phase on a long-term based on an experimental platform at FLASH. Some phase drifts between the HOM-BPhM (Beam Phase Monitor) and the LLRF system phase measurement were observed and the reason will be further studied.
	Poster WEPA09 [1.720 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA09
About •	paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA12	Differential Evolution Genetic Algorithm for Beam Bunch Temporal Reconstruction	radiation, laser, FEL, experiment	392
	D. Wu, T.H. He, C.L. Lao, P. Li, J. Liu, X. Luo, Q. Pan, L.J. Shan, X. Shen, J. Wang, D.X. Xiao, L.G. Yan, P. Zhang, K. Zhou CAEP/IAE, Mianyang, Sichuan, People’s Republic of China Y. Liu CAEP/IFP, Mainyang, Sichuan, People’s Republic of China
	Funding: Work supported by China National Natural Science Foundation of China with grant (11475159, 11505173, 11505174, 11575264, 11605190 and 11105019) Coherent radiation, such as coherent transition radiation, coherent diffraction radiation, coherent synchrotron radiation, etc, can be used to measure the longitudinal distribution of the electron beam bunch of any length, as long as the coherent radiation spectrum can be measured. In many cases, the Kramers-Krönig relationship is used to reconstruct the temporal distribution of the beam from the coherent radiation spectrum. However, the extrapolation of the low frequency will introduce the uncertainty of the reconstruction. In this paper, an algorithm of differential evolution (DE) for temporal reconstruction is discussed. The DE reconstruction works well for the complex and ultrashort distribution. It will be an effectIve tool to accurately measure the femtosecond bunch temporal structure.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA12
About •	paper received ※ 07 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA13	Electro-Optic Modulator Based Beam Arrival Time Monitor for SXFEL	FEL, pick-up, timing, laser	396
	X.Q. Liu, L.F. Hua, L.W. Lai, Y.B. Leng, R.X. Yuan SINAP, Shanghai, People’s Republic of China N. Zhang SSRF, Shanghai, People’s Republic of China
	Beam arrival time monitor (BAM) is an important tool to investigate the temporal characteristic of elec-tron bunch in free electron laser (FEL) like Shanghai soft X-ray Free Electron Laser (SXFEL). Since the timing jitter of electron bunch will affect the FEL’s stability and the resolution of time-resolved experi-ment at FELs, it is necessary to precisely measure the electron bunch arrival time so as to reduce the timing jitter of the electron bunch with beam based feedback. The beam arrival time monitor based on electro-optic modulator (EOM) is already planned and will be de-veloped and tested at SXFEL in the next three years. Here the design and preliminary results of the EOM based beam arrival time monitor will be introduced in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA13
About •	paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA15	Development of BAM Electronics in PAL-XFEL	electronics, pick-up, controls, site	400
	D.C. Shin, J.H. Hong, H.-S. Kang, C. Kim, G. Kim, C.-K. Min PAL, Pohang, Republic of Korea
	We describe an electronics for electron bunch arrival time monitor (BAM) with a less than 10 femtosecond resolution, which was developed in 2017 and is currently in use at PAL-XFEL. When electron bunches go through an S-band monopole cavity, about 1 us long RF signal can be obtained to compare with a low phase noise RF reference. The differential phase jitter corresponds to the arrival time jitter of electron bunches. RF front-end (F/E) which converts the S-band pickup signal to intermediate frequency (IF) signal, is the essential part of a good time resolution. The digitizer and the signal processor of the BAM electronics are installed in an MTCA platform. This paper presents the design scheme, test results of the BAM electronics and future improvement plans.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA15
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA16	Micro-Bunching Instability Monitor for X-ray Free Electron Laser	radiation, bunching, laser, linac	404
	C. Kim, H.-S. Kang, G. Kim, I.S. Ko PAL, Pohang, Kyungbuk, Republic of Korea J.H. Ko POSTECH, Pohang, Kyungbuk, Republic of Korea
	A direct method was developed to measure the micro-bunching instability in the X-ray Free Electron Laser (XFEL). The micro-bunching instability comes from the interaction between the electron beam and the coherent synchrotron radiation (CSR), and the FEL intensity can be affected significantly by the micro-bunching instability. However, no effective method had been introduced to monitor the micro-bunching instability, so that we installed a CCD camera to measure the micro-bunching instability after the bunch compressor. The CCD camera showed the micro-bunching instability successfully, and more interesting features of the micro-bunching instability were revealed from it.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA16
About •	paper received ※ 09 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA17	Development, Fabrication and Laboratory Tests of Bunch Shape Monitors for ESS Linac	dipole, quadrupole, target, space-charge	407
	S.A. Gavrilov, D.A. Chermoshentsev, A. Feschenko RAS/INR, Moscow, Russia
	Two Bunch Shape Monitors have been developed and fabricated in INR RAS for European Spallation Source linac. To fulfil the requirements of a 4 ps phase resolution the symmetric λ-type RF-deflector based on the parallel wire line with capacitive plates has been selected. Additional steering magnet to correct incline of the focused electron beam is also used. Limitations due to space charge of the analysed beam and due to external magnetic fields are discussed. The results of the laboratory tests of the monitors are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA17
About •	paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA18	Development of Longitudinal Beam Profile Diagnostics for Beam-beam Effects Study at VEPP-2000	synchrotron, positron, collider, injection	410
	M.V. Timoshenko, V.M. Borin, O.I. Meshkov, Yu. A. Rogovsky, D.B. Shwartz, Yu.M. Zharinov BINP SB RAS, Novosibirsk, Russia V.L. Dorokhov BINP, Novosibirsk, Russia
	The comprehensive development of beam longitudinal profile measurement systems based on stroboscopic optical dissector has started at VEPP-2000 electron-positron collider complex. The dissector was setted and commissioned at booster ring BEP that was deeply upgraded (2013-2015) to achieve top energy of 1 GeV. Bunch lengthening with current was studied at BEP with its new RF-cavity. In addition the method of synchrotron frequency measurement by dissector was applied. After dissector checkouts at BEP the similar studies were carried out with a single beam at VEPP-2000 storage ring in parallel with streak-camera measurements. Good agreement of results was observed. Series of single-turn longitudinal and vertical bunch profiles snapshots was made by streak-camera with respect to delay after counter beam injection. The unexpected longitudinal beam dynamics was observed for intensities above the beam-beam threshold. These studies together with beam-beam coherent oscillations spectra seen by pickups are of a great interest for understanding of flip-flop phenomenon which establish a fundamental luminosity limit at VEPP-2000 operating with round beams.
	Poster WEPA18 [2.269 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA18
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA19	Results from the CERN LINAC4 Longitudinal Bunch Shape Monitor	linac, cavity, MMI, emittance	415
	J. Tan, G. Bellodi CERN, Geneva, Switzerland A. Feschenko, S.A. Gavrilov RAS/INR, Moscow, Russia
	The CERN Linac4 has been successfully commissioned to its nominal energy and will provide 160 MeV H⁻ ions for charge-exchange injection into the Proton Synchrotron Booster (PSB) from 2020. A complete set of beam diagnostic devices has been installed along the accelerating structures and the transfer line for safe and efficient operation. This includes two longitudinal Bunch Shape Monitors (BSM) developed by the Institute for Nuclear Research (INR, Moscow). Setting-up the RF cavities of Linac4 involves beam loading observations, time-of-flight measurements and reconstruction of the longitudinal emittance from phase profile measurements. In this paper the BSM is presented along with some results obtained during accelerator commissioning, including a comparison with phase measurements performed using the Beam Position Monitor system.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA19
About •	paper received ※ 07 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA20	First Results From the Bunch Arrival-Time Monitors at SwissFEL	laser, FEL, pick-up, MMI	420
	V.R. Arsov, P. Chevtsov, S. Hunziker, M.G. Kaiser, D. Llorente Sancho, A. Romann, V. Schlott, M. Stadler, D.M. Treyer PSI, Villigen PSI, Switzerland M. Dach Dach Consulting GmbH, Brugg, Switzerland
	Two Bunch Arrival-Time Monitors (BAM), based on fiber optical Mach-Zehnder intensity modulators, which encode the arrival-time information in the amplitude of the laser pulses delivered through a highly stable pulsed optical reference distribution system, have been commissioned and are operational at SwissFEL. The first BAM is at the RF-Gun, the second one is downstream the first bunch compressor. Both BAMs operate simultaneously and measure the arrival-time drift and jitter with less than 5 fs resolution. For the first time we have experimentally verified the excellent SwissFEL bunch stability. We have developed concepts and tested hardware, which enhance the commissioning and user operation. In particular we have successfully tested a tool for fast timing overlap between the electron bunch and the reference laser pulse, which allows fast system set-up and characterization. We have verified the capability for 2-bunch and 100 Hz operation. In comparison to the prototype detectors, which were operational at the SwissFEL test injector, we have achieved an improved BAM resolution in the range 10 pC - 200 pC.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA20
About •	paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB04	Comparison of YAG Screens and LYSO Screens at PITZ	HOM, emittance, laser, distributed	438
	R. Niemczyk, P. Boonpornprasert, Y. Chen, J.D. Good, M. Groß, H. Huck, I.I. Isaev, D.K. Kalantaryan, C. Koschitzki, M. Krasilnikov, X. Li, O. Lishilin, G. Loisch, D. Melkumyan, A. Oppelt, H.J. Qian, Y. Renier, F. Stephan, Q.T. Zhao DESY Zeuthen, Zeuthen, Germany W. Hillert University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
	The Photo Injector Test facility at DESY in Zeuthen (PITZ) is dedicated to the development of high-brightness electron sources for free-electron lasers. At PITZ, to measure the emittance of space-charge-dominated beams, the slit scan technique is used. For slice emittance measurements a transverse deflecting structure (TDS) is employed. The electron beam distribution is measured by means of scintillator screens. Both the TDS and the slit mask reduce the signal strength, giving stringent requirements on the sensitivity of the screens. At PITZ, high-sensitivity Ce:LYSO screens have been installed at the same screen stations as the standard Ce:YAG screens to solve low-intensity issues. A comparison of both screens is presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB04
About •	paper received ※ 03 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB09	Wire Scanner Measurements at the PAL-XFEL	undulator, FEL, emittance, controls	445
	G. Kim, H.-S. Kang, C. Kim, B.G. Oh, D.C. Shin PAL, Pohang, Kyungbuk, Republic of Korea
	The PAL-XFEL, an X-ray Free electron laser user facility based on a 10 GeV normal conducting linear accelerator, have been operational at Pohang, South Korea. The wire scanners are installed for transverse beam profile measurement of the Linac and the Hard X-ray undulator section. The wire scanner is a useful device for emittance measurements in the Hard X-ray undulator section. In this paper, we describe the details of the wire scanner and the results of the measurements.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB09
About •	paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB10	Grating Scanner for Measurement of Micron-size Beam Profiles	photon, simulation, positron, collider	448
	L.G. Sukhikh, A. Potylitsyn, S.A. Strokov TPU, Tomsk, Russia G. Kube, K. Wittenburg DESY, Hamburg, Germany
	Funding: The work was partly supported by the program ‘‘Nauka’ of the Russian Ministry of Education and Science, grant # 3.1903.2017 Wire scanners are widely used for transverse beam size diagnostics. The minimum detectable beam size is affected by the diameter of a single wire. The smallest carbon or tungsten wires used so far have diameters of about 4 microns. With the development of modern electron accelerators and the demands from future linear electron-positron colliders, sub-micron beam sizes have to be resolved. In order to increase the resolution, the decrease of the wire diameter is required. The authors of Ref. * proposed to manufacture thin gold stripes of rectangular shape (widths are equal to 1 µm or 2 µm and height is equal to 3 µm) on Si₃N₄ membrane. We propose to use another arrangement of gold stripes with varying period on a Si substrate. A set of 11 stripes with 1 µm width and 10 micron height with varying gap width in the range 3-0.25 µm ("grating scanner") was simulated by using an analytical model and by the Geant4 code. By moving this scanner across the beam one could measure the Bremsstrahlung yield vs. the coordinate, resulting in an oscillating dependence. The visibility of the resulting image allows defining the beam sizes in the range of 0.5-1.5 µm for the proposed scanner parameters. * S. Borrelli et al., "Generation and Measurement of Sub-Micrometer Relativistic Electron Beams", arXiv:1804.04252v1 [physics.acc-ph] 11 Apr 2018
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB10
About •	paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB11	Spatial Resolution Improvement of OTR Monitors by Off-axis Light Collection	radiation, target, diagnostics, photon	451
	A. Potylitsyn, A.I. Novokshonov, L.G. Sukhikh TPU, Tomsk, Russia G. Kube, A.I. Novokshonov DESY, Hamburg, Germany
	Funding: The work was partly supported by the program "Nauka" of the Russian Ministry of Education and Science, grant #3.1903.2017 The spatial resolution of an OTR monitor for electron beam profile diagnostics is determined by the resolution of the optical system and by the Point Spread Function (PSF) representing the single electron image. In the image plane, the PSF has a typical lobe-shape distribution with an inter-peak distance depending on wavelength and lens aperture ratio []. For a beam with a transverse rms size smaller than the distance, the reconstruction of the beam profile has several difficulties [, *]. We propose to reduce the PSF contribution and to improve the spatial resolution of an OTR monitor simply by rotating the lens optical axis with respect to the specular reflection direction. If the difference between the rotational angle and the lens aperture is much larger than the inverse Lorentz factor, the PSF has a Gaussian-like distribution which matches practically with the Airy distribution. Thus the resolution depends on wavelength and lens aperture. In principle, for lens apertures in the order of 0.1 rad such an approach should allow to measure beam sizes comparable to the wavelength of observation, using a simple deconvolution procedure for the measured image and the PSF. M. Castellano, V.Verzilov, Phys. Rev. ST-AB, 1 (1998). K.Kruchinin, S.T.Boogert, P.Karataev et al., Proc. IBIC 2013 (2013). * L.G. Sukhikh, A.P. Potylitsyn, G. Kube, Phys. Rev. AB 20 (2017).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB11
About •	paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB15	A Multipurpose Scintillating Fibre Beam Monitor for the Measurement of Secondary Beams at CERN	experiment, detector, electronics, secondary-beams	468
	I. Ortega Ruiz, L. Fosse, J. Franchi, A. Frassier, J. Fullerton, J. Kral, J. Lauener, T. Schneider, J. Spanggaard, G. Tranquille CERN, Meyrin, Switzerland
	A scintillating fibre beam monitor has been developed at CERN for the measurement of low energy and low intensity secondary beams. This monitor can track the passage of individual particles up to intensities of 10⁷ particles per second per mm², over an active area of 20 cm x 20 cm, and with a spatial resolution of 1 mm. Thanks to an external trigger system, the achieved detection efficiency is 95% and the noise level is kept below 10^-4 events/second. The simple design of this monitor avoids the common production difficulties of scintillating fibre detectors and makes its maintenance easier, when compared to other tracking detectors, due to the absence of gas or cooling. Using special electronics, a version of the monitor can also be used for time-of-flight measurements, achieving a time resolution of 900 ps. Thanks to its versatility, the monitor will perform several functions when measuring the secondary beams of the CERN Neutrino Platform: beam profile, position and intensity measurement, magnetic momentum spectrometry, particle identification through time-of-flight, and trigger generation for the experiments.
	Poster WEPB15 [1.172 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB15
About •	paper received ※ 03 September 2018 paper accepted ※ 14 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB16	Development of a Beam-Gas Curtain Profile Monitor for the High Luminosity Upgrade of the LHC	proton, simulation, vacuum, photon	472
	R. Veness, M. Ady, N. Chritin, J. Glutting, O.R. Jones, R. Kersevan, T. Marriott-Dodington, S. Mazzoni, A. Rossi, G. Schneider CERN, Meyrin, Switzerland P. Forck, S. Udrea GSI, Darmstadt, Germany A. Salehilashkajani The University of Liverpool, Liverpool, United Kingdom P. Smakulski WRUT, Wroclaw, Poland C.P. Welsch, H.D. Zhang Cockcroft Institute, Warrington, Cheshire, United Kingdom
	High luminosity upgrades to the LHC at CERN and future energy frontier machines will require a new generation of minimally invasive profile measurement instruments. Production of a dense, focussed gas target allows beam-gas fluorescence to be exploited as an observable, giving an instrument suitable for installation even in regions of high magnetic field. This paper describes the development of a device based on these principles that would be suitable for operation in the LHC. It focusses on mechanisms for the production of a homogeneous gas curtain, the selection of an appropriate working gas and the optical fluorescence detection system.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB16
About •	paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB18	Performance of a Reflective Microscope Objective in an X-ray Pinhole Camera	target, photon, emittance, storage-ring	477
	L. Bobb, G. Rehm DLS, Oxfordshire, United Kingdom
	X-ray pinhole cameras are used to measure the transverse beam profile of the electron beam in the storage ring from which the emittance is calculated. As improvements to the accelerator lattice reduce the beam emittance, e.g. with upgrades to fourth generation synchrotron light sources, likewise the beam size will be reduced such that micron and sub-micron scale resolution is required for beam size measurement. Therefore the spatial resolution of the pinhole camera imaging system must be improved accordingly. Here, the performance of a reflective microscope objective is compared to the high quality refractive lens which is currently in use to image the scintillator screen to the camera. The modulation transfer functions for each system have been assessed and will be discussed.
	Poster WEPB18 [0.751 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB18
About •	paper received ※ 04 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB20	Experimental Setup of Apodization Techniques for Beam Diagnostics Performed at ELBE	experiment, diagnostics, LabView, software	482
	B.G. Freeman, J. Gubeli, K. Jordan JLab, Newport News, Virginia, USA P.E. Evtushenko HZDR, Dresden, Germany
	The ELBE (Electron Linac for beams with high Brilliance and low Emittance) facility in Dresden, Germany is a multipurpose user facility, which is also used for accelerator R&D purposes. The beam line was set up for transverse beam profile measurements, where the imaging system includes a series of three apodizers and five circular apertures. During beam operations both of these were changed remotely through automated LabView routines. The bunch structure and charge were varied to collect a series of images that were acquired automatically, and then stored for later analysis. Over 12,000 images were captured and then analyzed using software written at Jefferson Lab that runs ImageJ as it’s main image processing library.
	Poster WEPB20 [0.357 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB20
About •	paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB21	Transverse Beam Emittance Measurements with Multi-Slit and Moving-Slit Devices for LEReC	emittance, cavity, optics, solenoid	486
	C. Liu, A.V. Fedotov, D.M. Gassner, X. Gu, D. Kayran, J. Kewisch, T.A. Miller, M.G. Minty, V. Ptitsyn, S. Seletskiy, A. Sukhanov, D. Weiss BNL, Upton, Long Island, New York, USA A. Fuchs Ward Melville High School, Setauket- East Setauket, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Low Energy RHIC electron cooling (LEReC) [1] is the first bunched electron cooler, designed to cool low energy ion beams at RHIC. The beam quality, including the transverse beam emittance, is critical for the success of cooling. The transverse electron beam emittance was characterized with a multi-slit and moving-slit device at various locations in the beamline. The beam emittance measurement and analysis are presented in this report.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB21
About •	paper received ※ 01 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPC04	Setup for Beam Profile Measurements using Optical Transition Radiation	target, radiation, linac, diagnostics	494
	J. Pforr, M. Arnold, T. Bahlo, L.E. Jürgensen, N. Pietralla, A. Rost TU Darmstadt, Darmstadt, Germany F. Hug KPH, Mainz, Germany
	Funding: Work supported by DFG through GRK 2128. The S-DALINAC is a thrice-recirculating, superconducting linear electron accelerator at TU Darmstadt. It can provide beams of electrons with energies up to 130 MeV and currents of 20 µA. The accelerator performance was improved by an extension of the beam diagnostics, as this increases the reproducibility of the machine settings. Therefore, the installation of several beam profile measurement stations is planned, which should be operational down to a beam current of 100 nA, as this current is used for beam tuning. Combining these devices with a quadrupole scan also allows for emittance measurements. The beam profile measurements shall be done based on optical transition radiation (OTR), resulting from the penetration of relativistic electrons from vacuum into a metal target. The radiation can be detected using standard cameras that provide information on the two-dimensional particle distribution. This contribution will address the layout of the measurement stations and a first test measurement will be presented.
	Poster WEPC04 [1.189 MB]

Paper

Title

Other Keywords

Page

MOOA02

Noise in Radio/Optical Communications

electronics, radio-frequency, optics, feedback

1

M. Vidmar
University of Ljubljana, Faculty of Electrical Engineering, Ljubljana, Slovenia

Noise is a random signal that affects the performance of all electronic and/or optical devices. Although the sources of different kinds of noise have their backgrounds in physics, engineers dealing with noise use different methods and units to specify noise. The intention of this tutorial is to describe the main effects of noise in electronics up to optical frequencies while providing links between the physics and engineering worlds. In particular, noise is considered harmful while degrading the signal-to-noise ratio or broadening the spectrum of signal sources. On the other hand, noise can be itself a useful signal. Finally, artificially generated signals that exhibit many properties of random natural noise are sometimes required.

Slides MOOA02 [3.742 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOOA02

About •

paper received ※ 28 August 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

MOOB03

Upgrade and Status of Standard Diagnostic-Systems at FLASH and FLASHForward

FEL, diagnostics, electronics, cavity

13

N. Baboi, H.T. Duhme, O. Hensler, G. Kube, T. Lensch, D. Lipka, B. Lorbeer, Re. Neumann, P.A. Smirnov, T. Wamsat, M. Werner
DESY, Hamburg, Germany

Electron beam diagnostics plays a crucial role in the precise and reliable generation of ultra-short high bril-liance XUV and soft X-ray beams at the Free Electron Laser in Hamburg (FLASH). Most diagnostic systems monitor each of up to typically 600 bunches per beam, with a frequency of up to 1 MHz, a typical charge be-tween 0.1 and 1 nC and an energy of 350 to 1250 MeV. The diagnostic monitors have recently undergone a major upgrade. This process started several years ago with the development of monitors fulfilling the requirements of the European XFEL and of the FLASH2 undulator beamline and it continued with their installation and commissioning. Later they have been further improved and an upgrade was made in the old part of the linac. Also the FLASHForward plasma-wakefield acceleration experiment has been installed in the third beamline. This paper will give an overview of the upgrade of the BPM, Toroid and BLM systems, pointing out to their improved performance. Other systems underwent a partial upgrade, mainly by having their VME-based ADCs replaced with MTCA type. The overall status of the diagnostic will be reviewed.

Slides MOOB03 [2.728 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOOB03

About •

paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

MOOC03

The Removal of Interference Noise of ICT using the PCA Method

FEL, SRF, experiment, Windows

22

J. Chen, Y.B. Leng, L.Y. Yu
SINAP, Shanghai, People’s Republic of China
N. Zhang
SSRF, Shanghai, People’s Republic of China

The measurement of beam charge is a fundamental re-quirement to all particle accelerators facility. Shanghai soft X-ray free-electron laser (SXFEL) started construc-tion in 2015 and is now in the commission phase. Al-though integrated current transformer (ICT) were installed in the entire FEL for the measurement of the absolute beam charge, the accurate measurement becomes difficult in the injector and the main accelerator section due to the noise interference from external factors such as klystron modulator. The evaluation of the source of noise signals and the procession of noise reduction using the principal component analysis (PCA) are proposed in this paper. Experiment results show that PCA method can effectively remove the interference of lower frequency noise from the klystron modulator and it can also improve the resolution of the ICT system. Detailed experiment results and data analysis will be mentioned as well.

Slides MOOC03 [2.520 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOOC03

About •

paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

MOPA07

Beam Diagnostics and Instrumentation for Proton Irradiation Facility at INR RAS Linac

diagnostics, radiation, linac, proton

40

S.A. Gavrilov, A.A. Melnikov, A.I. Titov
RAS/INR, Moscow, Russia

The new proton irradiation facility to study radiation effects in electronics and other materials has been built in INR RAS linac. The range of the specified intensity from 10⁷ to 10¹² protons per beam pulse is covered with three beam diagnostic instruments: current transformer, phosphor screen and multianode gas counter. The peculiarities of the joint use of the three instruments are described. The experimental results of beam parameters observations and adjustments are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA07

About •

paper received ※ 04 September 2018 paper accepted ※ 14 September 2018 issue date ※ 29 January 2019

Export •

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

MOPA09

Overview of Beam Instrumentation and Commissioning Results from the Coherent Electron Cooling Experiment at BNL

cathode, laser, optics, undulator

43

T.A. Miller, J.C.B. Brutus, W.C. Dawson, D.M. Gassner, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, D. Kayran, V. Litvinenko, C. Liu, R.J. Michnoff, M.G. Minty, P. Oddo, M.C. Paniccia, I. Pinayev, Z. Sorrell, J.E. Tuozzolo
BNL, Upton, Long Island, New York, USA
V. Litvinenko
Stony Brook University, Stony Brook, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy
The Coherent Electron Cooling (CeC) Proof-of-Principle experiment [1], installed in the RHIC tunnel at BNL, has completed its second run. In this experiment, an FEL is used to amplify patterns imprinted on the cooling electron beam by the RHIC ion bunches and then the imprinted pattern is fed back to the ions to achieve cooling of the ion beam. Diagnostics for the CeC experiment have been fully commissioned during this year’s run. An overview of the beam instrumentation is presented, this includes devices for measurements of beam current, position, profile, bunch charge, emittance, as well as gun photocathode imaging and FEL infra-red light emission diagnostics. Design details are discussed and beam measurement results are presented.
[1] I. Pinayev, et al, ’First Results of Proof-of-Principle Experiment of Coherent Electron Cooling at BNL’ proceedings from IPAC 2018, Vancouver, CANADA

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA09

About •

paper received ※ 04 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

MOPA14

Electron Spectrometer for a Low Charge Intermediate Energy LWFA Electron Beam Measurement

dipole, experiment, laser, vacuum

57

A.V. Ottmar, Yu.I. Maltseva, T.V. Rybitskaya
BINP SB RAS, Novosibirsk, Russia
V. Gubin
Institute of Laser Physics, SB RAS, Novosibirsk, Russia

The Laser-driven Compton light source is under development in ILP SB RAS in collaboration with BINP SB RAS. Electron spectrometer for measurement of LWFA electron beam with energy in the range 10-150 MeV and bunch charge 1-10 pC is presented. Spectrometer based on permanent magnet and luminous screen with CCD registrar and this geometry was optimized for best measurements resolution in compromise with size limitations. Preliminary collimation of electron beam allows achieving energy resolution up to 5-10 % of top limit. System has been tested at the VEPP-5 linear electron accelerator and obtained results correspond to design objectives. Sensitivity of beam transverse charge density was experimentally fixed at 0.03 pC/mm², it is practically sufficient for our LWFA experiments.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA14

About •

paper received ※ 03 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

MOPA16

Design of a Compact Permanent Magnet Spectrometer for CILEX/APOLLON

permanent-magnet, dipole, laser, induction

61

M. Khojoyan, A. Cauchois, J. Prudent, A. Specka
LLR, Palaiseau, France

Laser wakefield acceleration experiments make extensive use of small permanent magnets or magnet assemblies for analyzing and focusing electron beams produced in plasma accelerators. This choice is motivated by the ease of operation inside vacuum chambers, absence of power-supplies and feedthroughs, and potentially lower cost. Indeed, in these experiments space is at premium, and compactness is frequently required. At the same time, these magnets have to have a large angular acceptance for the divergent laser and electron beams which imposes constraint of the gap size. We will present the optimized design and characterization of a 100 mm long, 2.1 Tesla permanent magnet dipole. Furthermore, we will present the implementation of this magnet in a spectrometer that will measure the energy spectrum of electrons of [60-2000] MeV with a few percent resolution in the CILEX/APOLLON 10PW laser facility in France.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA16

About •

paper received ※ 03 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

MOPA17

Momentum Compaction Measurement Using Synchrotron Radiation

SRF, radiation, photon, experiment

66

L. Torino, N. Carmignani, A. Franchi
ESRF, Grenoble, France

The momentum compaction factor of a storage ring can be obtained by measuring how the beam energy changes with the RF frequency. Direct measurement of the beam energy can be difficult, long or even not possible with acceptable accuracy and precision in some machines such as ESRF. Since the energy spectrum of the Synchrotron Radiation (SR) depends on the beam energy, it is indeed possible to relate the variation of the beam energy with a variation of the produced SR flux. In this proceeding, we will present how we obtain a measurement of the momentum compaction using this dependence.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA17

About •

paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

MOPB02

ARIES-ADA: An R&D Network for Advanced Diagnostics at Accelerators

synchrotron, diagnostics, emittance, hadron

71

P. Forck, M. Sapinski
GSI, Darmstadt, Germany
C. Gerth, K. Wittenburg
DESY, Hamburg, Germany
U. Iriso, F. Pérez
ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
R. Ischebeck
PSI, Villigen PSI, Switzerland
O.R. Jones
CERN, Meyrin, Switzerland

Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under Grant Agreement No 730871.
Accelerator Research and Innovation for European Science and Society, ARIES, is an initiative funded by the European Union (https://aries.web.cern.ch/). The activity comprises three major categories: Joint Research Activities; Transnational Access; Network Activities. One of these networks is related to Advanced Diagnostics at Accelerators (ADA) with the task of strengthening collaborations between international laboratories for coordinated research and development in beam diagnostics (https://aries.web.cern.ch/content/wp8). This task is performed by organizing topical workshops on actual developments and supporting interchange of experts between different labs. Since the start of the project in May 2017 four topical workshops of two to three days duration have been organized, each with 30-40 participants ranging from novices to worldwide experts in their particular field. In this contribution these initial workshops are summarized and an outlook given for further workshops within this ARIES-ADA network.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB02

About •

paper received ※ 03 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

MOPB04

Progress in the Stripline Kicker for ELBE

kicker, simulation, laser, neutron

78

Ch. Schneider, A. Arnold, J. Hauser, P. Michel
HZDR, Dresden, Germany

The linac based cw electron accelerator ELBE operates different secondary beamlines one at a time. For the future different end stations should be served simultaneously, hence specific bunch patterns have to be kicked into different beam-lines. The variability of the bunch pattern and the frequency resp. switching time are one of the main arguments for a stripline-kicker. A design with two tapered active electrodes and two ground fenders was optimized in time and frequency domain with the software package CST. From that a design has been transferred into a construction and was manufactured. The presentation summarises the recent results and the status of the project.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB04

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

MOPB10

A Study on the Influence of Bunch Longitudinal Distribution on the Cavity Bunch Length Measurement

cavity, FEL, quadrupole, flattop

97

Q. Wang, Q. Luo, B.G. Sun, F.F. Wu
USTC/NSRL, Hefei, Anhui, People’s Republic of China

Funding: Supported by National Key R&D Program of China (2016YFA0401900, 2016YFA0401903), NSFC (11375178, 11575181) and the Fundamental Research Funds for the Central Universities (WK2310000046)
Cavity bunch length measurement is used to obtain the bunch length depending on the eigenmodes exciting in-side the cavity. For today’s FELs, the longitudinal distribution of particles in electron bunch (bunch shape) may be non-Gaussian, sometimes very novel. In this paper, the influence of bunch shape on the cavity bunch length measurement is analyzed, and some examples are given to verify the theoretical results. The analysis shows that the longitudinal distribution of particles in electron bunch has little influence on the cavity bunch length measure-ment when the bunch length is less than 1 ps and the eigenmodes used in measurement are below 10GHz.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB10

About •

paper received ※ 09 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019

Export •

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

MOPB13

Active Magnetic Field Compensation System for SRF Cavities

cavity, SRF, controls, electronics

101

L.H. Ding
Laboratory GREYC, Caen, France
J. Liang, H. Liu, Z.P. Xie
Hohai University, Nanjing, People’s Republic of China
Z.P. Xie
IMP/CAS, Lanzhou, People’s Republic of China

Abstract: Superconducting Radio Frequency (SRF) cavities are becoming popular in modern particle accelerators. When the SRF cavity is transitioning from the non-conducting to the Superconducting state at the critical temperature (Tc), the ambient magnetic field can be trapped. This trapped flux may lead to an increase in the surface resistance of the cavity wall, which can reduce the Q-factor and efficiency of the cavity. In order to increase the Q-factor, it is important to lower the surface resistance by reducing the amount of magnetic flux trapped in the cavity wall to sub 10mG range during the Tc transition. In this paper, we present a 3-axis automatic active magnetic field compensation system that is capable of reducing the earth magnetic field and any local disturbance field. Design techniques are described to enhance the system stability while utilizing the flexibility of embedded electronics. This paper describes the system implementation and concludes with initial results of tests. Experimental results demonstrate that the proposed magnetic field compensation system can reduce the earth magnetic field to around 2.5 mG even without shielding.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB13

About •

paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

MOPB17

Using a TE011 Cavity as a Magnetic Momentum Monitor

cavity, GUI, impedance, coupling

111

J. Guo, J. Henry, M. Poelker, R.A. Rimmer, R. Suleiman, H. Wang
JLab, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC with Laboratory Directed Research and Development funding, under U.S. DOE Contract No. DE-AC05-06OR23177.
The Jefferson Lab Electron-Ion Collider (JLEIC) design relies on cooling of the ion beam with bunched electron beam constrained in a pair of long solenoids. The high current cooling electron beam needs to be generated in a magnetized electron source, and the beam’s magnetization needs to be maintained during the acceleration and transport to the cooling channel. A non-invasive real time monitoring system is highly desired to quantify electron beam magnetization. The authors propose to use a passive copper RF cavity in TE011 mode as such a monitor. In this paper, we present the mechanism and scaling law of this device, as well as the design and preliminary test results of the prototype cavity.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB17

About •

paper received ※ 11 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

MOPC02

Identification of Faulty Beam Position Monitor Based Clustering by Fast Search and Find of Density Peaks

SRF, storage-ring, electronics, operation

114

R. Jiang, Y.B. Leng
SSRF, Shanghai, People’s Republic of China
F.Z. Chen, Z.C. Chen, Y.B. Leng
SINAP, Shanghai, People’s Republic of China

The accuracy and stability of beam position moni-tors(BPMs) are important for all kinds of measurement systems and feedback systems in particle accelerator field. A proper method detecting faulty beam position monitor or monitoring their stability could optimize accel-erator operating conditions. With development in ma-chine learning methods, a series of powerful analysis approaches make it possible for detecting beam position monitor’s stability. Here, this paper proposed a clustering analysis approach to detect the defective BPMs. The method is based on the idea that cluster centres are char-acterized by a higher density than their neighbours and by a relatively large distance from points with higher densi-ties. The results showed that clustering by fast search and find of density peaks could classify beam data into dif-ferent clusters on the basis of their similarity. And that, aberrant data points could be detected by decision graph. So the algorithm is appropriate for BPM detecting and it could be a significant supplement for data analysis in accelerator physics.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPC02

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

MOPC03

Precise Measurement of Small Currents at the MLS

radiation, experiment, storage-ring, synchrotron

118

Y. Petenev, J. Feikes, J. Li, A.N. Matveenko, Y. Tamashevich
HZB, Berlin, Germany
R. Klein, J. Lubeck, R. Thornagel
PTB, Berlin, Germany

The Physikalisch-Technische Bundesanstalt (PTB), the National Metrology Institute of Germany, utilizes an electron storage ring - the Metrology Light Source (MLS), located in Berlin, as a radiation source standard in the VIS, UV and VUV spectral range. In order to be able to calculate the absolute intensity of the radiation, the electron beam current has to be measured with low uncertainty. In this paper we focus on the measurement of the beam current in a range of several nA to 1 pA (one electron) by means of Si photodiodes, detecting synchrotron radiation from the beam. Electrons are gradually scraped out of the ring and the diode signal is analyzed afterwards. The exact number of stored electrons then can be derived from the signal. The measurement is carried out automatically with an in-house developed software.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPC03

About •

paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

MOPC10

Upgrade and Improvement of CT Based on TMR

electronics, simulation, vacuum, power-supply

134

Y. Zhao, Y.Y. Du, L. Wang
IHEP, Beijing, People’s Republic of China

The CT based on TMR sensor has been developed in the lab. For Improving the accuracy and linearity, re-ducing the influence of sensor position, a series simu-lation and calculation have been done which conduct an upgrade both in the mechanical structure and elec-tronics design. Lab test shows good results and test on beam will be carried on soon.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPC10

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

TUOA01

The Diagnostic System at the European XFEL; Commissioning and First User Operation

FEL, MMI, diagnostics, operation

162

D. Nölle
DESY, Hamburg, Germany

The European XFEL is now commissioned and user operation has started. Long bunch trains up to 300 bunches are established. The role of and experience with the beam diagnostic will be reported. Highlights, problems and their solutions will be discussed.

Slides TUOA01 [8.932 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOA01

About •

paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

TUOB04

A Vertical Phase Space Beam Position and Emittance Monitor for Synchrotron Radiation

synchrotron, experiment, detector, photon

186

N. Samadi
University of Saskatchewan, Saskatoon, Canada
L.D. Chapman, L.O. Dallin
CLS, Saskatoon, Saskatchewan, Canada

We report on a system (ps-BPM) that can measure the electron source position and angular motion at a single location in a synchrotron bend magnet beamline using a combination of a monochromator and an absorber with a K-edge to which the monochromator was tuned in energy. The vertical distribution of the beam was visualized with an imaging detector where horizontally one part of the beam was with the absorber and the other part with no absorber. The small range of angles from the source onto the monochromator crystals creates an energy range that allows part of the beam to be below the K-edge and the other part above. Measurement of the beam vertical location without the absorber and edge vertical location with the absorber gives the source position and angle. Measurements were made to investigate the possibility of using the ps-BPM to correct experimental imaging data. We have introduced periodic electron beam motion using a correction coil in the storage ring lattice. The measured and predicted motions compared well for two different frequencies. We then show that measurement of the beam width and edge width gives information about the vertical electron source size and angular distribution.
[1] A phase-space beam position monitor for synchrotron radiation. J Synchrotron Radiat, 2015. 22(4): p. 946-55.

Slides TUOB04 [9.532 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOB04

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

TUOC01

Integration of a Pilot-Tone Based BPM System Within the Global Orbit Feedback Environment of Elettra

FPGA, controls, feedback, Ethernet

190

G. Brajnik, S. Bassanese, G. Cautero, S. Cleva, R. De Monte
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

In this contribution, we describe the advantages of the pilot tone compensation technique that we implemented in a new BPM prototype for Elettra 2.0. Injecting a fixed reference tone upstream of cables allows for a continuous calibration of the system, compensating the different behaviour of every channel due to thermal drifts, variations of cable properties, mismatches and tolerances of components. The system ran successfully as a drop-in substitute for a Libera Electron not only during various machine shifts, but also during a user dedicated beamtime shift for more than 10 hours, behaving in a transparent way for all the control systems and users. The equivalent RMS noise (at 10 kHz data rate) for the pilot tone position was less than 200 nm on a 19 mm vacuum chamber radius, with a long-term stability better than 1 um in a 12-hour window. Two main steps led to this important result: firstly, the development of a novel RF front end that adds the pilot tone to the signals originated by the beam, secondly, the realisation of an FPGA-based double digital receiver that demodulates both beam and pilot amplitudes, calculating the compensated X and Y positions.

Slides TUOC01 [6.468 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOC01

About •

paper received ※ 31 August 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

TUOC03

Commissioning of the Open Source Sirius BPM Electronics

electronics, controls, FPGA, timing

196

S.R. Marques, G.B.M. Bruno, L.M. Russo, H.A. Silva, D.O. Tavares
LNLS, Campinas, Brazil

The new Brazilian 4th generation light source, Sirius, have already started and commissioning is planned to start in 2018. This paper will report on the manufacturing, deployment and production batch testing of the in-house developed BPM electronics. The latest performance and reliability achievements will be presented.

Slides TUOC03 [14.606 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOC03

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

TUOC04

Development of Beam Position Monitor for the SPring-8 Upgrade

electronics, radiation, storage-ring, brilliance

204

H. Maesaka
RIKEN SPring-8 Center, Innovative Light Sources Division, Hyogo, Japan
H. Dewa, T. Fujita, M. Masaki, S. Takano
JASRI, Hyogo, Japan

We are developing a new electron beam position monitor (BPM) system for the low-emittance upgrade of SPring-8. The requirements for the BPM system are: (1) a single-pass resolution of 100 µm rms for a 100 pC bunch and an electric center accuracy of 100 µm rms for the initial beam commissioning to achieve the first turn, (2) a closed-orbit distortion (COD) resolution better than 0.1 µm rms for a 100 mA stored beam and a position stability of less than 5 µm for the ultimate stability of a photon beam axis. We have completed prototypes of a precise button electrode and a BPM block to obtain high-intensity signals and sufficient mechanical accuracy while suppressing high-Q trapped modes leading to impedance and heating issues. The development of readout electronics based on the MTCA.4 standard and the evaluation of radiation-hard coaxial cables have also been conducted. The prototype BPM head was installed in the present SPring-8 storage ring for performance verification with an actual electron beam. We confirmed sufficient signal intensity, electric center accuracy, position stability, etc. by the beam test. The new BPM system is almost ready for the SPring-8 upgrade.

Slides TUOC04 [2.126 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOC04

About •

paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

TUPA03

Test of New Beam Loss Monitors for SOLEIL

storage-ring, detector, controls, shielding

215

N. Hubert, M. El Ajjouri, D. Pédeau
SOLEIL, Gif-sur-Yvette, France

Soleil is currently testing new beam loss monitors to replace its pin-diode based existing system. The new detectors are made of plastic scintillators associated with photomultiplier and connected to Libera BLM dedicated electronics. This new detector should provide both fast (turn by turn) and slow (averaged) loss measurements, post mortem capabilities and should be less sensitive to the beam directivity compared to the pin-diodes. Different methods for a relative calibration of the modules are under investigation, either using a diode (LED) or a cesium radioactive source. Calibration results and first measurements with beam are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPA03

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

TUPA08

Arc Discharge Detectors for the CiADS Superconducting RF Cavities

detector, hardware, software, cavity

228

Z.P. Xie, Y.K. Ding, J. Liang, H. Liu
Hohai University, Nanjing, People’s Republic of China
Y. He, Y.M. Li
IMP/CAS, Lanzhou, People’s Republic of China

Funding: Work supported by the National Natural Science Foundation of China (Grant No.11505255, No.91026001) and the Fundamental Research Funds for the Chinese Central Universities(2015B29714)
Arc discharge due to the electron emission is one of the key issues in the CW superconducting RF(SRF) for the CiADS particle accelerator. Arc discharges can deteriorate the SRF cavities and damage the facility. Monitoring arc discharges is important for the purpose of machine protection. In this paper, an arc discharge detector has been designed to provide fast response upon events of arc discharge using open-source hardware and LabVIEW software. Electronic design techniques are described to enhance the system stability while utilizing the flexibility of embedded electronics. The proposed detector system gives about 700 ns of response time and it employs a LabVIEW based graphic user interface. The system has the capability of detecting the instantaneous arc discharge events in real time. Timestamps of the event will be recorded to assist beam diagnostics. This paper describes the hardware/software implementation and concludes with initial results of tests at CiADS.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPA08

About •

paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

TUPA17

Status of the BNL LEReC Machine Protection System

gun, MMI, laser, operation

249

S. Seletskiy, Z. Altinbas, D. Bruno, M.R. Costanzo, K.A. Drees, A.V. Fedotov, D.M. Gassner, X. Gu, L.R. Hammons, J. Hock, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, D. Kayran, J. Kewisch, C. Liu, K. Mernick, T.A. Miller, M.G. Minty, M.C. Paniccia, W.E. Pekrul, I. Pinayev, V. Ptitsyn, V. Schoefer, L. Smart, K.S. Smith, R. Than, P. Thieberger, J.E. Tuozzolo, W. Xu, Z. Zhao
BNL, Upton, Long Island, New York, USA

The low energy RHIC Electron Cooler (LEReC) will be operating with 1.6-2.6 MeV electron beams having up to 140 kW power. It was determined that under the worst case scenario the missteered electron beam can damage the vacuum chamber and in-vacuum components within 40 us. Hence, the LEReC requires a dedicated fast machine protection system (MPS). The LEReC MPS has been designed and built and currently is under commissioning. In this paper we describe the most recent developments with the LEReC MPS.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPA17

About •

paper received ※ 31 August 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

TUPB01

The Installation and Commissioning of the AWAKE Stripline BPM

electronics, proton, MMI, TRIUMF

253

S. Liu, P.E. Dirksen, V.A. Verzilov
TRIUMF, Vancouver, Canada
S.J. Gessner, F. Guillot-Vignot, D. Medina, L. Søby
CERN, Geneva, Switzerland

Funding: # TRIUMF contribution was supported by NSERC and CNRC
AWAKE (The Advanced Proton Driven Plasma Wakefield Acceleration Experiment at CERN) stripline BPMs are required to measure the position of the single electron bunch to a position resolution of less than 10 µm rms for electron charge of 100 pC to 1 nC. This paper describes the design, installation and commissioning of a such BPM system developed by TRIUMF (Canada). Total 12 BPMs and electronics had been installed on AWAKE beam lines and started commissioning since Fall of 2017. The calibration and measurement performance are also reviewed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB01

About •

paper received ※ 04 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

TUPB02

Complete Test Results of New BPM Electronics for the ESRF New LE-Ring

electronics, SRF, controls, MMI

257

K.B. Scheidt
ESRF, Grenoble, France

Among the 320 BPMs in the ESRF new low emittance ring, a set of 128 units will be equipped with new electronics, while the other set (192) will be served by the existing Libera-Brilliance electronics. These new electronics are an upgraded version of the low-cost Spark electronics originally developed 3 years ago for the ESRF Injector complex. All these 128 units have been installed in the first half of 2018 on existing BPM signals (through duplication with RF-splitters) and subsequently been tested thoroughly for performance characteristics like stability, resolution and reliability. It will be shown that while these Sparks have a very straightforward and simple concept, i.e. completely omitting calibration schemes like RF-cross-bar switching, pilot-tone introduction or active temperature control, that they are fully compatible with all the beam position measurement requirements of this new ring.

Poster TUPB02 [1.577 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB02

About •

paper received ※ 30 August 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

TUPB03

Results of SPIRAL2 Beam Position Monitors on the Test Bench of the RFQ

linac, operation, rfq, electronics

261

M. Ben Abdillah, P. Ausset
IPN, Orsay, France
R. Ferdinand
GANIL, Caen, France

SPIRAL2 project is based on a multi-beam superconducting LINAC designed to accelerate 5 mA deuteron beams up to 40 MeV, proton beams up to 33 MeV and 1 mA light and heavy ions (Q/A = 1/3) up to 14.5 MeV/A. The accurate tuning of the LINAC is essential for the operation of SPIRAL2 and requires measurement of the beam transverse position, the phase of the beam with respect to the radiofrequency voltage, the ellipticity of the beam and the beam energy with the help of Beam Position Monitor (BPM) system. The commissioning of the RFQ gave us the opportunity to install two BPM sensors, associated with their electronics, mounted on a test bench. The test bench is a D-plate fully equipped with a complete set of beam diagnostic equipment in order to characterize as completely as possible the beam delivered by the RFQ and to gain experience with the behavior of these diagnostics under beam operation. This paper addresses the measurements carried with the two BPMs on the Dplate: energy, transverse position and ellipticity under 750 KeV proton beam operation

Poster TUPB03 [1.443 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB03

About •

paper received ※ 04 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

TUPB07

Stability Study of Beam Position Measurement Based on Higher Order Mode Signals at FLASH

HOM, cavity, dipole, higher-order-mode

273

J.H. Wei
USTC/NSRL, Hefei, Anhui, People’s Republic of China
N. Baboi
DESY, Hamburg, Germany
L. Shi
PSI, Villigen PSI, Switzerland

FLASH is a free-electron laser driven by a supercon-ducting linac at DESY in Hamburg. It generates high-brilliance XUV and soft X-ray pulses by SASE (Self Amplified Spontaneous Emission). Many accelerating cavities are equipped with HOMBPMs (Higher Order Mode based Beam Position Monitors) to align the beam and monitor the transverse beam position. However, these lose their position prediction ability over time. In this paper, we applied an efficient measurement and signal analysis with various data process methods including PLS (Partial Least Square) and SVD (Singular Value Decomposition) to determine the transverse beam position. By fitting the HOM signals with a genetic algorithm, we implemented a new HOMBPM calibration procedure and obtained reliable beam prediction positions over a long time. A stable RMS error of about 0.2 mm by using the spectra of signals and 0.15 mm by using the new method over two months has been observed.

Poster TUPB07 [1.816 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB07

About •

paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

TUPB09

The Evaluation of Beam Inclination Angle on the Cavity BPM Position Measurement

cavity, FEL, simulation, experiment

278

J. Chen, L.W. Lai, Y.B. Leng, L.Y. Yu, R.X. Yuan
SINAP, Shanghai, People’s Republic of China

Cavity beam position monitor (CBPM) is widely used to measure the transverse position in free-electron laser (FEL) and international linear collider (ILC) facilities due to the characteristic of high sensitive. In order to study the limiting factors of the position resolution of cavity BPM, the influence of beam inclination angle on the measure-ment of CBPM position and the direction of beam deflec-tion was analyzed. The simulation results show that the beam inclination angle is an important factor limiting the superiority of CBPM with extremely high position resolu-tion. The relative beam experiments to change the relative inclination angle between the cavity and the electron beam based on a 4-dimension moveable platform were performed in Shanghai Soft X-ray FEL (SXFEL) facility, the experiment results will also be mentioned as well.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB09

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

TUPB10

Design and Simulation of Stripline BPM for HUST Proton Therapy Facility

coupling, impedance, proton, dipole

281

J.Q. Li, Q.S. Chen, K. Fan, K. Tang, P. Tian
HUST, Wuhan, People’s Republic of China

Proton beams used in Huazhong University of Science and Technology Proton Therapy Facility（HUST-PTF）have extreme low currents of the order of nanoampere，which is a great challenge to beam diagnostics due to low signal level. Conventional destructive beam diagnostic devices will affect the quality of the beam and cannot work online during the patient treatment, so a non-destructive stripline beam position monitor (BPM) is designed. This study will introduce some analysis and simulation results of the stripline BPM, such as the coupling between the electrodes, impedance matching, signal response, etc. We also discussed how to increase the output signal by geometry optimization.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB10

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

TUPB13

Stability Tests with Pilot-Tone Based Elettra BPM RF Front End and Libera Electronics

electronics, real-time, instrumentation, FPGA

289

M. Cargnelutti, P. Leban, M. Žnidarčič
I-Tech, Solkan, Slovenia
S. Bassanese, G. Brajnik, S. Cleva, R. De Monte
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

Long-term stability is one of the most important properties of the BPM readout system. Recent developments on pilot tone capable front end have been tested with an established BPM readout electronics. The goal was to demonstrate the effectiveness of the pilot tone compensation to varying external conditions. Simulated cable attenuation change and temperature variation of the readout electronics were confirmed to have no major effect to position data readout. The output signals from Elettra front end (carrier frequency and pilot tone frequency) were processed by a Libera Spark with the integrated standard front end which contains several filtering, attenuation and amplification stages. Tests were repeated with a modified instrument (optimized for pilot tone) to compare the long-term stability results. Findings show the pilot tone front end enables great features like self-diagnostics and cable-fault compensation as well as small improvement in the long-term stability. Measurement resolution is in range of 10 nanometers RMS in 5 Hz bandwidth.

Poster TUPB13 [1.223 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB13

About •

paper received ※ 31 August 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

TUPB14

New Beam Position Monitors for the CERN LINAC3 to LEIR Ion Beam Transfer Line

linac, simulation, solenoid, vacuum

293

L. Søby, G. Baud, M. Bozzolan, R. Scrivens
CERN, Geneva, Switzerland

The injection line into the CERN Low Energy Ion Ring (LEIR) has recently been equipped with nine, new, electrostatic Beam Position Monitors (BPMs) in order to measure and optimize the trajectory of the low intensity ion beams coming from LINAC3. In this paper, we describe the design of the BPM, the low noise charge amplifier mounted directly on the BPM, and the digital acquisition system. There is special emphasis on the first commissioning results where the measured beam positions were seen to be perturbed by EMI and charging of the BPM electrodes by secondary particles. The effect of mitigation measures, including repelling voltages on the electrodes and external magnetic fields, are also discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB14

About •

paper received ※ 03 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC01

Australian Synchrotron BPM Electronics Upgrade

brilliance, coupling, synchrotron, storage-ring

297

Y.E. Tan, R.B. Hogan
AS - ANSTO, Clayton, Australia

The storage ring at the Australian Synchrotron (AS) was originally equipped with 98 Libera Electrons. In late 2017 all 98 of the BPM electronics has been upgraded to Libera Brilliance⁺ and the old Libera Electrons have been moved to the injection system. The transition process and results from commissioning the new system will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC01

About •

paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC03

Beam Quality Monitoring System in the HADES Experiment at GSI Using CVD Diamond Material

detector, monitoring, experiment, electronics

300

A. Rost, T. Galatyuk
TU Darmstadt, Darmstadt, Germany
J. Adamczewski-Musch, S. Linev, J. Pietraszko, M. Traxler
GSI, Darmstadt, Germany

Funding: Work supported by the DFG through GRK 2128 and VH-NG-823.
The beam quality monitoring of extracted beams from SIS18, transported to the HADES experiment, is of great importance to ensure high efficiency data recording. The main detector system used for this purpose is the Start-Veto system which consists of two diamond based sensors made of pcCVD and scCVD materials. Both sensors are equipped with a double-sided strip segmented metalization (300 µm width) which allows a precise position determination of the beam position. Those senors are able to deliver a time precision <100 ps and can handle rate capabilities up to 10⁷ particles/channel. The read-out of the sensors is based on the TRB3 system [1]. Precise FPGA-TDCs (264 channels, <10 ps RMS) are implemented inside FPGAs. The TRB3 system serves as data acquisition system with scaler capability. Analysis and on-line visualization will be performed in DABC [2]. Having the precise time measurement and a precise position information of the incoming beam ions one can monitor important beam parameters namely the beam intensity, its position during extraction and the beam time structure. In this contribution the general read-out concept will be introduced.
[1] A. Neiser et al., TRB3: a 264 channel high precision TDC platform and its applications, 2013 JINST 8 C12043.
[2] dabc.gsi.de, 30.05.2018

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC03

About •

paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC04

BPM System Upgrade at COSY

controls, EPICS, electronics, operation

303

V. Kamerdzhiev, I. Bekman, C. Böhme, B. Lorentz, S. Merzliakov, P. Niedermayer, K. Reimers, M. Simon, M. Thelen
FZJ, Jülich, Germany

The beam position monitoring system of the Cooler Synchrotron (COSY) has been upgraded in 2017. The upgrade was driven by the requirement of the JEDI collaboration to significantly improve the orbit control and by the electronics approaching end-of-life. The entire signal processing chain has been replaced. The new low noise amplifiers, mounted directly on the BPM vacuum feedthroughs, were developed in-house and include adjustable gain in 80 dB rage and in-situ test and calibration capabilities. The signals are digitized and processed by means of commercial BPM signal processing units featuring embedded EPICS IOC. The decision path, technical details of the upgrade and performance of the new system are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC04

About •

paper received ※ 13 September 2018 paper accepted ※ 14 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC05

Influence of Sampling Rate and Passband on the Performance of Stripline BPM

experiment, simulation, FEL, data-acquisition

307

T. Wu, S.S. Cao, F.Z. Chen, Y.B. Leng, Y.M. Zhou
SSRF, Shanghai, People’s Republic of China
J. Chen, L.W. Lai
SINAP, Shanghai, People’s Republic of China

It is obviously that the property of SBPM is influenced by data acquisition system, but how the procedure of data acquisition and processing takes effect is still room for enquiring into it. This paper will present some data simulation and experiment results to discuss the function between resolution and pass band, sampling rate or other influence factor. We hope that this paper would give some advice for building up data acquisition system of SBPM.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC05

About •

paper received ※ 05 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC07

First Results of Button BPMs at FRIB

electronics, linac, MMI, pick-up

311

S. Cogan, J.L. Crisp, T.M. Ford, S.M. Lidia
FRIB, East Lansing, USA

Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661, the State of Michigan and Michigan State University.
Commissioning and tuning the linac driver for the Facility for Rare Isotope Beams (FRIB) requires a large network of warm and cryogenic BPMs, with apertures of 40 - 150 mm, sensitivity to beam currents of 100 nA to 1 mA, and accurate for beams with velocities as low as 0.03c. We present initial results of the BPM system, analog and digital signal processing, distortion and error correction, and calibration for time of flight (TOF) measurements. Measurements for low energy beams are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC07

About •

paper received ※ 13 September 2018 paper accepted ※ 20 November 2018 issue date ※ 29 January 2019

Export •

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

TUPC09

Initial Results from the LHC Multi-Band Instability Monitor

detector, operation, synchrotron, betatron

314

T.E. Levens, T. Lefèvre, D. Valuch
CERN, Meyrin, Switzerland

Intra-bunch transverse instabilities are routinely measured in the LHC using a "Head-Tail Monitor" based on sampling a wide-band BPM with a high-speed digitiser. However, these measurements are limited by the dynamic range and short record length possible with typical commercial oscilloscopes. This paper will present the initial results from the LHC Multi-Band Instability Monitor, a new technique developed to provide information on the beam stability with a high dynamic range using frequency domain analysis of the transverse beam spectrum.

Poster TUPC09 [17.388 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC09

About •

paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC11

Design of an Ultrafast Stripline Kicker for Bunch-by-Bunch Feedback

kicker, FEL, impedance, HOM

322

J. Wang, P. Li, D. Wu, D.X. Xiao, L.G. Yan
CAEP/IAE, Mianyang, Sichuan, People’s Republic of China

Funding: Work supported by China National Key Scientific Instrument and Equipment Development Project (2011YQ130018), National Natural Science Foundation of China (11475159, 11505173, 11575264 and 11605190)
The CAEP THz Free Electron Laser (CTFEL) will have a fast transverse bunch-by-bunch feedback system on its test beamline, which is used to correct the beam position differences of individual bunches with interval of about 2 ns. In this paper, we are proposing an ultrafast wideband stripline kicker, which is able to provide a kick to the bunch in a 2 ns time window. The structure design and simulation results of this kicker are also discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC11

About •

paper received ※ 07 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC12

Beam Transverse Quadrupole Oscillation Measurement in the Injection Stage for the HLS-II Storage Ring

quadrupole, storage-ring, injection, betatron

325

F.F. Wu, F.L. Gao, L.T. Huang, X.Y. Liu, P. Lu, B.G. Sun, J.G. Wang, J.H. Wei, T.Y. Zhou
USTC/NSRL, Hefei, Anhui, People’s Republic of China

Funding: Supported by the National Science Foundation of China (Grant No. 11705203, 11575181, 11605202) and the National Key Research and Development Program of China(No. 2016YFA0402000)
Beam transverse quadrupole oscillation can be excited in the injection stage if injected beam parameters(twiss parameters or dispersion) are not matched with the parameters in the injection point of the storage ring. In order to measure the beam transverse quadrupole oscillation in the injection stage for the HLS-II storage ring, some axially symmetric stripline BPMs were designed. Transverse quadrupole component for these BPMs was simulated and off-line calibrated. Beam transverse quadrupole oscillation has been measured when beam was injected into the HLS-II electron storage ring. The spectrum of the transverse quadrupole component showed that beam transverse quadrupole oscillation is very obvious in the injection stage and this oscillation isn’t the second harmonic of beam betatron oscillation. The relationship between transverse quadrupole oscillation and beam current was also analyzed and the result shows that the relationship is not linear.

Poster TUPC12 [0.467 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC12

About •

paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC13

Early Commissioning of the Luminosity Dither Feedback for SuperKEKB

luminosity, feedback, MMI, controls

328

M. Masuzawa, Y. Funakoshi, T. Kawamoto, S. Nakamura, T. Oki, M. Tobiyama, S. Uehara
KEK, Ibaraki, Japan
P. Bambade, S. Di Carlo, D. Jehanno, C.G. Pang
LAL, Orsay, France
D.G. Brown, A.S. Fisher, M.K. Sullivan
SLAC, Menlo Park, California, USA
D. El Khechen
CERN, Geneva, Switzerland
U. Wienands
ANL, Argonne, Illinois, USA

SuperKEKB is an electron-positron collider, which aims to achieve a peak luminosity of 8×10³⁵ cm^-2 s⁻¹ using what is known as the "nano-beam" scheme. This paper reports on the commissioning and performance of a luminosity dither feedback. The system, based on one previously used at SLAC for PEP-II, is employed for collision orbit feedback in the horizontal plane. Twelve air-core Helmholtz coils drive the positron beam sinusoidally at a frequency near 80 Hz, forming a closed bump at the interaction point. A lock-in amplifier detects the amplitude and phase of the corresponding frequency component of the luminosity signal. When the beams are aligned for peak luminosity, the magnitude of the luminosity component at the dithering frequency becomes zero. The magnitude grows as the beams are offset, and the phase shifts by 180 degrees when the direction of the necessary correction reverses. The hardware and algorithm were tested during SuperKEKB Phase II run. The electron beam orbit was successfully adjusted to minimize the amplitude of the dither frequency component of the luminosity signal, and the optimal condition was maintained by continuously adjusting the electron beam orbit.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC13

About •

paper received ※ 09 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019

Export •

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

WEOA02

Optical Investigation to Minimize the Electron Bunch Arrival-time Jitter Between Femtosecond Laser Pulses and Electron Bunches for Laser-Driven Plasma Wakefield Accelerators

laser, plasma, ECR, polarization

332

S. Mattiello, A. Penirschke
THM, Friedberg, Germany
H. Schlarb
DESY, Hamburg, Germany

Funding: The work of S. Mattiello is supported by the German Federal Ministry of Education and Research (BMBF) within the Project ’ MAKE-PWA.
In a laser driven plasma based particle accelerators a stable synchronization of the electron bunch and of the plasma wakefield in the range of less than 2 fs is necessary in order to optimize the acceleration. For this purpose we are developing a new shot to shot feedback system with a time resolution of less than 1 fs. As a first step, stable THz pulses are generated by optical rectification of a fraction of the plasma generating high energy laser pulses in a nonlinear lithium niobate crystal. It is planed that the generated THz pulses will energy modulate the electron bunches shot to shot before the plasma to achieve the time resolution of 1 fs. In this contribution we systematically investigate the influence of the optical properties as well as the theoretical description of the THz generation on the conversion efficiency of the generation of short THz pulses in undepleted approximation. We compare different approximations for the modeling of the generation dynamics and of the dielectric function in order to investigate the importance of a detailed description of the optical properties. First results by considering intensity decreasing of the laser pump will be presented.
*The feedback system will be tested at the Accelerator R&D facility SINBAD (Short Innovative Bunches and Accelerators at DESY).

Slides WEOA02 [1.605 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOA02

About •

paper received ※ 04 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019

Export •

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

WEOA03

First Electro-Optical Bunch Length Measurements from the European XFEL

laser, FEL, optics, detector

338

B. Steffen, M.K. Czwalinna, C. Gerth, P. Peier
DESY, Hamburg, Germany

Three electro-optical bunch length detection systems based on spectral decoding have been installed and are being commissioned at the European XFEL. The systems are capable of recording individual longitudinal bunch profiles with sub-picosecond resolution at a bunch repetition rate 1.13 MHz. Bunch lengths and arrival times of entire bunch trains with single-bunch resolution have been measured as well as jitter and drifts for consecutive bunch trains. In this paper, we present first measurement results for the electro-optical detection system located after the second bunch compressor. A preliminary comparison with data from the bunch arrival-time monitor shows good agreement.

Slides WEOA03 [4.496 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOA03

About •

paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEOA04

The Application of Beam Arrival Time Measurement at SXFEL

cavity, FEL, experiment, laser

342

S.S. Cao, J. Chen, Y.B. Leng, R.X. Yuan
SINAP, Shanghai, People’s Republic of China

Shanghai soft X-ray free electron laser (SXFEL) is able to generate high brightness and ultra-short light pulses. The generation of the light sources relies on the synchronization between seeded laser and electron bunch. Beam arrival time play an important role to keep the synchronization. For the SXFEL, a beam arrival time resolution under 100 fs is required. In this paper, the application of beam arrival time measurement scheme on SXFEL has been presented. The whole BAM system consists of four parts: beam arrival time monitor, electronic front-end, signal acquisition system, and high-level signal processing and presentation. Currently, four sets of beam arrival time monitors (BAMs) have been installed in the SXFEL and distributed in four different locations. The relevant beam arrival time experiment and beam flight time experiment based on the dual-cavities mixing method have also been performed so as to evaluate and analyze the beam status.

Slides WEOA04 [4.588 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOA04

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEOB02

RadFET Dose Monitor System for SOLEIL

radiation, electronics, storage-ring, vacuum

353

N. Hubert, F. Dohou, M. El Ajjouri, D. Pédeau
SOLEIL, Gif-sur-Yvette, France

Soleil is currently testing new dose monitors based on RadFET transistors. This new detector at SOLEIL will provide a measurement of the dose received by equipment that are damaged by the radiations in the storage ring, and to anticipate their replacement. This monitor should be very compact to be placed in tiny areas, sensitive to all kind of radiation and low cost to install many of them around the ring. A readout electronic module is being developed in-house, and a first prototype has been build and installed on the machine. Description of the system and first results recorded on the machine are presented.

Slides WEOB02 [4.250 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOB02

About •

paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEOB03

The European XFEL Beam Loss Monitor System

FEL, high-voltage, controls, undulator

357

T. Wamsat, T. Lensch
DESY, Hamburg, Germany

The European XFEL MTCA based Beam Loss Monitor System (BLM) is composed of about 470 monitors, which are part of the Machine Protection System (MPS). The BLMs detect losses of the electron beam, in order to protect accelerator components from damage and excessive activation, in particular the undulators, since they are made of permanent magnets. Also each cold accelerating module is equipped with a BLM to measure the sudden onset of field emission (dark current) in cavities. In addition some BLMs are used as detectors for wire- scanners. Experience from the already running BLM system in FLASH2 which is developed for XFEL and tested here, led to a fast implementation of the system in the XFEL. Further firmware and server developments related to alarm generation and handling are ongoing. The BLM systems structure, the current status and the different possibilities to trigger alarms which stop the electron beam will be presented.

Slides WEOB03 [3.631 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOB03

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEOC02

Review of Recent Status of Coded Aperture X-ray Monitors for Beam Size Measurement

detector, optics, emittance, MMI

361

J.W. Flanagan
KEK, Ibaraki, Japan

Funding: US-Japan Cooperation in High Energy Physics (Japan Monbukagakusho and US DOE). Kakenhi.
X-ray beam profile monitors based on coded aperture imaging use an array of pinholes or slits to achieve large open apertures, which provide improved photon collection efficiency over single pinholes or slits. The resulting improvement in photon statistics makes possible single-bunch, single-turn measurements at lower bunch currents than are possible with a single pinhole or slit. In addition, the coded aperture pattern provides extra information for beam profile reconstruction, which makes possible somewhat improved resolution, as compared to a single slit. The reconstruction algorithm for coded aperture imaging is more complicated and computing-intensive than that for a single slit, though with certain classes of coded pertures a faster reconstruction method is possible. This talk will provide a survey of efforts to use coded aperture imaging for beam profile diagnostics at accelerators to date, covering principles and practical experiences with the technique, as well as prospects for the future at SuperKEKB, where it forms the primary means of measuring vertical beam sizes.

Slides WEOC02 [4.065 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOC02

About •

paper received ※ 12 September 2018 paper accepted ※ 24 September 2018 issue date ※ 29 January 2019

Export •

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

WEOC03

A Simple Model to Describe Smoke Ring Shaped Beam Profile Measurements With Scintillating Screens at the European XFEL

FEL, diagnostics, scattering, ECR

366

G. Kube, S. Liu, A.I. Novokshonov, M. Scholz
DESY, Hamburg, Germany

Standard beam profile measurements of high-brightness electron beams based on OTR may be hampered by coherence effects. Therefore it was decided for the European XFEL to measure transverse beam profiles based on scintillating screen monitors using LYSO:Ce. While it is possible to resolve beam sizes down to a few micrometers with this scintillator, the experience during the XFEL commissioning showed that the measured emittance values were significantly larger than the expected ones. In addition, beam profiles measured at bunch charges of a few hundred pC showed a ’smoke ring’ structure. While coherent OTR emission and beam dynamical influence can be excluded, it is assumed that the profile distortions are caused by effects from the scintillator material. Following the experience in high energy physics, a simple model was developed which takes into account quenching effects of excitonic carriers inside a scintillator in a heuristic way. Based on this model, the observed beam profiles can be understood qualitatively. Together with the model description, first comparisons with experiments will be presented, and new scintillators suitable for beam profile diagnostics will be discussed.

Slides WEOC03 [2.411 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOC03

About •

paper received ※ 04 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

WEOC04

Space Charge Effects Studies for the ESS Cold Linac Beam Profiler

space-charge, simulation, proton, HOM

371

F. Belloni, P. Abbon, F. Benedetti, G. Coulloux, F. Gougnaud, C. Lahonde-Hamdoun, P. Le Bourlout, Y. Mariette, J. Marroncle, J.-Ph. Mols, V. Nadot, L. Scola
CEA-DRF-IRFU, France
C.A. Thomas
ESS, Lund, Sweden

Five Ionization Profile Monitors are being built by CEA in the framework of the in-kind contribution agreement signed with ESS. The IPMs will be installed in the Cold Linac where the proton energy range they need to cover extends from 90 MeV to 2 GeV. The ESS fields intensity of 1.10⁺⁰⁹ protons/bunch delivered at a frequency of 352 or 704 MHz, with a duty cycle of 4%, may strongly affect the trajectories of the ionized molecules and electrons created by the passage of the beam through the residual gas. In order to quantify and to develop a correction algorithm for these space charge effects, a code was initiated at ESS and completed at CEA Saclay with the possibility to include real case electric fields calculated with Comsol Multiphysics. A general overview of the code and its preliminary results are presented here.

Slides WEOC04 [5.186 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOC04

About •

paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEPA09

Long Term Beam Phase Monitoring Based on HOM Signals in SC Cavities at FLASH

HOM, cavity, controls, FEL

388

J.H. Wei
USTC/NSRL, Hefei, Anhui, People’s Republic of China
N. Baboi
DESY, Hamburg, Germany
L. Shi
PSI, Villigen PSI, Switzerland

The accelerating RF fields in superconducting cavities must be controlled precisely in FEL (Free Electron Laser) facilities to avoid beam energy spread and arrival time jitter. Otherwise the beam quality is degraded. The LLRF (Low Level Radio Frequency) system controls the RF field and provides a highly stable RF reference. A new type of beam phase determination technique based on beam-excited HOMs (Higher Order Modes) in cavities has been implemented. The two special couplers installed at both ends of each cavity, pick up the signals containing both the leakage of the accelerating field and the HOM signals. Therefore the signals can be used to calculate the beam phase directly with respect to the RF phase. We analysed the factors which may affect the result of the beam phase on a long-term based on an experimental platform at FLASH. Some phase drifts between the HOM-BPhM (Beam Phase Monitor) and the LLRF system phase measurement were observed and the reason will be further studied.

Poster WEPA09 [1.720 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA09

About •

paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

WEPA12

Differential Evolution Genetic Algorithm for Beam Bunch Temporal Reconstruction

radiation, laser, FEL, experiment

392

D. Wu, T.H. He, C.L. Lao, P. Li, J. Liu, X. Luo, Q. Pan, L.J. Shan, X. Shen, J. Wang, D.X. Xiao, L.G. Yan, P. Zhang, K. Zhou
CAEP/IAE, Mianyang, Sichuan, People’s Republic of China
Y. Liu
CAEP/IFP, Mainyang, Sichuan, People’s Republic of China

Funding: Work supported by China National Natural Science Foundation of China with grant (11475159, 11505173, 11505174, 11575264, 11605190 and 11105019)
Coherent radiation, such as coherent transition radiation, coherent diffraction radiation, coherent synchrotron radiation, etc, can be used to measure the longitudinal distribution of the electron beam bunch of any length, as long as the coherent radiation spectrum can be measured. In many cases, the Kramers-Krönig relationship is used to reconstruct the temporal distribution of the beam from the coherent radiation spectrum. However, the extrapolation of the low frequency will introduce the uncertainty of the reconstruction. In this paper, an algorithm of differential evolution (DE) for temporal reconstruction is discussed. The DE reconstruction works well for the complex and ultrashort distribution. It will be an effectIve tool to accurately measure the femtosecond bunch temporal structure.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA12

About •

paper received ※ 07 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

WEPA13

Electro-Optic Modulator Based Beam Arrival Time Monitor for SXFEL

FEL, pick-up, timing, laser

396

X.Q. Liu, L.F. Hua, L.W. Lai, Y.B. Leng, R.X. Yuan
SINAP, Shanghai, People’s Republic of China
N. Zhang
SSRF, Shanghai, People’s Republic of China

Beam arrival time monitor (BAM) is an important tool to investigate the temporal characteristic of elec-tron bunch in free electron laser (FEL) like Shanghai soft X-ray Free Electron Laser (SXFEL). Since the timing jitter of electron bunch will affect the FEL’s stability and the resolution of time-resolved experi-ment at FELs, it is necessary to precisely measure the electron bunch arrival time so as to reduce the timing jitter of the electron bunch with beam based feedback. The beam arrival time monitor based on electro-optic modulator (EOM) is already planned and will be de-veloped and tested at SXFEL in the next three years. Here the design and preliminary results of the EOM based beam arrival time monitor will be introduced in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA13

About •

paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEPA15

Development of BAM Electronics in PAL-XFEL

electronics, pick-up, controls, site

400

D.C. Shin, J.H. Hong, H.-S. Kang, C. Kim, G. Kim, C.-K. Min
PAL, Pohang, Republic of Korea

We describe an electronics for electron bunch arrival time monitor (BAM) with a less than 10 femtosecond resolution, which was developed in 2017 and is currently in use at PAL-XFEL. When electron bunches go through an S-band monopole cavity, about 1 us long RF signal can be obtained to compare with a low phase noise RF reference. The differential phase jitter corresponds to the arrival time jitter of electron bunches. RF front-end (F/E) which converts the S-band pickup signal to intermediate frequency (IF) signal, is the essential part of a good time resolution. The digitizer and the signal processor of the BAM electronics are installed in an MTCA platform. This paper presents the design scheme, test results of the BAM electronics and future improvement plans.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA15

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEPA16

Micro-Bunching Instability Monitor for X-ray Free Electron Laser

radiation, bunching, laser, linac

404

C. Kim, H.-S. Kang, G. Kim, I.S. Ko
PAL, Pohang, Kyungbuk, Republic of Korea
J.H. Ko
POSTECH, Pohang, Kyungbuk, Republic of Korea

A direct method was developed to measure the micro-bunching instability in the X-ray Free Electron Laser (XFEL). The micro-bunching instability comes from the interaction between the electron beam and the coherent synchrotron radiation (CSR), and the FEL intensity can be affected significantly by the micro-bunching instability. However, no effective method had been introduced to monitor the micro-bunching instability, so that we installed a CCD camera to measure the micro-bunching instability after the bunch compressor. The CCD camera showed the micro-bunching instability successfully, and more interesting features of the micro-bunching instability were revealed from it.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA16

About •

paper received ※ 09 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEPA17

Development, Fabrication and Laboratory Tests of Bunch Shape Monitors for ESS Linac

dipole, quadrupole, target, space-charge

407

S.A. Gavrilov, D.A. Chermoshentsev, A. Feschenko
RAS/INR, Moscow, Russia

Two Bunch Shape Monitors have been developed and fabricated in INR RAS for European Spallation Source linac. To fulfil the requirements of a 4 ps phase resolution the symmetric λ-type RF-deflector based on the parallel wire line with capacitive plates has been selected. Additional steering magnet to correct incline of the focused electron beam is also used. Limitations due to space charge of the analysed beam and due to external magnetic fields are discussed. The results of the laboratory tests of the monitors are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA17

About •

paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEPA18

Development of Longitudinal Beam Profile Diagnostics for Beam-beam Effects Study at VEPP-2000

synchrotron, positron, collider, injection

410

M.V. Timoshenko, V.M. Borin, O.I. Meshkov, Yu. A. Rogovsky, D.B. Shwartz, Yu.M. Zharinov
BINP SB RAS, Novosibirsk, Russia
V.L. Dorokhov
BINP, Novosibirsk, Russia

The comprehensive development of beam longitudinal profile measurement systems based on stroboscopic optical dissector has started at VEPP-2000 electron-positron collider complex. The dissector was setted and commissioned at booster ring BEP that was deeply upgraded (2013-2015) to achieve top energy of 1 GeV. Bunch lengthening with current was studied at BEP with its new RF-cavity. In addition the method of synchrotron frequency measurement by dissector was applied. After dissector checkouts at BEP the similar studies were carried out with a single beam at VEPP-2000 storage ring in parallel with streak-camera measurements. Good agreement of results was observed. Series of single-turn longitudinal and vertical bunch profiles snapshots was made by streak-camera with respect to delay after counter beam injection. The unexpected longitudinal beam dynamics was observed for intensities above the beam-beam threshold. These studies together with beam-beam coherent oscillations spectra seen by pickups are of a great interest for understanding of flip-flop phenomenon which establish a fundamental luminosity limit at VEPP-2000 operating with round beams.

Poster WEPA18 [2.269 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA18

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEPA19

Results from the CERN LINAC4 Longitudinal Bunch Shape Monitor

linac, cavity, MMI, emittance

415

J. Tan, G. Bellodi
CERN, Geneva, Switzerland
A. Feschenko, S.A. Gavrilov
RAS/INR, Moscow, Russia

The CERN Linac4 has been successfully commissioned to its nominal energy and will provide 160 MeV H⁻ ions for charge-exchange injection into the Proton Synchrotron Booster (PSB) from 2020. A complete set of beam diagnostic devices has been installed along the accelerating structures and the transfer line for safe and efficient operation. This includes two longitudinal Bunch Shape Monitors (BSM) developed by the Institute for Nuclear Research (INR, Moscow). Setting-up the RF cavities of Linac4 involves beam loading observations, time-of-flight measurements and reconstruction of the longitudinal emittance from phase profile measurements. In this paper the BSM is presented along with some results obtained during accelerator commissioning, including a comparison with phase measurements performed using the Beam Position Monitor system.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA19

About •

paper received ※ 07 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEPA20

First Results From the Bunch Arrival-Time Monitors at SwissFEL

laser, FEL, pick-up, MMI

420

V.R. Arsov, P. Chevtsov, S. Hunziker, M.G. Kaiser, D. Llorente Sancho, A. Romann, V. Schlott, M. Stadler, D.M. Treyer
PSI, Villigen PSI, Switzerland
M. Dach
Dach Consulting GmbH, Brugg, Switzerland

Two Bunch Arrival-Time Monitors (BAM), based on fiber optical Mach-Zehnder intensity modulators, which encode the arrival-time information in the amplitude of the laser pulses delivered through a highly stable pulsed optical reference distribution system, have been commissioned and are operational at SwissFEL. The first BAM is at the RF-Gun, the second one is downstream the first bunch compressor. Both BAMs operate simultaneously and measure the arrival-time drift and jitter with less than 5 fs resolution. For the first time we have experimentally verified the excellent SwissFEL bunch stability. We have developed concepts and tested hardware, which enhance the commissioning and user operation. In particular we have successfully tested a tool for fast timing overlap between the electron bunch and the reference laser pulse, which allows fast system set-up and characterization. We have verified the capability for 2-bunch and 100 Hz operation. In comparison to the prototype detectors, which were operational at the SwissFEL test injector, we have achieved an improved BAM resolution in the range 10 pC - 200 pC.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPA20

About •

paper received ※ 05 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEPB04

Comparison of YAG Screens and LYSO Screens at PITZ

HOM, emittance, laser, distributed

438

R. Niemczyk, P. Boonpornprasert, Y. Chen, J.D. Good, M. Groß, H. Huck, I.I. Isaev, D.K. Kalantaryan, C. Koschitzki, M. Krasilnikov, X. Li, O. Lishilin, G. Loisch, D. Melkumyan, A. Oppelt, H.J. Qian, Y. Renier, F. Stephan, Q.T. Zhao
DESY Zeuthen, Zeuthen, Germany
W. Hillert
University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany

The Photo Injector Test facility at DESY in Zeuthen (PITZ) is dedicated to the development of high-brightness electron sources for free-electron lasers. At PITZ, to measure the emittance of space-charge-dominated beams, the slit scan technique is used. For slice emittance measurements a transverse deflecting structure (TDS) is employed. The electron beam distribution is measured by means of scintillator screens. Both the TDS and the slit mask reduce the signal strength, giving stringent requirements on the sensitivity of the screens. At PITZ, high-sensitivity Ce:LYSO screens have been installed at the same screen stations as the standard Ce:YAG screens to solve low-intensity issues. A comparison of both screens is presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB04

About •

paper received ※ 03 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEPB09

Wire Scanner Measurements at the PAL-XFEL

undulator, FEL, emittance, controls

445

G. Kim, H.-S. Kang, C. Kim, B.G. Oh, D.C. Shin
PAL, Pohang, Kyungbuk, Republic of Korea

The PAL-XFEL, an X-ray Free electron laser user facility based on a 10 GeV normal conducting linear accelerator, have been operational at Pohang, South Korea. The wire scanners are installed for transverse beam profile measurement of the Linac and the Hard X-ray undulator section. The wire scanner is a useful device for emittance measurements in the Hard X-ray undulator section. In this paper, we describe the details of the wire scanner and the results of the measurements.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB09

About •

paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEPB10

Grating Scanner for Measurement of Micron-size Beam Profiles

photon, simulation, positron, collider

448

L.G. Sukhikh, A. Potylitsyn, S.A. Strokov
TPU, Tomsk, Russia
G. Kube, K. Wittenburg
DESY, Hamburg, Germany

Funding: The work was partly supported by the program ‘‘Nauka’ of the Russian Ministry of Education and Science, grant # 3.1903.2017
Wire scanners are widely used for transverse beam size diagnostics. The minimum detectable beam size is affected by the diameter of a single wire. The smallest carbon or tungsten wires used so far have diameters of about 4 microns. With the development of modern electron accelerators and the demands from future linear electron-positron colliders, sub-micron beam sizes have to be resolved. In order to increase the resolution, the decrease of the wire diameter is required. The authors of Ref. * proposed to manufacture thin gold stripes of rectangular shape (widths are equal to 1 µm or 2 µm and height is equal to 3 µm) on Si₃N₄ membrane. We propose to use another arrangement of gold stripes with varying period on a Si substrate. A set of 11 stripes with 1 µm width and 10 micron height with varying gap width in the range 3-0.25 µm ("grating scanner") was simulated by using an analytical model and by the Geant4 code. By moving this scanner across the beam one could measure the Bremsstrahlung yield vs. the coordinate, resulting in an oscillating dependence. The visibility of the resulting image allows defining the beam sizes in the range of 0.5-1.5 µm for the proposed scanner parameters.
* S. Borrelli et al., "Generation and Measurement of Sub-Micrometer Relativistic Electron Beams", arXiv:1804.04252v1 [physics.acc-ph] 11 Apr 2018

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB10

About •

paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEPB11

Spatial Resolution Improvement of OTR Monitors by Off-axis Light Collection

radiation, target, diagnostics, photon

451

A. Potylitsyn, A.I. Novokshonov, L.G. Sukhikh
TPU, Tomsk, Russia
G. Kube, A.I. Novokshonov
DESY, Hamburg, Germany

Funding: The work was partly supported by the program "Nauka" of the Russian Ministry of Education and Science, grant #3.1903.2017
The spatial resolution of an OTR monitor for electron beam profile diagnostics is determined by the resolution of the optical system and by the Point Spread Function (PSF) representing the single electron image. In the image plane, the PSF has a typical lobe-shape distribution with an inter-peak distance depending on wavelength and lens aperture ratio [*]. For a beam with a transverse rms size smaller than the distance, the reconstruction of the beam profile has several difficulties [**, ***]. We propose to reduce the PSF contribution and to improve the spatial resolution of an OTR monitor simply by rotating the lens optical axis with respect to the specular reflection direction. If the difference between the rotational angle and the lens aperture is much larger than the inverse Lorentz factor, the PSF has a Gaussian-like distribution which matches practically with the Airy distribution. Thus the resolution depends on wavelength and lens aperture. In principle, for lens apertures in the order of 0.1 rad such an approach should allow to measure beam sizes comparable to the wavelength of observation, using a simple deconvolution procedure for the measured image and the PSF.
* M. Castellano, V.Verzilov, Phys. Rev. ST-AB, 1 (1998).
** K.Kruchinin, S.T.Boogert, P.Karataev et al., Proc. IBIC 2013 (2013).
*** L.G. Sukhikh, A.P. Potylitsyn, G. Kube, Phys. Rev. AB 20 (2017).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB11

About •

paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEPB15

A Multipurpose Scintillating Fibre Beam Monitor for the Measurement of Secondary Beams at CERN

experiment, detector, electronics, secondary-beams

468

I. Ortega Ruiz, L. Fosse, J. Franchi, A. Frassier, J. Fullerton, J. Kral, J. Lauener, T. Schneider, J. Spanggaard, G. Tranquille
CERN, Meyrin, Switzerland

A scintillating fibre beam monitor has been developed at CERN for the measurement of low energy and low intensity secondary beams. This monitor can track the passage of individual particles up to intensities of 10⁷ particles per second per mm², over an active area of 20 cm x 20 cm, and with a spatial resolution of 1 mm. Thanks to an external trigger system, the achieved detection efficiency is 95% and the noise level is kept below 10^-4 events/second. The simple design of this monitor avoids the common production difficulties of scintillating fibre detectors and makes its maintenance easier, when compared to other tracking detectors, due to the absence of gas or cooling. Using special electronics, a version of the monitor can also be used for time-of-flight measurements, achieving a time resolution of 900 ps. Thanks to its versatility, the monitor will perform several functions when measuring the secondary beams of the CERN Neutrino Platform: beam profile, position and intensity measurement, magnetic momentum spectrometry, particle identification through time-of-flight, and trigger generation for the experiments.

Poster WEPB15 [1.172 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB15

About •

paper received ※ 03 September 2018 paper accepted ※ 14 September 2018 issue date ※ 29 January 2019

Export •

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

WEPB16

Development of a Beam-Gas Curtain Profile Monitor for the High Luminosity Upgrade of the LHC

proton, simulation, vacuum, photon

472

R. Veness, M. Ady, N. Chritin, J. Glutting, O.R. Jones, R. Kersevan, T. Marriott-Dodington, S. Mazzoni, A. Rossi, G. Schneider
CERN, Meyrin, Switzerland
P. Forck, S. Udrea
GSI, Darmstadt, Germany
A. Salehilashkajani
The University of Liverpool, Liverpool, United Kingdom
P. Smakulski
WRUT, Wroclaw, Poland
C.P. Welsch, H.D. Zhang
Cockcroft Institute, Warrington, Cheshire, United Kingdom

High luminosity upgrades to the LHC at CERN and future energy frontier machines will require a new generation of minimally invasive profile measurement instruments. Production of a dense, focussed gas target allows beam-gas fluorescence to be exploited as an observable, giving an instrument suitable for installation even in regions of high magnetic field. This paper describes the development of a device based on these principles that would be suitable for operation in the LHC. It focusses on mechanisms for the production of a homogeneous gas curtain, the selection of an appropriate working gas and the optical fluorescence detection system.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB16

About •

paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

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

WEPB18

Performance of a Reflective Microscope Objective in an X-ray Pinhole Camera

target, photon, emittance, storage-ring

477

L. Bobb, G. Rehm
DLS, Oxfordshire, United Kingdom

X-ray pinhole cameras are used to measure the transverse beam profile of the electron beam in the storage ring from which the emittance is calculated. As improvements to the accelerator lattice reduce the beam emittance, e.g. with upgrades to fourth generation synchrotron light sources, likewise the beam size will be reduced such that micron and sub-micron scale resolution is required for beam size measurement. Therefore the spatial resolution of the pinhole camera imaging system must be improved accordingly. Here, the performance of a reflective microscope objective is compared to the high quality refractive lens which is currently in use to image the scintillator screen to the camera. The modulation transfer functions for each system have been assessed and will be discussed.

Poster WEPB18 [0.751 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB18

About •

paper received ※ 04 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEPB20

Experimental Setup of Apodization Techniques for Beam Diagnostics Performed at ELBE

experiment, diagnostics, LabView, software

482

B.G. Freeman, J. Gubeli, K. Jordan
JLab, Newport News, Virginia, USA
P.E. Evtushenko
HZDR, Dresden, Germany

The ELBE (Electron Linac for beams with high Brilliance and low Emittance) facility in Dresden, Germany is a multipurpose user facility, which is also used for accelerator R&D purposes. The beam line was set up for transverse beam profile measurements, where the imaging system includes a series of three apodizers and five circular apertures. During beam operations both of these were changed remotely through automated LabView routines. The bunch structure and charge were varied to collect a series of images that were acquired automatically, and then stored for later analysis. Over 12,000 images were captured and then analyzed using software written at Jefferson Lab that runs ImageJ as it’s main image processing library.

Poster WEPB20 [0.357 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB20

About •

paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEPB21

Transverse Beam Emittance Measurements with Multi-Slit and Moving-Slit Devices for LEReC

emittance, cavity, optics, solenoid

486

C. Liu, A.V. Fedotov, D.M. Gassner, X. Gu, D. Kayran, J. Kewisch, T.A. Miller, M.G. Minty, V. Ptitsyn, S. Seletskiy, A. Sukhanov, D. Weiss
BNL, Upton, Long Island, New York, USA
A. Fuchs
Ward Melville High School, Setauket- East Setauket, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Low Energy RHIC electron cooling (LEReC) [1] is the first bunched electron cooler, designed to cool low energy ion beams at RHIC. The beam quality, including the transverse beam emittance, is critical for the success of cooling. The transverse electron beam emittance was characterized with a multi-slit and moving-slit device at various locations in the beamline. The beam emittance measurement and analysis are presented in this report.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB21

About •

paper received ※ 01 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEPC04

Setup for Beam Profile Measurements using Optical Transition Radiation

target, radiation, linac, diagnostics

494

J. Pforr, M. Arnold, T. Bahlo, L.E. Jürgensen, N. Pietralla, A. Rost
TU Darmstadt, Darmstadt, Germany
F. Hug
KPH, Mainz, Germany

Funding: Work supported by DFG through GRK 2128.
The S-DALINAC is a thrice-recirculating, superconducting linear electron accelerator at TU Darmstadt. It can provide beams of electrons with energies up to 130 MeV and currents of 20 µA. The accelerator performance was improved by an extension of the beam diagnostics, as this increases the reproducibility of the machine settings. Therefore, the installation of several beam profile measurement stations is planned, which should be operational down to a beam current of 100 nA, as this current is used for beam tuning. Combining these devices with a quadrupole scan also allows for emittance measurements. The beam profile measurements shall be done based on optical transition radiation (OTR), resulting from the penetration of relativistic electrons from vacuum into a metal target. The radiation can be detected using standard cameras that provide information on the two-dimensional particle distribution. This contribution will address the layout of the measurement stations and a first test measurement will be presented.

Poster WEPC04 [1.189 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPC04

About •

paper received ※ 03 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

WEPC06

The New Diagnostic Suite for the Echo Enabled Harmonic Generation Experiment at FERMI

laser, FEL, diagnostics, detector

501

M. Veronese, A. Abrami, E. Allaria, M. Bossi, I. Cudin, M.B. Danailov, R. De Monte, M. Ferianis, F. Giacuzzo, S. Grulja, G. Kurdi, P. Rebernik Ribič, R. Sauro, G. Strangolino
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

The Echo Enabled Harmonic Generation (EEHG) experiment has been implemented on the FEL2 line of the FERMI FEL at Elettra (Italy). The main purpose is to validate the expected performance improvements at short wavelengths before a dedicated major upgrade is deployed. This paper describes the new diagnostics and the operational experience with them during the EEHG experiment. By means of a multi position vacuum vertical manipulator, different optical components are positioned on the electron and seed laser path. Both transverse and longitudinal measurements are performed. A YAG:Ce screen (e beam) and a terbium doped UV scintillator (laser) are imaged on a dedicated CMOS camera. For the temporal alignment, an OTR screen and a scattering surface are used to steer radiation from the e-beam and laser, onto a fast photodetector. Also coherent OTR radiation, due to micro-bunching, is acquired by means of a PbSe photodetector. Finally, for the normal EEHG operation, the laser beam is injected on the electron beam axis by means of a UV reflecting mirror. The results of the installed diagnostics commissioning are here presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPC06

About •

paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

WEPC17

X-ray Pinhole Camera in the Diagnostics Beamlime BL7B at PLS-II

photon, diagnostics, radiation, beam-diagnostic

519

J.J. Ko, J.Y. Huang, D. Kim, D.W. Lee, B.H. Oh, S. Shin, J. U. Yu
PAL, Pohang, Kyungbuk, Republic of Korea
M. Yoon
POSTECH, Pohang, Kyungbuk, Republic of Korea

The beam diagnostics beamline BL7B using synchrotron radiation with 8.6 keV critical photon energy from bending magnet has been used to measure the electron-beam size and photon-beam profile on real-time basis. After the completion of the PLS-II, the Compound Refractive Lens (CRL) system was implemented in the optical hutch at BL7B to measure the electron-beam size from X-ray imaging. But we could not have a good image due to short focal length caused by limited space of the optical hutch. To solve this problem a Pinole Camera is implemented in the front-end of BL7B in return for the beamline extension. The progresses on the new x-ray imaging system is introduced in this presentation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPC17

About •

paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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