LINAC2012 - List of Keywords (cavity)

Paper	Title	Other Keywords	Page
SUPB004	Linac Optics Design for Multi-turn ERL Light Source	linac, optics, acceleration, cryomodule	7
	Y. Petenev, T. Atkinson, A.V. Bondarenko, A.N. Matveenko HZB, Berlin, Germany
	The optics simulation group at HZB is designing a multi-turn energy recovery linac-based light source. Using the superconducting Linac technology, the Femto-Science-Factory (FSF) will provide its users with ultra-bright photon beams of angstrom wavelength at 6 GeV. The FSF is intended to be a multi-user facility and offer a variety of operation modes. In this paper a design of transverse optic of the beam motion in the Linacs is presented. An important point in the optics design was minimization of the beta-functions in the linac at all beam passes to suppress beam break-up (BBU) instability.

SUPB009	Linear Accelerator based on Parallel Coupled Accelerating Structure	electron, controls, focusing, klystron	19
	A.E. Levichev, A.M. Barnyakov, V.M. Pavlov BINP SB RAS, Novosibirsk, Russia Y.D. Chernousov ICKC, Novosibirsk, Russia V. Ivannikov, I.V. Shebolaev ICKC SB RAS, Novosibirsk, Russia
	Accelerating stand based on parallel coupled accelerating structure and electron gun is developed and produced. The structure consists of five accelerating cavities. The RF power feeding of accelerating cavities is provided by common exciting cavity which is performed from rectangular waveguide loaded by reactive pins. Operating frequency is 2450 MHz. Electron gun is made on the basis of RF triode. Linear accelerator was tested with different working regimes. The obtained results are following: energy is up to 4 MeV, accelerating current is up to 300 mA with pulse duration of 2.5 ns on the half of the width; energy is up to 2.5 MeV, accelerating current is up to 100 mA with pulse duration of 5 μs; energy is up to 2.5 MeV, accelerating current is up to 120 mA with pulse duration of 5 μs and beam capture of 100%. The descriptions of the accelerator elements are given in the report. The features of the parallel coupled accelerating structure are discussed. The results of the measuring accelerator’s parameters are presented.

SUPB012	Status of CH Cavity and Solenoid Design of the 17 MeV Injector for MYRRHA	solenoid, focusing, rfq, quadrupole	29
	D. Mäder, H. Klein, H. Podlech, U. Ratzinger, C. Zhang IAP, Frankfurt am Main, Germany
	Funding: This work has been supported by the EU (FP7 MAX contract number 269565) The multifunctional subcritical reactor MYRRHA (Multi-purpose hybrid research reactor for high-tech applications) will be an accelerator driven system (ADS) located in Mol (Belgium). The first accelerating section up to 17 MeV is operated at 176 MHz and consists of a 4-rod-RFQ followed by two room temperature CH cavities with integrated triplet lenses and four superconducting CH structures with intertank solenoids. Each room temperature CH cavity provides about 1 MV effective voltage gain using less than 30 kW of RF power. The superconducting resonators have been optimized for electric peak fields below 30 MV/m and magnetic peak fields below 30 mT. For save operation of the superconducting resonators the magnetic field of the intertank solenoids has to be well shielded towards the CH cavity walls. Different coil geometries have been compared to find the ideal solenoid layout.

SUPB013	The Beam Commissioning Plan of Injector II in C-ADS	rfq, proton, simulation, diagnostics	32
	Z.J. Wang, Y. He, H. Jia, C. Li, S.H. Liu, W. Wu, X.B. Xu, B. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	The design work of the Injector II, which is 10 MeV proton linac, in C-ADS project is being finished and some key elements are being fabricated. Now it is necessary to definite the operation mode of beam commissioning, including the selection of the beam current, pulse length and repetition frequency. Also the beam commissions plan should be specified. The beam commissions procedures is simulated with t-mode code GPT. In this paper, the general beam commissioning plan of Injector II in CIADS and simulation results of commissions procedures are presented.

SUPB015	Production and Quality Control of the First Modules of the IFMIF-EVEDA RFQ	survey, controls, coupling, rfq	38
	F. Scantamburlo, R. Dima, A. Pepato INFN- Sez. di Padova, Padova, Italy C. Roncolato INFN/LNL, Legnaro (PD), Italy
	The IFMIF-EVEDA RFQ, designed to accelerate a 125 mA D⁺ beam from the initial energy of 0.1 MeV to the final energy of 5 MeV at the frequency of 175 MHz, consists of 18 mechanical modules whose length is approximately 54 cm each. The production of the modules has started and, in particular, the modules 16, 17, 15 and 11, plus the prototype modules 1 and 2 have undergone all the production steps, including precision milling and brazing. In this article, the progress of the production, and the quality control during the phases of the production of the modules will be described.

SUPB018	Studies of Parasitic Cavity Modes for Proposed ESS Linac Lattices	linac, simulation, proton, lattice	47
	R. Ainsworth Royal Holloway, University of London, Surrey, United Kingdom S. Molloy ESS, Lund, Sweden
	The European Spallation Source (ESS) planned for construction in Lund, Sweden, will be the worlds most intense source of pulsed neutrons. The neutrons will be generated by the collision of a 2.5 GeV proton beam with a heavy-metal target. The superconducting section of the proton linac is split into three different types of cavities, and a question for the lattice designers is at which points in the beamline these splits should occur. This note studies various proposed designs for the ESS lattice from the point of view of the effect on the beam dynamics of the parasitic cavity modes lying close in frequency to the fundamental accelerating mode. Each linac design is characterised by the initial kinetic energy of the beam, as well as by the velocity of the beam at each of the points at which the cavity style changes. The scale of the phase-space disruption of the proton pulse is discussed, and some general conclusions for lattice designers are stated.

SUPB019	The Multipacting Simulation for the New-Shaped QWR using TRACK3P	simulation, accelerating-gradient, electron, niobium	50
	C. Zhang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, S.H. Zhang, S.X. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	In order to improve the electro-magnetic performance of the quarter wave resonator, a new-shaped cavity with an elliptical cylinder outer conductor has been proposed. This novel cavity design can provide much lower peak surface magnetic field and much higher Ra/Q0 and G. The Multipacting simulation has been done for this new QWR cavity using ACE3P/TRACK3P code, in this paper the simulation results will be presented and analyzed.

SUPB020	Structural Analysis of the New-Shaped QWR for HIAF in IMP	simulation, superconducting-cavity, SRF, controls	53
	C. Zhang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, Y.Z. Yang, W.M. Yue, S.H. Zhang, S.X. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China M.H. Xu IHEP, Beijing, People's Republic of China
	Since the QWR cavity is very successful for the operation with frequency of 48 to 160 MHz and beta value of 0.001 to 0.2, a new-shaped QWR is being designed for the low energy superconducting section of HIAF in the Institute of Modern Physics. The cavity will work at 81.25 MHz and \beta of 0.085，with a elliptical cylinder outer conductor to better its electro-magnetic performance and keep limited accelerating space. Structural design is an important aspect of the overall cavity implementation, and in order to minimize the frequency shift of the cavity due to the helium bath pressure fluctuations, the Lorentz force and microphonic excitation, stiffening elements have to be applied. In this paper, structural analyses of the new-shaped QWR are presented and stiffening methods are explored.

SUPB022	First Measurements on the 325 MHz Superconducting CH Cavity	simulation, controls, linac, coupling	56
	M. Busch, F.D. Dziuba, H. Podlech, U. Ratzinger IAP, Frankfurt am Main, Germany M. Amberg HIM, Mainz, Germany W.A. Barth, S. Mickat GSI, Darmstadt, Germany M. Pekeler RI Research Instruments GmbH, Bergisch Gladbach, Germany
	Funding: Work supported by HIM, GSI, BMBF Contr. No. 06FY161I At the Institute for Applied Physics (IAP), Frankfurt University, a superconducting 325 MHz CH-Cavity has been designed and built. This 7-cell cavity has a geometrical \beta of 0.16 corresponding to a beam energy of 11.4 AMeV. The design gradient is 5 MV/m. Novel features of this resonator are a compact design, low peak fields, easy surface processing and power coupling. Furthermore a new tuning system based on bellow tuners inside the resonator will control the frequency during operation. After successful rf tests in Frankfurt the cavity will be tested with a 10 mA, 11.4 AMeV beam delivered by the GSI UNILAC. In this paper first measurements and corresponding simulations will be presented.

SUPB023	Status of the Superconducting CW Demonstrator for GSI	linac, simulation, solenoid, cryogenics	59
	F.D. Dziuba, M. Amberg, M. Busch, H. Podlech, U. Ratzinger IAP, Frankfurt am Main, Germany K. Aulenbacher IKP, Mainz, Germany W.A. Barth, S. Mickat GSI, Darmstadt, Germany
	Funding: Helmholtz Institut Mainz (HIM), GSI, BMBF Contr. No. 06FY7102 Since the existing UNILAC at GSI will be used as an injector for the FAIR facility a new superconducting (sc) continous wave (cw) LINAC is highly requested by a broad community of future users to fulfil the requirements of nuclear chemistry, especially in the research field of Super Heavy Elements (SHE). This LINAC is under design in collaboration with the Institute for Applied Physics (IAP) of Frankfurt University, GSI and the Helmholtz Institut Mainz (HIM). It will consist of 9 sc Crossbar-H-mode (CH) cavities operated at 217 MHz which provide an energy up to 7.3 AMeV. Currently, a prototype of the cw LINAC is under development. This demonstrator comprises the first sc CH cavity of the LINAC embedded between two sc solenoids mounted in a horizontal cryomodule. One important milestone of the project will be a full performance test of the demonstrator by injecting and accelerating a beam from the GSI High Charge State Injector (HLI) in 2014. The status of the demonstrator is presented.

SUPB025	Development of Superconducting Radio-Frequency (SRF) Deflecting Mode Cavities and Associated Waveguide Dampers for the APS Upgrade Short Pulse X-Ray Project	HOM, photon, cryomodule, damping	65
	J.P. Holzbauer, A. Nassiri, G.J. Waldschmidt, G. Wu ANL, Argonne, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CHI1357. The Advanced Photon Source Upgrade (APS-U) is a Department of Energy (DoE) funded project to increase the available x-ray beam brightness and add capability to enhance time-resolved experiments on few-ps-scale at APS. A centerpiece of the upgrade is the generation of short pulse x-rays (SPXs) for pump-probe time-resolved capability using SRF deflecting cavities[1]. The SPX project is designed to produce 1-2 ps x-ray pulses for some users compared to the standard 100 ps pulses currently produced. SPX calls for using superconducting rf (SRF) deflecting cavities to give the electrons a correlation between longitudinal position in the bunch and vertical momentum [2]. The light produced by this bunch can be passed through a slit to produce a pulse of light much shorter than the bunch length at reduced flux. The ongoing work of designing these cavities and associated technologies will be presented. This includes the design and prototyping of higher-order (HOM) and lower-order mode (LOM) couplers and dampers as well as the fundamental power coupler (FPC). This work will be given in the context of SPX0, a demonstration cryomodule with two deflecting cavities to be installed in APS in early 2014. [1] A. Zholents, et al., NIM A 425, 385 (1999) [2] A. Nassiri, et al., “ Status of the Short-Pulse X-Ray Project at the Advanced Photon Source,” IPAC 2012, New Orleans, LA, May 2012.

SUPB026	Multipacting Analysis of High-velocity Superconducting Spoke Resonators	electron, site, simulation, superconductivity	68
	C.S. Hopper, J.R. Delayen ODU, Norfolk, Virginia, USA
	Some of the advantages of superconducting spoke cavities are currently being investigated for the high-velocity regime. When determining a final, optimized geometry, one must consider the possible limiting effects multipacting could have on the cavity. We report on the results of analytical calculations and numerical simulations of multipacting electrons in superconducting spoke cavities and methods for reducing their impact.

SUPB027	Mechanical Study of the First Superconducting Half-wave Resonator for Injector II of CADS Project	simulation, HOM, controls, cryomodule	71
	S. He, Y. He, S.C. Huang, F.F. Wang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	Funding: This work is Supported by the National Natural Science Foundation of China (Grant Agreement 91026001) Within the framework of the China Accelerator-Driven Sub-critical Systems (CADS) project, Institute of Modern Physics (IMP) Chinese Academic of Sciences has proposed a 162.5 MHz Half-Wave Resonator (HWR) Superconducting cavity for low energy section (β=0.09) of high power proton linear accelerators as a new injector II for CIADS. For the geometrical design of superconducting cavities structure mechanical simulations are essential to predict mechanical eigenmodes and the deformation of the cavity walls due to bath pressure effects and the cavity cool-down. Additionally, the tuning analysis has been investigated to control the frequency against microphonics and Lorentz force detuning. Therefore, several RF, static structure, thermal and modal analysis with a three-dimensional Finite-Element Method (FEM) code Traditional ANSYS have been performed.

SUPB028	The Superconducting CH Cavity Development in IMP*	simulation, linac, niobium, resonance	74
	M.X. Xu, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, Z.J. Wang, J.W. Xia, Y.Z. Yang, W.M. Yue, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	Funding: Work supported by 91026001 Nature Science Foundation of China The Cross-Bar H-type (CH) cavity is a multi-gap drift tube structure operated in the H21 mode [1]. The Institute of Modern Physics (IMP) has been doing research and development on this type of superconducting CH cavity which can work at the C-ADS (accelerator driver sub-critical system of China). A new geometry CH cavity has been proposed which have smaller radius. It’s suitable in fabrication, and it’s can reduce cost too .Detailed numerical simulations with CST MicroWave Studio have been performed. An overall surface reduction of 30% against the old structure seems feasible. A copper model CH cavity is being fabrication for validating the simulations and the procedure of fabricating niobium cavity.

SUPB029	Impact of Trapped Flux and Systematic Flux Expulsion in Superconducting Niobium	niobium, SRF, controls, superconductivity	77
	J.M. Vogt, J. Knobloch, O. Kugeler HZB, Berlin, Germany
	The intrinsic quality factor Q₀ of superconducting cavities is known to depend on various factors like niobium material properties, treatment history and magnetic shielding. We already reported an additional impact of temperature gradients during the cool-down on the obtained Q₀. We believe cooling conditions can influence the level of flux trapping and hence the residual resistance. For further studies we have constructed a test stand using niobium rods to study flux trapping. Here we can precisely control the temperature and approach T_c in the superconducting state. Although the sample remains in the superconducting state a change in the amount of trapped flux is visible. The procedure can be applied repeatedly resulting in a significantly lowered level of trapped flux in the sample. Applying a similar procedure to a superconducting cavity could allow for reduction of the magnetic contribution to the surface resistance and result in a significant improvement of Q₀.

SUPB032	The C-band RF Pulse Compression for Soft XFEL at SINAP	coupling, simulation, klystron, free-electron-laser	83
	C.P. Wang, Q. Gu, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	A compact soft X-ray free electron laser facility is presently being constructed at shanghai institute of applied physics (SINAP), Chinese academy of science in 2012 and will be accomplished in 2014. This facility requires a compact linac with a high-gradient accelerating structure for a limited overall length less than 230 m. The c-band technology which is already used in KEK/Spring-8 linear accelerator is a good compromise for this compact facility and a c-and traveling-wave accelerating structure was already fabricated and tested at SINAP, so a c-band pulse compression will be required. AND a SLED type RF compression scheme is proposed for the C-band RF system of the soft XFEL and this scheme uses TE0.1.15 mode energy storage cavity for high Q-energy storage. The C-band pulse compression under development at SINAP has a high power gain about 3.1 and it is designed to compress the pulse width from 2.5 μs to 0.5 μs and multiply the input RF power of 50 MW to generate 160 MW peak RF power, and the coupling coefficient will be 8.5. It has three components: 3 dB coupler, mode convertors and the resonant cavities.

SUPB038	Multipole Field Effects for the Superconducting Parallel-Bar Deflecting/Crabbing Cavities	dipole, multipole, superconductivity, luminosity	92
	S.U. De Silva, J.R. Delayen ODU, Norfolk, Virginia, USA S.U. De Silva JLAB, Newport News, Virginia, USA
	The superconducting parallel-bar deflecting/crabbing cavity is currently being considered as one of the design options in rf separation for the Jefferson Lab 12 GeV upgrade and for the crabbing cavity for the proposed LHC luminosity upgrade. Knowledge of multipole field effects is important for accurate beam dynamics study of rf structures. The multipole components can be accurately determined numerically using the electromagnetic surface field data in the rf structure. This paper discusses the detailed analysis of those components for the fundamental deflecting/crabbing mode and higher order modes in the parallel-bar deflecting/crabbing cavity.

SUPB039	Compact Superconducting Crabbing and Deflecting Cavities	dipole, HOM, damping, collider	95
	S.U. De Silva ODU, Norfolk, Virginia, USA S.U. De Silva JLAB, Newport News, Virginia, USA
	Recently, new geometries for superconducting crabbing and deflecting cavities have been developed that have significantly improved properties over those the standard TM110 cavities. They are smaller, have low surface fields, high shunt impedance and, more importantly for some of them, no lower-order-mode with a well-separated fundamental mode. This talk will present the status of the development of these cavities.

MO1A01	Operational Experience and Future Goals of the SARAF Linac at SOREQ	proton, target, linac, neutron	100
	D. Berkovits, A. Arenshtam, Y. Ben Aliz, Y. Buzaglo, O. Dudovich, Y. Eisen, I. Eliyahu, G. Feinberg, I. Fishman, I. Gavish, I.G. Gertz, A. Grin, S. Halfon, D. Har-Even, Y.F. Haruvy, T. Hirsch, D. Hirschmann, Z. Horvitz, B. Kaizer, D. Kijel, A. Kreisel, G. Lempert, J. Luner, I. Mardor, A. Perry, E. Reinfeld, J. Rodnizki, G. Shimel, A. Shor, I. Silverman, L. Weissman, E. Zemach Soreq NRC, Yavne, Israel
	SARAF-phase 1 at SOREQ, with its single 6 half-wave resonators cryomodule, is the first high current, superconducting low-beta linac in operation and it is presently delivering cw proton beams in the mA range. A phase 2 is foreseen for this linac which will allow acceleration up to 40 MeV of 2 mA cw proton and deuteron beams. The project status, the operational experience and the future goals of SARAF should be described.
	Slides MO1A01 [3.276 MB]

MO1A02	Status of the European XFEL – Constructing the 17.5 GeV Superconducting Linear Accelerator	undulator, electron, photon, klystron	105
	W. Decking DESY, Hamburg, Germany
	The European XFEL is presently under construction in Hamburg, Germany. It consists of a 1.2 km long superconducting linac serving an about 3 km long electron beam transport system. Three undulator systems of up to 200 m length each produce hard and soft x-rays via the self-amplified spontaneous emission (SASE) process. We will present the status of the civil construction and the accelerator components. The production of the 100 superconducting accelerator modules is distributed between industries and a collaboration of accelerator laboratories. We describe the carefully orchestrated production sequence, quality assurance measures and risk mitigation mechanisms. The last module is scheduled to be installed in the accelerator in spring 2015 and commissioning with beam will start in summer of that year.
	Slides MO1A02 [8.730 MB]

MO1A03	SRF Linac Technology Development at Fermilab	linac, SRF, cryogenics, status	110
	V.P. Yakovlev, C.M. Ginsburg Fermilab, Batavia, USA
	Superconducting linear accelerators are developing for different applications – for fundamental researches in High-Energy and High – Intensity Frontiers, nuclear physics, energetics, neutron spallation sources, synchrotron radiation sources, etc. The linac applications dictate the requirements for superconducting acceleration system, and, thus, for SRF technology. Fermilab is currently involved in two projects: ILC and Project X, both are based on SRF technology. For High-Intensity Frontier investigations, the Project X – a multi-experiment facility is developing based on 3 GeV, CW H⁻ linac in the frame of a wide collaboration of US National Laboratories. In a CW H⁻ linac several families of SC cavities are used: half-wave resonators (162.5 MHz); single-spoke cavities, SSR1 and SSR2 (325 MHz); elliptical 5-cell β=0.6 and β=0.9 cavities (650 MHz). Pulsed 3-8 GeV linac and ILC linac are based on 9-cell 1.3 GHz cavities. In the paper the basic requirements and the status of development of SC accelerating cavities, auxiliaries (couplers, tuners, etc.) and cryomodules are presented as well as technology challenges caused by their specifics.
	Slides MO1A03 [3.551 MB]

MO3A01	Development of H-mode Linacs for the FAIR Project	linac, DTL, proton, ion	120
	G. Clemente, W.A. Barth, L. Groening, S. Mickat, B. Schlitt, W. Vinzenz GSI, Darmstadt, Germany R. M. Brodhage, M. Busch, F.D. Dziuba, H. Podlech, U. Ratzinger IAP, Frankfurt am Main, Germany
	H-mode cavities offer outstanding shunt impedances at low beam energies and enable the acceleration of intense ion beams. Crossed-bar H-cavities extend these properties to energies even beyond 100 MeV. Thus, the designs of the new injector linacs for FAIR, i.e. a 70 MeV, 70 mA proton driver for pbar-production and a cw intermediate mass, superconducting ion linac are based on these novel cavities. Several prototypes (normal & super-conducting) have been built and successfully tested. Moreover, designs for a replacement of the 80 MV Alvarez section of the GSI - Unilac will be discussed to improve the capabilities as the future FAIR heavy ion injector.
	Slides MO3A01 [2.741 MB]

MO3A02	Commissioning of a New Injector for the RIKEN RI-Beam Factory	DTL, cyclotron, injection, rfq	125
	N. Sakamoto, M. Fujimaki, H. Hasebe, Y. Higurashi, O. Kamigaito, H. Okuno, K. Suda, T. Watanabe, K. Yamada RIKEN Nishina Center, Wako, Japan R. Koyama SHI Accelerator Service Ltd., Tokyo, Japan
	A new injector for the RIKEN RI-Beam Factory (RIBF) has been fully commissioned since October 2011. The injector accelerates ions of m/q=6.8 up to 670 keV/u. In order to save the cost and space, a direct coupling scheme was adopted for rf coupling between the cavity and amplifier, based on an elaborate design with the Microwave Studio code. It has worked out very stably in these three months, making the uranium beam intensity higher by one order of magnitude. Moreover, it is now possible to operate the RIBF and GARIS facility for the super-heavy element synthesis independently.
	Slides MO3A02 [19.503 MB]

MOPLB06	Fermilab 1.3 GHz Superconducting RF Cavity and Cryomodule Program for Future Linacs	cryomodule, status, linear-collider, linac	153
	C.M. Ginsburg Fermilab, Batavia, USA
	Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy. The proposed Project X accelerator and the International Linear Collider are based on superconducting RF technology. As a critical part of this effort, Fermilab has developed an extensive program in 1.3 GHz SRF cavity and cryomodule development. This program includes cavity inspection, surface processing, clean assembly, low-power bare cavity tests and pulsed high-power dressed cavity tests. Well performing cavities have been assembled into cryomodules for pulsed high-power tests and will be tested with beam. In addition, peripheral hardware such as tuners and couplers are under development. The current status and accomplishments of the Fermilab 1.3 GHz activity will be described, as well as the R&D program to extend the existing SRF pulsed operational experience into the CW regime.
	Slides MOPLB06 [1.508 MB]

MOPLB07	Non-destructive Inspections for SC Cavities	target, laser, SRF, cryogenics	156
	Y. Iwashita, Y. Fuwa, M. Hashida, K. Otani, S. Sakabe, S. Tokita, H. Tongu Kyoto ICR, Uji, Kyoto, Japan H. Hayano, K. Watanabe, Y. Yamamoto KEK, Ibaraki, Japan
	Non-destructive Inspections play important roles to improve yield in production of high-performance SC Cavities. Starting from the high-resolution camera for inspection of the cavity inner surface, high resolution T-map, X-map and eddy current scanner have been developed. We are also investigating radiography to detect small voids inside the Nb EBW seam, where the target resolution is 0.1 mm. We are carrying out radiography tests with X-rays induced from an ultra short pulse intense laser. Recent progress will be presented.
	Slides MOPLB07 [5.810 MB]

MOPLB08	Normal Conducting Deflecting Cavity Development at the Cockcroft Institute	beam-loading, wakefield, damping, electron	159
	G. Burt, P.K. Ambattu, A.C. Dexter, C. Lingwood, B.J. Woolley Cockcroft Institute, Lancaster University, Lancaster, United Kingdom S.R. Buckley, P. Goudket, C. Hill, P.A. McIntosh, J.W. McKenzie, A.E. Wheelhouse STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom V.A. Dolgashev SLAC, Menlo Park, California, USA A. Grudiev CERN, Geneva, Switzerland R.M. Jones UMAN, Manchester, United Kingdom
	Funding: This work has been supported by STFC and the EU through FP7 EUCARD. Two normal conducting deflecting structures are currently being developed at the Cockcroft Institute, one as a crab cavity for CLIC and one for bunch slice diagnostics on low energy electron beams for EBTF at Daresbury. Each has its own challenges that need overcome. For CLIC the phase and amplitude tolerances are very stringent and hence beamloading effects and wakefields must be minimised. Significant work has been undertook to understand the effect of the couplers on beamloading and the effect of the couplers on the wakefields. For EBTF the difficulty is avoiding the large beam offset caused by the cavities internal deflecting voltage at the low beam energy. Propotypes for both cavities have been manufactured and results will be presented.
	Slides MOPLB08 [1.572 MB]

MOPLB10	FRIB Technology Demonstration Cryomodule Test	cryomodule, SRF, resonance, solenoid	165
	J. Popielarski, E.C. Bernard, S. Bricker, S. Chouhan, C. Compton, A. Facco, A. Fila, L.L. Harle, M. Hodek, L. Hodges, S. Jones, M. Leitner, D. R. Miller, S.J. Miller, D. Morris, R. Oweiss, J.P. Ozelis, L. Popielarski, K. Saito, N.R. Usher, J. Weisend, Y. Zhang, S. Zhao, Z. Zheng FRIB, East Lansing, USA M. Klaus Technische Universität Dresden, Dresden, Germany
	A Technology Demonstration Cryomodule (TDCM) has been developed for a systems test of technology being developed for FRIB. The TDCM consists of two half wave resonators (HWRs) which have been designed for an optimum velocity of β=v/c=0.53 and a resonant frequency of 322 MHz. The resonators operate at 2 K. A superconducting 9 T solenoid is placed in close proximity to one of the installed HWRs. The 9 T solenoid operates at 4 K. A complete systems test of the cavities, magnets, and all ancillary components is presented in this paper. This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE SC0000661.
	Slides MOPLB10 [2.530 MB]

MOPB004	Design and Operation of a Compact 1 MeV X-band Linac	linac, electron, gun, target	183
	G. Burt, T.N. Abram, P.K. Ambattu, C. Lingwood Cockcroft Institute, Lancaster University, Lancaster, United Kingdom I. Burrows, T. Hartnett, J.P. Hindley, C.J. White STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom P.A. Corlett, A.R. Goulden, P.A. McIntosh, K.J. Middleman, Y.M. Saveliev, R.J. Smith STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	A compact 1 MeV linac has been produced at the Cockcroft Institute using X-band RF technology. The linac is powered by a high power X-band magnetron and has a 17 keV 200 mA thermionic gun with a focus electrode for pulsing. A bi-periodic structure with on-axis coupling is used to minimise the radial size of the linac and to reduce the surface electric fields.

MOPB011	Photoinjector of the EBTF/CLARA Facility at Daresbury	gun, laser, vacuum, electron	192
	B.L. Militsyn, D. Angal-Kalinin, C. Hill, S.P. Jamison, J.K. Jones, J.W. McKenzie, K.J. Middleman, B.J.A. Shepherd, R.J. Smith, R. Valizadeh, A.E. Wheelhouse STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom N. Bliss, M.D. Roper STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
	A description is given of a photoinjector designed for Compact Linear Advanced Research Accelerator (CLARA) and Electron Beam Test Facility (EBTF), which will eventually be used to drive a compact FEL. The photoinjector is based on a 2.5 cell S-band photocathode RF gun operating with a copper photocathode and driven by a third harmonic of Ti: Sapphire laser (266 nm) installed in dedicated thermally stabilized room. The injector will be operated with laser pulses with an energy of up to 2 mJ, a pulse duration of 100 fs and initially a repetition rate of 10 Hz, with the aim of increasing this eventually to 400 Hz. At a field gradient of 100 MV/m provided by a 10 MW klystron the gun is expected to deliver beam pulses with energy of up to 6 MeV. Duration and emittance of electron bunches essentially depend on the bunch charge and vary from 0.1 ps at 20 pC to 5 ps at 200 pC and from 0.2 to 2 mm mrad respectively. Additional compression of the electron bunches will be provided with a velocity bunching scheme. For thermal stability the low energy part of the injector is mounted on an artificial granite support.

MOPB012	First RF Measurement Results for the European XFEL SC Cavity Production	HOM, controls, factory, higher-order-mode	195
	A.A. Sulimov, P.B. Borowiec, V. Gubarev, J. Iversen, D. Kostin, G. Kreps, K. Krzysik, A. Matheisen, W.-D. Möller, D. Reschke, W. Singer DESY, Hamburg, Germany
	The first reference cavities (RCV) for the European XFEL Project are being tested within the collaboration of Research Instruments (RI), E. ZANON, IFJ-PAN and DESY: - production and warm RF measurements of cavities and their components at RI and ZANON; - surface preparation at DESY; - cold RF tests at DESY by IFJ-PAN. Purpose of the RCV is to establish a stable cavity fabrication and qualification of the surface preparation infrastructure at industry. All necessary RF measurements were done, starting with mechanical fabrication in 2011, till the tuning and cold cavity RF tests in 2012. We present the first results of RF measurements within RCV production for the European XFEL.
	Poster MOPB012 [1.843 MB]

MOPB017	Integration of the European XFEL Accelerating Modules	controls, linac, vacuum, HOM	207
	E. Vogel, S. Barbanotti, J. Branlard, H. Brueck, S. Choroba, L. Hagge, K. Jensch, V.V. Katalev, D. Kostin, D. Käfer, L. Lilje, A. Matheisen, W.-D. Möller, D. Nölle, B. Petersen, J. Prenting, D. Reschke, H. Schlarb, M. Schmökel, J.K. Sekutowicz, W. Singer, H. Weise DESY, Hamburg, Germany J. Świerbleski, P.B. Borowiec IFJ-PAN, Kraków, Poland S. Berry, O. Napoly, B. Visentin CEA/DSM/IRFU, France A. Bosotti, P. Michelato INFN/LASA, Segrate (MI), Italy W. Kaabi LAL, Orsay, France C. Madec CEA/IRFU, Gif-sur-Yvette, France E.P. Plawski NCBJ, Świerk/Otwock, Poland F. Toral CIEMAT, Madrid, Spain
	The production of the 103 superconducting accelerating modules for the European XFEL is an international effort. Institutes and companies from seven different countries (China, France, Germany, Italy, Poland, Russia and Spain), organized in 12 different work packages contribute with parts, capacity for work and facilities to the production of the modules. Currently the series production of the individual parts started or is approaching. Personnel are trained for the assembly and testing of parts and as well for the complete modules. Here we present an overview and the status of all these activities.

MOPB025	1ms Multi-bunch Electron Beam Acceleration by a Normal Conducting RF Gun and Superconducting Accelerator	gun, laser, emittance, cathode	228
	M. Kuriki, S. Hosoda, H. Iijima HU/AdSM, Higashi-Hiroshima, Japan H. Hayano, J. Urakawa, K. Watanabe KEK, Ibaraki, Japan G. Isoyama, R. Kato, K. Kawase ISIR, Osaka, Japan S. Kashiwagi Tohoku University, Research Center for Electron Photon Science, Sendai, Japan A. Kuramoto Sokendai, Ibaraki, Japan K. Sakaue RISE, Tokyo, Japan
	Funding: Quantum Beam Project by MEXT, Japan We perform electron beam generation and acceleration of 1 ms long pulse and multi-bunch format at KEK-STF (Superconducting Test Facility). The 1 ms long pulse beam is generated by a normal conducting photo-cathode L-band RF gun. The beam is boosted up to 40 MeV by a super-conducting accelerator. Aim of STF is to establish the super-conducting accelerator technology for ILC (International Linear Collider). The facility is concurrently used to demonstrate high brightness X-ray generation by inverse laser Compton scattering supported by MEXT Quantum Beam project. The RF gun cavity has been fabricated by DESY-FNAL-KEK collaboration. After conditioning process, a stable operation of the cavity up to 4.0 MW RF input with 1 ms pulse was achieved by keeping low dark current. 1 ms pulse generation and acceleration has been confirmed in March 2012. Quasi-monochromatic X-ray generation experiment by Laser-Compton will be carried out at STF from the next coming July. We report the latest status of STF.

MOPB026	TRIUMF/VECC e-Linac Injector Beam Test	diagnostics, linac, gun, cryomodule	231
	R.E. Laxdal, F. Ames, Y.-C. Chao, K. Fong, C. Gong, A. Laxdal, M. Marchetto, W.R. Rawnsley, S. Saminathan, V.A. Verzilov, Q. Zheng, V. Zvyagintsev TRIUMF, Vancouver, Canada J.M. Abernathy, D. Karlen, D.W. Storey Victoria University, Victoria, B.C., Canada A. Chakrabarti, V. Naik VECC, Kolkata, India
	TRIUMF is collaborating with VECC on the design of a 10 MeV injector cryomodule to be used as a front end for a high intensity electron linac. A electron gun and low energy beam transport (LEBT) have been installed in a test area to act as the injector for the cryomodule test. The LEBT includes a wide variety of diagnostics to fully characterize the beam from the gun. A series of beam tests are being conducted during the stage installation. The test configuration details and results of beam tests will be presented.

MOPB030	Performance of First C100 Cryomodules for the CEBAF 12 GeV Upgrade Project	cryomodule, linac, vacuum, instrumentation	237
	M.A. Drury, A. Burrill, G.K. Davis, J. Hogan, L.K. King, F. Marhauser, H. Park, J.P. Preble, C.E. Reece, A.V. Reilly, R.A. Rimmer, H. Wang, M. Wiseman JLAB, Newport News, Virginia, USA
	Funding: This manuscript has been authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The Thomas Jefferson National Accelerator Facility is currently engaged in the 12 GeV Upgrade Project. The goal of the project is a doubling of the available beam energy of CEBAF from 6 GeV to 12 GeV. This increase in beam energy will be due primarily to the construction and installation of ten “C100” cryomodules in the CEBAF linacs. The C100 cryomodules are designed to deliver an average 108 MV each from a string of eight seven-cell, electropolished superconducting RF cavities operating at an average accelerating gradient of 19.2 MV/m. The new cryomodules fit in the same available linac space as the original CEBAF 20 MV cryomodules. Cryomodule production started in September 2010. Initial acceptance testing started in June 2011. The first two C100 cryomodules were installed and tested from August 2011 through October 2011, and successfully operated during the last period of the CEBAF 6 GeV era, which ended in May 2012. This paper will present the results of acceptance testing and commissioning of the C100 style cryomodules to date.

MOPB031	Vibration Response Testing of the CEBAF 12 GeV Upgrade Cryomodules	cryomodule, damping, controls, beam-loading	240
	G.K. Davis, J. Matalevich, T. Powers, M. Wiseman JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177 The CEBAF 12 GeV upgrade project includes 80 new 7-cell cavities assembled into 10 cryomodules. These cryomodules were tested during production to characterize their microphonic response in situ. For several early cryomodules, detailed (vibration) modal studies of the cryomodule string were performed during the assembly process to identify the structural contributors to the measured cryomodule microphonic response. Structural modifications were then modeled, implemented, and verified by subsequent modal testing and in-situ microphonic response testing. Interim and final results from this multi-stage process will be reviewed.

MOPB035	The Linear Accelerating Structure Development for HLS Upgrade	linac, electron, injection, bunching	252
	K. Jin, Y. Hong, G. Huang, D. Jia, S.C. Zhang USTC/NSRL, Hefei, Anhui, People's Republic of China
	Hefei Light Source (HLS) is mainly composed of an 800 MeV electron storage ring and a 200 MeV constant-impedance Linac functioning as its injector. A new Linac is developed in view of the Full Energy Injection and the Top-up Injection scheme will be adopted in the HLS upgrade. In this paper, an 800 MeV linear accelerating system construction, the constant-gradient structure design and the symmetry couplers consideration will be described in detail. The manufacture technology, the RF measurement, the high power test results and the accelerating system operation are presented.

MOPB037	Linac Optics Design for Multi-turn ERL Light Source	linac, optics, acceleration, cryomodule	258
	Y. Petenev, T. Atkinson, A.V. Bondarenko, A.N. Matveenko HZB, Berlin, Germany
	The optics simulation group at HZB is designing a multi-turn energy recovery linac-based light source. Using the superconducting Linac technology, the Femto-Science-Factory (FSF) will provide its users with ultra-bright photon beams of angstrom wavelength at 6 GeV. The FSF is intended to be a multi-user facility and offer a variety of operation modes. In this paper a design of transverse optic of the beam motion in the Linacs is presented. An important point in the optics design was minimization of the beta-functions in the linac at all beam passes to suppress beam break-up (BBU) instability.

MOPB048	Linear Accelerator Based on Parallel Coupled Accelerating Structure	electron, controls, focusing, klystron	282
	A.E. Levichev, A.M. Barnyakov, V.M. Pavlov BINP SB RAS, Novosibirsk, Russia Y.D. Chernousov ICKC, Novosibirsk, Russia V. Ivannikov, I.V. Shebolaev ICKC SB RAS, Novosibirsk, Russia
	Accelerating stand based on parallel coupled accelerating structure and electron gun is developed and produced. The structure consists of five accelerating cavities. The RF power feeding of accelerating cavities is provided by common exciting cavity which is performed from rectangular waveguide loaded by reactive pins. Operating frequency is 2450 MHz. Electron gun is made on the basis of RF triode. Linear accelerator was tested with different working regimes. The obtained results are following: energy is up to 4 MeV, accelerating current is up to 300 mA with pulse duration of 2.5 ns on the half of the width; energy is up to 2.5 MeV, accelerating current is up to 100 mA with pulse duration of 5 μs; energy is up to 2.5 MeV, accelerating current is up to 120 mA with pulse duration of 5 μs and beam capture of 100%. The descriptions of the accelerator elements are given in the report. The features of the parallel coupled accelerating structure are discussed. The results of the measuring accelerator’s parameters are presented.

MOPB049	Design of Compact C-Band Standing-Wave Accelerator for Medical Radiotherapy	electron, coupling, bunching, focusing	285
	H. Yang, M.-H. Cho, W. Namkung POSTECH, Pohang, Kyungbuk, Republic of Korea S.H. Kim ANL, Argonne, USA J.-S. Oh NFRI, Daejon, Republic of Korea
	Funding: Work supported by POSTECH Physics BK21 Program. We design a C-band standing-wave accelerator for an X-ray and electron source of medical radiotherapy. The accelerator system is operated two modes, using the X-ray and electron beams. Since two modes require different energy, the accelerator is capable of producing 6-MeV, 100-mA pulsed electron beams with peak 2-MW RF power, and 7.5-MeV, 50 mA electron beams with peak 2.5-MW RF power. The beam is focused by less than 1 mm without external magnets. The accelerating structure is a bi-periodic and on-axis-coupled structure with a built-in bunching section, which consists of 3 bunching cells, 14 normal cells and a coupling cell. It is operated with the π/2-mode standing-wave. The bunching cells are designed to enhance the RF phase focusing. Each cavity is designed by the MWS code within 3% inter-cell coupling. In this paper, we present design details of RF cavities and the beam dynamics.

MOPB052	Fermilab 1.3 GHz Superconducting RF Cavity and Cryomodule Program for Future Linacs	cryomodule, status, linear-collider, linac	291
	C.M. Ginsburg Fermilab, Batavia, USA
	Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy. The proposed Project X accelerator and the International Linear Collider are based on superconducting RF technology. As a critical part of this effort, Fermilab has developed an extensive program in 1.3 GHz SRF cavity and cryomodule development. This program includes cavity inspection, surface processing, clean assembly, low-power bare cavity tests and pulsed high-power dressed cavity tests. Well performing cavities have been assembled into cryomodules for pulsed high-power tests and will be tested with beam. In addition, peripheral hardware such as tuners and couplers are under development. The current status and accomplishments of the Fermilab 1.3 GHz activity will be described, as well as the R&D program to extend the existing SRF pulsed operational experience into the CW regime.

MOPB053	Non-destructive Inspections for SC Cavities	target, laser, SRF, cryogenics	294
	Y. Iwashita, Y. Fuwa, M. Hashida, K. Otani, S. Sakabe, S. Tokita, H. Tongu Kyoto ICR, Uji, Kyoto, Japan H. Hayano, K. Watanabe, Y. Yamamoto KEK, Ibaraki, Japan
	Non-destructive Inspections play important roles to improve yield in production of high-performance SC Cavities. Starting from the high-resolution camera for inspection of the cavity inner surface, high resolution T-map, X-map and eddy current scanner have been developed. We are also investigating radiography to detect small voids inside the Nb EBW seam, where the target resolution is 0.1 mm. We are carrying out radiography tests with X-rays induced from an ultra short pulse intense laser. Recent progress will be presented.

MOPB054	Test Results of Tesla-style Cryomodules at Fermilab	cryomodule, SRF, controls, LLRF	297
	E.R. Harms, K. Carlson, B. Chase, D.J. Crawford, E. Cullerton, D.R. Edstrom, Jr, A. Hocker, M.J. Kucera, J.R. Leibfritz, O.A. Nezhevenko, D.J. Nicklaus, Y.M. Pischalnikov, P.S. Prieto, J. Reid, W. Schappert, P. Varghese Fermilab, Batavia, USA
	Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy. Commissioning and operation of the first Tesla-style Cryomodule (CM-1) at Fermilab was concluded in recent months. It has now been replaced by a second Tesla Type III+ module, RFCA002. It is the first 8-cavity ILC style cryomodule to be built at Fermilab and also the first accelerating cryomodule of the Advanced Superconducting Test Accelerator (ASTA). We report on the operating results of both of these cryomodules.

MOPB055	Development of Superconducting Radio-Frequency (SRF) Deflecting Mode Cavities and Associated Waveguide Dampers for the APS Upgrade Short Pulse X-Ray Project	HOM, photon, cryomodule, damping	300
	J.P. Holzbauer, A. Nassiri, G.J. Waldschmidt, G. Wu ANL, Argonne, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CHI1357. The Advanced Photon Source Upgrade (APS-U) is a Department of Energy (DoE) funded project to increase the available x-ray beam brightness and add capability to enhance time-resolved experiments on few-ps-scale at APS. A centerpiece of the upgrade is the generation of short pulse x-rays (SPXs) for pump-probe time-resolved capability using SRF deflecting cavities[1]. The SPX project is designed to produce 1-2 ps x-ray pulses for some users compared to the standard 100 ps pulses currently produced. SPX calls for using superconducting rf (SRF) deflecting cavities to give the electrons a correlation between longitudinal position in the bunch and vertical momentum [2]. The light produced by this bunch can be passed through a slit to produce a pulse of light much shorter than the bunch length at reduced flux. The ongoing work of designing these cavities and associated technologies will be presented. This includes the design and prototyping of higher-order (HOM) and lower-order mode (LOM) couplers and dampers as well as the fundamental power coupler (FPC). This work will be given in the context of SPX0, a demonstration cryomodule with two deflecting cavities to be installed in APS in early 2014. [1] A. Zholents, et al., NIM A 425, 385 (1999) [2] A. Nassiri, et al., “ Status of the Short-Pulse X-Ray Project at the Advanced Photon Source,” IPAC 2012, New Orleans, LA, May 2012.

MOPB056	Multipacting Analysis of High-Velocity Superconducting Spoke Resonators	electron, site, simulation, superconductivity	303
	C.S. Hopper, J.R. Delayen ODU, Norfolk, Virginia, USA
	Some of the advantages of superconducting spoke cavities are currently being investigated for the high-velocity regime. When determining a final, optimized geometry, one must consider the possible limiting effects multipacting could have on the cavity. We report on the results of analytical calculations and numerical simulations of multipacting electrons in superconducting spoke cavities and methods for reducing their impact.

MOPB057	Mechanical Study of the First Superconducting Half-wave Resonator for Injector II of CADS Project	simulation, HOM, controls, cryomodule	306
	S. He, Y. He, S.C. Huang, F.F. Wang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	Funding: This work is Supported by the National Natural Science Foundation of China (Grant Agreement 91026001) Within the framework of the China Accelerator-Driven Sub-critical Systems (CADS) project, Institute of Modern Physics (IMP) Chinese Academic of Sciences has proposed a 162.5 MHz Half-Wave Resonator (HWR) Superconducting cavity for low energy section (β=0.09) of high power proton linear accelerators as a new injector II for CIADS. For the geometrical design of superconducting cavities structure mechanical simulations are essential to predict mechanical eigenmodes and the deformation of the cavity walls due to bath pressure effects and the cavity cool-down. Additionally, the tuning analysis has been investigated to control the frequency against microphonics and Lorentz force detuning. Therefore, several RF, static structure, thermal and modal analysis with a three-dimensional Finite-Element Method (FEM) code Traditional ANSYS have been performed.

MOPB059	The Superconducting CH Cavity Development in IMP*	simulation, linac, niobium, resonance	309
	M.X. Xu, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, Z.J. Wang, J.W. Xia, Y.Z. Yang, W.M. Yue, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	Funding: Work supported by 91026001 Nature Science Foundation of China The Cross-Bar H-type (CH) cavity is a multi-gap drift tube structure operated in the H21 mode [1]. The Institute of Modern Physics (IMP) has been doing research and development on this type of superconducting CH cavity which can work at the C-ADS (accelerator driver sub-critical system of China). A new geometry CH cavity has been proposed which have smaller radius. It’s suitable in fabrication, and it’s can reduce cost too .Detailed numerical simulations with CST MicroWave Studio have been performed. An overall surface reduction of 30% against the old structure seems feasible. A copper model CH cavity is being fabrication for validating the simulations and the procedure of fabricating niobium cavity.

MOPB060	RF Surface Impedance Characterization of Potential New Materials for SRF-based Accelerators	niobium, SRF, impedance, superconductivity	312
	B. P. Xiao, G.V. Eremeev, H.L. Phillips, C.E. Reece JLAB, Newport News, Virginia, USA M.J. Kelley, B. P. Xiao The College of William and Mary, Williamsburg, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. In the development of new superconducting materials for possible use in SRF-based accelerators, it is useful to work with small candidate samples rather than complete resonant cavities. The recently commissioned Jefferson Lab rf Surface Impedance Characterization (SIC) system* can presently characterize the central region of 50 mm diameter disk samples of various materials from 2 to 40 K exposed to RF magnetic fields up to 14 mT at 7.4 GHz. We report the measurement results from bulk Nb, thin film Nb on Cu and sapphire substrates, and thin film MgB₂ on sapphire substrate provided by colleagues at JLab and Temple University. We also report on efforts to extend the operating range to higher fields. * B.P. Xiao, et al., RSI, 2011. 82: p. 056104

MOPB061	The New 2nd Generation SRF R&D Facility at Jefferson Lab: TEDF	SRF, cryomodule, cryogenics, electron	315
	C.E. Reece, A.V. Reilly JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The US Department of Energy has funded a near-complete renovation of the SRF-based accelerator research and development facilities at Jefferson Lab. The project to accomplish this, the Technical and Engineering Development Facility (TEDF) Project has completed the first of two phases. An entirely new 3,300 m² purpose-built SRF technical work facility has been constructed and is being occupied in summer of 2012. All SRF work processes with the exception of cryogenic testing has been relocated into the new building. All cavity fabrication, processing, thermal treatment, chemistry, cleaning, and assembly work is collected conveniently into a new LEED-certified building. An innovatively designed 750 m² cleanroom/chemrooms suite provides long-term flexibility for support of multiple R&D and construction projects as well as continued process evolution. The detailed characteristics of this perhaps first 2nd-generation SRF facility will be described.

MOPB062	A New Internal Optical Profilometry System for Characterization of RF Cavity Surfaces – CYCLOPS	controls, ion, feedback, acceleration	318
	C.E. Reece, A.D. Palczewski, H. Tian JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Jefferson Lab has received and commissioned a new interferometric optical profilometer specifically designed to provide internal surface mapping of elliptical rf cavities. The CavitY CaLibrated Optical Profilometry System – CYCLOPS – provides better than 2 micron lateral resolution and 0.1 micron surface height resolution of programmatically selected locations on the interior surface of multi-cell cavities. The system is being used to provide detailed characterization of surface topographic evolution as a function of applied surface treatments and to investigate particular localized defects. We also intend to use the system for 3D mapping of actual interior rf surface geometry for feedback to structure design model and fabrication tooling. First uses will be illustrated. CYCLOPS was developed and fabricated by MicroDynamics Inc., Woodstock, GA, USA.

MOPB063	Superconducting RF Linac for eRHIC	linac, SRF, HOM, electron	321
	S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, H. Hahn, D. Kayran, V. Litvinenko, G.J. Mahler, G.T. McIntyre, V. Ptitsyn, R. Than, J.E. Tuozzolo, W. Xu, A. Zaltsman BNL, Upton, Long Island, New York, USA S.A. Belomestnykh Stony Brook University, Stony Brook, USA
	Funding: Work is supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. DOE. eRHIC will collide high-intensity hadron beams from RHIC with 50-mA electron beam from a six-pass 30-GeV Energy Recovery Linac (ERL), which will utilize 704 MHz superconducting RF accelerating structures. This presentation describes the eRHIC SRF linac requirements, layout and parameters, 5-cell SRF cavity with a new HOM damping scheme, project status and plans.

MOPB064	Developing of Superconducting RF Guns at BNL	gun, SRF, cathode, electron	324
	S.A. Belomestnykh, Z. Altinbas, I. Ben-Zvi, J.C. Brutus, D.M. Gassner, H. Hahn, L.R. Hammons, J.P. Jamilkowski, D. Kayran, J. Kewisch, V. Litvinenko, G.J. Mahler, G.T. McIntyre, D. Pate, D. Phillips, T. Rao, S.K. Seberg, T. Seda, B. Sheehy, J. Skaritka, K.S. Smith, R. Than, J.E. Tuozzolo, E. Wang, Q. Wu, W. Xu, A. Zaltsman BNL, Upton, Long Island, New York, USA S.A. Belomestnykh, J. Dai, M. Ruiz-Osés, T. Xin Stony Brook University, Stony Brook, USA C.H. Boulware, T.L. Grimm Niowave, Inc., Lansing, Michigan, USA A. Burrill JLAB, Newport News, Virginia, USA R. Calaga CERN, Geneva, Switzerland M.D. Cole, A.J. Favale, D. Holmes, J. Rathke, T. Schultheiss, A.M.M. Todd AES, Medford, NY, USA X. Liang SBU, Stony Brook, New York, USA
	Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE. The work at Niowave is supported by the US DOE under SBIR contract No. DE-FG02-07ER84861. BNL is developing several superconducting RF guns for different applications. The first gun is based on a half-cell 1.3 GHz elliptical cavity. This gun is used to study generation of polarized electrons from GaAs photocathodes. The second gun, also of a half-cell elliptical cavity design, operates at 704 MHz and is designed to produce high average current electron beam for the ERL prototype from a multi-alkali photocathodes. The third gun is of a quarter-wave resonator type, operating at 112 MHz. This gun will be used for photocathode studies, including a diamond-amplified cathode, and to generate high charge, low repetition rate beam for the coherent electron cooling experiment. In this presentation we will briefly describe the gun designs, present recent test results and discuss future plans.

MOPB065	Impact of Trapped Magnetic Flux and Systematic Flux Expulsion in Superconducting Niobium	niobium, SRF, controls, superconductivity	327
	J.M. Vogt, J. Knobloch, O. Kugeler HZB, Berlin, Germany
	The intrinsic quality factor Q₀ of superconducting cavities is known to depend on various factors like niobium material properties, treatment history and magnetic shielding. We already reported an additional impact of temperature gradients during the cool-down on the obtained Q₀. We believe cooling conditions can influence the level of flux trapping and hence the residual resistance. For further studies we have constructed a test stand using niobium rods to study flux trapping. Here we can precisely control the temperature and approach T_c in the superconducting state. Although the sample remains in the superconducting state a change in the amount of trapped flux is visible. The procedure can be applied repeatedly resulting in a significantly lowered level of trapped flux in the sample. Applying a similar procedure to a superconducting cavity could allow for reduction of the magnetic contribution to the surface resistance and result in a significant improvement of Q₀.

MOPB066	Alternative Approaches for HOM-Damped Cavities	multipole, acceleration, HOM, linac	330
	B. Riemann, T. Weis DELTA, Dortmund, Germany A. Neumann HZB, Berlin, Germany
	Funding: this work is partly funded by BMBF contract no. 05K10PEA Elliptical cavities have been a standard in SRF linac technology for 30 years. We present another approach to base cell geometry based on Bezier splines, that leads to equal performance levels and is much more flexible in terms of optimization. Using the BERLinPro main linac as an example, a spline multicell cavity is designed with equal performance goals. For the damping of higher order modes (HOMs), the installation of waveguides at the ends of a multicell cavity is a common approach.

MOPB067	Results and Performance Simulations of the Main Linac Design for BERLinPro	HOM, linac, quadrupole, dipole	333
	A. Neumann, W. Anders, J. Knobloch HZB, Berlin, Germany K. Brackebusch, T. Flisgen, T. Galek, K. Papke, U. van Rienen Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany B. Riemann, T. Weis DELTA, Dortmund, Germany
	Funding: this work is partly funded by BMBF contract no. 05K10PEA and 05K10HRC The Berlin Energy Recovery Linac Project (BERLinPro) is designed to develop and demonstrate CW LINAC technology for 100-mA-class ERLs. High-current operation requires an effective damping of higher-order modes (HOMs) of the 1.3 GHz main-linac cavities. We have studied elliptical 7-cell cavities damped by on the whole five waveguides at both ends. Eigenmode computations for geometrical figures of merit show that the present design should allow successful CW linac operation at the maximum beam current of 100 mA/77 pC bunch charge. To verify the results, the external Q factors are compared to the results of S-Parameter simulations that are postprocessed by a pole-fitting technique. First results of scattering parameter measurement on a room-temperature aluminium model are discussed. An outlook presenting the possibilities of combined multi-cavity simulations is included.

MOPB069	Study of HPR Created Oxide Layer at Nb Surfaces	SRF, vacuum, electron, ion	336
	P.V. Tyagi Sokendai, Ibaraki, Japan H. Hayano, S. Kato, T. Saeki, M. Sawabe KEK, Ibaraki, Japan
	The performance of superconducting radio frequency (SRF) niobium (Nb) cavities strongly depends on final surface condition. Therefore the surface preparation of these SRF cavities often becomes critical. The preparation of surface includes two steps; surface chemistry (in order to get a smooth surface) and cleaning/rinsing (in order to remove contaminants left after the surface chemistry). As high pressure rinsing (HPR) with ultra pure water (UPW) is most commonly used surface cleaning method after the surface chemistry, it's very interesting to characterize the Nb surfaces after HPR. Results of our surface characterization done by XPS (x-ray photoelectron spectroscopy) with depth profiling show the presence of a thicker oxide surface characterization results show the presence of a thicker oxide layer at Nb surface as an outcome of HPR. In this article, we report the production of oxide layer (FWHM thickness) based on different conditions such as the pressures and doses.

MOPB070	Quality Control of Cleanroom Processing Procedures of SRF Cavities for Mass Production	controls, SRF, acceleration, diagnostics	339
	R. Oweiss, K. Elliott, A. Facco, M. Hodek, I.M. Malloch, J. Popielarski, L. Popielarski, K. Saito FRIB, East Lansing, Michigan, USA
	Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661. Quality control is a key factor in the success of SRF cavity mass production. This paper summarizes ongoing research at the Facility for Rare Isotope Beams FRIB to validate the quality assurance of SRF cavities meanwhile optimizing processing procedures for mass production. Experiments are conducted to correlate surface cleanliness for niobium surfaces with high pressure rinse time using β=0.085 quarter-wave resonators (QWR) cavities. Diagnostic devices; liquid particle counter, surface particle detector and TOC analyzer are used to monitor key parameters for quality control. Rinse water samples are collected during high pressure rinsing to measure liquid particle counts. The SLS 1200 Sampler is used to detect the presence of liquid particles of 0.2 microns and up to 1 micron to set standards for acceptable cleaning thresholds and optimize high pressure rinse time. The QIII+ surface particle detector is used to scan high electric field region for the β=0.085 QWR to ensure high pressure rinsing efficiency. The β=0.085 QWR RF testing data are analyzed and results are presented to demonstrate the correlation between attained acceleration gradients and surface cleanliness.

MOPB071	Process Developments for Superconducting RF Low Beta Resonators for the ReA3 LINAC and Facility for Rare Isotope Beams	vacuum, controls, SRF, linac	342
	L. Popielarski, C. Compton, L.J. Dubbs, K. Elliott, A. Facco, L.L. Harle, I.M. Malloch, R. Oweiss, J.P. Ozelis, J. Popielarski, K. Saito 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 Facility for Rare Isotope Beams (FRIB) will utilize over 330 superconducting radio frequency (SRF) low beta cavities for its heavy ion driver linac. The SRF department will process and test all cavities prior to string assembly in the cleanroom. The baseline cavity surface and bulk niobium processing procedures have been established. The methods are being optimized for production process rate benchmarking. Additional processes are being developed to increase flexibility and reduce technical risks. This paper will describe procedure developments and experimental results. Topics include high temperature heat treatment for hydrogen degassing, selective chemical etching for cavity frequency tuning, low-temperature bake out and process quality control.

MOPB072	Multipole Expansion of the Fields in Superconducting High-Velocity Spoke Cavities	multipole, quadrupole, linac, simulation	345
	R.G. Olave, J.R. Delayen, C.S. Hopper ODU, Norfolk, Virginia, USA
	Multi-spokes superconducting cavities in the high-beta regime are being considered for a number of applications. In order to accurately model the dynamics of the particles in such cavities, knowledge of the fields off-axis are needed. We present a study of the multipoles expansion of the fields from an EM simulation field data for a two-spoke cavity operating at 325 MHz, β = 0.82 and 500 MHz, β = 1.

MOPB073	Cold Testing of Superconducting 72 MHz Quarter-wave Cavities for ATLAS	cryomodule, niobium, linac, accelerating-gradient	348
	M.P. Kelly, Z.A. Conway, S.M. Gerbick, M. Kedzie, R.C. Murphy, P.N. Ostroumov, T. Reid ANL, Argonne, USA
	A set of seven 72 MHz β=0.077 superconducting quarter-wave cavities for a beam intensity upgrade of the ATLAS heavy-ion accelerator has been completed. Cavities have been fabricated using the lessons learned from the worldwide effort to extend the performance of niobium cavities close to the limits of the material. Key developments include the use of electropolishing on the completed cavity and with a temperature control system substantially upgraded from that for elliptical-cell EP systems. Wire EDM, used instead of traditional niobium machining, appears to be effective in eliminating performance limiting defects near the weld seams. Hydrogen degassing at 600C after electropolishing permits practical acceleration at 2 Kelvin with Bpeak>120 mT and cavity voltages>5 MV/cavity.

MOPB074	Thermo-Mechanical Simulations of the Frequency Tuning Plunger for the IFMIF Half-Wave Resonator	niobium, simulation, vacuum, cryomodule	351
	N. Bazin, P. Bosland, S. Chel, G. Devanz, N. Grouas, P. Hardy, J. Migne, F. Orsini, F. Peauger CEA/DSM/IRFU, France
	In the framework of the International Fusion Materials Irradiation Facility (IFMIF), a superconducting option has been chosen for the 5 MeV RF Linac of the first phase of the project (EVEDA), based on a cryomodule composed of 8 HWRs, 8 RF couplers and 8 Solenoid packages. The frequency tuning system of the IFMIF HWR is an innovated system based on a capacitive plunger installed in the electric field region allowing a large tuning range. Following the cold test results obtained on HWR equipped with the first design of plunger in 2011, it was decided to develop a new design of a fully-niobium plunger. The paper will present the development of the new plunger concepts and the thermo-mechanical simulations. For the mechanical simulations, the aim is to sufficiently deform the plunger to tune the cavity while staying in the elastic range of the niobium material. For the thermal simulations, all the non-linear properties of the materials and the effects of the RF fields are taken into account: thermal conductivity and surface resistance are depending on the temperature, RF fields computed with dedicated software are leading to thermal dissipations in the materials and the vacuum seal. F. Orsini et al., “Vertical tests preliminary results of the IFMIF cavity prototypes and cryomodule development”, SRF 2011, Chigaco, USA

MOPB077	Lorentz Force Detuning Compensation Studies for Long Pulses in ILC type SRF Cavities	cryomodule, controls, linac, SRF	354
	N. Solyak, G.I. Cancelo, B. Chase, D.J. Crawford, D.R. Edstrom, Jr, E.R. Harms, Y.M. Pischalnikov, W. Schappert Fermilab, Batavia, USA
	Project-X 3-8 GeV pulsed linac is based on ILC type 1.3 GHz elliptical cavities. The cavity will operate at 25 MV/m accelerating gradient, but in contrast with XFEL and ILC projects the required loaded Q is much higher (Q=10⁷) and RF pulse is much longer (~8ms). For these parameters Lorence force detuning (LFD) and microphonics should be controlled at the level <30 Hz. A new algorithm of LFD compensation, developed at Fermilab for ILC cavities was applied for Lorentz force compensation studies for 8ms pulses. In these studies two cavities inside TESLA-type cryomodule at Fermilab NML facility have been powered by one klystron. Studies done for different cavity gradients and different values of loaded Q demonstrated that required compensation are achievable. Detuning measurements and compensation results are presented.

MOPB079	Normal Conducting Deflecting Cavity Development at the Cockcroft Institute	beam-loading, wakefield, damping, electron	357
	G. Burt, P.K. Ambattu, A.C. Dexter, C. Lingwood, B.J. Woolley Cockcroft Institute, Lancaster University, Lancaster, United Kingdom S.R. Buckley, P. Goudket, C. Hill, P.A. McIntosh, J.W. McKenzie, A.E. Wheelhouse STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom V.A. Dolgashev SLAC, Menlo Park, California, USA A. Grudiev CERN, Geneva, Switzerland R.M. Jones UMAN, Manchester, United Kingdom
	Funding: This work has been supported by STFC and the EU through FP7 EUCARD. Two normal conducting deflecting structures are currently being developed at the Cockcroft Institute, one as a crab cavity for CLIC and one for bunch slice diagnostics on low energy electron beams for EBTF at Daresbury. Each has its own challenges that need overcome. For CLIC the phase and amplitude tolerances are very stringent and hence beamloading effects and wakefields must be minimised. Significant work has been undertook to understand the effect of the couplers on beamloading and the effect of the couplers on the wakefields. For EBTF the difficulty is avoiding the large beam offset caused by the cavities internal deflecting voltage at the low beam energy. Propotypes for both cavities have been manufactured and results will be presented.

MOPB084	Design of a C-band Disk-loaded Type Accelerating Structure for a Higher Pulse Repetition Rate in the SACLA Accelerator.	laser, wakefield, accelerating-gradient, electron	372
	T. Sakurai, T. Inagaki, Y. Otake RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan H. Ego JASRI/SPring-8, Hyogo-ken, Japan
	The higher pulse repetition rate of the SACLA accelerator provides a higher rate of X-ray laser pulses to expand ability of user experiments, such as simultaneously providing the laser to several beamlines and reducing a measuring time in the experiment. Therefore, we studied on a C-band accelerating structure for a higher pulse rate above 120 pps than that of the present case of 60 pps. The designed structure adopts a TM01-2π/3 mode disk-loaded type with a quasi-constant gradient . Since higher repetition rate operation is inclined to increase a number of vacuum electrical discharges, it is required to reduce the surface electric field in the structure. We designed an ellipsoidal curvature shape around an iris aperture, which reduces the maximum surface field by 20%. Since the higher repetition rate also increases the heat load of the structure, in simulation, we optimized cooling channels to obtain acceptable frequency detuning. As the results of the design, an accelerating gradient of more than 40 MV/m will be expected, when an input RF power of 80 MW is applied to the structure. In this paper, we report the design of the C-band accelerating structure and its rf properties.

MOPB088	Fabrication Tests for IMP 162.5 MHz RFQ	rfq, vacuum, gun, linac	381
	B. Zhang IMP, Lanzhou, People's Republic of China
	The RFQ for one of front ends of C-ADS is designed. The frequency of the RFQ is 162.5 MHz and the energy is 2.1 MeV. The beam intensity is 15 mA and it works at CW mode. Because of low frequency, the four-wing structure is big size. It makes fabrication will take more risks. Therefore, four fabrication testing were planned and done to minimize the technic risks. The description about fabrication and testing results are presented in the paper.

MOPB090	FRIB Technology Demonstration Cryomodule Test	cryomodule, SRF, resonance, solenoid	386
	J. Popielarski, E.C. Bernard, S. Bricker, S. Chouhan, C. Compton, A. Facco, A. Fila, L.L. Harle, M. Hodek, L. Hodges, S. Jones, M. Leitner, D. R. Miller, S.J. Miller, D. Morris, R. Oweiss, J.P. Ozelis, L. Popielarski, K. Saito, N.R. Usher, J. Weisend, Y. Zhang, S. Zhao, Z. Zheng FRIB, East Lansing, USA M. Klaus Technische Universität Dresden, Dresden, Germany
	A Technology Demonstration Cryomodule (TDCM) has been developed for a systems test of technology being developed for FRIB. The TDCM consists of two half wave resonators (HWRs) which have been designed for an optimum velocity of β=v/c=0.53 and a resonant frequency of 322 MHz. The resonators operate at 2 K. A superconducting 9 T solenoid is placed in close proximity to one of the installed HWRs. The 9 T solenoid operates at 4 K. A complete systems test of the cavities, magnets, and all ancillary components is presented in this paper. This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE SC0000661.

MOPB091	The Injector Cryomodule for the ARIEL e-Linac at TRIUMF	cryomodule, linac, TRIUMF, cryogenics	389
	R.E. Laxdal, A. Koveshnikov, N. Muller, W.R. Rawnsley, G. Stanford, V. Zvyagintsev TRIUMF, Vancouver, Canada M. Ahammed, M. Mondrel VECC, Kolkata, India
	The ARIEL project at TRIUMF includes a 50 MeV-10 mA electron linear accelerator (e-Linac) using 1.3 GHz superconducting technology. The accelerator is divided into three cryomodules including a single cavity injector cryomodule (ICM) and two accelerating cryomodules with two cavities each. The ICM is being built first. The ICM utilizes a unique top-loading box vacuum vessel. The shape allows the addition of a 4 K/2 K cryogenic unit that accepts near atmospheric LHe and converts to 2 K liquid inside the cryomodule. The cryomodule design is complete and in fabrication. The 4 K/2 K cryogenic unit has been assembled and tested in a test cryostat. The paper will describe the design of the cryomodule and the results of the cryogenic tests.

MOPB094	Simulation Study on the Longitudinal Bunch Shape Measurement by RF Chopper at J-PARC Linac	emittance, simulation, linac, DTL	395
	T. Maruta JAEA/J-PARC, Tokai-mura, Japan M. Ikegami J-PARC, KEK & JAEA, Ibaraki-ken, Japan
	A RF chopper is placed in the medium energy transport section (MEBT1) at J-PARC linac. The chopper is normally driven at synchronous phase of 0 degree to give a maximum deflection. The chopper has two RF gaps and both of them deflect a beam bunch horizontally while RF is on. In the MEBT1 section, while we have a transverse emittance monitor, there is no longitudinal monitor. It is hard to newly place a longitudinal beam monitor there due to space limitation. We conduct a simulation which studies on the usability of the chopper to a longitudinal beam monitor. When the synchronous phase of the chopper is ± 90 degree, the longitudinal beam profile is projected to horizontal beam distribution. In this presentation, we introduce simulation results.

TU1A01	Status of the IFMIF-EVEDA 9 MeV 125 mA Deuteron Linac	rfq, linac, solenoid, SRF	407
	A. Mosnier Fusion for Energy, Garching, Germany
	The scope of IFMIF/EVEDA has been recently revised to set priority on the validation activities, especially on the Accelerator Prototype (LIPAc) with extending the duration up to mid 2017 in order to better fit the development of the challenging components and the commissioning of the whole accelerator. The present status of LIPAc, currently under construction at Rokkasho in Japan, outlines of the engineering design and of the developments of the major components will be reported. In conclusion, the expected outcomes of the engineering work, associated with the experimental program will be presented.
	Slides TU1A01 [7.602 MB]

TU1A04	FRIB Accelerator Status and Challenges	linac, ion, cryomodule, target	417
	J. Wei, E.C. Bernard, N.K. Bultman, F. Casagrande, S. Chouhan, C. Compton, K.D. Davidson, A. Facco, P.E. Gibson, T . Glasmacher, K. Holland, M.J. Johnson, S. Jones, D. Leitner, M. Leitner, G. Machicoane, F. Marti, D. Morris, J.P. Ozelis, S. Peng, J. Popielarski, L. Popielarski, E. Pozdeyev, T. Russo, K. Saito, R.C. Webber, M. Williams, Y. Yamazaki, A. Zeller, Y. Zhang, Q. Zhao FRIB, East Lansing, USA D. Arenius, V. Ganni JLAB, Newport News, Virginia, USA J.A. Nolen ANL, Argonne, 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 Facility for Rare Isotope Beams (FRIB) at MSU includes a driver linac that can accelerate all stable isotopes to energies beyond 200 MeV/u at beam powers up to 400 kW. The linac consists of 330 superconducting quarter- and half-wave resonators operating at 2 K temperature. Physical challenges include acceleration of multiple charge states of beams to meet beam-on-target requirements, efficient production and acceleration of intense heavy-ion beams from low to intermediate energies, accommodation of multiple charge stripping scenarios (liquid lithium, helium gas, and carbon foil) and ion species, designs for both baseline in-flight fragmentation and ISOL upgrade options, and design considerations of machine availability, tunability, reliability, maintainability, and upgradability. We report on the FRIB accelerator design and developments with emphasis on technical challenges and progress.
	Slides TU1A04 [4.531 MB]

TU2A04	High Current ERL at BNL	electron, linac, gun, SRF	437
	I. Ben-Zvi BNL, Upton, Long Island, New York, USA
	The electron hadron collider eRHIC will collide polarized and unpolarized electrons with a current of 50 mA and energy in the range of 5 GeV to 30 GeV with hadron beams, including heavy ions or polarized light ions of the RHIC storage ring. The electron beam will be generated in an energy recovery linac contained inside the RHIC tunnel, comprising six passes through two linac section of about 2.5 GeV each. The electron ERL poses many challenges in term of a high-current high-polarization electron gun, HOM damping in the linac, crab cavities, harmonic cavities and beam stability.
	Slides TU2A04 [2.227 MB]

TUPLB07	Reduced-beta Cavities for High-intensity Compact Accelerators	ion, electron, niobium, heavy-ion	458
	Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, J.W. Morgan, R.C. Murphy, P.N. Ostroumov, T. Reid ANL, Argonne, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract number DE-AC02-06CH11357 and WFO 8R268. This paper reports on the development and testing of a superconducting quarter-wave and a superconducting half-wave resonator. The quarter-wave resonator is designed for β = 0.077 ions, operates at 72 MHz and can provide more than 7.4 MV of accelerating voltage at the design beta, with peak surface fields of 164 mT and 117 MV/m. Operation was limited to this level not by RF surface defects but by our available RF power and administrative limits on x-ray production. A similar goal is being pursued in the development of a half-wave resonator designed for β = 0.29 ions and operated at 325 MHz.

TUPLB08	R&D Towards CW Ion Linacs at ANL	cryomodule, rfq, ion, acceleration	461
	P.N. Ostroumov, A. Barcikowski, Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.V. Kutsaev, J.W. Morgan, R.C. Murphy, B. Mustapha, D.R. Paskvan, T. Reid, D.L. Schrage, S.I. Sharamentov, K.W. Shepard, G.P. Zinkann ANL, Argonne, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics and Nuclear Physics, under Contract DE-AC02-76CH03000, DE-AC02-06CH11357 and ANL WFO 85Y47. The accelerator development group in ANL’s Physics Division has engaged in substantial R&D related to CW proton and ion accelerators. Particularly, a 4 meter long 60.625 MHz CW RFQ has been developed, built and is being commissioned with beam. Development and fabrication of a cryomodule with seven 72.75 MHz quarter-wave cavities is complete and it is being assembled. Off-line testing of several QWRs has demonstrated outstanding performance in terms of both accelerating voltage and surface resistance. Both the RFQ and cryomodule were developed and built to upgrade ATLAS to higher efficiency and beam intensities. Another cryomodule with eight 162.5 MHz SC HWRs and eight SC solenoids is being developed and built for Project X at FNAL. We are also developing both an RFQ and cryomodules (housing 176 MHz HWRs) for proton & deuteron acceleration at SNRC (Soreq, Israel). In this paper we discuss ANL-developed technologies for normal-conducting and SC accelerating structures for medium- and high-power CW accelerators, including the projects mentioned above and other developments for applications such as transmutation of spent reactor fuel.
	Slides TUPLB08 [1.414 MB]

TUPB006	Stability Performance of the Injector for SACLA/XFEL at SPring-8	laser, controls, undulator, FEL	486
	T. Asaka, T. Hasegawa, T. Inagaki, H. Maesaka, T. Ohshima, Y. Otake, S. Takahashi, K. Togawa RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
	To realize the SACLA, it is necessary to obtain stabilities of 10^-4 and 50 fs in the amplitude and time of an acceleration voltage, respectively. The achievement of the rf stabilities were almost satisfactory for the target values. Consequently, the 7 GeV beam energy stability was 0.02% (std.) or less. However, there was XFEL power variation caused by a variation of a beam position in a 40 MeV injector section. A periodically changed beam position of 40 μm (std.) was found out at a cycle of 2 s by Fourier transform method using BPM data. The temperatures of all the injector rf cavities are controlled within 28±0.04˚C by a controller using the cooling water. The AC power supplies of the controller to heat the cooling water are operated at 0.5 Hz by pulse width modulation control with alternatively turning on or off. The strong correlation between laser intensity variation and the modulation frequency of the AC power supplies was found out. We are planning to improve the cavity temperature variation in the order of less than 0.01˚C with DC power supplies to establish continuously regulated the cavity temperature. This plan will reduce the XFEL power variation.

TUPB019	Second CW and LP Operation Test of XFEL Prototype Cryomodule	cryomodule, feedback, HOM, LLRF	516
	J.K. Sekutowicz, V. Ayvazyan, J. Branlard, M. Ebert, J. Eschke, A. Gössel, D. Kostin, W. Merz, F. Mittag, R. Onken DESY, Hamburg, Germany W. Cichalewski, W. Jałmużna, A. Piotrowski, K.P. Przygoda TUL-DMCS, Łódź, Poland K. Czuba, L. Zembala Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland I.M. Kudla, J. Szewiński NCBJ, Świerk/Otwock, Poland
	In summer 2011, we have performed the first test of continuous wave (cw) and long pulse (lp) operation of the XFEL prototype cryomodule, which originally has been designed for short pulse operation. In April and June 2012, the second test took place, with the next cryomodule prototype. For that test cooling in the cryomodule was improved and new LLRF system has been implemented. In this contribution we discuss results of the second RF test of these new types of operation, which can in the future extend flexibility in the time beam structure of the European XFEL facility

TUPB020	Status of the European XFEL 3.9 GHz system	HOM, status, cryomodule, coupling	519
	E. Vogel DESY, Hamburg, Germany A. Bosotti, P. Michelato, L. Monaco, C. Pagani, R. Paparella, P. Pierini, D. Sertore INFN/LASA, Segrate (MI), Italy E.R. Harms Fermilab, Batavia, USA
	The third harmonic system at 3.9 GHz of the European XFEL injector section will linearize the bunch RF curvature, induced by first accelerating module, before the first compression stage. This paper presents qualification tests on cavity prototypes and the on-going activities towards the realization of the third harmonic section of the European XFEL in view of its commissioning in 2014.

TUPB036	Design of Re-Buncher Cavity for Heavy-ion LINAC in IMP	DTL, simulation, linac, impedance	558
	L.P. Sun, X. Du, Y. He, A. Shi, C. Zhang, Z.L. Zhang IMP, Lanzhou, People's Republic of China
	A re-buncher with spiral arms for a heavy ion linear accelerator named as SSC-LNAC at HIRFL (the heavy ion research facility of Lanzhou) has been constructed. The re-buncher, which is used for beam longitudinal modulation and match between the RFQ and DTL, is designed to be operated in continuous wave (CW) mode at the Medium-Energy Beam-Transport (MEBT) line to maintain the beam intensity and quality. Because of the longitudinal space limitation, the re-buncher has to be very compact and will be built with four gaps. We determined the key parameters of the re-buncher cavity from the simulations using Microwave Studio software, such as the resonant frequency, the quality factor Q and the shunt impedance. The detailed design of a 53.667 MHz spiral cavity and measurement results of its prototype will be presented.

TUPB039	Conceptual Design of Superconducting Heavy Ion Linear Injector for HIAF	cryomodule, linac, ion, solenoid	561
	Z.J. Wang, Y. He, H. Jia, C. Li, S.H. Liu, W. Wu, X.B. Xu, B. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	A heavy ion accelerator facility, High Intensity Heavy Ion Accelerator Facility (HIAF), has been promoted by Institute of Modern Physics （IMP）of Chinese Academy of Sciences (CAS). The injector of the accelerator facility is a superconducting linac. It is a high intensity heavy ion linac and works on pulse mode. The final energy is 150 MeV/u. The accelerated species are from P to Uranium. The linac works with both laser and ECR ion source. The designed current is 20 emA. The general concept of HIAF and the preliminary design of linear injector are presented in the paper.

TUPB040	Status of the Linac SRF Acquisition for FRIB	linac, cryomodule, SRF, status	564
	M. Leitner, E.C. Bernard, J. Binkowski, B. Bird, S. Bricker, S. Chouhan, C. Compton, K. Elliott, B. Enkhbat, A.D. Fox, L.L. Harle, M. Hodek, M.J. Johnson, I.M. Malloch, D. R. Miller, S.J. Miller, T. Nellis, D. Norton, R. Oweiss, J.P. Ozelis, J. Popielarski, L. Popielarski, K. Saito, M. Shuptar, G.J. Velianoff, J. Wei, M. Williams, K. Witgen, Y. Xu, Y. Yamazaki, Y. Zhang FRIB, East Lansing, USA A. Facco INFN/LNL, Legnaro (PD), Italy
	Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE SC0000661. The Facility for Rare Isotope Beams (FRIB) will utilize a high-intensity, superconducting heavy-ion driver linac to provide stable ion beams from protons to uranium up to energies of >200 MeV/u and at a beam power of up to 400 kW. The ions are accelerated to about 0.5 MeV/u using a room-temperature 80.5 MHz RFQ and injected into a superconducting cw linac consisting of 330 individual low-beta cavities in 49 cryomodules operating at 2 K. This paper discusses the current status of the linac SRF acquisition strategy as the project phases into construction mode.

TUPB042	Progress on RFQIII Fabrication in J-PARC Linac	rfq, linac, vacuum, alignment	570
	T. Morishita JAEA/LINAC, Ibaraki-ken, Japan K. Hasegawa, Y. Kondo JAEA, Ibaraki-ken, Japan H. Kawamata, F. Naito, T. Sugimura KEK, Ibaraki, Japan
	The J-PARC accelerator comprises an injector linac, a 3 GeV Rapid-Cycling Synchrotron and a 50 GeV Main Ring. The J-PARC linac has been operating for users with the beam energy of 181 MeV. The energy (to 400 MeV) and current (to 50 mA) upgrade of the linac is scheduled for 1MW operation at RCS. For the current upgrade, the fabrication of a new RFQ, which is designed for 50 mA acceleration, has been started. The engineering design and the fabrication technologies were carefully chosen to reduce the discharge risk during the operation. For good vacuum pumping, vanes and ports are brazed for the direct pumping through slits at the tuners. Also, we tried a chemical polishing to improve the smoothness of the vane surface. In this paper, we present the fabrication progress of a new RFQ in J-PARC linac.

TUPB046	R&D Towards CW Ion Linacs at ANL	cryomodule, rfq, ion, acceleration	579
	P.N. Ostroumov, A. Barcikowski, Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.V. Kutsaev, J.W. Morgan, R.C. Murphy, B. Mustapha, D.R. Paskvan, T. Reid, D.L. Schrage, S.I. Sharamentov, K.W. Shepard, G.P. Zinkann ANL, Argonne, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics and Nuclear Physics, under Contract DE-AC02-76CH03000, DE-AC02-06CH11357 and ANL WFO 85Y47. The accelerator development group in ANL’s Physics Division has engaged in substantial R&D related to CW proton and ion accelerators. Particularly, a 4 meter long 60.625 MHz CW RFQ has been developed, built and is being commissioned with beam. Development and fabrication of a cryomodule with seven 72.75 MHz quarter-wave cavities is complete and it is being assembled. Off-line testing of several QWRs has demonstrated outstanding performance in terms of both accelerating voltage and surface resistance. Both the RFQ and cryomodule were developed and built to upgrade ATLAS to higher efficiency and beam intensities. Another cryomodule with eight 162.5 MHz SC HWRs and eight SC solenoids is being developed and built for Project X at FNAL. We are also developing both an RFQ and cryomodules (housing 176 MHz HWRs) for proton & deuteron acceleration at SNRC (Soreq, Israel). In this paper we discuss ANL-developed technologies for normal-conducting and SC accelerating structures for medium- and high-power CW accelerators, including the projects mentioned above and other developments for applications such as transmutation of spent reactor fuel.

TUPB047	Status of the Superconducting RF Activities for the HIE ISOLDE Project	factory, linac, niobium, SRF	582
	W. Venturini Delsolaro, L. Alberty Vieira, S. Calatroni, O. Capatina, A. D'Elia, B. Delaup, M.A. Fraser, N.M. Jecklin, Y. Kadi, P. Maesen, I. Mondino, E. Montesinos, M. Therasse, D. Valuch CERN, Geneva, Switzerland
	The planned upgrade of the REX ISOLDE facility at CERN will boost the energy of the machine from 3 MeV/u up to 10 MeV/u with beams of mass-to-charge ratio 2.5 < A/q < 4. For this purpose, a new superconducting post accelerator based on independently phased 10¹.28 MHz Quarter Wave Resonators (QWR) will replace part of the normal conducting Linac. The QWRs make use of the Niobium sputtering on Copper technology which was successfully applied to LEP2, LHC and to the energy upgrade of the ALPI Linac at INFN-LNL. The status of advancement of the project will be detailed, limited to the SRF activities.

TUPB048	Discussion of the Optimisation of a Linac Lattice to Minimise Disruption by a Class of Parasitic Modes	coupling, linac, simulation, lattice	585
	S. Molloy ESS, Lund, Sweden R. Ainsworth Royal Holloway, University of London, Surrey, United Kingdom
	It is well known that each resonant mode in the RF spectrum of multi-cell accelerating cavities will split into a passband containing a number of modes, and that the coupling of these modes to the beam is dependent on the velocity of the accelerated particles. If these modes are found to degrade the quality of the beam, it is possible to take various measures to damp them, and thus keep their effect below some critical threshold. In the case of the parasitic modes within the same passband as the fundamental accelerating mode, their frequency is typically too close to that of the fundamental to allow their power to be safely extracted, and so cavity designers must rely on the natural damping of the cavity itself. This note contains a theoretical discussion of the coupling of the beam to these passband modes for a large class of accelerating cavities, and provides a mathematical model for use during the design and optimisation of linacs.

TUPB052	Studies of Parasitic Cavity Modes for Proposed ESS Linac Lattices	linac, simulation, proton, lattice	591
	R. Ainsworth Royal Holloway, University of London, Surrey, United Kingdom S. Molloy ESS, Lund, Sweden
	The European Spallation Source (ESS) planned for construction in Lund, Sweden, will be the worlds most intense source of pulsed neutrons. The neutrons will be generated by the collision of a 2.5 GeV proton beam with a heavy-metal target. The superconducting section of the proton linac is split into three different types of cavities, and a question for the lattice designers is at which points in the beamline these splits should occur. This note studies various proposed designs for the ESS lattice from the point of view of the effect on the beam dynamics of the parasitic cavity modes lying close in frequency to the fundamental accelerating mode. Each linac design is characterised by the initial kinetic energy of the beam, as well as by the velocity of the beam at each of the points at which the cavity style changes. The scale of the phase-space disruption of the proton pulse is discussed, and some general conclusions for lattice designers are stated.

TUPB053	Main Coupler Design for Project X	vacuum, radiation, linac, cryomodule	594
	S. Kazakov, S. Cheban, T.N. Khabiboulline, M. Kramp, Y. Orlov, V. Poloubotko, O. Pronitchev, V.P. Yakovlev Fermilab, Batavia, USA M.S. Champion ORNL, Oak Ridge, Tennessee, USA
	A multi-megawatt proton/H⁻ source, Project X, is under development at Fermi National Accelerator Laboratory. Main element of it is a 3 GeV superconducting proton linac which includes 5 families of superconducting cavities of three frequencies: 162.5, 325 and 650 MHz. Scope of this paper is the development of power couplers for 325 and 650 MHz at FNAL. Upgraded version of the accelerator will require two types of couplers, which reliably can operate at CW power level ~25 kW at 325 MHz and ~100 kW at 650 MHz respectively. In this paper we are describing the current design of these devices.

TUPB054	Coherent Effects of High Current Beam in Project-X Linac	HOM, linac, emittance, cryogenics	597
	A.I. Sukhanov, I.V. Gonin, T.N. Khabiboulline, A. Lunin, A. Saini, N. Solyak, A. Vostrikov, V.P. Yakovlev Fermilab, Batavia, USA
	Resonance excitation of longitudinal high order modes in superconducting RF structures of Project X CW linac is studied. We analyze regimes of operation of the linac with high beam current, which can be used to provide an intense muon source for the future Neutrino Factory or Muon Collider, and also important for the Accelerator-Driven Subcritical (ADS) systems. We calculate power loss and associated heat load to the cryogenic system. Longitudinal emittance growth is estimated. We consider an alternative design of the elliptical cavity for the high energy part of linac, which is more suitable for high current operation.

TUPB055	R&D of IMP Superconducting HWR for China ADS	simulation, niobium, linac, proton	600
	W.M. Yue, X.L. Guo, S. He, Y. He, R.X. Wang, P.R. Xiong, M.X. Xu, B. Zhang, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	The R&D program of IMP superconducting HWR is based on the China ADS, The aim is to build and test a HWR prototype on December 2012. We have designed a 162.5 MHz β=0.09 half-wave resonator (HWR), and a copper HWR has been fabricated in January 2012. The fabrication of a Nb HWR will be completed by September 2012, and the fabrication of a slow tuner and a high power coupler for this HWR will be completed then. In this poster, we present the HWR electromagnetic design, mechanical design, fabrication arts, copper HWR RF test result, the design of the slow tuner and the power coupler.

TUPB056	The Multipacting Simulation for the New-shaped QWR using TRACK3P	simulation, accelerating-gradient, electron, niobium	603
	C. Zhang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, S.H. Zhang, S.X. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	In order to improve the electro-magnetic performance of the quarter wave resonator, a new-shaped cavity with an elliptical cylinder outer conductor has been proposed. This novel cavity design can provide much lower peak surface magnetic field and much higher Ra/Q0 and G. The Multipacting simulation has been done for this new QWR cavity using ACE3P/TRACK3P code, in this paper the simulation results will be presented and analyzed.

TUPB057	Structural Analysis of the New-Shaped QWR for HIAF in IMP	simulation, superconducting-cavity, SRF, controls	606
	C. Zhang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, S.H. Zhang, S.X. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	Since the QWR cavity is very successful for the operation with frequency of 48 to 160 MHz and \beta value of 0.001 to 0.2, a new-shaped QWR is being designed for the low energy superconducting section of HIAF in the Institute of Modern Physics. The cavity will work at 81.25 MHz and \beta of 0.085，with a elliptical cylinder outer conductor to better its electro-magnetic performance and keep limited accelerating space. Structural design is an important aspect of the overall cavity implementation, and in order to minimize the frequency shift of the cavity due to the helium bath pressure fluctuations, the Lorentz force and microphonic excitation, stiffening elements have to be applied. In this paper, structural analyses of the new-shaped QWR are presented and stiffening methods are explored.

TUPB058	An Analytical Cavity Model for Fast Linac-Beam Tuning	multipole, quadrupole, dipole, simulation	609
	Z.Q. He, Z. Zheng TUB, Beijing, People's Republic of China Z.Q. He, Z. Liu, J. Wei, Y. Zhang FRIB, East Lansing, Michigan, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 Non-axisymmetric RF cavities can produce axially asymmetric acceleration fields. Conventional method using numerical 3-D field tracking to address this feature is time-consuming and thus not appropriate for on-line beam tuning applications. In this paper, we develop analytical treatment of non-axisymmetric RF cavities. Multipole models of cavities are derived using realistic 3-D field in both longitudinal and transverse dimensions. Then, beam dynamics formulism is established. Finally, special case of FRIB quarter-wave resonators are calculated by the model and benchmarked against 3-D field tracking to ensure the efficiency and accuracy of the model.

TUPB060	Multipacting Suppression Modeling for Half Wave Resonator and RF Coupler*	simulation, electron, cryomodule, impedance	612
	Z. Zheng, A. Facco, Z. Liu, J. Popielarski, K. Saito, J. Wei, Y. Xu, Y. Zhang FRIB, East Lansing, Michigan, USA Z. Zheng TUB, Beijing, People's Republic of China
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 In prototype cryomodule test of Facility of Rare Isotope Beam (FRIB) β=0.53 half-wave-resonators (HWRs) severe multipacting barriers, prevented RF measurement at the full field specified. The multipacting could not be removed by several hours of RF conditioning. To better understand and to eliminate multipacting, physics models and CST simulations have been developed for both cavity and RF coupler. The simulations have good agreement with the multipacting discovered in coupler and cavity testing. Proposed cavity and coupler geometric optimizations are discussed in this paper.

TUPB061	ADRC Control for Beam Loading and Microphonics	controls, beam-loading, LLRF, simulation	615
	Z. Zheng, Z. Liu, J. Wei, Y. Zhang, S. Zhao FRIB, East Lansing, Michigan, USA Z. Zheng TUB, Beijing, People's Republic of China
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 Superconducting RF (SRF) cavities are subject to many disturbances such as beam loading and microphonics. Although we implemented Proportional Integral (PI) control and Active Disturbance Rejection Control (ADRC) in the Low Level RF (LLRF) system at FRIB to stabilize the RF field, the control loop gains are inadequate in the presence of beam loading and microphonics. An improved scheme is proposed and simulated with much higher gains are achieved. The feasibility to include piezo tuner in ADRC and PI circuit is also presented in this paper.

TUPB062	Longitudinal Dynamic Analysis for the Project X 3-8 GeV Pulsed Linac	controls, linac, cryomodule, injection	618
	G.I. Cancelo, B. Chase, Y.I. Eidelman, S. Nagaitsev, N. Solyak Fermilab, Batavia, USA
	The Pulsed Linac is a will require over 200 9-cell, 1300 MHz cavities packed in 26 ILC type cryomodules to accelerate 1 mA average beam current from 3GeV to 8 GeV. The architecture of the RF must optimize RF power, beam emittance, and energy gain amid a large number of requirement and constraints. The pulse length is a critical issue. Ideally, a 26 ms pulse would allow direct injection into the Fermilab’s Main Injector, bypassing the need of the Fermilab’s Recicler. High loaded quality factors (QL) are also desirable to minimize RF power. These requirements demand an accurate control of the cavity resonant frequency disturbed by Lorentz Force Detuning and microphonics. Also the LLRF control system must regulate the RF amplitude and phase within tight bounds amid a long list of dynamic disturbances. The present work describes the simulation efforts and measurements at Fermilab facilities.

TUPB066	Reduced-beta Cavities for High-intensity Compact Accelerators	ion, electron, niobium, heavy-ion	621
	Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, J.W. Morgan, R.C. Murphy, P.N. Ostroumov, T. Reid ANL, Argonne, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract number DE-AC02-06CH11357 and WFO 8R268. This paper reports on the development and testing of a superconducting quarter-wave and a superconducting half-wave resonator. The quarter-wave resonator is designed for β = 0.077 ions, operates at 72 MHz and can provide more than 7.4 MV of accelerating voltage at the design beta, with peak surface fields of 164 mT and 117 MV/m. Operation was limited to this level not by RF surface defects but by our available RF power and administrative limits on x-ray production. A similar goal is being pursued in the development of a half-wave resonator designed for β = 0.29 ions and operated at 325 MHz.

TUPB067	Development of a Superconducting Half-Wave Resonator for PXIE	simulation, linac, cryomodule, niobium	624
	Z.A. Conway, R.L. Fischer, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.V. Kutsaev, B. Mustapha, P.N. Ostroumov, K.W. Shepard ANL, Argonne, USA I.V. Gonin, A. Lunin, V.P. Yakovlev Fermilab, Batavia, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics and Nuclear Physics, under contract DE-AC02-76CH03000 and DE-AC02-06CH11357 An ambitious upgrade to the FNAL accelerator complex is progressing in the Project-X Injector Experiment (PXIE). The PXIE accelerator requires 8 superconducting half-wave resonators optimized for the acceleration of 1 mA β = 0.11 H⁻ ion beams. Here we present the status of the half-wave resonator development, focusing particularly on cavity design, with a brief update on prototype fabrication.

TUPB068	Cryomodule Designs for Superconducting Half-Wave Resonators	cryomodule, vacuum, alignment, solenoid	627
	Z.A. Conway, G.L. Cherry, R.L. Fischer, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.H. Kim, J.W. Morgan, P.N. Ostroumov, K.W. Shepard ANL, Argonne, USA
	Funding: This work was supported by the U.S. DOE, Office of Nuclear Physics, contract number DE-AC02-06CH11357, WFO 85Y47 supported by SNRC, and WFO 82308 supported by Fermi National Accelerator Laboratory. In this paper we present advanced techniques for the construction of half-wave resonator cryomodules. Recent advances in superconducting low-beta cavity design and processing have yielded dramatically improved cavity performance which reduce accelerator cost and improve operational reliability. This improvement has led to the proposal and construction of half-wave resonators by ANL for the acceleration of 0.1 < \beta < 0.5 ions, e.g., the SARAF Phase-II project at SNRC (SOREQ, Israel) and Project-X at Fermilab. These cryomodules build and improve upon designs and techniques recently implemented in upgrades to ATLAS at ANL. Design issues include the ease of assembly/maintenance, resonator cleanliness, operating at 2 or 4 Kelvin, and ancillary system interfacing.

TUPB071	First Measurements on the 325 MHz Superconducting CH Cavity	simulation, controls, linac, coupling	636
	M. Busch, F.D. Dziuba, H. Podlech, U. Ratzinger IAP, Frankfurt am Main, Germany M. Amberg HIM, Mainz, Germany W.A. Barth, S. Mickat GSI, Darmstadt, Germany M. Pekeler RI Research Instruments GmbH, Bergisch Gladbach, Germany
	Funding: Work supported by GSI, BMBF Contr. No. 06FY7102, 06FY9089I At the Institute for Applied Physics (IAP), Frankfurt University, a superconducting 325 MHz CH-Cavity has been designed and built. This 7-cell cavity has a geometrical \beta of 0.16 corresponding to a beam energy of 11.4 AMeV. The design gradient is 5 MV/m. Novel features of this resonator are a compact design, low peak fields, easy surface processing and power coupling. Furthermore a new tuning system based on bellow tuners inside the resonator will control the frequency during operation. After successful rf tests in Frankfurt the cavity will be tested with a 10 mA, 11.4 AMeV beam delivered by the GSI UNILAC. In this paper first measurements and corresponding simulations will be presented.

TUPB072	Status of the Superconducting CW Demonstrator for GSI	linac, simulation, solenoid, cryogenics	639
	F.D. Dziuba, M. Amberg, M. Busch, H. Podlech, U. Ratzinger IAP, Frankfurt am Main, Germany K. Aulenbacher IKP, Mainz, Germany W.A. Barth, S. Mickat GSI, Darmstadt, Germany
	Funding: Helmholtz Institut Mainz (HIM), GSI, BMBF Contr. No. 06FY7102 Since the existing UNILAC at GSI will be used as an injector for the FAIR facility a new superconducting (sc) continous wave (cw) LINAC is highly requested by a broad community of future users to fulfil the requirements of nuclear chemistry, especially in the research field of Super Heavy Elements (SHE). This LINAC is under design in collaboration with the Institute for Applied Physics (IAP) of Frankfurt University, GSI and the Helmholtz Institut Mainz (HIM). It will consist of 9 sc Crossbar-H-mode (CH) cavities operated at 217 MHz which provide an energy up to 7.3 AMeV. Currently, a prototype of the cw LINAC is under development. This demonstrator comprises the first sc CH cavity of the LINAC embedded between two sc solenoids mounted in a horizontal cryomodule. One important milestone of the project will be a full performance test of the demonstrator by injecting and accelerating a beam from the GSI High Charge State Injector (HLI) in 2014. The status of the demonstrator is presented.

TUPB073	Design and Simulation of a Test Model for a Tri-Spoke Cavity at RIKEN	simulation, vacuum, superconducting-cavity, electron	642
	L. Lu RIKEN, Saitama, Japan O. Kamigaito, N. Sakamoto, K. Suda, K. Yamada RIKEN Nishina Center, Wako, Japan
	A design for a tri-spoke-type superconducting cavity for uranium beams with β = 0.303 and a 219 MHz operational frequency is presented. And a test model designed and assembled by two end-wall flanges and one triparted part of the designed tri-spoke cavity, was expected to be built using the same fabrication technology that is supposed for Nb cavity manufacture. The designs and simulations of the tri-spoke cavity and the test model will be reported in this paper.

TUPB074	Superconducting CW Heavy Ion Linac at GSI	linac, ion, heavy-ion, solenoid	645
	W.A. Barth, V. Gettmann, S. Mickat GSI, Darmstadt, Germany W.A. Barth, P. Gerhard HIM, Mainz, Germany
	Funding: Helmholtz Institute Mainz (HIM) An upgrade program has to be realized in the next years, such that enhanced primary beam intensities at the experiment target are available. For this a new sc 28 GHz full performance ECR ion source is under development. Via a new low energy beam line an already installed new RFQ and an IH-DTL will provide for cw-heavy ion beams with high average beam intensity. It is planned to build a new cw-heavy ion-linac behind this high charge state injector. In preparation an R&D program is still ongoing: The first linac section comprising a sc CH-cavity embedded by two sc solenoids (financed by HIM) as a demonstrator will be tested with beam at the GSI High Charge Injector (HLI).The new linac should feed the GSI flagship experiments SHIP and TASCA, as well as material research, biophysics and plasma physics experiments in the MeV/u-area. The linac will be integrated in the GSI-UNILAC-environment; it is housed by the existing constructions. Different layout scenarios of a multipurpose high intensity heavy ion facility will be presented as well as the schedule for preparation and integration of the new cw-linac.

TUPB075	Beam Dynamics Design of China ADS Proton Linac	linac, emittance, rfq, proton	648
	Z. Li, P. Cheng, H. Geng, Z. Guo, C. Meng, B. Sun, J.Y. Tang, F. Yan IHEP, Beijing, People's Republic of China
	Funding: Supported by China ADS Program(XDA03020000), National Natural Science Fundation of China (10875099) and IHEP Special Fundings(Y0515550U1) It is widely accepted that the Accelerator Driven System (ADS) is one of the most promising technical approach to solve the problem of the nuclear wastes, a potential threaten to the sustainable development of the nuclear fission energy. An ADS study program is approved by Chinese Academy of Sciences at 2011, which aims to design and built an ADS demonstration facility with the capability of more than 1000 MW thermal power within the following 25 years. The 15 MW driver accelerator will be designed and constructed by the Institute of High Energy Physics(IHEP) and Institute of Modern Physics(IMP) of China Academy of Sciences. This linac is characterized by the 1.5 GeV energy, 10mA current and CW operation. It is composed by two parallel 10 MeV injectors and a main linac integrated with fault tolerance design. The superconducting acceleration structures are employed except the RFQ. In this paper the general considerations and the beam dynamics design of the driver accelerator will be presented.

TUPB092	High Power Amplifier Systems for SARAF Phase II	controls, rf-amplifier, insertion, status	675
	B. Kaizer, I. Fishman, I.G. Gertz Soreq NRC, Yavne, Israel
	Soreq NRC initiated the establishment of SARAF - Soreq Applied Research Accelerator Facility. SARAF is based on a continuous wave (CW), proton/deuteron RF superconducting linear accelerator with variable energy (5–40 MeV) and current (0.04-5 mA). RF power to each cavity is driven by a High Power Solid State Amplifiers. The paper outlines the design concept of the 10 and 15 kW at 176 MHz power amplifiers that were designed, built, and 10 kW successfully tested. 15 kW is now under construction. The amplifiers are combined from basic 5.5 kW compact 19" 7U water cooled drawer.

TUPB093	Compact 4 kW Variable RF Power Coupler for FRIB Quarter-wave Cavities	cryomodule, vacuum, simulation, linac	678
	M.P. Kelly, Z.A. Conway, M. Kedzie, S.V. Kutsaev ANL, Argonne, USA J.L. Crisp, L.L. Harle FRIB, East Lansing, Michigan, USA
	A new compact 4 kW power coupler has been designed and prototyped at Argonne National Laboratory in collaboration with Michigan State University. The coupler is intended for use on the β=0.085 80.5 MHz superconducting quarter-wave cavities for the FRIB driver linac and also for the planned ReA6 quarter-wave cavity cryomodule. The design has a cold RF window and a 3 cm variable bellows section. The 16 cm overall length of the RF window and bellows facilitates a simple and compact installation onto the cavity inside the clean room. A prototype have been cold tested with high power under realistic conditions at Argonne and results are presented.

TUPB094	High Power Tests of TRASCO RFQ Couplers	vacuum, rfq, simulation, klystron	681
	E. Fagotti, L. Antoniazzi, F. Grespan, A. Palmieri, F. Scarpa INFN/LNL, Legnaro (PD), Italy O. Brunasso Cattarello, R. Panero INFN-Torino, Torino, Italy M. Desmons CEA/DSM/IRFU, France
	The 352.2 MHz 7.13 m long TRASCO RFQ requires an overall amount of 900 kW CW RF power in order to deliver the 40 mA proton beam from the initial energy of 80 keV to the final energy of 5 MeV. For such a purpose a system of eight compact (ϕext=38 mm, ϕint=19.4 mm) loop-based couplers was designed. In a first phase, only the first two (out of six) modules of the RFQ were tested at full power. Therefore only two (out of eight) couplers were used. In order to completely characterize these couplers, a dedicated test bench was prepared, consisting of a bridge waveguide and diagnostics (reflected power, vacuum, arc detectors etc.), onto which a couple of couplers was connected for transmission measurements. Each coupler was tested with a forward power of up to 140 kW. The description of the experimental setup and procedure, as well as the main results of the conditioning procedure will be reported in this paper.

TUPB095	Design of Coupler for Direct Coupled Amplifier to Drift Tube Linac Cavities of the Injector RILAC2 for RIKEN RI Beam Factory	impedance, DTL, coupling, linac	684
	K. Suda, S. Arai, Y. Chiba, O. Kamigaito, M. Kase, H. Okuno, N. Sakamoto, Y. Watanabe, K. Yamada RIKEN Nishina Center, Wako, Japan
	A new linac RILAC2 was constructed at RIKEN RI Beam Factory as an injector for very heavy ions such as uranium and xenon of a high mass to charge ratio m/q ∼ 7, but high intensity ions can be extracted from an ion source. Three drift tube linac cavities, operate in continuous wave mode at 36.5 MHz, have been designed and built. In order to reduce an installation area, and to save a construction cost, we adopted a direct coupling method for a power amplifier without using a long transmission line. A complicated design procedure was performed in order to take into account a change of resonant frequency of the cavity caused by a capacitance of a power tube used in the amplifier. A design of the coupler, as well as the cavity was performed using a three-dimensional electromagnetic calculation code, CST Microwave Studio (MWS). The measured input impedance seen from the amplifier (700 – 1100 Ω) was reproduced well by the calculation of MWS. Also, in order to examine MWS, a case of a coupling with 50 Ω were calculated. The coupling conditions obtained by MWS were compared with the measurement and a calculation with a lumped circuit model.

TUPB097	The C-band RF Pulse Compression for Soft XFEL at SINAP	coupling, simulation, klystron, free-electron-laser	687
	C.P. Wang, Q. Gu, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	A compact soft X-ray free electron laser facility is presently being constructed at shanghai institute of applied physics (SINAP), Chinese academy of science in 2012 and will be accomplished in 2014. This facility requires a compact linac with a high-gradient accelerating structure for a limited overall length less than 230 m. The c-band technology which is already used in KEK/Spring-8 linear accelerator is a good compromise for this compact facility and a c-and traveling-wave accelerating structure was already fabricated and tested at SINAP, so a c-band pulse compression will be required. AND a SLED type RF compression scheme is proposed for the C-band RF system of the soft XFEL and this scheme uses TE0.1.15 mode energy storage cavity for high Q-energy storage. The C-band pulse compression under development at SINAP has a high power gain about 3.1 and it is designed to compress the pulse width from 2.5 μs to 0.5 μs and multiply the input RF power of 50 MW to generate 160 MW peak RF power, and the coupling coefficient will be 8.5. It has three components: 3 dB coupler, mode convertors and the resonant cavities.

TUPB099	Input Coupler of the J-PARC DTL	coupling, DTL, vacuum, linac	690
	F. Naito, K. Nanmo, H. Tanaka KEK, Ibaraki, Japan K. Hirano, T. Ito JAEA/J-PARC, Tokai-mura, Japan
	Each tank of J-PARC DTL has two input couplers. The coupler has a movable coupling　loop with an capacitive element which increase the coupling with the tank. The loop position is the outside of the tank, where is the atmosphere. The tank vacuum is kept by the ceramic window on the wall for the coupler port. The ceramic is made of Aluminum oxide of 99.7 % purity. RF properties and the mechanical structure of the coupler were designed adequately in order to achieve the desired performance. We will report the design of the coupler in detail and the experiences for the practical operation of the DTL.

TUPB100	Recovery and Status Report of DTL/SDTL for the J-PARC After Earthquake	DTL, alignment, linac, target	693
	T. Ito, K. Hirano JAEA/LINAC, Ibaraki-ken, Japan F. Naito, K. Nanmo KEK, Ibaraki, Japan
	The J-PARC facilities had big damages because of the earthquake on March 11, 2011. The J-PARC linac in the tunnel had also damages. For instance the alignment of the cavity was deformed more than 40 mm and there had been observed about 0.2 mm in horizontal direction for a few DTs in the DTL. However, as the result of the recovery work which includes the re-alignment and re-conditioning of whole cavities, we were able to restart the beam acceleration of the linac. The stability of the DTL and SDTL has returned to the state before the earthquake except for a few tanks of SDTL. In this paper, we will present the recovery works from the earthquake and the operating status of the DTL and the SDTL.

TUPB101	Beam Loss Occurred at DTL Cavity in J-PARC Linac	DTL, radiation, linac, drift-tube-linac	696
	A. Miura, K. Hirano, T. Ito, T. Maruta JAEA/J-PARC, Tokai-mura, Japan M. Ikegami J-PARC, KEK & JAEA, Ibaraki-ken, Japan T. Miyao, F. Naito, K. Nanmo KEK, Ibaraki, Japan
	The beam operation of J-PARC linac was suspended until December 2011 due to the damage by the Tohoku earthquake in March 2011. After resumed the operations, we measured the residual radiation along with the beam line during a short interval. Because the higher residual radiation was detected at the surface of drift tube linac (DTL) cavity by radiation survey, we installed the scintillation beam loss monitors (BLM) at the points where the higher radiation was detected to understand the cause of the radiation. Even the DTL section is low energy part of the linac, fine structure of the beam loss was observed by the scintillation BLM. And we measured the beam loss occurred at the DTL with the parameters of beam orbit and cavity settings. Also, the BLM is employed for the linac tuning. In this paper, the result of the radiation measurement and beam loss signals obtained by the scintillation BLMs are presented.

TUPB103	CSNS DTL Prototyping and RF Tuning	DTL, linac, vacuum, quadrupole	702
	H.C. Liu, Q. Chen, S. Fu, K.Y. Gong, A.H. Li, J. Peng, Y.C. Xiao, X. Yin IHEP, Beijing, People's Republic of China
	The 324 MHz Alvarez-type Drift Tube Linac (DTL) for the China spallation neutron source will be used to accelerate the H⁻ ion beam of up to 15 mA peak current from 3 to 80 MeV. It consists of four independent tanks, of which the average length is about 8.6 m. Each tank is divided into three short unit tanks about 2.8 m in length for easy manufacture. A full-scale prototype of the first unit tank with 28 drift tubes containing electromagnetic quadrupoles has been constructed to validate the design and to demonstrate the technology. The overall features of the prototype in both key technology and RF tuning are presented. In particular, the influence of the post couplers was studied in the ramped field DTL.

TUPB107	Amplitude and Phase Control of the Accelerating Field in the ESS Spoke Cavity	controls, feedback, beam-loading, simulation	708
	V.A. Goryashko, R.J.M.Y. Ruber, R.A. Yogi, V.G. Ziemann Uppsala University, Uppsala, Sweden
	We report about numerical simulations of the accelerating field dynamics in the ESS spoke cavity in the presence of the beam loading and Lorentz detuning. A slow feedforward is used to cure the Lorentz detuning whereas a fast feedback through a signal oscillator and cavity pre-detuning technique are applied to eliminate the beam loading effect. An analysis performed with a Simulink model shows that a combination of feedforward, feedback and cavity pre-detuning result in a substantially shorter stabilization time of the field voltage and phase on a required level as compared to a control method using only the feedforward and feedback. The latter allows one to obtain smaller magnitude but longer duration of deviations of the instantaneous voltage and phase from the required nominal values. As a result, a series of cavities only with feedforward and feedback needs an extra control technique to mitigate a cumulative systematic error rising in each cavity. In addition, a technique of adiabatic turning off of the RF power in order to prevent a high reflected power in the case of a sudden beam loss is studied.

WE1A04	The ARIEL Superconducting Electron Linac	cryomodule, gun, TRIUMF, linac	729
	S.R. Koscielniak, F. Ames, R.A. Baartman, I.V. Bylinskii, Y.-C. Chao, D. Dale, R.J. Dawson, E.R. Guetre, N. Khan, A. Koveshnikov, A. Laxdal, R.E. Laxdal, F. Mammarella, M. Marchetto, L. Merminga, A.K. Mitra, T. Planche, Y.-N. Rao, A. Sitnikov, V.A. Verzilov, D. Yosifov, V. Zvyagintsev TRIUMF, Vancouver, Canada D. Karlen, R.R. Langstaff Victoria University, Victoria, B.C., Canada
	The TRIUMF Advanced Rare Isotope Laboratory (ARIEL) is funded since 2010 June by federal and BC Provincial governments. In collaboration with the University of Victoria, TRIUMF is proceeding with construction of a new target building, connecting tunnel, rehabilitation of an existing vault to contain the electron linear accelerator, and a cryogenic compressor building. TRIUMF starts construction of a 300 keV thermionic gun, and 10 MeV Injector cryomodule (EINJ) in 2012; the designs being complete. The 25 MeV Accelerator Cryomodule (EACA) follows in autumn 2013. TRIUMF is embarking on major equipment purchases and has signed contracts for 4K cryogenic plant and four sub-atmospheric pumps, a 290 kW c.w. klystron and high-voltage power supply, 80 quadrupole magnets, EINJ tank and lid, and four 1.3 GHz niobium 9-cell cavities from a local Canadian supplier. The low energy beam transport and beam diagnotics are being installed at the ISAC-II/VECC test facility. Procurement is anticipated October 2012 for the liquid He distribution system.
	Slides WE1A04 [4.305 MB]

TH1A01	Results Achieved by the S1-Global Collaboration for ILC	cryomodule, controls, feedback, LLRF	748
	H. Hayano, M. Akemoto, S. Fukuda, K. Hara, N. Higashi, E. Kako, H. Katagiri, Y. Kojima, Y. Kondo, T. Matsumoto, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, N. Ohuchi, T. Saeki, T. Shidara, T. Shishido, T. Takenaka, A. Terashima, N. Toge, K. Tsuchiya, K. Watanabe, S. Yamaguchi, A. Yamamoto, Y. Yamamoto, K. Yokoya KEK, Ibaraki, Japan C. Adolphsen, C.D. Nantista SLAC, Menlo Park, California, USA T.T. Arkan, S. Barbanotti, M.A. Battistoni, H. Carter, M.S. Champion, A. Hocker, R.D. Kephart, J.S. Kerby, D.V. Mitchell, T.J. Peterson, Y.M. Pischalnikov, M.C. Ross, W. Schappert, B.E. Smith Fermilab, Batavia, USA A. Bosotti, R. Paparella, P. Pierini INFN/LASA, Segrate (MI), Italy K. Jensch, D. Kostin, L. Lilje, A. Matheisen, W.-D. Möller, P. Schilling, M. Schmökel, N.J. Walker, H. Weise DESY, Hamburg, Germany C. Pagani Università degli Studi di Milano & INFN, Segrate, Italy
	The S1-Global collaboration (scope and plans presented at Linac10) ended successfully in 2011. In the S1-Global experiment several variants of ILC components (e.g. cavities, tuners, modules, couplers) proposed by all SCRF collaborators worldwide have been extensively tested and their performances compared, in order to build consensus for the technical choices towards the ILC TDR and to develop further the concept of plug-compatible components for ILC. The experiment has been carried at KEK with contribution of hardware and manpower from all collaborators.
	Slides TH1A01 [6.656 MB]

TH1A02	Compact Superconducting Crabbing and Deflecting Cavities	dipole, HOM, damping, collider	753
	S.U. De Silva ODU, Norfolk, Virginia, USA S.U. De Silva JLAB, Newport News, Virginia, USA
	Recently, new geometries for superconducting crabbing and deflecting cavities have been developed that have significantly improved properties over those the standard TM110 cavities. They are smaller, have low surface fields, high shunt impedance and, more importantly for some of them, no lower-order-mode with a well-separated fundamental mode. This talk will present the status of the development of these cavities.
	Slides TH1A02 [3.811 MB]

TH1A03	Superconducting Spoke Cavities for Electron and High-Velocity Proton Linacs	linac, impedance, SRF, electron	758
	J.R. Delayen ODU, Norfolk, Virginia, USA
	Spoke resonantors are currently under development for many proton machines but these structures are also considered for high beta electron linacs as well. These structures compare well to traditional elliptical cavities.
	Slides TH1A03 [3.570 MB]

TH1A04	Superconducting Linac and Associated Developments at IUAC Delhi	linac, ion, rfq, ECR	763
	A. Roy IUAC, New Delhi, India
	A superconducting linear accelerator system consisting of a series of independently phase locked niobium quarter wave resonators has been developed as a booster of heavy ion beams available from the existing 15UD Pelletron accelerator. Two superconducting linac booster modules having eight niobium quarter wave resonators (QWRs) each have been installed and are fully operational for regular scheduled experiments. The third module is being added to the system. A new high current injector has been planned to couple to the superconducting linac. For this a high temperature superconducting electron cyclotron resonance ion source (HTS-ECRIS) was designed, fabricated and installed successfully. A radio frequency quadrupole (RFQ) accelerator is being developed for accelerating accelerate ions from the ECR (A/Q ~ 6) to an energy to of about 180 keV/A. The beams will then be accelerated further by drift tube linacs (DTL) to the required velocity to inject them to the existing superconducting linac booster. Prototypes of both these have been tested for power and thermal studies. Details of these developments and associated systems will be presented.
	Slides TH1A04 [7.830 MB]

TH2A01	The ESS Linac Design	linac, klystron, cryomodule, proton	768
	M. Lindroos, H. Danared, C. Darve, D.P. McGinnis, S. Molloy ESS, Lund, Sweden
	The European Spallation Source (ESS) is a 5 MW, 2.5 MeV long pulse proton machine. It represents a big jump in power compare to the existing spallation facilities. The design phase is well under way, with the delivery of a Conceptual Design Report expected in 2012, and a Technical Design Report in 2013. Why and how the 5 MW goal influences the parameter choice will be describe.
	Slides TH2A01 [5.667 MB]

TH2A03	Design and Construction of the Linac4 Accelerating Structures	linac, DTL, rfq, vacuum	778
	F. Gerigk, Y. Cuvet, A. Dallocchio, G. Favre, J.-M. Geisser, L. Gentini, J.-M. Giguet, S.J. Mathot, M. Polini, S. Ramberger, B. Riffaud, C. Rossi, P. Ugena Tirado, M. Vretenar, R. Wegner CERN, Geneva, Switzerland E. Kendjebulatov, Ya.G. Kruchkov, A.G. Tribendis BINP SB RAS, Novosibirsk, Russia M.Y. Naumenko RFNC-VNIITF, Snezhinsk, Chelyabinsk region, Russia
	The Linac4 project at CERN is at an advanced state of construction. Prototypes of the different types of accelerating structures (RFQ, DTL, CCDTL and pi-mode structures) have been built and are presently tested. This paper gives the status of the cavity production and reviews the RF and mechanical design of the various structure types. Furthermore the production and the first test results shall be presented.
	Slides TH2A03 [2.675 MB]

TH3A01	Status of ILC	cryomodule, HLRF, linac, linear-collider	787
	A. Yamamoto KEK, Ibaraki, Japan M.C. Ross SLAC, Menlo Park, California, USA N.J. Walker DESY, Hamburg, Germany
	A review of the ILC project with emphasis on the changes in the technical progress report.
	Slides TH3A01 [5.396 MB]

TH3A02	The 12 GeV Energy Upgrade at Jefferson Laboratory	cryomodule, linac, collider, electron	792
	F.C. Pilat JLAB, Newport News, Virginia, USA
	Two new cryomodules and an extensive upgrade of the bending magnets at Jefferson Lab has been recently completed in preparation for the full energy upgrade in about one year.
	Slides TH3A02 [3.482 MB]

THPLB01	Linac Construction for China Spallation Neutron Source	linac, DTL, rfq, neutron	807

Paper

Title

Other Keywords

Page

SUPB004

Linac Optics Design for Multi-turn ERL Light Source

linac, optics, acceleration, cryomodule

7

Y. Petenev, T. Atkinson, A.V. Bondarenko, A.N. Matveenko
HZB, Berlin, Germany

The optics simulation group at HZB is designing a multi-turn energy recovery linac-based light source. Using the superconducting Linac technology, the Femto-Science-Factory (FSF) will provide its users with ultra-bright photon beams of angstrom wavelength at 6 GeV. The FSF is intended to be a multi-user facility and offer a variety of operation modes. In this paper a design of transverse optic of the beam motion in the Linacs is presented. An important point in the optics design was minimization of the beta-functions in the linac at all beam passes to suppress beam break-up (BBU) instability.

SUPB009

Linear Accelerator based on Parallel Coupled Accelerating Structure

electron, controls, focusing, klystron

19

A.E. Levichev, A.M. Barnyakov, V.M. Pavlov
BINP SB RAS, Novosibirsk, Russia
Y.D. Chernousov
ICKC, Novosibirsk, Russia
V. Ivannikov, I.V. Shebolaev
ICKC SB RAS, Novosibirsk, Russia

Accelerating stand based on parallel coupled accelerating structure and electron gun is developed and produced. The structure consists of five accelerating cavities. The RF power feeding of accelerating cavities is provided by common exciting cavity which is performed from rectangular waveguide loaded by reactive pins. Operating frequency is 2450 MHz. Electron gun is made on the basis of RF triode. Linear accelerator was tested with different working regimes. The obtained results are following: energy is up to 4 MeV, accelerating current is up to 300 mA with pulse duration of 2.5 ns on the half of the width; energy is up to 2.5 MeV, accelerating current is up to 100 mA with pulse duration of 5 μs; energy is up to 2.5 MeV, accelerating current is up to 120 mA with pulse duration of 5 μs and beam capture of 100%. The descriptions of the accelerator elements are given in the report. The features of the parallel coupled accelerating structure are discussed. The results of the measuring accelerator’s parameters are presented.

SUPB012

Status of CH Cavity and Solenoid Design of the 17 MeV Injector for MYRRHA

solenoid, focusing, rfq, quadrupole

29

D. Mäder, H. Klein, H. Podlech, U. Ratzinger, C. Zhang
IAP, Frankfurt am Main, Germany

Funding: This work has been supported by the EU (FP7 MAX contract number 269565)
The multifunctional subcritical reactor MYRRHA (Multi-purpose hybrid research reactor for high-tech applications) will be an accelerator driven system (ADS) located in Mol (Belgium). The first accelerating section up to 17 MeV is operated at 176 MHz and consists of a 4-rod-RFQ followed by two room temperature CH cavities with integrated triplet lenses and four superconducting CH structures with intertank solenoids. Each room temperature CH cavity provides about 1 MV effective voltage gain using less than 30 kW of RF power. The superconducting resonators have been optimized for electric peak fields below 30 MV/m and magnetic peak fields below 30 mT. For save operation of the superconducting resonators the magnetic field of the intertank solenoids has to be well shielded towards the CH cavity walls. Different coil geometries have been compared to find the ideal solenoid layout.

SUPB013

The Beam Commissioning Plan of Injector II in C-ADS

rfq, proton, simulation, diagnostics

32

Z.J. Wang, Y. He, H. Jia, C. Li, S.H. Liu, W. Wu, X.B. Xu, B. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

The design work of the Injector II, which is 10 MeV proton linac, in C-ADS project is being finished and some key elements are being fabricated. Now it is necessary to definite the operation mode of beam commissioning, including the selection of the beam current, pulse length and repetition frequency. Also the beam commissions plan should be specified. The beam commissions procedures is simulated with t-mode code GPT. In this paper, the general beam commissioning plan of Injector II in CIADS and simulation results of commissions procedures are presented.

SUPB015

Production and Quality Control of the First Modules of the IFMIF-EVEDA RFQ

survey, controls, coupling, rfq

38

F. Scantamburlo, R. Dima, A. Pepato
INFN- Sez. di Padova, Padova, Italy
C. Roncolato
INFN/LNL, Legnaro (PD), Italy

The IFMIF-EVEDA RFQ, designed to accelerate a 125 mA D⁺ beam from the initial energy of 0.1 MeV to the final energy of 5 MeV at the frequency of 175 MHz, consists of 18 mechanical modules whose length is approximately 54 cm each. The production of the modules has started and, in particular, the modules 16, 17, 15 and 11, plus the prototype modules 1 and 2 have undergone all the production steps, including precision milling and brazing. In this article, the progress of the production, and the quality control during the phases of the production of the modules will be described.

SUPB018

Studies of Parasitic Cavity Modes for Proposed ESS Linac Lattices

linac, simulation, proton, lattice

47

R. Ainsworth
Royal Holloway, University of London, Surrey, United Kingdom
S. Molloy
ESS, Lund, Sweden

The European Spallation Source (ESS) planned for construction in Lund, Sweden, will be the worlds most intense source of pulsed neutrons. The neutrons will be generated by the collision of a 2.5 GeV proton beam with a heavy-metal target. The superconducting section of the proton linac is split into three different types of cavities, and a question for the lattice designers is at which points in the beamline these splits should occur. This note studies various proposed designs for the ESS lattice from the point of view of the effect on the beam dynamics of the parasitic cavity modes lying close in frequency to the fundamental accelerating mode. Each linac design is characterised by the initial kinetic energy of the beam, as well as by the velocity of the beam at each of the points at which the cavity style changes. The scale of the phase-space disruption of the proton pulse is discussed, and some general conclusions for lattice designers are stated.

SUPB019

The Multipacting Simulation for the New-Shaped QWR using TRACK3P

simulation, accelerating-gradient, electron, niobium

50

C. Zhang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, S.H. Zhang, S.X. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

In order to improve the electro-magnetic performance of the quarter wave resonator, a new-shaped cavity with an elliptical cylinder outer conductor has been proposed. This novel cavity design can provide much lower peak surface magnetic field and much higher Ra/Q0 and G. The Multipacting simulation has been done for this new QWR cavity using ACE3P/TRACK3P code, in this paper the simulation results will be presented and analyzed.

SUPB020

Structural Analysis of the New-Shaped QWR for HIAF in IMP

simulation, superconducting-cavity, SRF, controls

53

C. Zhang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, Y.Z. Yang, W.M. Yue, S.H. Zhang, S.X. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China
M.H. Xu
IHEP, Beijing, People's Republic of China

Since the QWR cavity is very successful for the operation with frequency of 48 to 160 MHz and beta value of 0.001 to 0.2, a new-shaped QWR is being designed for the low energy superconducting section of HIAF in the Institute of Modern Physics. The cavity will work at 81.25 MHz and \beta of 0.085，with a elliptical cylinder outer conductor to better its electro-magnetic performance and keep limited accelerating space. Structural design is an important aspect of the overall cavity implementation, and in order to minimize the frequency shift of the cavity due to the helium bath pressure fluctuations, the Lorentz force and microphonic excitation, stiffening elements have to be applied. In this paper, structural analyses of the new-shaped QWR are presented and stiffening methods are explored.

SUPB022

First Measurements on the 325 MHz Superconducting CH Cavity

simulation, controls, linac, coupling

56

M. Busch, F.D. Dziuba, H. Podlech, U. Ratzinger
IAP, Frankfurt am Main, Germany
M. Amberg
HIM, Mainz, Germany
W.A. Barth, S. Mickat
GSI, Darmstadt, Germany
M. Pekeler
RI Research Instruments GmbH, Bergisch Gladbach, Germany

Funding: Work supported by HIM, GSI, BMBF Contr. No. 06FY161I
At the Institute for Applied Physics (IAP), Frankfurt University, a superconducting 325 MHz CH-Cavity has been designed and built. This 7-cell cavity has a geometrical \beta of 0.16 corresponding to a beam energy of 11.4 AMeV. The design gradient is 5 MV/m. Novel features of this resonator are a compact design, low peak fields, easy surface processing and power coupling. Furthermore a new tuning system based on bellow tuners inside the resonator will control the frequency during operation. After successful rf tests in Frankfurt the cavity will be tested with a 10 mA, 11.4 AMeV beam delivered by the GSI UNILAC. In this paper first measurements and corresponding simulations will be presented.

SUPB023

Status of the Superconducting CW Demonstrator for GSI

linac, simulation, solenoid, cryogenics

59

F.D. Dziuba, M. Amberg, M. Busch, H. Podlech, U. Ratzinger
IAP, Frankfurt am Main, Germany
K. Aulenbacher
IKP, Mainz, Germany
W.A. Barth, S. Mickat
GSI, Darmstadt, Germany

Funding: Helmholtz Institut Mainz (HIM), GSI, BMBF Contr. No. 06FY7102
Since the existing UNILAC at GSI will be used as an injector for the FAIR facility a new superconducting (sc) continous wave (cw) LINAC is highly requested by a broad community of future users to fulfil the requirements of nuclear chemistry, especially in the research field of Super Heavy Elements (SHE). This LINAC is under design in collaboration with the Institute for Applied Physics (IAP) of Frankfurt University, GSI and the Helmholtz Institut Mainz (HIM). It will consist of 9 sc Crossbar-H-mode (CH) cavities operated at 217 MHz which provide an energy up to 7.3 AMeV. Currently, a prototype of the cw LINAC is under development. This demonstrator comprises the first sc CH cavity of the LINAC embedded between two sc solenoids mounted in a horizontal cryomodule. One important milestone of the project will be a full performance test of the demonstrator by injecting and accelerating a beam from the GSI High Charge State Injector (HLI) in 2014. The status of the demonstrator is presented.

SUPB025

Development of Superconducting Radio-Frequency (SRF) Deflecting Mode Cavities and Associated Waveguide Dampers for the APS Upgrade Short Pulse X-Ray Project

HOM, photon, cryomodule, damping

65

J.P. Holzbauer, A. Nassiri, G.J. Waldschmidt, G. Wu
ANL, Argonne, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CHI1357.
The Advanced Photon Source Upgrade (APS-U) is a Department of Energy (DoE) funded project to increase the available x-ray beam brightness and add capability to enhance time-resolved experiments on few-ps-scale at APS. A centerpiece of the upgrade is the generation of short pulse x-rays (SPXs) for pump-probe time-resolved capability using SRF deflecting cavities[1]. The SPX project is designed to produce 1-2 ps x-ray pulses for some users compared to the standard 100 ps pulses currently produced. SPX calls for using superconducting rf (SRF) deflecting cavities to give the electrons a correlation between longitudinal position in the bunch and vertical momentum [2]. The light produced by this bunch can be passed through a slit to produce a pulse of light much shorter than the bunch length at reduced flux. The ongoing work of designing these cavities and associated technologies will be presented. This includes the design and prototyping of higher-order (HOM) and lower-order mode (LOM) couplers and dampers as well as the fundamental power coupler (FPC). This work will be given in the context of SPX0, a demonstration cryomodule with two deflecting cavities to be installed in APS in early 2014.
[1] A. Zholents, et al., NIM A 425, 385 (1999)
[2] A. Nassiri, et al., “ Status of the Short-Pulse X-Ray Project at the Advanced Photon Source,” IPAC 2012, New Orleans, LA, May 2012.

SUPB026

Multipacting Analysis of High-velocity Superconducting Spoke Resonators

electron, site, simulation, superconductivity

68

C.S. Hopper, J.R. Delayen
ODU, Norfolk, Virginia, USA

Some of the advantages of superconducting spoke cavities are currently being investigated for the high-velocity regime. When determining a final, optimized geometry, one must consider the possible limiting effects multipacting could have on the cavity. We report on the results of analytical calculations and numerical simulations of multipacting electrons in superconducting spoke cavities and methods for reducing their impact.

SUPB027

Mechanical Study of the First Superconducting Half-wave Resonator for Injector II of CADS Project

simulation, HOM, controls, cryomodule

71

S. He, Y. He, S.C. Huang, F.F. Wang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

Funding: This work is Supported by the National Natural Science Foundation of China (Grant Agreement 91026001)
Within the framework of the China Accelerator-Driven Sub-critical Systems (CADS) project, Institute of Modern Physics (IMP) Chinese Academic of Sciences has proposed a 162.5 MHz Half-Wave Resonator (HWR) Superconducting cavity for low energy section (β=0.09) of high power proton linear accelerators as a new injector II for CIADS. For the geometrical design of superconducting cavities structure mechanical simulations are essential to predict mechanical eigenmodes and the deformation of the cavity walls due to bath pressure effects and the cavity cool-down. Additionally, the tuning analysis has been investigated to control the frequency against microphonics and Lorentz force detuning. Therefore, several RF, static structure, thermal and modal analysis with a three-dimensional Finite-Element Method (FEM) code Traditional ANSYS have been performed.

SUPB028

The Superconducting CH Cavity Development in IMP*

simulation, linac, niobium, resonance

74

M.X. Xu, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, Z.J. Wang, J.W. Xia, Y.Z. Yang, W.M. Yue, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

Funding: Work supported by 91026001 Nature Science Foundation of China
The Cross-Bar H-type (CH) cavity is a multi-gap drift tube structure operated in the H21 mode [1]. The Institute of Modern Physics (IMP) has been doing research and development on this type of superconducting CH cavity which can work at the C-ADS (accelerator driver sub-critical system of China). A new geometry CH cavity has been proposed which have smaller radius. It’s suitable in fabrication, and it’s can reduce cost too .Detailed numerical simulations with CST MicroWave Studio have been performed. An overall surface reduction of 30% against the old structure seems feasible. A copper model CH cavity is being fabrication for validating the simulations and the procedure of fabricating niobium cavity.

SUPB029

Impact of Trapped Flux and Systematic Flux Expulsion in Superconducting Niobium

niobium, SRF, controls, superconductivity

77

J.M. Vogt, J. Knobloch, O. Kugeler
HZB, Berlin, Germany

The intrinsic quality factor Q₀ of superconducting cavities is known to depend on various factors like niobium material properties, treatment history and magnetic shielding. We already reported an additional impact of temperature gradients during the cool-down on the obtained Q₀. We believe cooling conditions can influence the level of flux trapping and hence the residual resistance. For further studies we have constructed a test stand using niobium rods to study flux trapping. Here we can precisely control the temperature and approach T_c in the superconducting state. Although the sample remains in the superconducting state a change in the amount of trapped flux is visible. The procedure can be applied repeatedly resulting in a significantly lowered level of trapped flux in the sample. Applying a similar procedure to a superconducting cavity could allow for reduction of the magnetic contribution to the surface resistance and result in a significant improvement of Q₀.

SUPB032

The C-band RF Pulse Compression for Soft XFEL at SINAP

coupling, simulation, klystron, free-electron-laser

83

C.P. Wang, Q. Gu, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

A compact soft X-ray free electron laser facility is presently being constructed at shanghai institute of applied physics (SINAP), Chinese academy of science in 2012 and will be accomplished in 2014. This facility requires a compact linac with a high-gradient accelerating structure for a limited overall length less than 230 m. The c-band technology which is already used in KEK/Spring-8 linear accelerator is a good compromise for this compact facility and a c-and traveling-wave accelerating structure was already fabricated and tested at SINAP, so a c-band pulse compression will be required. AND a SLED type RF compression scheme is proposed for the C-band RF system of the soft XFEL and this scheme uses TE0.1.15 mode energy storage cavity for high Q-energy storage. The C-band pulse compression under development at SINAP has a high power gain about 3.1 and it is designed to compress the pulse width from 2.5 μs to 0.5 μs and multiply the input RF power of 50 MW to generate 160 MW peak RF power, and the coupling coefficient will be 8.5. It has three components: 3 dB coupler, mode convertors and the resonant cavities.

SUPB038

Multipole Field Effects for the Superconducting Parallel-Bar Deflecting/Crabbing Cavities

dipole, multipole, superconductivity, luminosity

92

S.U. De Silva, J.R. Delayen
ODU, Norfolk, Virginia, USA
S.U. De Silva
JLAB, Newport News, Virginia, USA

The superconducting parallel-bar deflecting/crabbing cavity is currently being considered as one of the design options in rf separation for the Jefferson Lab 12 GeV upgrade and for the crabbing cavity for the proposed LHC luminosity upgrade. Knowledge of multipole field effects is important for accurate beam dynamics study of rf structures. The multipole components can be accurately determined numerically using the electromagnetic surface field data in the rf structure. This paper discusses the detailed analysis of those components for the fundamental deflecting/crabbing mode and higher order modes in the parallel-bar deflecting/crabbing cavity.

SUPB039

Compact Superconducting Crabbing and Deflecting Cavities

dipole, HOM, damping, collider

95

S.U. De Silva
ODU, Norfolk, Virginia, USA
S.U. De Silva
JLAB, Newport News, Virginia, USA

Recently, new geometries for superconducting crabbing and deflecting cavities have been developed that have significantly improved properties over those the standard TM110 cavities. They are smaller, have low surface fields, high shunt impedance and, more importantly for some of them, no lower-order-mode with a well-separated fundamental mode. This talk will present the status of the development of these cavities.

MO1A01

Operational Experience and Future Goals of the SARAF Linac at SOREQ

proton, target, linac, neutron

100

D. Berkovits, A. Arenshtam, Y. Ben Aliz, Y. Buzaglo, O. Dudovich, Y. Eisen, I. Eliyahu, G. Feinberg, I. Fishman, I. Gavish, I.G. Gertz, A. Grin, S. Halfon, D. Har-Even, Y.F. Haruvy, T. Hirsch, D. Hirschmann, Z. Horvitz, B. Kaizer, D. Kijel, A. Kreisel, G. Lempert, J. Luner, I. Mardor, A. Perry, E. Reinfeld, J. Rodnizki, G. Shimel, A. Shor, I. Silverman, L. Weissman, E. Zemach
Soreq NRC, Yavne, Israel

SARAF-phase 1 at SOREQ, with its single 6 half-wave resonators cryomodule, is the first high current, superconducting low-beta linac in operation and it is presently delivering cw proton beams in the mA range. A phase 2 is foreseen for this linac which will allow acceleration up to 40 MeV of 2 mA cw proton and deuteron beams. The project status, the operational experience and the future goals of SARAF should be described.

Slides MO1A01 [3.276 MB]

MO1A02

Status of the European XFEL – Constructing the 17.5 GeV Superconducting Linear Accelerator

undulator, electron, photon, klystron

105

W. Decking
DESY, Hamburg, Germany

The European XFEL is presently under construction in Hamburg, Germany. It consists of a 1.2 km long superconducting linac serving an about 3 km long electron beam transport system. Three undulator systems of up to 200 m length each produce hard and soft x-rays via the self-amplified spontaneous emission (SASE) process. We will present the status of the civil construction and the accelerator components. The production of the 100 superconducting accelerator modules is distributed between industries and a collaboration of accelerator laboratories. We describe the carefully orchestrated production sequence, quality assurance measures and risk mitigation mechanisms. The last module is scheduled to be installed in the accelerator in spring 2015 and commissioning with beam will start in summer of that year.

Slides MO1A02 [8.730 MB]

MO1A03

SRF Linac Technology Development at Fermilab

linac, SRF, cryogenics, status

110

V.P. Yakovlev, C.M. Ginsburg
Fermilab, Batavia, USA

Superconducting linear accelerators are developing for different applications – for fundamental researches in High-Energy and High – Intensity Frontiers, nuclear physics, energetics, neutron spallation sources, synchrotron radiation sources, etc. The linac applications dictate the requirements for superconducting acceleration system, and, thus, for SRF technology. Fermilab is currently involved in two projects: ILC and Project X, both are based on SRF technology. For High-Intensity Frontier investigations, the Project X – a multi-experiment facility is developing based on 3 GeV, CW H⁻ linac in the frame of a wide collaboration of US National Laboratories. In a CW H⁻ linac several families of SC cavities are used: half-wave resonators (162.5 MHz); single-spoke cavities, SSR1 and SSR2 (325 MHz); elliptical 5-cell β=0.6 and β=0.9 cavities (650 MHz). Pulsed 3-8 GeV linac and ILC linac are based on 9-cell 1.3 GHz cavities. In the paper the basic requirements and the status of development of SC accelerating cavities, auxiliaries (couplers, tuners, etc.) and cryomodules are presented as well as technology challenges caused by their specifics.

Slides MO1A03 [3.551 MB]

MO3A01

Development of H-mode Linacs for the FAIR Project

linac, DTL, proton, ion

120

G. Clemente, W.A. Barth, L. Groening, S. Mickat, B. Schlitt, W. Vinzenz
GSI, Darmstadt, Germany
R. M. Brodhage, M. Busch, F.D. Dziuba, H. Podlech, U. Ratzinger
IAP, Frankfurt am Main, Germany

H-mode cavities offer outstanding shunt impedances at low beam energies and enable the acceleration of intense ion beams. Crossed-bar H-cavities extend these properties to energies even beyond 100 MeV. Thus, the designs of the new injector linacs for FAIR, i.e. a 70 MeV, 70 mA proton driver for pbar-production and a cw intermediate mass, superconducting ion linac are based on these novel cavities. Several prototypes (normal & super-conducting) have been built and successfully tested. Moreover, designs for a replacement of the 80 MV Alvarez section of the GSI - Unilac will be discussed to improve the capabilities as the future FAIR heavy ion injector.

Slides MO3A01 [2.741 MB]

MO3A02

Commissioning of a New Injector for the RIKEN RI-Beam Factory

DTL, cyclotron, injection, rfq

125

N. Sakamoto, M. Fujimaki, H. Hasebe, Y. Higurashi, O. Kamigaito, H. Okuno, K. Suda, T. Watanabe, K. Yamada
RIKEN Nishina Center, Wako, Japan
R. Koyama
SHI Accelerator Service Ltd., Tokyo, Japan

A new injector for the RIKEN RI-Beam Factory (RIBF) has been fully commissioned since October 2011. The injector accelerates ions of m/q=6.8 up to 670 keV/u. In order to save the cost and space, a direct coupling scheme was adopted for rf coupling between the cavity and amplifier, based on an elaborate design with the Microwave Studio code. It has worked out very stably in these three months, making the uranium beam intensity higher by one order of magnitude. Moreover, it is now possible to operate the RIBF and GARIS facility for the super-heavy element synthesis independently.

Slides MO3A02 [19.503 MB]

MOPLB06

Fermilab 1.3 GHz Superconducting RF Cavity and Cryomodule Program for Future Linacs

cryomodule, status, linear-collider, linac

153

C.M. Ginsburg
Fermilab, Batavia, USA

Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
The proposed Project X accelerator and the International Linear Collider are based on superconducting RF technology. As a critical part of this effort, Fermilab has developed an extensive program in 1.3 GHz SRF cavity and cryomodule development. This program includes cavity inspection, surface processing, clean assembly, low-power bare cavity tests and pulsed high-power dressed cavity tests. Well performing cavities have been assembled into cryomodules for pulsed high-power tests and will be tested with beam. In addition, peripheral hardware such as tuners and couplers are under development. The current status and accomplishments of the Fermilab 1.3 GHz activity will be described, as well as the R&D program to extend the existing SRF pulsed operational experience into the CW regime.

Slides MOPLB06 [1.508 MB]

MOPLB07

Non-destructive Inspections for SC Cavities

target, laser, SRF, cryogenics

156

Y. Iwashita, Y. Fuwa, M. Hashida, K. Otani, S. Sakabe, S. Tokita, H. Tongu
Kyoto ICR, Uji, Kyoto, Japan
H. Hayano, K. Watanabe, Y. Yamamoto
KEK, Ibaraki, Japan

Non-destructive Inspections play important roles to improve yield in production of high-performance SC Cavities. Starting from the high-resolution camera for inspection of the cavity inner surface, high resolution T-map, X-map and eddy current scanner have been developed. We are also investigating radiography to detect small voids inside the Nb EBW seam, where the target resolution is 0.1 mm. We are carrying out radiography tests with X-rays induced from an ultra short pulse intense laser. Recent progress will be presented.

Slides MOPLB07 [5.810 MB]

MOPLB08

Normal Conducting Deflecting Cavity Development at the Cockcroft Institute

beam-loading, wakefield, damping, electron

159

G. Burt, P.K. Ambattu, A.C. Dexter, C. Lingwood, B.J. Woolley
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
S.R. Buckley, P. Goudket, C. Hill, P.A. McIntosh, J.W. McKenzie, A.E. Wheelhouse
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
V.A. Dolgashev
SLAC, Menlo Park, California, USA
A. Grudiev
CERN, Geneva, Switzerland
R.M. Jones
UMAN, Manchester, United Kingdom

Funding: This work has been supported by STFC and the EU through FP7 EUCARD.
Two normal conducting deflecting structures are currently being developed at the Cockcroft Institute, one as a crab cavity for CLIC and one for bunch slice diagnostics on low energy electron beams for EBTF at Daresbury. Each has its own challenges that need overcome. For CLIC the phase and amplitude tolerances are very stringent and hence beamloading effects and wakefields must be minimised. Significant work has been undertook to understand the effect of the couplers on beamloading and the effect of the couplers on the wakefields. For EBTF the difficulty is avoiding the large beam offset caused by the cavities internal deflecting voltage at the low beam energy. Propotypes for both cavities have been manufactured and results will be presented.

Slides MOPLB08 [1.572 MB]

MOPLB10

FRIB Technology Demonstration Cryomodule Test

cryomodule, SRF, resonance, solenoid

165

J. Popielarski, E.C. Bernard, S. Bricker, S. Chouhan, C. Compton, A. Facco, A. Fila, L.L. Harle, M. Hodek, L. Hodges, S. Jones, M. Leitner, D. R. Miller, S.J. Miller, D. Morris, R. Oweiss, J.P. Ozelis, L. Popielarski, K. Saito, N.R. Usher, J. Weisend, Y. Zhang, S. Zhao, Z. Zheng
FRIB, East Lansing, USA
M. Klaus
Technische Universität Dresden, Dresden, Germany

A Technology Demonstration Cryomodule (TDCM) has been developed for a systems test of technology being developed for FRIB. The TDCM consists of two half wave resonators (HWRs) which have been designed for an optimum velocity of β=v/c=0.53 and a resonant frequency of 322 MHz. The resonators operate at 2 K. A superconducting 9 T solenoid is placed in close proximity to one of the installed HWRs. The 9 T solenoid operates at 4 K. A complete systems test of the cavities, magnets, and all ancillary components is presented in this paper.
This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE SC0000661.

Slides MOPLB10 [2.530 MB]

MOPB004

Design and Operation of a Compact 1 MeV X-band Linac

linac, electron, gun, target

183

G. Burt, T.N. Abram, P.K. Ambattu, C. Lingwood
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
I. Burrows, T. Hartnett, J.P. Hindley, C.J. White
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
P.A. Corlett, A.R. Goulden, P.A. McIntosh, K.J. Middleman, Y.M. Saveliev, R.J. Smith
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

A compact 1 MeV linac has been produced at the Cockcroft Institute using X-band RF technology. The linac is powered by a high power X-band magnetron and has a 17 keV 200 mA thermionic gun with a focus electrode for pulsing. A bi-periodic structure with on-axis coupling is used to minimise the radial size of the linac and to reduce the surface electric fields.

MOPB011

Photoinjector of the EBTF/CLARA Facility at Daresbury

gun, laser, vacuum, electron

192

B.L. Militsyn, D. Angal-Kalinin, C. Hill, S.P. Jamison, J.K. Jones, J.W. McKenzie, K.J. Middleman, B.J.A. Shepherd, R.J. Smith, R. Valizadeh, A.E. Wheelhouse
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
N. Bliss, M.D. Roper
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom

A description is given of a photoinjector designed for Compact Linear Advanced Research Accelerator (CLARA) and Electron Beam Test Facility (EBTF), which will eventually be used to drive a compact FEL. The photoinjector is based on a 2.5 cell S-band photocathode RF gun operating with a copper photocathode and driven by a third harmonic of Ti: Sapphire laser (266 nm) installed in dedicated thermally stabilized room. The injector will be operated with laser pulses with an energy of up to 2 mJ, a pulse duration of 100 fs and initially a repetition rate of 10 Hz, with the aim of increasing this eventually to 400 Hz. At a field gradient of 100 MV/m provided by a 10 MW klystron the gun is expected to deliver beam pulses with energy of up to 6 MeV. Duration and emittance of electron bunches essentially depend on the bunch charge and vary from 0.1 ps at 20 pC to 5 ps at 200 pC and from 0.2 to 2 mm mrad respectively. Additional compression of the electron bunches will be provided with a velocity bunching scheme. For thermal stability the low energy part of the injector is mounted on an artificial granite support.

MOPB012

First RF Measurement Results for the European XFEL SC Cavity Production

HOM, controls, factory, higher-order-mode

195

A.A. Sulimov, P.B. Borowiec, V. Gubarev, J. Iversen, D. Kostin, G. Kreps, K. Krzysik, A. Matheisen, W.-D. Möller, D. Reschke, W. Singer
DESY, Hamburg, Germany

The first reference cavities (RCV) for the European XFEL Project are being tested within the collaboration of Research Instruments (RI), E. ZANON, IFJ-PAN and DESY: - production and warm RF measurements of cavities and their components at RI and ZANON; - surface preparation at DESY; - cold RF tests at DESY by IFJ-PAN. Purpose of the RCV is to establish a stable cavity fabrication and qualification of the surface preparation infrastructure at industry. All necessary RF measurements were done, starting with mechanical fabrication in 2011, till the tuning and cold cavity RF tests in 2012. We present the first results of RF measurements within RCV production for the European XFEL.

Poster MOPB012 [1.843 MB]

MOPB017

Integration of the European XFEL Accelerating Modules

controls, linac, vacuum, HOM

207

E. Vogel, S. Barbanotti, J. Branlard, H. Brueck, S. Choroba, L. Hagge, K. Jensch, V.V. Katalev, D. Kostin, D. Käfer, L. Lilje, A. Matheisen, W.-D. Möller, D. Nölle, B. Petersen, J. Prenting, D. Reschke, H. Schlarb, M. Schmökel, J.K. Sekutowicz, W. Singer, H. Weise
DESY, Hamburg, Germany
J. Świerbleski, P.B. Borowiec
IFJ-PAN, Kraków, Poland
S. Berry, O. Napoly, B. Visentin
CEA/DSM/IRFU, France
A. Bosotti, P. Michelato
INFN/LASA, Segrate (MI), Italy
W. Kaabi
LAL, Orsay, France
C. Madec
CEA/IRFU, Gif-sur-Yvette, France
E.P. Plawski
NCBJ, Świerk/Otwock, Poland
F. Toral
CIEMAT, Madrid, Spain

The production of the 103 superconducting accelerating modules for the European XFEL is an international effort. Institutes and companies from seven different countries (China, France, Germany, Italy, Poland, Russia and Spain), organized in 12 different work packages contribute with parts, capacity for work and facilities to the production of the modules. Currently the series production of the individual parts started or is approaching. Personnel are trained for the assembly and testing of parts and as well for the complete modules. Here we present an overview and the status of all these activities.

MOPB025

1ms Multi-bunch Electron Beam Acceleration by a Normal Conducting RF Gun and Superconducting Accelerator

gun, laser, emittance, cathode

228

M. Kuriki, S. Hosoda, H. Iijima
HU/AdSM, Higashi-Hiroshima, Japan
H. Hayano, J. Urakawa, K. Watanabe
KEK, Ibaraki, Japan
G. Isoyama, R. Kato, K. Kawase
ISIR, Osaka, Japan
S. Kashiwagi
Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
A. Kuramoto
Sokendai, Ibaraki, Japan
K. Sakaue
RISE, Tokyo, Japan

Funding: Quantum Beam Project by MEXT, Japan
We perform electron beam generation and acceleration of 1 ms long pulse and multi-bunch format at KEK-STF (Superconducting Test Facility). The 1 ms long pulse beam is generated by a normal conducting photo-cathode L-band RF gun. The beam is boosted up to 40 MeV by a super-conducting accelerator. Aim of STF is to establish the super-conducting accelerator technology for ILC (International Linear Collider). The facility is concurrently used to demonstrate high brightness X-ray generation by inverse laser Compton scattering supported by MEXT Quantum Beam project. The RF gun cavity has been fabricated by DESY-FNAL-KEK collaboration. After conditioning process, a stable operation of the cavity up to 4.0 MW RF input with 1 ms pulse was achieved by keeping low dark current. 1 ms pulse generation and acceleration has been confirmed in March 2012. Quasi-monochromatic X-ray generation experiment by Laser-Compton will be carried out at STF from the next coming July. We report the latest status of STF.

MOPB026

TRIUMF/VECC e-Linac Injector Beam Test

diagnostics, linac, gun, cryomodule

231

R.E. Laxdal, F. Ames, Y.-C. Chao, K. Fong, C. Gong, A. Laxdal, M. Marchetto, W.R. Rawnsley, S. Saminathan, V.A. Verzilov, Q. Zheng, V. Zvyagintsev
TRIUMF, Vancouver, Canada
J.M. Abernathy, D. Karlen, D.W. Storey
Victoria University, Victoria, B.C., Canada
A. Chakrabarti, V. Naik
VECC, Kolkata, India

TRIUMF is collaborating with VECC on the design of a 10 MeV injector cryomodule to be used as a front end for a high intensity electron linac. A electron gun and low energy beam transport (LEBT) have been installed in a test area to act as the injector for the cryomodule test. The LEBT includes a wide variety of diagnostics to fully characterize the beam from the gun. A series of beam tests are being conducted during the stage installation. The test configuration details and results of beam tests will be presented.

MOPB030

Performance of First C100 Cryomodules for the CEBAF 12 GeV Upgrade Project

cryomodule, linac, vacuum, instrumentation

237

M.A. Drury, A. Burrill, G.K. Davis, J. Hogan, L.K. King, F. Marhauser, H. Park, J.P. Preble, C.E. Reece, A.V. Reilly, R.A. Rimmer, H. Wang, M. Wiseman
JLAB, Newport News, Virginia, USA

Funding: This manuscript has been authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
The Thomas Jefferson National Accelerator Facility is currently engaged in the 12 GeV Upgrade Project. The goal of the project is a doubling of the available beam energy of CEBAF from 6 GeV to 12 GeV. This increase in beam energy will be due primarily to the construction and installation of ten “C100” cryomodules in the CEBAF linacs. The C100 cryomodules are designed to deliver an average 108 MV each from a string of eight seven-cell, electropolished superconducting RF cavities operating at an average accelerating gradient of 19.2 MV/m. The new cryomodules fit in the same available linac space as the original CEBAF 20 MV cryomodules. Cryomodule production started in September 2010. Initial acceptance testing started in June 2011. The first two C100 cryomodules were installed and tested from August 2011 through October 2011, and successfully operated during the last period of the CEBAF 6 GeV era, which ended in May 2012. This paper will present the results of acceptance testing and commissioning of the C100 style cryomodules to date.

MOPB031

Vibration Response Testing of the CEBAF 12 GeV Upgrade Cryomodules

cryomodule, damping, controls, beam-loading

240

G.K. Davis, J. Matalevich, T. Powers, M. Wiseman
JLAB, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177
The CEBAF 12 GeV upgrade project includes 80 new 7-cell cavities assembled into 10 cryomodules. These cryomodules were tested during production to characterize their microphonic response in situ. For several early cryomodules, detailed (vibration) modal studies of the cryomodule string were performed during the assembly process to identify the structural contributors to the measured cryomodule microphonic response. Structural modifications were then modeled, implemented, and verified by subsequent modal testing and in-situ microphonic response testing. Interim and final results from this multi-stage process will be reviewed.

MOPB035

The Linear Accelerating Structure Development for HLS Upgrade

linac, electron, injection, bunching

252

K. Jin, Y. Hong, G. Huang, D. Jia, S.C. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Hefei Light Source (HLS) is mainly composed of an 800 MeV electron storage ring and a 200 MeV constant-impedance Linac functioning as its injector. A new Linac is developed in view of the Full Energy Injection and the Top-up Injection scheme will be adopted in the HLS upgrade. In this paper, an 800 MeV linear accelerating system construction, the constant-gradient structure design and the symmetry couplers consideration will be described in detail. The manufacture technology, the RF measurement, the high power test results and the accelerating system operation are presented.

MOPB037

Linac Optics Design for Multi-turn ERL Light Source

linac, optics, acceleration, cryomodule

258

Y. Petenev, T. Atkinson, A.V. Bondarenko, A.N. Matveenko
HZB, Berlin, Germany

The optics simulation group at HZB is designing a multi-turn energy recovery linac-based light source. Using the superconducting Linac technology, the Femto-Science-Factory (FSF) will provide its users with ultra-bright photon beams of angstrom wavelength at 6 GeV. The FSF is intended to be a multi-user facility and offer a variety of operation modes. In this paper a design of transverse optic of the beam motion in the Linacs is presented. An important point in the optics design was minimization of the beta-functions in the linac at all beam passes to suppress beam break-up (BBU) instability.

MOPB048

Linear Accelerator Based on Parallel Coupled Accelerating Structure

electron, controls, focusing, klystron

282

A.E. Levichev, A.M. Barnyakov, V.M. Pavlov
BINP SB RAS, Novosibirsk, Russia
Y.D. Chernousov
ICKC, Novosibirsk, Russia
V. Ivannikov, I.V. Shebolaev
ICKC SB RAS, Novosibirsk, Russia

Accelerating stand based on parallel coupled accelerating structure and electron gun is developed and produced. The structure consists of five accelerating cavities. The RF power feeding of accelerating cavities is provided by common exciting cavity which is performed from rectangular waveguide loaded by reactive pins. Operating frequency is 2450 MHz. Electron gun is made on the basis of RF triode. Linear accelerator was tested with different working regimes. The obtained results are following: energy is up to 4 MeV, accelerating current is up to 300 mA with pulse duration of 2.5 ns on the half of the width; energy is up to 2.5 MeV, accelerating current is up to 100 mA with pulse duration of 5 μs; energy is up to 2.5 MeV, accelerating current is up to 120 mA with pulse duration of 5 μs and beam capture of 100%. The descriptions of the accelerator elements are given in the report. The features of the parallel coupled accelerating structure are discussed. The results of the measuring accelerator’s parameters are presented.

MOPB049

Design of Compact C-Band Standing-Wave Accelerator for Medical Radiotherapy

electron, coupling, bunching, focusing

285

H. Yang, M.-H. Cho, W. Namkung
POSTECH, Pohang, Kyungbuk, Republic of Korea
S.H. Kim
ANL, Argonne, USA
J.-S. Oh
NFRI, Daejon, Republic of Korea

Funding: Work supported by POSTECH Physics BK21 Program.
We design a C-band standing-wave accelerator for an X-ray and electron source of medical radiotherapy. The accelerator system is operated two modes, using the X-ray and electron beams. Since two modes require different energy, the accelerator is capable of producing 6-MeV, 100-mA pulsed electron beams with peak 2-MW RF power, and 7.5-MeV, 50 mA electron beams with peak 2.5-MW RF power. The beam is focused by less than 1 mm without external magnets. The accelerating structure is a bi-periodic and on-axis-coupled structure with a built-in bunching section, which consists of 3 bunching cells, 14 normal cells and a coupling cell. It is operated with the π/2-mode standing-wave. The bunching cells are designed to enhance the RF phase focusing. Each cavity is designed by the MWS code within 3% inter-cell coupling. In this paper, we present design details of RF cavities and the beam dynamics.

MOPB052

Fermilab 1.3 GHz Superconducting RF Cavity and Cryomodule Program for Future Linacs

cryomodule, status, linear-collider, linac

291

C.M. Ginsburg
Fermilab, Batavia, USA

Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
The proposed Project X accelerator and the International Linear Collider are based on superconducting RF technology. As a critical part of this effort, Fermilab has developed an extensive program in 1.3 GHz SRF cavity and cryomodule development. This program includes cavity inspection, surface processing, clean assembly, low-power bare cavity tests and pulsed high-power dressed cavity tests. Well performing cavities have been assembled into cryomodules for pulsed high-power tests and will be tested with beam. In addition, peripheral hardware such as tuners and couplers are under development. The current status and accomplishments of the Fermilab 1.3 GHz activity will be described, as well as the R&D program to extend the existing SRF pulsed operational experience into the CW regime.

MOPB053

Non-destructive Inspections for SC Cavities

target, laser, SRF, cryogenics

294

Y. Iwashita, Y. Fuwa, M. Hashida, K. Otani, S. Sakabe, S. Tokita, H. Tongu
Kyoto ICR, Uji, Kyoto, Japan
H. Hayano, K. Watanabe, Y. Yamamoto
KEK, Ibaraki, Japan

Non-destructive Inspections play important roles to improve yield in production of high-performance SC Cavities. Starting from the high-resolution camera for inspection of the cavity inner surface, high resolution T-map, X-map and eddy current scanner have been developed. We are also investigating radiography to detect small voids inside the Nb EBW seam, where the target resolution is 0.1 mm. We are carrying out radiography tests with X-rays induced from an ultra short pulse intense laser. Recent progress will be presented.

MOPB054

Test Results of Tesla-style Cryomodules at Fermilab

cryomodule, SRF, controls, LLRF

297

E.R. Harms, K. Carlson, B. Chase, D.J. Crawford, E. Cullerton, D.R. Edstrom, Jr, A. Hocker, M.J. Kucera, J.R. Leibfritz, O.A. Nezhevenko, D.J. Nicklaus, Y.M. Pischalnikov, P.S. Prieto, J. Reid, W. Schappert, P. Varghese
Fermilab, Batavia, USA

Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
Commissioning and operation of the first Tesla-style Cryomodule (CM-1) at Fermilab was concluded in recent months. It has now been replaced by a second Tesla Type III+ module, RFCA002. It is the first 8-cavity ILC style cryomodule to be built at Fermilab and also the first accelerating cryomodule of the Advanced Superconducting Test Accelerator (ASTA). We report on the operating results of both of these cryomodules.

MOPB055

Development of Superconducting Radio-Frequency (SRF) Deflecting Mode Cavities and Associated Waveguide Dampers for the APS Upgrade Short Pulse X-Ray Project

HOM, photon, cryomodule, damping

300

J.P. Holzbauer, A. Nassiri, G.J. Waldschmidt, G. Wu
ANL, Argonne, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CHI1357.
The Advanced Photon Source Upgrade (APS-U) is a Department of Energy (DoE) funded project to increase the available x-ray beam brightness and add capability to enhance time-resolved experiments on few-ps-scale at APS. A centerpiece of the upgrade is the generation of short pulse x-rays (SPXs) for pump-probe time-resolved capability using SRF deflecting cavities[1]. The SPX project is designed to produce 1-2 ps x-ray pulses for some users compared to the standard 100 ps pulses currently produced. SPX calls for using superconducting rf (SRF) deflecting cavities to give the electrons a correlation between longitudinal position in the bunch and vertical momentum [2]. The light produced by this bunch can be passed through a slit to produce a pulse of light much shorter than the bunch length at reduced flux. The ongoing work of designing these cavities and associated technologies will be presented. This includes the design and prototyping of higher-order (HOM) and lower-order mode (LOM) couplers and dampers as well as the fundamental power coupler (FPC). This work will be given in the context of SPX0, a demonstration cryomodule with two deflecting cavities to be installed in APS in early 2014.
[1] A. Zholents, et al., NIM A 425, 385 (1999)
[2] A. Nassiri, et al., “ Status of the Short-Pulse X-Ray Project at the Advanced Photon Source,” IPAC 2012, New Orleans, LA, May 2012.

MOPB056

Multipacting Analysis of High-Velocity Superconducting Spoke Resonators

electron, site, simulation, superconductivity

303

C.S. Hopper, J.R. Delayen
ODU, Norfolk, Virginia, USA

Some of the advantages of superconducting spoke cavities are currently being investigated for the high-velocity regime. When determining a final, optimized geometry, one must consider the possible limiting effects multipacting could have on the cavity. We report on the results of analytical calculations and numerical simulations of multipacting electrons in superconducting spoke cavities and methods for reducing their impact.

MOPB057

Mechanical Study of the First Superconducting Half-wave Resonator for Injector II of CADS Project

simulation, HOM, controls, cryomodule

306

S. He, Y. He, S.C. Huang, F.F. Wang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

Funding: This work is Supported by the National Natural Science Foundation of China (Grant Agreement 91026001)
Within the framework of the China Accelerator-Driven Sub-critical Systems (CADS) project, Institute of Modern Physics (IMP) Chinese Academic of Sciences has proposed a 162.5 MHz Half-Wave Resonator (HWR) Superconducting cavity for low energy section (β=0.09) of high power proton linear accelerators as a new injector II for CIADS. For the geometrical design of superconducting cavities structure mechanical simulations are essential to predict mechanical eigenmodes and the deformation of the cavity walls due to bath pressure effects and the cavity cool-down. Additionally, the tuning analysis has been investigated to control the frequency against microphonics and Lorentz force detuning. Therefore, several RF, static structure, thermal and modal analysis with a three-dimensional Finite-Element Method (FEM) code Traditional ANSYS have been performed.

MOPB059

The Superconducting CH Cavity Development in IMP*

simulation, linac, niobium, resonance

309

M.X. Xu, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, Z.J. Wang, J.W. Xia, Y.Z. Yang, W.M. Yue, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

Funding: Work supported by 91026001 Nature Science Foundation of China
The Cross-Bar H-type (CH) cavity is a multi-gap drift tube structure operated in the H21 mode [1]. The Institute of Modern Physics (IMP) has been doing research and development on this type of superconducting CH cavity which can work at the C-ADS (accelerator driver sub-critical system of China). A new geometry CH cavity has been proposed which have smaller radius. It’s suitable in fabrication, and it’s can reduce cost too .Detailed numerical simulations with CST MicroWave Studio have been performed. An overall surface reduction of 30% against the old structure seems feasible. A copper model CH cavity is being fabrication for validating the simulations and the procedure of fabricating niobium cavity.

MOPB060

RF Surface Impedance Characterization of Potential New Materials for SRF-based Accelerators

niobium, SRF, impedance, superconductivity

312

B. P. Xiao, G.V. Eremeev, H.L. Phillips, C.E. Reece
JLAB, Newport News, Virginia, USA
M.J. Kelley, B. P. Xiao
The College of William and Mary, Williamsburg, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
In the development of new superconducting materials for possible use in SRF-based accelerators, it is useful to work with small candidate samples rather than complete resonant cavities. The recently commissioned Jefferson Lab rf Surface Impedance Characterization (SIC) system* can presently characterize the central region of 50 mm diameter disk samples of various materials from 2 to 40 K exposed to RF magnetic fields up to 14 mT at 7.4 GHz. We report the measurement results from bulk Nb, thin film Nb on Cu and sapphire substrates, and thin film MgB₂ on sapphire substrate provided by colleagues at JLab and Temple University. We also report on efforts to extend the operating range to higher fields.
* B.P. Xiao, et al., RSI, 2011. 82: p. 056104

MOPB061

The New 2nd Generation SRF R&D Facility at Jefferson Lab: TEDF

SRF, cryomodule, cryogenics, electron

315

C.E. Reece, A.V. Reilly
JLAB, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
The US Department of Energy has funded a near-complete renovation of the SRF-based accelerator research and development facilities at Jefferson Lab. The project to accomplish this, the Technical and Engineering Development Facility (TEDF) Project has completed the first of two phases. An entirely new 3,300 m² purpose-built SRF technical work facility has been constructed and is being occupied in summer of 2012. All SRF work processes with the exception of cryogenic testing has been relocated into the new building. All cavity fabrication, processing, thermal treatment, chemistry, cleaning, and assembly work is collected conveniently into a new LEED-certified building. An innovatively designed 750 m² cleanroom/chemrooms suite provides long-term flexibility for support of multiple R&D and construction projects as well as continued process evolution. The detailed characteristics of this perhaps first 2nd-generation SRF facility will be described.

MOPB062

A New Internal Optical Profilometry System for Characterization of RF Cavity Surfaces – CYCLOPS

controls, ion, feedback, acceleration

318

C.E. Reece, A.D. Palczewski, H. Tian
JLAB, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Jefferson Lab has received and commissioned a new interferometric optical profilometer specifically designed to provide internal surface mapping of elliptical rf cavities. The CavitY CaLibrated Optical Profilometry System – CYCLOPS – provides better than 2 micron lateral resolution and 0.1 micron surface height resolution of programmatically selected locations on the interior surface of multi-cell cavities. The system is being used to provide detailed characterization of surface topographic evolution as a function of applied surface treatments and to investigate particular localized defects. We also intend to use the system for 3D mapping of actual interior rf surface geometry for feedback to structure design model and fabrication tooling. First uses will be illustrated. CYCLOPS was developed and fabricated by MicroDynamics Inc., Woodstock, GA, USA.

MOPB063

Superconducting RF Linac for eRHIC

linac, SRF, HOM, electron

321

S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, H. Hahn, D. Kayran, V. Litvinenko, G.J. Mahler, G.T. McIntyre, V. Ptitsyn, R. Than, J.E. Tuozzolo, W. Xu, A. Zaltsman
BNL, Upton, Long Island, New York, USA
S.A. Belomestnykh
Stony Brook University, Stony Brook, USA

Funding: Work is supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. DOE.
eRHIC will collide high-intensity hadron beams from RHIC with 50-mA electron beam from a six-pass 30-GeV Energy Recovery Linac (ERL), which will utilize 704 MHz superconducting RF accelerating structures. This presentation describes the eRHIC SRF linac requirements, layout and parameters, 5-cell SRF cavity with a new HOM damping scheme, project status and plans.

MOPB064

Developing of Superconducting RF Guns at BNL

gun, SRF, cathode, electron

324

S.A. Belomestnykh, Z. Altinbas, I. Ben-Zvi, J.C. Brutus, D.M. Gassner, H. Hahn, L.R. Hammons, J.P. Jamilkowski, D. Kayran, J. Kewisch, V. Litvinenko, G.J. Mahler, G.T. McIntyre, D. Pate, D. Phillips, T. Rao, S.K. Seberg, T. Seda, B. Sheehy, J. Skaritka, K.S. Smith, R. Than, J.E. Tuozzolo, E. Wang, Q. Wu, W. Xu, A. Zaltsman
BNL, Upton, Long Island, New York, USA
S.A. Belomestnykh, J. Dai, M. Ruiz-Osés, T. Xin
Stony Brook University, Stony Brook, USA
C.H. Boulware, T.L. Grimm
Niowave, Inc., Lansing, Michigan, USA
A. Burrill
JLAB, Newport News, Virginia, USA
R. Calaga
CERN, Geneva, Switzerland
M.D. Cole, A.J. Favale, D. Holmes, J. Rathke, T. Schultheiss, A.M.M. Todd
AES, Medford, NY, USA
X. Liang
SBU, Stony Brook, New York, USA

Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE. The work at Niowave is supported by the US DOE under SBIR contract No. DE-FG02-07ER84861.
BNL is developing several superconducting RF guns for different applications. The first gun is based on a half-cell 1.3 GHz elliptical cavity. This gun is used to study generation of polarized electrons from GaAs photocathodes. The second gun, also of a half-cell elliptical cavity design, operates at 704 MHz and is designed to produce high average current electron beam for the ERL prototype from a multi-alkali photocathodes. The third gun is of a quarter-wave resonator type, operating at 112 MHz. This gun will be used for photocathode studies, including a diamond-amplified cathode, and to generate high charge, low repetition rate beam for the coherent electron cooling experiment. In this presentation we will briefly describe the gun designs, present recent test results and discuss future plans.

MOPB065

Impact of Trapped Magnetic Flux and Systematic Flux Expulsion in Superconducting Niobium

niobium, SRF, controls, superconductivity

327

J.M. Vogt, J. Knobloch, O. Kugeler
HZB, Berlin, Germany

The intrinsic quality factor Q₀ of superconducting cavities is known to depend on various factors like niobium material properties, treatment history and magnetic shielding. We already reported an additional impact of temperature gradients during the cool-down on the obtained Q₀. We believe cooling conditions can influence the level of flux trapping and hence the residual resistance. For further studies we have constructed a test stand using niobium rods to study flux trapping. Here we can precisely control the temperature and approach T_c in the superconducting state. Although the sample remains in the superconducting state a change in the amount of trapped flux is visible. The procedure can be applied repeatedly resulting in a significantly lowered level of trapped flux in the sample. Applying a similar procedure to a superconducting cavity could allow for reduction of the magnetic contribution to the surface resistance and result in a significant improvement of Q₀.

MOPB066

Alternative Approaches for HOM-Damped Cavities

multipole, acceleration, HOM, linac

330

B. Riemann, T. Weis
DELTA, Dortmund, Germany
A. Neumann
HZB, Berlin, Germany

Funding: this work is partly funded by BMBF contract no. 05K10PEA
Elliptical cavities have been a standard in SRF linac technology for 30 years. We present another approach to base cell geometry based on Bezier splines, that leads to equal performance levels and is much more flexible in terms of optimization. Using the BERLinPro main linac as an example, a spline multicell cavity is designed with equal performance goals. For the damping of higher order modes (HOMs), the installation of waveguides at the ends of a multicell cavity is a common approach.

MOPB067

Results and Performance Simulations of the Main Linac Design for BERLinPro

HOM, linac, quadrupole, dipole

333

A. Neumann, W. Anders, J. Knobloch
HZB, Berlin, Germany
K. Brackebusch, T. Flisgen, T. Galek, K. Papke, U. van Rienen
Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
B. Riemann, T. Weis
DELTA, Dortmund, Germany

Funding: this work is partly funded by BMBF contract no. 05K10PEA and 05K10HRC
The Berlin Energy Recovery Linac Project (BERLinPro) is designed to develop and demonstrate CW LINAC technology for 100-mA-class ERLs. High-current operation requires an effective damping of higher-order modes (HOMs) of the 1.3 GHz main-linac cavities. We have studied elliptical 7-cell cavities damped by on the whole five waveguides at both ends. Eigenmode computations for geometrical figures of merit show that the present design should allow successful CW linac operation at the maximum beam current of 100 mA/77 pC bunch charge. To verify the results, the external Q factors are compared to the results of S-Parameter simulations that are postprocessed by a pole-fitting technique. First results of scattering parameter measurement on a room-temperature aluminium model are discussed. An outlook presenting the possibilities of combined multi-cavity simulations is included.

MOPB069

Study of HPR Created Oxide Layer at Nb Surfaces

SRF, vacuum, electron, ion

336

P.V. Tyagi
Sokendai, Ibaraki, Japan
H. Hayano, S. Kato, T. Saeki, M. Sawabe
KEK, Ibaraki, Japan

The performance of superconducting radio frequency (SRF) niobium (Nb) cavities strongly depends on final surface condition. Therefore the surface preparation of these SRF cavities often becomes critical. The preparation of surface includes two steps; surface chemistry (in order to get a smooth surface) and cleaning/rinsing (in order to remove contaminants left after the surface chemistry). As high pressure rinsing (HPR) with ultra pure water (UPW) is most commonly used surface cleaning method after the surface chemistry, it's very interesting to characterize the Nb surfaces after HPR. Results of our surface characterization done by XPS (x-ray photoelectron spectroscopy) with depth profiling show the presence of a thicker oxide surface characterization results show the presence of a thicker oxide layer at Nb surface as an outcome of HPR. In this article, we report the production of oxide layer (FWHM thickness) based on different conditions such as the pressures and doses.

MOPB070

Quality Control of Cleanroom Processing Procedures of SRF Cavities for Mass Production

controls, SRF, acceleration, diagnostics

339

R. Oweiss, K. Elliott, A. Facco, M. Hodek, I.M. Malloch, J. Popielarski, L. Popielarski, K. Saito
FRIB, East Lansing, Michigan, USA

Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661.
Quality control is a key factor in the success of SRF cavity mass production. This paper summarizes ongoing research at the Facility for Rare Isotope Beams FRIB to validate the quality assurance of SRF cavities meanwhile optimizing processing procedures for mass production. Experiments are conducted to correlate surface cleanliness for niobium surfaces with high pressure rinse time using β=0.085 quarter-wave resonators (QWR) cavities. Diagnostic devices; liquid particle counter, surface particle detector and TOC analyzer are used to monitor key parameters for quality control. Rinse water samples are collected during high pressure rinsing to measure liquid particle counts. The SLS 1200 Sampler is used to detect the presence of liquid particles of 0.2 microns and up to 1 micron to set standards for acceptable cleaning thresholds and optimize high pressure rinse time. The QIII+ surface particle detector is used to scan high electric field region for the β=0.085 QWR to ensure high pressure rinsing efficiency. The β=0.085 QWR RF testing data are analyzed and results are presented to demonstrate the correlation between attained acceleration gradients and surface cleanliness.

MOPB071

Process Developments for Superconducting RF Low Beta Resonators for the ReA3 LINAC and Facility for Rare Isotope Beams

vacuum, controls, SRF, linac

342

L. Popielarski, C. Compton, L.J. Dubbs, K. Elliott, A. Facco, L.L. Harle, I.M. Malloch, R. Oweiss, J.P. Ozelis, J. Popielarski, K. Saito
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 Facility for Rare Isotope Beams (FRIB) will utilize over 330 superconducting radio frequency (SRF) low beta cavities for its heavy ion driver linac. The SRF department will process and test all cavities prior to string assembly in the cleanroom. The baseline cavity surface and bulk niobium processing procedures have been established. The methods are being optimized for production process rate benchmarking. Additional processes are being developed to increase flexibility and reduce technical risks. This paper will describe procedure developments and experimental results. Topics include high temperature heat treatment for hydrogen degassing, selective chemical etching for cavity frequency tuning, low-temperature bake out and process quality control.

MOPB072

Multipole Expansion of the Fields in Superconducting High-Velocity Spoke Cavities

multipole, quadrupole, linac, simulation

345

R.G. Olave, J.R. Delayen, C.S. Hopper
ODU, Norfolk, Virginia, USA

Multi-spokes superconducting cavities in the high-beta regime are being considered for a number of applications. In order to accurately model the dynamics of the particles in such cavities, knowledge of the fields off-axis are needed. We present a study of the multipoles expansion of the fields from an EM simulation field data for a two-spoke cavity operating at 325 MHz, β = 0.82 and 500 MHz, β = 1.

MOPB073

Cold Testing of Superconducting 72 MHz Quarter-wave Cavities for ATLAS

cryomodule, niobium, linac, accelerating-gradient

348

M.P. Kelly, Z.A. Conway, S.M. Gerbick, M. Kedzie, R.C. Murphy, P.N. Ostroumov, T. Reid
ANL, Argonne, USA

A set of seven 72 MHz β=0.077 superconducting quarter-wave cavities for a beam intensity upgrade of the ATLAS heavy-ion accelerator has been completed. Cavities have been fabricated using the lessons learned from the worldwide effort to extend the performance of niobium cavities close to the limits of the material. Key developments include the use of electropolishing on the completed cavity and with a temperature control system substantially upgraded from that for elliptical-cell EP systems. Wire EDM, used instead of traditional niobium machining, appears to be effective in eliminating performance limiting defects near the weld seams. Hydrogen degassing at 600C after electropolishing permits practical acceleration at 2 Kelvin with Bpeak>120 mT and cavity voltages>5 MV/cavity.

MOPB074

Thermo-Mechanical Simulations of the Frequency Tuning Plunger for the IFMIF Half-Wave Resonator

niobium, simulation, vacuum, cryomodule

351

N. Bazin, P. Bosland, S. Chel, G. Devanz, N. Grouas, P. Hardy, J. Migne, F. Orsini, F. Peauger
CEA/DSM/IRFU, France

In the framework of the International Fusion Materials Irradiation Facility (IFMIF), a superconducting option has been chosen for the 5 MeV RF Linac of the first phase of the project (EVEDA), based on a cryomodule composed of 8 HWRs, 8 RF couplers and 8 Solenoid packages. The frequency tuning system of the IFMIF HWR is an innovated system based on a capacitive plunger installed in the electric field region allowing a large tuning range. Following the cold test results obtained on HWR equipped with the first design of plunger in 2011*, it was decided to develop a new design of a fully-niobium plunger. The paper will present the development of the new plunger concepts and the thermo-mechanical simulations. For the mechanical simulations, the aim is to sufficiently deform the plunger to tune the cavity while staying in the elastic range of the niobium material. For the thermal simulations, all the non-linear properties of the materials and the effects of the RF fields are taken into account: thermal conductivity and surface resistance are depending on the temperature, RF fields computed with dedicated software are leading to thermal dissipations in the materials and the vacuum seal.
* F. Orsini et al., “Vertical tests preliminary results of the IFMIF cavity prototypes and cryomodule development”, SRF 2011, Chigaco, USA

MOPB077

Lorentz Force Detuning Compensation Studies for Long Pulses in ILC type SRF Cavities

cryomodule, controls, linac, SRF

354

N. Solyak, G.I. Cancelo, B. Chase, D.J. Crawford, D.R. Edstrom, Jr, E.R. Harms, Y.M. Pischalnikov, W. Schappert
Fermilab, Batavia, USA

Project-X 3-8 GeV pulsed linac is based on ILC type 1.3 GHz elliptical cavities. The cavity will operate at 25 MV/m accelerating gradient, but in contrast with XFEL and ILC projects the required loaded Q is much higher (Q=10⁷) and RF pulse is much longer (~8ms). For these parameters Lorence force detuning (LFD) and microphonics should be controlled at the level <30 Hz. A new algorithm of LFD compensation, developed at Fermilab for ILC cavities was applied for Lorentz force compensation studies for 8ms pulses. In these studies two cavities inside TESLA-type cryomodule at Fermilab NML facility have been powered by one klystron. Studies done for different cavity gradients and different values of loaded Q demonstrated that required compensation are achievable. Detuning measurements and compensation results are presented.

MOPB079

Normal Conducting Deflecting Cavity Development at the Cockcroft Institute

beam-loading, wakefield, damping, electron

357

G. Burt, P.K. Ambattu, A.C. Dexter, C. Lingwood, B.J. Woolley
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
S.R. Buckley, P. Goudket, C. Hill, P.A. McIntosh, J.W. McKenzie, A.E. Wheelhouse
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
V.A. Dolgashev
SLAC, Menlo Park, California, USA
A. Grudiev
CERN, Geneva, Switzerland
R.M. Jones
UMAN, Manchester, United Kingdom

Funding: This work has been supported by STFC and the EU through FP7 EUCARD.
Two normal conducting deflecting structures are currently being developed at the Cockcroft Institute, one as a crab cavity for CLIC and one for bunch slice diagnostics on low energy electron beams for EBTF at Daresbury. Each has its own challenges that need overcome. For CLIC the phase and amplitude tolerances are very stringent and hence beamloading effects and wakefields must be minimised. Significant work has been undertook to understand the effect of the couplers on beamloading and the effect of the couplers on the wakefields. For EBTF the difficulty is avoiding the large beam offset caused by the cavities internal deflecting voltage at the low beam energy. Propotypes for both cavities have been manufactured and results will be presented.

MOPB084

Design of a C-band Disk-loaded Type Accelerating Structure for a Higher Pulse Repetition Rate in the SACLA Accelerator.

laser, wakefield, accelerating-gradient, electron

372

T. Sakurai, T. Inagaki, Y. Otake
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
H. Ego
JASRI/SPring-8, Hyogo-ken, Japan

The higher pulse repetition rate of the SACLA accelerator provides a higher rate of X-ray laser pulses to expand ability of user experiments, such as simultaneously providing the laser to several beamlines and reducing a measuring time in the experiment. Therefore, we studied on a C-band accelerating structure for a higher pulse rate above 120 pps than that of the present case of 60 pps. The designed structure adopts a TM01-2π/3 mode disk-loaded type with a quasi-constant gradient . Since higher repetition rate operation is inclined to increase a number of vacuum electrical discharges, it is required to reduce the surface electric field in the structure. We designed an ellipsoidal curvature shape around an iris aperture, which reduces the maximum surface field by 20%. Since the higher repetition rate also increases the heat load of the structure, in simulation, we optimized cooling channels to obtain acceptable frequency detuning. As the results of the design, an accelerating gradient of more than 40 MV/m will be expected, when an input RF power of 80 MW is applied to the structure. In this paper, we report the design of the C-band accelerating structure and its rf properties.

MOPB088

Fabrication Tests for IMP 162.5 MHz RFQ

rfq, vacuum, gun, linac

381

B. Zhang
IMP, Lanzhou, People's Republic of China

The RFQ for one of front ends of C-ADS is designed. The frequency of the RFQ is 162.5 MHz and the energy is 2.1 MeV. The beam intensity is 15 mA and it works at CW mode. Because of low frequency, the four-wing structure is big size. It makes fabrication will take more risks. Therefore, four fabrication testing were planned and done to minimize the technic risks. The description about fabrication and testing results are presented in the paper.

MOPB090

FRIB Technology Demonstration Cryomodule Test

cryomodule, SRF, resonance, solenoid

386

J. Popielarski, E.C. Bernard, S. Bricker, S. Chouhan, C. Compton, A. Facco, A. Fila, L.L. Harle, M. Hodek, L. Hodges, S. Jones, M. Leitner, D. R. Miller, S.J. Miller, D. Morris, R. Oweiss, J.P. Ozelis, L. Popielarski, K. Saito, N.R. Usher, J. Weisend, Y. Zhang, S. Zhao, Z. Zheng
FRIB, East Lansing, USA
M. Klaus
Technische Universität Dresden, Dresden, Germany

A Technology Demonstration Cryomodule (TDCM) has been developed for a systems test of technology being developed for FRIB. The TDCM consists of two half wave resonators (HWRs) which have been designed for an optimum velocity of β=v/c=0.53 and a resonant frequency of 322 MHz. The resonators operate at 2 K. A superconducting 9 T solenoid is placed in close proximity to one of the installed HWRs. The 9 T solenoid operates at 4 K. A complete systems test of the cavities, magnets, and all ancillary components is presented in this paper.
This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE SC0000661.

MOPB091

The Injector Cryomodule for the ARIEL e-Linac at TRIUMF

cryomodule, linac, TRIUMF, cryogenics

389

R.E. Laxdal, A. Koveshnikov, N. Muller, W.R. Rawnsley, G. Stanford, V. Zvyagintsev
TRIUMF, Vancouver, Canada
M. Ahammed, M. Mondrel
VECC, Kolkata, India

The ARIEL project at TRIUMF includes a 50 MeV-10 mA electron linear accelerator (e-Linac) using 1.3 GHz superconducting technology. The accelerator is divided into three cryomodules including a single cavity injector cryomodule (ICM) and two accelerating cryomodules with two cavities each. The ICM is being built first. The ICM utilizes a unique top-loading box vacuum vessel. The shape allows the addition of a 4 K/2 K cryogenic unit that accepts near atmospheric LHe and converts to 2 K liquid inside the cryomodule. The cryomodule design is complete and in fabrication. The 4 K/2 K cryogenic unit has been assembled and tested in a test cryostat. The paper will describe the design of the cryomodule and the results of the cryogenic tests.

MOPB094

Simulation Study on the Longitudinal Bunch Shape Measurement by RF Chopper at J-PARC Linac

emittance, simulation, linac, DTL

395

T. Maruta
JAEA/J-PARC, Tokai-mura, Japan
M. Ikegami
J-PARC, KEK & JAEA, Ibaraki-ken, Japan

A RF chopper is placed in the medium energy transport section (MEBT1) at J-PARC linac. The chopper is normally driven at synchronous phase of 0 degree to give a maximum deflection. The chopper has two RF gaps and both of them deflect a beam bunch horizontally while RF is on. In the MEBT1 section, while we have a transverse emittance monitor, there is no longitudinal monitor. It is hard to newly place a longitudinal beam monitor there due to space limitation. We conduct a simulation which studies on the usability of the chopper to a longitudinal beam monitor. When the synchronous phase of the chopper is ± 90 degree, the longitudinal beam profile is projected to horizontal beam distribution. In this presentation, we introduce simulation results.

TU1A01

Status of the IFMIF-EVEDA 9 MeV 125 mA Deuteron Linac

rfq, linac, solenoid, SRF

407

A. Mosnier
Fusion for Energy, Garching, Germany

The scope of IFMIF/EVEDA has been recently revised to set priority on the validation activities, especially on the Accelerator Prototype (LIPAc) with extending the duration up to mid 2017 in order to better fit the development of the challenging components and the commissioning of the whole accelerator. The present status of LIPAc, currently under construction at Rokkasho in Japan, outlines of the engineering design and of the developments of the major components will be reported. In conclusion, the expected outcomes of the engineering work, associated with the experimental program will be presented.

Slides TU1A01 [7.602 MB]

TU1A04

FRIB Accelerator Status and Challenges

linac, ion, cryomodule, target

417

J. Wei, E.C. Bernard, N.K. Bultman, F. Casagrande, S. Chouhan, C. Compton, K.D. Davidson, A. Facco, P.E. Gibson, T . Glasmacher, K. Holland, M.J. Johnson, S. Jones, D. Leitner, M. Leitner, G. Machicoane, F. Marti, D. Morris, J.P. Ozelis, S. Peng, J. Popielarski, L. Popielarski, E. Pozdeyev, T. Russo, K. Saito, R.C. Webber, M. Williams, Y. Yamazaki, A. Zeller, Y. Zhang, Q. Zhao
FRIB, East Lansing, USA
D. Arenius, V. Ganni
JLAB, Newport News, Virginia, USA
J.A. Nolen
ANL, Argonne, 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 Facility for Rare Isotope Beams (FRIB) at MSU includes a driver linac that can accelerate all stable isotopes to energies beyond 200 MeV/u at beam powers up to 400 kW. The linac consists of 330 superconducting quarter- and half-wave resonators operating at 2 K temperature. Physical challenges include acceleration of multiple charge states of beams to meet beam-on-target requirements, efficient production and acceleration of intense heavy-ion beams from low to intermediate energies, accommodation of multiple charge stripping scenarios (liquid lithium, helium gas, and carbon foil) and ion species, designs for both baseline in-flight fragmentation and ISOL upgrade options, and design considerations of machine availability, tunability, reliability, maintainability, and upgradability. We report on the FRIB accelerator design and developments with emphasis on technical challenges and progress.

Slides TU1A04 [4.531 MB]

TU2A04

High Current ERL at BNL

electron, linac, gun, SRF

437

I. Ben-Zvi
BNL, Upton, Long Island, New York, USA

The electron hadron collider eRHIC will collide polarized and unpolarized electrons with a current of 50 mA and energy in the range of 5 GeV to 30 GeV with hadron beams, including heavy ions or polarized light ions of the RHIC storage ring. The electron beam will be generated in an energy recovery linac contained inside the RHIC tunnel, comprising six passes through two linac section of about 2.5 GeV each. The electron ERL poses many challenges in term of a high-current high-polarization electron gun, HOM damping in the linac, crab cavities, harmonic cavities and beam stability.

Slides TU2A04 [2.227 MB]

TUPLB07

Reduced-beta Cavities for High-intensity Compact Accelerators

ion, electron, niobium, heavy-ion

458

Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, J.W. Morgan, R.C. Murphy, P.N. Ostroumov, T. Reid
ANL, Argonne, USA

Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract number DE-AC02-06CH11357 and WFO 8R268.
This paper reports on the development and testing of a superconducting quarter-wave and a superconducting half-wave resonator. The quarter-wave resonator is designed for β = 0.077 ions, operates at 72 MHz and can provide more than 7.4 MV of accelerating voltage at the design beta, with peak surface fields of 164 mT and 117 MV/m. Operation was limited to this level not by RF surface defects but by our available RF power and administrative limits on x-ray production. A similar goal is being pursued in the development of a half-wave resonator designed for β = 0.29 ions and operated at 325 MHz.

TUPLB08

R&D Towards CW Ion Linacs at ANL

cryomodule, rfq, ion, acceleration

461

P.N. Ostroumov, A. Barcikowski, Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.V. Kutsaev, J.W. Morgan, R.C. Murphy, B. Mustapha, D.R. Paskvan, T. Reid, D.L. Schrage, S.I. Sharamentov, K.W. Shepard, G.P. Zinkann
ANL, Argonne, USA

Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics and Nuclear Physics, under Contract DE-AC02-76CH03000, DE-AC02-06CH11357 and ANL WFO 85Y47.
The accelerator development group in ANL’s Physics Division has engaged in substantial R&D related to CW proton and ion accelerators. Particularly, a 4 meter long 60.625 MHz CW RFQ has been developed, built and is being commissioned with beam. Development and fabrication of a cryomodule with seven 72.75 MHz quarter-wave cavities is complete and it is being assembled. Off-line testing of several QWRs has demonstrated outstanding performance in terms of both accelerating voltage and surface resistance. Both the RFQ and cryomodule were developed and built to upgrade ATLAS to higher efficiency and beam intensities. Another cryomodule with eight 162.5 MHz SC HWRs and eight SC solenoids is being developed and built for Project X at FNAL. We are also developing both an RFQ and cryomodules (housing 176 MHz HWRs) for proton & deuteron acceleration at SNRC (Soreq, Israel). In this paper we discuss ANL-developed technologies for normal-conducting and SC accelerating structures for medium- and high-power CW accelerators, including the projects mentioned above and other developments for applications such as transmutation of spent reactor fuel.

Slides TUPLB08 [1.414 MB]

TUPB006

Stability Performance of the Injector for SACLA/XFEL at SPring-8

laser, controls, undulator, FEL

486

T. Asaka, T. Hasegawa, T. Inagaki, H. Maesaka, T. Ohshima, Y. Otake, S. Takahashi, K. Togawa
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan

To realize the SACLA, it is necessary to obtain stabilities of 10^-4 and 50 fs in the amplitude and time of an acceleration voltage, respectively. The achievement of the rf stabilities were almost satisfactory for the target values. Consequently, the 7 GeV beam energy stability was 0.02% (std.) or less. However, there was XFEL power variation caused by a variation of a beam position in a 40 MeV injector section. A periodically changed beam position of 40 μm (std.) was found out at a cycle of 2 s by Fourier transform method using BPM data. The temperatures of all the injector rf cavities are controlled within 28±0.04˚C by a controller using the cooling water. The AC power supplies of the controller to heat the cooling water are operated at 0.5 Hz by pulse width modulation control with alternatively turning on or off. The strong correlation between laser intensity variation and the modulation frequency of the AC power supplies was found out. We are planning to improve the cavity temperature variation in the order of less than 0.01˚C with DC power supplies to establish continuously regulated the cavity temperature. This plan will reduce the XFEL power variation.

TUPB019

Second CW and LP Operation Test of XFEL Prototype Cryomodule

cryomodule, feedback, HOM, LLRF

516

J.K. Sekutowicz, V. Ayvazyan, J. Branlard, M. Ebert, J. Eschke, A. Gössel, D. Kostin, W. Merz, F. Mittag, R. Onken
DESY, Hamburg, Germany
W. Cichalewski, W. Jałmużna, A. Piotrowski, K.P. Przygoda
TUL-DMCS, Łódź, Poland
K. Czuba, L. Zembala
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
I.M. Kudla, J. Szewiński
NCBJ, Świerk/Otwock, Poland

In summer 2011, we have performed the first test of continuous wave (cw) and long pulse (lp) operation of the XFEL prototype cryomodule, which originally has been designed for short pulse operation. In April and June 2012, the second test took place, with the next cryomodule prototype. For that test cooling in the cryomodule was improved and new LLRF system has been implemented. In this contribution we discuss results of the second RF test of these new types of operation, which can in the future extend flexibility in the time beam structure of the European XFEL facility

TUPB020

Status of the European XFEL 3.9 GHz system

HOM, status, cryomodule, coupling

519

E. Vogel
DESY, Hamburg, Germany
A. Bosotti, P. Michelato, L. Monaco, C. Pagani, R. Paparella, P. Pierini, D. Sertore
INFN/LASA, Segrate (MI), Italy
E.R. Harms
Fermilab, Batavia, USA

The third harmonic system at 3.9 GHz of the European XFEL injector section will linearize the bunch RF curvature, induced by first accelerating module, before the first compression stage. This paper presents qualification tests on cavity prototypes and the on-going activities towards the realization of the third harmonic section of the European XFEL in view of its commissioning in 2014.

TUPB036

Design of Re-Buncher Cavity for Heavy-ion LINAC in IMP

DTL, simulation, linac, impedance

558

L.P. Sun, X. Du, Y. He, A. Shi, C. Zhang, Z.L. Zhang
IMP, Lanzhou, People's Republic of China

A re-buncher with spiral arms for a heavy ion linear accelerator named as SSC-LNAC at HIRFL (the heavy ion research facility of Lanzhou) has been constructed. The re-buncher, which is used for beam longitudinal modulation and match between the RFQ and DTL, is designed to be operated in continuous wave (CW) mode at the Medium-Energy Beam-Transport (MEBT) line to maintain the beam intensity and quality. Because of the longitudinal space limitation, the re-buncher has to be very compact and will be built with four gaps. We determined the key parameters of the re-buncher cavity from the simulations using Microwave Studio software, such as the resonant frequency, the quality factor Q and the shunt impedance. The detailed design of a 53.667 MHz spiral cavity and measurement results of its prototype will be presented.

TUPB039

Conceptual Design of Superconducting Heavy Ion Linear Injector for HIAF

cryomodule, linac, ion, solenoid

561

Z.J. Wang, Y. He, H. Jia, C. Li, S.H. Liu, W. Wu, X.B. Xu, B. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

A heavy ion accelerator facility, High Intensity Heavy Ion Accelerator Facility (HIAF), has been promoted by Institute of Modern Physics （IMP）of Chinese Academy of Sciences (CAS). The injector of the accelerator facility is a superconducting linac. It is a high intensity heavy ion linac and works on pulse mode. The final energy is 150 MeV/u. The accelerated species are from P to Uranium. The linac works with both laser and ECR ion source. The designed current is 20 emA. The general concept of HIAF and the preliminary design of linear injector are presented in the paper.

TUPB040

Status of the Linac SRF Acquisition for FRIB

linac, cryomodule, SRF, status

564

M. Leitner, E.C. Bernard, J. Binkowski, B. Bird, S. Bricker, S. Chouhan, C. Compton, K. Elliott, B. Enkhbat, A.D. Fox, L.L. Harle, M. Hodek, M.J. Johnson, I.M. Malloch, D. R. Miller, S.J. Miller, T. Nellis, D. Norton, R. Oweiss, J.P. Ozelis, J. Popielarski, L. Popielarski, K. Saito, M. Shuptar, G.J. Velianoff, J. Wei, M. Williams, K. Witgen, Y. Xu, Y. Yamazaki, Y. Zhang
FRIB, East Lansing, USA
A. Facco
INFN/LNL, Legnaro (PD), Italy

Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE SC0000661.
The Facility for Rare Isotope Beams (FRIB) will utilize a high-intensity, superconducting heavy-ion driver linac to provide stable ion beams from protons to uranium up to energies of >200 MeV/u and at a beam power of up to 400 kW. The ions are accelerated to about 0.5 MeV/u using a room-temperature 80.5 MHz RFQ and injected into a superconducting cw linac consisting of 330 individual low-beta cavities in 49 cryomodules operating at 2 K. This paper discusses the current status of the linac SRF acquisition strategy as the project phases into construction mode.

TUPB042

Progress on RFQIII Fabrication in J-PARC Linac

rfq, linac, vacuum, alignment

570

T. Morishita
JAEA/LINAC, Ibaraki-ken, Japan
K. Hasegawa, Y. Kondo
JAEA, Ibaraki-ken, Japan
H. Kawamata, F. Naito, T. Sugimura
KEK, Ibaraki, Japan

The J-PARC accelerator comprises an injector linac, a 3 GeV Rapid-Cycling Synchrotron and a 50 GeV Main Ring. The J-PARC linac has been operating for users with the beam energy of 181 MeV. The energy (to 400 MeV) and current (to 50 mA) upgrade of the linac is scheduled for 1MW operation at RCS. For the current upgrade, the fabrication of a new RFQ, which is designed for 50 mA acceleration, has been started. The engineering design and the fabrication technologies were carefully chosen to reduce the discharge risk during the operation. For good vacuum pumping, vanes and ports are brazed for the direct pumping through slits at the tuners. Also, we tried a chemical polishing to improve the smoothness of the vane surface. In this paper, we present the fabrication progress of a new RFQ in J-PARC linac.

TUPB046

R&D Towards CW Ion Linacs at ANL

cryomodule, rfq, ion, acceleration

579

P.N. Ostroumov, A. Barcikowski, Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.V. Kutsaev, J.W. Morgan, R.C. Murphy, B. Mustapha, D.R. Paskvan, T. Reid, D.L. Schrage, S.I. Sharamentov, K.W. Shepard, G.P. Zinkann
ANL, Argonne, USA

Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics and Nuclear Physics, under Contract DE-AC02-76CH03000, DE-AC02-06CH11357 and ANL WFO 85Y47.
The accelerator development group in ANL’s Physics Division has engaged in substantial R&D related to CW proton and ion accelerators. Particularly, a 4 meter long 60.625 MHz CW RFQ has been developed, built and is being commissioned with beam. Development and fabrication of a cryomodule with seven 72.75 MHz quarter-wave cavities is complete and it is being assembled. Off-line testing of several QWRs has demonstrated outstanding performance in terms of both accelerating voltage and surface resistance. Both the RFQ and cryomodule were developed and built to upgrade ATLAS to higher efficiency and beam intensities. Another cryomodule with eight 162.5 MHz SC HWRs and eight SC solenoids is being developed and built for Project X at FNAL. We are also developing both an RFQ and cryomodules (housing 176 MHz HWRs) for proton & deuteron acceleration at SNRC (Soreq, Israel). In this paper we discuss ANL-developed technologies for normal-conducting and SC accelerating structures for medium- and high-power CW accelerators, including the projects mentioned above and other developments for applications such as transmutation of spent reactor fuel.

TUPB047

Status of the Superconducting RF Activities for the HIE ISOLDE Project

factory, linac, niobium, SRF

582

W. Venturini Delsolaro, L. Alberty Vieira, S. Calatroni, O. Capatina, A. D'Elia, B. Delaup, M.A. Fraser, N.M. Jecklin, Y. Kadi, P. Maesen, I. Mondino, E. Montesinos, M. Therasse, D. Valuch
CERN, Geneva, Switzerland

The planned upgrade of the REX ISOLDE facility at CERN will boost the energy of the machine from 3 MeV/u up to 10 MeV/u with beams of mass-to-charge ratio 2.5 < A/q < 4. For this purpose, a new superconducting post accelerator based on independently phased 10¹.28 MHz Quarter Wave Resonators (QWR) will replace part of the normal conducting Linac. The QWRs make use of the Niobium sputtering on Copper technology which was successfully applied to LEP2, LHC and to the energy upgrade of the ALPI Linac at INFN-LNL. The status of advancement of the project will be detailed, limited to the SRF activities.

TUPB048

Discussion of the Optimisation of a Linac Lattice to Minimise Disruption by a Class of Parasitic Modes

coupling, linac, simulation, lattice

585

S. Molloy
ESS, Lund, Sweden
R. Ainsworth
Royal Holloway, University of London, Surrey, United Kingdom

It is well known that each resonant mode in the RF spectrum of multi-cell accelerating cavities will split into a passband containing a number of modes, and that the coupling of these modes to the beam is dependent on the velocity of the accelerated particles. If these modes are found to degrade the quality of the beam, it is possible to take various measures to damp them, and thus keep their effect below some critical threshold. In the case of the parasitic modes within the same passband as the fundamental accelerating mode, their frequency is typically too close to that of the fundamental to allow their power to be safely extracted, and so cavity designers must rely on the natural damping of the cavity itself. This note contains a theoretical discussion of the coupling of the beam to these passband modes for a large class of accelerating cavities, and provides a mathematical model for use during the design and optimisation of linacs.

TUPB052

Studies of Parasitic Cavity Modes for Proposed ESS Linac Lattices

linac, simulation, proton, lattice

591

R. Ainsworth
Royal Holloway, University of London, Surrey, United Kingdom
S. Molloy
ESS, Lund, Sweden

The European Spallation Source (ESS) planned for construction in Lund, Sweden, will be the worlds most intense source of pulsed neutrons. The neutrons will be generated by the collision of a 2.5 GeV proton beam with a heavy-metal target. The superconducting section of the proton linac is split into three different types of cavities, and a question for the lattice designers is at which points in the beamline these splits should occur. This note studies various proposed designs for the ESS lattice from the point of view of the effect on the beam dynamics of the parasitic cavity modes lying close in frequency to the fundamental accelerating mode. Each linac design is characterised by the initial kinetic energy of the beam, as well as by the velocity of the beam at each of the points at which the cavity style changes. The scale of the phase-space disruption of the proton pulse is discussed, and some general conclusions for lattice designers are stated.

TUPB053

Main Coupler Design for Project X

vacuum, radiation, linac, cryomodule

594

S. Kazakov, S. Cheban, T.N. Khabiboulline, M. Kramp, Y. Orlov, V. Poloubotko, O. Pronitchev, V.P. Yakovlev
Fermilab, Batavia, USA
M.S. Champion
ORNL, Oak Ridge, Tennessee, USA

A multi-megawatt proton/H⁻ source, Project X, is under development at Fermi National Accelerator Laboratory. Main element of it is a 3 GeV superconducting proton linac which includes 5 families of superconducting cavities of three frequencies: 162.5, 325 and 650 MHz. Scope of this paper is the development of power couplers for 325 and 650 MHz at FNAL. Upgraded version of the accelerator will require two types of couplers, which reliably can operate at CW power level ~25 kW at 325 MHz and ~100 kW at 650 MHz respectively. In this paper we are describing the current design of these devices.

TUPB054

Coherent Effects of High Current Beam in Project-X Linac

HOM, linac, emittance, cryogenics

597

A.I. Sukhanov, I.V. Gonin, T.N. Khabiboulline, A. Lunin, A. Saini, N. Solyak, A. Vostrikov, V.P. Yakovlev
Fermilab, Batavia, USA

Resonance excitation of longitudinal high order modes in superconducting RF structures of Project X CW linac is studied. We analyze regimes of operation of the linac with high beam current, which can be used to provide an intense muon source for the future Neutrino Factory or Muon Collider, and also important for the Accelerator-Driven Subcritical (ADS) systems. We calculate power loss and associated heat load to the cryogenic system. Longitudinal emittance growth is estimated. We consider an alternative design of the elliptical cavity for the high energy part of linac, which is more suitable for high current operation.

TUPB055

R&D of IMP Superconducting HWR for China ADS

simulation, niobium, linac, proton

600

W.M. Yue, X.L. Guo, S. He, Y. He, R.X. Wang, P.R. Xiong, M.X. Xu, B. Zhang, C. Zhang, S.H. Zhang, S.X. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

The R&D program of IMP superconducting HWR is based on the China ADS, The aim is to build and test a HWR prototype on December 2012. We have designed a 162.5 MHz β=0.09 half-wave resonator (HWR), and a copper HWR has been fabricated in January 2012. The fabrication of a Nb HWR will be completed by September 2012, and the fabrication of a slow tuner and a high power coupler for this HWR will be completed then. In this poster, we present the HWR electromagnetic design, mechanical design, fabrication arts, copper HWR RF test result, the design of the slow tuner and the power coupler.

TUPB056

The Multipacting Simulation for the New-shaped QWR using TRACK3P

simulation, accelerating-gradient, electron, niobium

603

C. Zhang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, S.H. Zhang, S.X. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

In order to improve the electro-magnetic performance of the quarter wave resonator, a new-shaped cavity with an elliptical cylinder outer conductor has been proposed. This novel cavity design can provide much lower peak surface magnetic field and much higher Ra/Q0 and G. The Multipacting simulation has been done for this new QWR cavity using ACE3P/TRACK3P code, in this paper the simulation results will be presented and analyzed.

TUPB057

Structural Analysis of the New-Shaped QWR for HIAF in IMP

simulation, superconducting-cavity, SRF, controls

606

C. Zhang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, R.X. Wang, M.X. Xu, Y.Z. Yang, W.M. Yue, S.H. Zhang, S.X. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

Since the QWR cavity is very successful for the operation with frequency of 48 to 160 MHz and \beta value of 0.001 to 0.2, a new-shaped QWR is being designed for the low energy superconducting section of HIAF in the Institute of Modern Physics. The cavity will work at 81.25 MHz and \beta of 0.085，with a elliptical cylinder outer conductor to better its electro-magnetic performance and keep limited accelerating space. Structural design is an important aspect of the overall cavity implementation, and in order to minimize the frequency shift of the cavity due to the helium bath pressure fluctuations, the Lorentz force and microphonic excitation, stiffening elements have to be applied. In this paper, structural analyses of the new-shaped QWR are presented and stiffening methods are explored.

TUPB058

An Analytical Cavity Model for Fast Linac-Beam Tuning

multipole, quadrupole, dipole, simulation

609

Z.Q. He, Z. Zheng
TUB, Beijing, People's Republic of China
Z.Q. He, Z. Liu, J. Wei, Y. Zhang
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
Non-axisymmetric RF cavities can produce axially asymmetric acceleration fields. Conventional method using numerical 3-D field tracking to address this feature is time-consuming and thus not appropriate for on-line beam tuning applications. In this paper, we develop analytical treatment of non-axisymmetric RF cavities. Multipole models of cavities are derived using realistic 3-D field in both longitudinal and transverse dimensions. Then, beam dynamics formulism is established. Finally, special case of FRIB quarter-wave resonators are calculated by the model and benchmarked against 3-D field tracking to ensure the efficiency and accuracy of the model.

TUPB060

Multipacting Suppression Modeling for Half Wave Resonator and RF Coupler*

simulation, electron, cryomodule, impedance

612

Z. Zheng, A. Facco, Z. Liu, J. Popielarski, K. Saito, J. Wei, Y. Xu, Y. Zhang
FRIB, East Lansing, Michigan, USA
Z. Zheng
TUB, Beijing, People's Republic of China

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
In prototype cryomodule test of Facility of Rare Isotope Beam (FRIB) β=0.53 half-wave-resonators (HWRs) severe multipacting barriers, prevented RF measurement at the full field specified. The multipacting could not be removed by several hours of RF conditioning. To better understand and to eliminate multipacting, physics models and CST simulations have been developed for both cavity and RF coupler. The simulations have good agreement with the multipacting discovered in coupler and cavity testing. Proposed cavity and coupler geometric optimizations are discussed in this paper.

TUPB061

ADRC Control for Beam Loading and Microphonics

controls, beam-loading, LLRF, simulation

615

Z. Zheng, Z. Liu, J. Wei, Y. Zhang, S. Zhao
FRIB, East Lansing, Michigan, USA
Z. Zheng
TUB, Beijing, People's Republic of China

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
Superconducting RF (SRF) cavities are subject to many disturbances such as beam loading and microphonics. Although we implemented Proportional Integral (PI) control and Active Disturbance Rejection Control (ADRC) in the Low Level RF (LLRF) system at FRIB to stabilize the RF field, the control loop gains are inadequate in the presence of beam loading and microphonics. An improved scheme is proposed and simulated with much higher gains are achieved. The feasibility to include piezo tuner in ADRC and PI circuit is also presented in this paper.

TUPB062

Longitudinal Dynamic Analysis for the Project X 3-8 GeV Pulsed Linac

controls, linac, cryomodule, injection

618

G.I. Cancelo, B. Chase, Y.I. Eidelman, S. Nagaitsev, N. Solyak
Fermilab, Batavia, USA

The Pulsed Linac is a will require over 200 9-cell, 1300 MHz cavities packed in 26 ILC type cryomodules to accelerate 1 mA average beam current from 3GeV to 8 GeV. The architecture of the RF must optimize RF power, beam emittance, and energy gain amid a large number of requirement and constraints. The pulse length is a critical issue. Ideally, a 26 ms pulse would allow direct injection into the Fermilab’s Main Injector, bypassing the need of the Fermilab’s Recicler. High loaded quality factors (QL) are also desirable to minimize RF power. These requirements demand an accurate control of the cavity resonant frequency disturbed by Lorentz Force Detuning and microphonics. Also the LLRF control system must regulate the RF amplitude and phase within tight bounds amid a long list of dynamic disturbances. The present work describes the simulation efforts and measurements at Fermilab facilities.

TUPB066

Reduced-beta Cavities for High-intensity Compact Accelerators

ion, electron, niobium, heavy-ion

621

Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, J.W. Morgan, R.C. Murphy, P.N. Ostroumov, T. Reid
ANL, Argonne, USA

Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract number DE-AC02-06CH11357 and WFO 8R268.
This paper reports on the development and testing of a superconducting quarter-wave and a superconducting half-wave resonator. The quarter-wave resonator is designed for β = 0.077 ions, operates at 72 MHz and can provide more than 7.4 MV of accelerating voltage at the design beta, with peak surface fields of 164 mT and 117 MV/m. Operation was limited to this level not by RF surface defects but by our available RF power and administrative limits on x-ray production. A similar goal is being pursued in the development of a half-wave resonator designed for β = 0.29 ions and operated at 325 MHz.

TUPB067

Development of a Superconducting Half-Wave Resonator for PXIE

simulation, linac, cryomodule, niobium

624

Z.A. Conway, R.L. Fischer, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.V. Kutsaev, B. Mustapha, P.N. Ostroumov, K.W. Shepard
ANL, Argonne, USA
I.V. Gonin, A. Lunin, V.P. Yakovlev
Fermilab, Batavia, USA

Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics and Nuclear Physics, under contract DE-AC02-76CH03000 and DE-AC02-06CH11357
An ambitious upgrade to the FNAL accelerator complex is progressing in the Project-X Injector Experiment (PXIE). The PXIE accelerator requires 8 superconducting half-wave resonators optimized for the acceleration of 1 mA β = 0.11 H⁻ ion beams. Here we present the status of the half-wave resonator development, focusing particularly on cavity design, with a brief update on prototype fabrication.

TUPB068

Cryomodule Designs for Superconducting Half-Wave Resonators

cryomodule, vacuum, alignment, solenoid

627

Z.A. Conway, G.L. Cherry, R.L. Fischer, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.H. Kim, J.W. Morgan, P.N. Ostroumov, K.W. Shepard
ANL, Argonne, USA

Funding: This work was supported by the U.S. DOE, Office of Nuclear Physics, contract number DE-AC02-06CH11357, WFO 85Y47 supported by SNRC, and WFO 82308 supported by Fermi National Accelerator Laboratory.
In this paper we present advanced techniques for the construction of half-wave resonator cryomodules. Recent advances in superconducting low-beta cavity design and processing have yielded dramatically improved cavity performance which reduce accelerator cost and improve operational reliability. This improvement has led to the proposal and construction of half-wave resonators by ANL for the acceleration of 0.1 < \beta < 0.5 ions, e.g., the SARAF Phase-II project at SNRC (SOREQ, Israel) and Project-X at Fermilab. These cryomodules build and improve upon designs and techniques recently implemented in upgrades to ATLAS at ANL. Design issues include the ease of assembly/maintenance, resonator cleanliness, operating at 2 or 4 Kelvin, and ancillary system interfacing.

TUPB071

First Measurements on the 325 MHz Superconducting CH Cavity

simulation, controls, linac, coupling

636

M. Busch, F.D. Dziuba, H. Podlech, U. Ratzinger
IAP, Frankfurt am Main, Germany
M. Amberg
HIM, Mainz, Germany
W.A. Barth, S. Mickat
GSI, Darmstadt, Germany
M. Pekeler
RI Research Instruments GmbH, Bergisch Gladbach, Germany

Funding: Work supported by GSI, BMBF Contr. No. 06FY7102, 06FY9089I
At the Institute for Applied Physics (IAP), Frankfurt University, a superconducting 325 MHz CH-Cavity has been designed and built. This 7-cell cavity has a geometrical \beta of 0.16 corresponding to a beam energy of 11.4 AMeV. The design gradient is 5 MV/m. Novel features of this resonator are a compact design, low peak fields, easy surface processing and power coupling. Furthermore a new tuning system based on bellow tuners inside the resonator will control the frequency during operation. After successful rf tests in Frankfurt the cavity will be tested with a 10 mA, 11.4 AMeV beam delivered by the GSI UNILAC. In this paper first measurements and corresponding simulations will be presented.

TUPB072

Status of the Superconducting CW Demonstrator for GSI

linac, simulation, solenoid, cryogenics

639

F.D. Dziuba, M. Amberg, M. Busch, H. Podlech, U. Ratzinger
IAP, Frankfurt am Main, Germany
K. Aulenbacher
IKP, Mainz, Germany
W.A. Barth, S. Mickat
GSI, Darmstadt, Germany

Funding: Helmholtz Institut Mainz (HIM), GSI, BMBF Contr. No. 06FY7102
Since the existing UNILAC at GSI will be used as an injector for the FAIR facility a new superconducting (sc) continous wave (cw) LINAC is highly requested by a broad community of future users to fulfil the requirements of nuclear chemistry, especially in the research field of Super Heavy Elements (SHE). This LINAC is under design in collaboration with the Institute for Applied Physics (IAP) of Frankfurt University, GSI and the Helmholtz Institut Mainz (HIM). It will consist of 9 sc Crossbar-H-mode (CH) cavities operated at 217 MHz which provide an energy up to 7.3 AMeV. Currently, a prototype of the cw LINAC is under development. This demonstrator comprises the first sc CH cavity of the LINAC embedded between two sc solenoids mounted in a horizontal cryomodule. One important milestone of the project will be a full performance test of the demonstrator by injecting and accelerating a beam from the GSI High Charge State Injector (HLI) in 2014. The status of the demonstrator is presented.

TUPB073

Design and Simulation of a Test Model for a Tri-Spoke Cavity at RIKEN

simulation, vacuum, superconducting-cavity, electron

642

L. Lu
RIKEN, Saitama, Japan
O. Kamigaito, N. Sakamoto, K. Suda, K. Yamada
RIKEN Nishina Center, Wako, Japan

A design for a tri-spoke-type superconducting cavity for uranium beams with β = 0.303 and a 219 MHz operational frequency is presented. And a test model designed and assembled by two end-wall flanges and one triparted part of the designed tri-spoke cavity, was expected to be built using the same fabrication technology that is supposed for Nb cavity manufacture. The designs and simulations of the tri-spoke cavity and the test model will be reported in this paper.

TUPB074

Superconducting CW Heavy Ion Linac at GSI

linac, ion, heavy-ion, solenoid

645

W.A. Barth, V. Gettmann, S. Mickat
GSI, Darmstadt, Germany
W.A. Barth, P. Gerhard
HIM, Mainz, Germany

Funding: Helmholtz Institute Mainz (HIM)
An upgrade program has to be realized in the next years, such that enhanced primary beam intensities at the experiment target are available. For this a new sc 28 GHz full performance ECR ion source is under development. Via a new low energy beam line an already installed new RFQ and an IH-DTL will provide for cw-heavy ion beams with high average beam intensity. It is planned to build a new cw-heavy ion-linac behind this high charge state injector. In preparation an R&D program is still ongoing: The first linac section comprising a sc CH-cavity embedded by two sc solenoids (financed by HIM) as a demonstrator will be tested with beam at the GSI High Charge Injector (HLI).The new linac should feed the GSI flagship experiments SHIP and TASCA, as well as material research, biophysics and plasma physics experiments in the MeV/u-area. The linac will be integrated in the GSI-UNILAC-environment; it is housed by the existing constructions. Different layout scenarios of a multipurpose high intensity heavy ion facility will be presented as well as the schedule for preparation and integration of the new cw-linac.

TUPB075

Beam Dynamics Design of China ADS Proton Linac

linac, emittance, rfq, proton

648

Z. Li, P. Cheng, H. Geng, Z. Guo, C. Meng, B. Sun, J.Y. Tang, F. Yan
IHEP, Beijing, People's Republic of China

Funding: Supported by China ADS Program(XDA03020000), National Natural Science Fundation of China (10875099) and IHEP Special Fundings(Y0515550U1)
It is widely accepted that the Accelerator Driven System (ADS) is one of the most promising technical approach to solve the problem of the nuclear wastes, a potential threaten to the sustainable development of the nuclear fission energy. An ADS study program is approved by Chinese Academy of Sciences at 2011, which aims to design and built an ADS demonstration facility with the capability of more than 1000 MW thermal power within the following 25 years. The 15 MW driver accelerator will be designed and constructed by the Institute of High Energy Physics(IHEP) and Institute of Modern Physics(IMP) of China Academy of Sciences. This linac is characterized by the 1.5 GeV energy, 10mA current and CW operation. It is composed by two parallel 10 MeV injectors and a main linac integrated with fault tolerance design. The superconducting acceleration structures are employed except the RFQ. In this paper the general considerations and the beam dynamics design of the driver accelerator will be presented.

TUPB092

High Power Amplifier Systems for SARAF Phase II

controls, rf-amplifier, insertion, status

675

B. Kaizer, I. Fishman, I.G. Gertz
Soreq NRC, Yavne, Israel

Soreq NRC initiated the establishment of SARAF - Soreq Applied Research Accelerator Facility. SARAF is based on a continuous wave (CW), proton/deuteron RF superconducting linear accelerator with variable energy (5–40 MeV) and current (0.04-5 mA). RF power to each cavity is driven by a High Power Solid State Amplifiers. The paper outlines the design concept of the 10 and 15 kW at 176 MHz power amplifiers that were designed, built, and 10 kW successfully tested. 15 kW is now under construction. The amplifiers are combined from basic 5.5 kW compact 19" 7U water cooled drawer.

TUPB093

Compact 4 kW Variable RF Power Coupler for FRIB Quarter-wave Cavities

cryomodule, vacuum, simulation, linac

678

M.P. Kelly, Z.A. Conway, M. Kedzie, S.V. Kutsaev
ANL, Argonne, USA
J.L. Crisp, L.L. Harle
FRIB, East Lansing, Michigan, USA

A new compact 4 kW power coupler has been designed and prototyped at Argonne National Laboratory in collaboration with Michigan State University. The coupler is intended for use on the β=0.085 80.5 MHz superconducting quarter-wave cavities for the FRIB driver linac and also for the planned ReA6 quarter-wave cavity cryomodule. The design has a cold RF window and a 3 cm variable bellows section. The 16 cm overall length of the RF window and bellows facilitates a simple and compact installation onto the cavity inside the clean room. A prototype have been cold tested with high power under realistic conditions at Argonne and results are presented.

TUPB094

High Power Tests of TRASCO RFQ Couplers

vacuum, rfq, simulation, klystron

681

E. Fagotti, L. Antoniazzi, F. Grespan, A. Palmieri, F. Scarpa
INFN/LNL, Legnaro (PD), Italy
O. Brunasso Cattarello, R. Panero
INFN-Torino, Torino, Italy
M. Desmons
CEA/DSM/IRFU, France

The 352.2 MHz 7.13 m long TRASCO RFQ requires an overall amount of 900 kW CW RF power in order to deliver the 40 mA proton beam from the initial energy of 80 keV to the final energy of 5 MeV. For such a purpose a system of eight compact (ϕext=38 mm, ϕint=19.4 mm) loop-based couplers was designed. In a first phase, only the first two (out of six) modules of the RFQ were tested at full power. Therefore only two (out of eight) couplers were used. In order to completely characterize these couplers, a dedicated test bench was prepared, consisting of a bridge waveguide and diagnostics (reflected power, vacuum, arc detectors etc.), onto which a couple of couplers was connected for transmission measurements. Each coupler was tested with a forward power of up to 140 kW. The description of the experimental setup and procedure, as well as the main results of the conditioning procedure will be reported in this paper.

TUPB095

Design of Coupler for Direct Coupled Amplifier to Drift Tube Linac Cavities of the Injector RILAC2 for RIKEN RI Beam Factory

impedance, DTL, coupling, linac

684

K. Suda, S. Arai, Y. Chiba, O. Kamigaito, M. Kase, H. Okuno, N. Sakamoto, Y. Watanabe, K. Yamada
RIKEN Nishina Center, Wako, Japan

A new linac RILAC2 was constructed at RIKEN RI Beam Factory as an injector for very heavy ions such as uranium and xenon of a high mass to charge ratio m/q ∼ 7, but high intensity ions can be extracted from an ion source. Three drift tube linac cavities, operate in continuous wave mode at 36.5 MHz, have been designed and built. In order to reduce an installation area, and to save a construction cost, we adopted a direct coupling method for a power amplifier without using a long transmission line. A complicated design procedure was performed in order to take into account a change of resonant frequency of the cavity caused by a capacitance of a power tube used in the amplifier. A design of the coupler, as well as the cavity was performed using a three-dimensional electromagnetic calculation code, CST Microwave Studio (MWS). The measured input impedance seen from the amplifier (700 – 1100 Ω) was reproduced well by the calculation of MWS. Also, in order to examine MWS, a case of a coupling with 50 Ω were calculated. The coupling conditions obtained by MWS were compared with the measurement and a calculation with a lumped circuit model.

TUPB097

The C-band RF Pulse Compression for Soft XFEL at SINAP

coupling, simulation, klystron, free-electron-laser

687

C.P. Wang, Q. Gu, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

A compact soft X-ray free electron laser facility is presently being constructed at shanghai institute of applied physics (SINAP), Chinese academy of science in 2012 and will be accomplished in 2014. This facility requires a compact linac with a high-gradient accelerating structure for a limited overall length less than 230 m. The c-band technology which is already used in KEK/Spring-8 linear accelerator is a good compromise for this compact facility and a c-and traveling-wave accelerating structure was already fabricated and tested at SINAP, so a c-band pulse compression will be required. AND a SLED type RF compression scheme is proposed for the C-band RF system of the soft XFEL and this scheme uses TE0.1.15 mode energy storage cavity for high Q-energy storage. The C-band pulse compression under development at SINAP has a high power gain about 3.1 and it is designed to compress the pulse width from 2.5 μs to 0.5 μs and multiply the input RF power of 50 MW to generate 160 MW peak RF power, and the coupling coefficient will be 8.5. It has three components: 3 dB coupler, mode convertors and the resonant cavities.

TUPB099

Input Coupler of the J-PARC DTL

coupling, DTL, vacuum, linac

690

F. Naito, K. Nanmo, H. Tanaka
KEK, Ibaraki, Japan
K. Hirano, T. Ito
JAEA/J-PARC, Tokai-mura, Japan

Each tank of J-PARC DTL has two input couplers. The coupler has a movable coupling　loop with an capacitive element which increase the coupling with the tank. The loop position is the outside of the tank, where is the atmosphere. The tank vacuum is kept by the ceramic window on the wall for the coupler port. The ceramic is made of Aluminum oxide of 99.7 % purity. RF properties and the mechanical structure of the coupler were designed adequately in order to achieve the desired performance. We will report the design of the coupler in detail and the experiences for the practical operation of the DTL.

TUPB100

Recovery and Status Report of DTL/SDTL for the J-PARC After Earthquake

DTL, alignment, linac, target

693

T. Ito, K. Hirano
JAEA/LINAC, Ibaraki-ken, Japan
F. Naito, K. Nanmo
KEK, Ibaraki, Japan

The J-PARC facilities had big damages because of the earthquake on March 11, 2011. The J-PARC linac in the tunnel had also damages. For instance the alignment of the cavity was deformed more than 40 mm and there had been observed about 0.2 mm in horizontal direction for a few DTs in the DTL. However, as the result of the recovery work which includes the re-alignment and re-conditioning of whole cavities, we were able to restart the beam acceleration of the linac. The stability of the DTL and SDTL has returned to the state before the earthquake except for a few tanks of SDTL. In this paper, we will present the recovery works from the earthquake and the operating status of the DTL and the SDTL.

TUPB101

Beam Loss Occurred at DTL Cavity in J-PARC Linac

DTL, radiation, linac, drift-tube-linac

696

A. Miura, K. Hirano, T. Ito, T. Maruta
JAEA/J-PARC, Tokai-mura, Japan
M. Ikegami
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
T. Miyao, F. Naito, K. Nanmo
KEK, Ibaraki, Japan

The beam operation of J-PARC linac was suspended until December 2011 due to the damage by the Tohoku earthquake in March 2011. After resumed the operations, we measured the residual radiation along with the beam line during a short interval. Because the higher residual radiation was detected at the surface of drift tube linac (DTL) cavity by radiation survey, we installed the scintillation beam loss monitors (BLM) at the points where the higher radiation was detected to understand the cause of the radiation. Even the DTL section is low energy part of the linac, fine structure of the beam loss was observed by the scintillation BLM. And we measured the beam loss occurred at the DTL with the parameters of beam orbit and cavity settings. Also, the BLM is employed for the linac tuning. In this paper, the result of the radiation measurement and beam loss signals obtained by the scintillation BLMs are presented.

TUPB103

CSNS DTL Prototyping and RF Tuning

DTL, linac, vacuum, quadrupole

702

H.C. Liu, Q. Chen, S. Fu, K.Y. Gong, A.H. Li, J. Peng, Y.C. Xiao, X. Yin
IHEP, Beijing, People's Republic of China

The 324 MHz Alvarez-type Drift Tube Linac (DTL) for the China spallation neutron source will be used to accelerate the H⁻ ion beam of up to 15 mA peak current from 3 to 80 MeV. It consists of four independent tanks, of which the average length is about 8.6 m. Each tank is divided into three short unit tanks about 2.8 m in length for easy manufacture. A full-scale prototype of the first unit tank with 28 drift tubes containing electromagnetic quadrupoles has been constructed to validate the design and to demonstrate the technology. The overall features of the prototype in both key technology and RF tuning are presented. In particular, the influence of the post couplers was studied in the ramped field DTL.

TUPB107

Amplitude and Phase Control of the Accelerating Field in the ESS Spoke Cavity

controls, feedback, beam-loading, simulation

708

V.A. Goryashko, R.J.M.Y. Ruber, R.A. Yogi, V.G. Ziemann
Uppsala University, Uppsala, Sweden

We report about numerical simulations of the accelerating field dynamics in the ESS spoke cavity in the presence of the beam loading and Lorentz detuning. A slow feedforward is used to cure the Lorentz detuning whereas a fast feedback through a signal oscillator and cavity pre-detuning technique are applied to eliminate the beam loading effect. An analysis performed with a Simulink model shows that a combination of feedforward, feedback and cavity pre-detuning result in a substantially shorter stabilization time of the field voltage and phase on a required level as compared to a control method using only the feedforward and feedback. The latter allows one to obtain smaller magnitude but longer duration of deviations of the instantaneous voltage and phase from the required nominal values. As a result, a series of cavities only with feedforward and feedback needs an extra control technique to mitigate a cumulative systematic error rising in each cavity. In addition, a technique of adiabatic turning off of the RF power in order to prevent a high reflected power in the case of a sudden beam loss is studied.

WE1A04

The ARIEL Superconducting Electron Linac

cryomodule, gun, TRIUMF, linac

729

S.R. Koscielniak, F. Ames, R.A. Baartman, I.V. Bylinskii, Y.-C. Chao, D. Dale, R.J. Dawson, E.R. Guetre, N. Khan, A. Koveshnikov, A. Laxdal, R.E. Laxdal, F. Mammarella, M. Marchetto, L. Merminga, A.K. Mitra, T. Planche, Y.-N. Rao, A. Sitnikov, V.A. Verzilov, D. Yosifov, V. Zvyagintsev
TRIUMF, Vancouver, Canada
D. Karlen, R.R. Langstaff
Victoria University, Victoria, B.C., Canada

The TRIUMF Advanced Rare Isotope Laboratory (ARIEL) is funded since 2010 June by federal and BC Provincial governments. In collaboration with the University of Victoria, TRIUMF is proceeding with construction of a new target building, connecting tunnel, rehabilitation of an existing vault to contain the electron linear accelerator, and a cryogenic compressor building. TRIUMF starts construction of a 300 keV thermionic gun, and 10 MeV Injector cryomodule (EINJ) in 2012; the designs being complete. The 25 MeV Accelerator Cryomodule (EACA) follows in autumn 2013. TRIUMF is embarking on major equipment purchases and has signed contracts for 4K cryogenic plant and four sub-atmospheric pumps, a 290 kW c.w. klystron and high-voltage power supply, 80 quadrupole magnets, EINJ tank and lid, and four 1.3 GHz niobium 9-cell cavities from a local Canadian supplier. The low energy beam transport and beam diagnotics are being installed at the ISAC-II/VECC test facility. Procurement is anticipated October 2012 for the liquid He distribution system.

Slides WE1A04 [4.305 MB]

TH1A01

Results Achieved by the S1-Global Collaboration for ILC

cryomodule, controls, feedback, LLRF

748

H. Hayano, M. Akemoto, S. Fukuda, K. Hara, N. Higashi, E. Kako, H. Katagiri, Y. Kojima, Y. Kondo, T. Matsumoto, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, N. Ohuchi, T. Saeki, T. Shidara, T. Shishido, T. Takenaka, A. Terashima, N. Toge, K. Tsuchiya, K. Watanabe, S. Yamaguchi, A. Yamamoto, Y. Yamamoto, K. Yokoya
KEK, Ibaraki, Japan
C. Adolphsen, C.D. Nantista
SLAC, Menlo Park, California, USA
T.T. Arkan, S. Barbanotti, M.A. Battistoni, H. Carter, M.S. Champion, A. Hocker, R.D. Kephart, J.S. Kerby, D.V. Mitchell, T.J. Peterson, Y.M. Pischalnikov, M.C. Ross, W. Schappert, B.E. Smith
Fermilab, Batavia, USA
A. Bosotti, R. Paparella, P. Pierini
INFN/LASA, Segrate (MI), Italy
K. Jensch, D. Kostin, L. Lilje, A. Matheisen, W.-D. Möller, P. Schilling, M. Schmökel, N.J. Walker, H. Weise
DESY, Hamburg, Germany
C. Pagani
Università degli Studi di Milano & INFN, Segrate, Italy

The S1-Global collaboration (scope and plans presented at Linac10) ended successfully in 2011. In the S1-Global experiment several variants of ILC components (e.g. cavities, tuners, modules, couplers) proposed by all SCRF collaborators worldwide have been extensively tested and their performances compared, in order to build consensus for the technical choices towards the ILC TDR and to develop further the concept of plug-compatible components for ILC. The experiment has been carried at KEK with contribution of hardware and manpower from all collaborators.

Slides TH1A01 [6.656 MB]

TH1A02

Compact Superconducting Crabbing and Deflecting Cavities

dipole, HOM, damping, collider

753

S.U. De Silva
ODU, Norfolk, Virginia, USA
S.U. De Silva
JLAB, Newport News, Virginia, USA

Recently, new geometries for superconducting crabbing and deflecting cavities have been developed that have significantly improved properties over those the standard TM110 cavities. They are smaller, have low surface fields, high shunt impedance and, more importantly for some of them, no lower-order-mode with a well-separated fundamental mode. This talk will present the status of the development of these cavities.

Slides TH1A02 [3.811 MB]

TH1A03

Superconducting Spoke Cavities for Electron and High-Velocity Proton Linacs

linac, impedance, SRF, electron

758

J.R. Delayen
ODU, Norfolk, Virginia, USA

Spoke resonantors are currently under development for many proton machines but these structures are also considered for high beta electron linacs as well. These structures compare well to traditional elliptical cavities.

Slides TH1A03 [3.570 MB]

TH1A04

Superconducting Linac and Associated Developments at IUAC Delhi

linac, ion, rfq, ECR

763

A. Roy
IUAC, New Delhi, India

A superconducting linear accelerator system consisting of a series of independently phase locked niobium quarter wave resonators has been developed as a booster of heavy ion beams available from the existing 15UD Pelletron accelerator. Two superconducting linac booster modules having eight niobium quarter wave resonators (QWRs) each have been installed and are fully operational for regular scheduled experiments. The third module is being added to the system. A new high current injector has been planned to couple to the superconducting linac. For this a high temperature superconducting electron cyclotron resonance ion source (HTS-ECRIS) was designed, fabricated and installed successfully. A radio frequency quadrupole (RFQ) accelerator is being developed for accelerating accelerate ions from the ECR (A/Q ~ 6) to an energy to of about 180 keV/A. The beams will then be accelerated further by drift tube linacs (DTL) to the required velocity to inject them to the existing superconducting linac booster. Prototypes of both these have been tested for power and thermal studies. Details of these developments and associated systems will be presented.

Slides TH1A04 [7.830 MB]

TH2A01

The ESS Linac Design

linac, klystron, cryomodule, proton

768

M. Lindroos, H. Danared, C. Darve, D.P. McGinnis, S. Molloy
ESS, Lund, Sweden

The European Spallation Source (ESS) is a 5 MW, 2.5 MeV long pulse proton machine. It represents a big jump in power compare to the existing spallation facilities. The design phase is well under way, with the delivery of a Conceptual Design Report expected in 2012, and a Technical Design Report in 2013. Why and how the 5 MW goal influences the parameter choice will be describe.

Slides TH2A01 [5.667 MB]

TH2A03

Design and Construction of the Linac4 Accelerating Structures

linac, DTL, rfq, vacuum

778

F. Gerigk, Y. Cuvet, A. Dallocchio, G. Favre, J.-M. Geisser, L. Gentini, J.-M. Giguet, S.J. Mathot, M. Polini, S. Ramberger, B. Riffaud, C. Rossi, P. Ugena Tirado, M. Vretenar, R. Wegner
CERN, Geneva, Switzerland
E. Kendjebulatov, Ya.G. Kruchkov, A.G. Tribendis
BINP SB RAS, Novosibirsk, Russia
M.Y. Naumenko
RFNC-VNIITF, Snezhinsk, Chelyabinsk region, Russia

The Linac4 project at CERN is at an advanced state of construction. Prototypes of the different types of accelerating structures (RFQ, DTL, CCDTL and pi-mode structures) have been built and are presently tested. This paper gives the status of the cavity production and reviews the RF and mechanical design of the various structure types. Furthermore the production and the first test results shall be presented.

Slides TH2A03 [2.675 MB]

TH3A01

Status of ILC

cryomodule, HLRF, linac, linear-collider

787

A. Yamamoto
KEK, Ibaraki, Japan
M.C. Ross
SLAC, Menlo Park, California, USA
N.J. Walker
DESY, Hamburg, Germany

A review of the ILC project with emphasis on the changes in the technical progress report.

Slides TH3A01 [5.396 MB]

TH3A02

The 12 GeV Energy Upgrade at Jefferson Laboratory

cryomodule, linac, collider, electron

792

F.C. Pilat
JLAB, Newport News, Virginia, USA

Two new cryomodules and an extensive upgrade of the bending magnets at Jefferson Lab has been recently completed in preparation for the full energy upgrade in about one year.

Slides TH3A02 [3.482 MB]

THPLB01

Linac Construction for China Spallation Neutron Source

linac, DTL, rfq, neutron

807

S. Fu, J. Li, H.C. Liu, H.F. Ouyang, X. Yin
IHEP, Beijing, People's Republic of China

Construction of China Spallation Neutron Source(CSNS) has been launched in September 2011. CSNS accelerator will provide 100kW proton beam on a target at beam energy of 1.6GeV. It consists of an 80MeV H⁻ linac and 1.6GeV rapid cycling synchrotron. Based on the prototyping experience, CSNS linac, including the front end and four DTL tanks, has finalized the design and started procurement. In this paper, we will first present an outline of the CSNS accelerator in its design and construction plan. Then the major prototyping results of the linac will be presented. Finally the linac construction progress in recent will be updated.

Slides THPLB01 [1.969 MB]

THPLB02

Performance of Ferrite Vector Modulators in the LLRF system of the Fermilab HINS 6-Cavity Test

controls, klystron, rfq, LLRF

810

P. Varghese, B.W. Barnes, B. Chase, E. Cullerton, C.C. Tan
Fermilab, Batavia, USA

The High Intensity Neutrino Source (HINS) 6-cavity test is a part of the Fermilab HINS Linac R&D program for a low energy, high intensity proton/H⁻ linear accelerator. One of the objectives of the 6-cavity test is to demonstrate the use of high power RF Ferrite Vector Modulators(FVM) for independent control of multiple cavities driven by a single klystron. The beamline includes an RFQ and six cavities. The LLRF system provides a primary feedback loop around the RFQ and the distribution of the regulated klystron output is controlled by secondary learning feed-forward loops on the FVMs for each of the six cavities. The feed-forward loops provide pulse to pulse correction to the current waveform profiles of the FVM power supplies to compensate for beam-loading and other disturbances. The learning feed-forward loops are shown to successfully control the amplitude and phase settings for the cavities well within the 1 % and 1 degree requirements specified for the system.

Slides THPLB02 [1.610 MB]

THPLB05

R&D Activities on High Intensity Superconducting Proton Linac at RRCAT

SRF, ion, niobium, linac

819

S.C. Joshi, J. Dwivedi, P.D. Gupta, P.R. Hannurkar, P. Khare, P.K. Kush, G. Mundra, A. Puntambekar, S.B. Roy, P. Shrivastava
RRCAT, Indore (M.P.), India

Raja Ramanna Centre for Advanced Technology (RRCAT), Indore has taken up a program on development of 1 GeV high intensity superconducting proton linac for Spallation Neutron Source. This will require several multi-cell superconducting cavities operating at different RF frequencies. To start with, a number of single-cell prototype cavities at 1.3 GHz have been developed in high RRR bulk niobium. These single-cell cavities have exhibited high quality factor and accelerating gradients. Superconducting properties of niobium are being studied for varying composition of impurities and different processing conditions. Development activity on solid state RF amplifiers to power the SCRF cavities at various RF frequencies is being pursued. A building has been constructed to house the SCRF cavity fabrication and processing facility. To characterize SCRF cavity, a 2 K Vertical Test Stand is being set up including a 2 K cryostat, RF power supply and data acquisition system. Design activities for cryomodule and large 2 K cryostat for Horizontal Test Stand are also under progress. The paper will discuss the status of above R&D activities and infrastructure development at RRCAT.

Slides THPLB05 [1.614 MB]

THPLB08

High-Power RF Conditioning of the TRASCO RFQ

rfq, controls, vacuum, pick-up

828

E. Fagotti, L. Antoniazzi, F. Grespan, A. Palmieri
INFN/LNL, Legnaro (PD), Italy
M. Desmons
CEA/DSM/IRFU, France

The TRASCO RFQ is designed to accelerate a 40 mA proton beam up to 5 MeV. It is a CW machine which has to show stable operation and provide the requested availability. It is composed of three electromagnetic segment coupled via two coupling cells. Each segment is divided into two 1.2 m long OFE copper modules. The RFQ is fed through eight loop-based power couplers to deliver RF to the cavity from a 352.2 MHZ, 1.3 MW klystron. After couplers conditioning, the first electromagnetic segment was successfully tested at full power. RFQ cavity reached the nominal 68 kV inter-vane voltage (1.8 Kilp.) in CW operation. Moreover, during conditioning in pulsed operation, it was possible to reach 83 kV inter-vane voltage (2.2 Kilp.) with a 1% duty cycle. The description of the experimental setup and procedure, as well as the main results of the conditioning procedure will be reported in this paper.

Slides THPLB08 [1.384 MB]

THPLB09

Status of E-XFEL String and Cryomodule Assembly at CEA-Saclay

cryomodule, vacuum, controls, synchrotron

831

C. Madec
CEA, Gif-sur-Yvette, France
S. Berry, J.-P. Charrier, A. Daël, M. Fontaine, Y. Gasser, O. Napoly, Y. Sauce, C.S. Simon, T.V. Vacher, B. Visentin
CEA/DSM/IRFU, France
A. Brasseur, P. Charon, C. Cloué, S. Langlois, G. Monnereau, J.L. Perrin, D. Roudier, N. Sacépé
CEA/IRFU, Gif-sur-Yvette, France

As In-Kind contributor to E-XFEL project, CEA is committed to the integration on the Saclay site of the 100 cryomodules of the superconducting linac as well as to the procurement of the magnetic shieldings, superinsulation blankets and 31 cold beam position monitors of the re-entrant type. The assembly infrastructure has been renovated from the previous Saturne Synchrotron Laboratory facility: it includes a 200 m² clean room complex with 120 m² under ISO4, 1325 m² of assembly platforms and 400 m² of storage area. In parallel, CEA has conducted industrial studies and three cryomodule assembly prototyping both aiming at preparing the industrial file, the quality management system and the commissioning of the assembly plant, tooling and control equipments. In 2012, the contract of the integration will be placed to a subcontractor. The paper will summarize the outputs of the preparation and prototyping phases and the up-coming industrial phase.

THPLB12

Photoinjector SRF Cavity Development for BERLinPro

cathode, gun, HOM, emittance

837

A. Neumann, W. Anders, T. Kamps, J. Knobloch
HZB, Berlin, Germany
E.N. Zaplatin
FZJ, Jülich, Germany

In 2010 HZB has received approval to build BERLinPro, an ERL project to demonstrate energy recovery at 100 mA beam current by pertaining a high quality beam. These goals place stringent requirements on the SRF cavity for the photoinjector which has to deliver a small emittance 100 mA beam with at least 1.5 MeV kinetic energy while limited by fundamental power coupler performance to about 200 kW forward power. In oder to achieve these goals the injector cavity is being developed in a three stage approach. The current design studies focus on implementing a normal conducting cathode insert into a newly developed superconducting photoinjector cavity. In this paper the fundamental RF design calculations concerning cell shape for optimized beam dynamics as well as SRF performance will be presented. Further studies concentrate on the HZDR based choke cell design to implement the high quantum efficiency normal conducting cathode with the SRF cavity.

Slides THPLB12 [1.431 MB]

THPB003

R&D Activities on High Intensity Superconducting Proton Linac at RRCAT

SRF, ion, niobium, linac

843

S.C. Joshi, J. Dwivedi, P.D. Gupta, P.R. Hannurkar, P. Khare, P.K. Kush, G. Mundra, A. Puntambekar, S.B. Roy, P. Shrivastava
RRCAT, Indore (M.P.), India

Raja Ramanna Centre for Advanced Technology (RRCAT), Indore has taken up a program on development of 1 GeV high intensity superconducting proton linac for Spallation Neutron Source. This will require several multi-cell superconducting cavities operating at different RF frequencies. To start with, a number of single-cell prototype cavities at 1.3 GHz have been developed in high RRR bulk niobium. These single-cell cavities have exhibited high quality factor and accelerating gradients. Superconducting properties of niobium are being studied for varying composition of impurities and different processing conditions. Development activity on solid state RF amplifiers to power the SCRF cavities at various RF frequencies is being pursued. A building has been constructed to house the SCRF cavity fabrication and processing facility. To characterize SCRF cavity, a 2 K Vertical Test Stand is being set up including a 2 K cryostat, RF power supply and data acquisition system. Design activities for cryomodule and large 2 K cryostat for Horizontal Test Stand are also under progress. The paper will discuss the status of above R&D activities and infrastructure development at RRCAT.

THPB006

Post Acceleration of Laser-generated Proton Bunches by a CH-DTL

proton, linac, laser, DTL

852

A. Almomani, M. Droba, I. Hofmann, U. Ratzinger
IAP, Frankfurt am Main, Germany

Laser driven proton beam sources applying the TNSA process show interesting features in terms of energy and proton number per bunch. This makes them attractive as injectors into RF linacs at energies as high as 10 MeV or beyond. The combination shows attractive features like a very high particle number in a single bunch from the source and the flexibility and reliability of the rf linac to match the needs of a specified application. The approach aims on a very short matching section from the source target into the rf linac by one pulsed solenoid lens only. A crossbar H-type (CH - structure) is suggested because of its high acceleration gradient and efficiency at these beam energies. It is intended to realize the first cavity of the proposed CH - linac and to demonstrate the acceleration of a laser generated proton bunch within the LIGHT collaboration at GSI Darmstadt. Detailed beam and field simulations will be presented.

THPB008

A Coupled RFQ-IH Cavity for the Neutron Source FRANZ

rfq, DTL, coupling, simulation

858

M. Heilmann, O. Meusel, D. Mäder, U. Ratzinger, A. Schempp, M. Schwarz
IAP, Frankfurt am Main, Germany

The Frankfurt neutron source FRANZ will deliver neutrons in the energy range from 1 to 500 keV with high pulsed intensities. A 2 MeV proton beam will produce protons via the 7Li(p,n)7Be reaction. The 175 MHz accelerator cavity consists of a 4-rod-RFQ coupled with an 8 gap interdigital H-type drift tube section, the total cavity length being 2.3m. The combined cavity will be powered by one RF amplifier to reduce investment and operation costs. The inductive power coupler will be at the RFQ part. The coupling into the IH - section is provided through a large aperture - mainly inductively. By CST - MWS - simulations as well as by an RF - model the voltage tuning along the cavity was investigated, and with special care the balance between both cavity sections. A first set of RFQ electrodes should allow to reach beam currents up to 50 mA in cw operation: The beam is pulsed with 100 ns, 250 kHz, while the cavity has to be operated cw due to the high rep. rate. The layout of the cavity cooling aims on a maximum accessible heat load of 200 kW.

THPB009

Status of CH Cavity and Solenoid Design of the 17 MeV Injector for MYRRHA

solenoid, focusing, rfq, quadrupole

861

D. Mäder, H. Klein, H. Podlech, U. Ratzinger, C. Zhang
IAP, Frankfurt am Main, Germany

Funding: This work has been supported by the EU (FP7 MAX contract number 269565)
The multifunctional subcritical reactor MYRRHA (Multi-purpose hybrid research reactor for high-tech applications) will be an accelerator driven system (ADS) located in Mol (Belgium). The first accelerating section up to 17 MeV is operated at 176 MHz and consists of a 4-rod-RFQ followed by two room temperature CH cavities with integrated triplet lenses and four superconducting CH structures with intertank solenoids. Each room temperature CH cavity provides about 1 MV effective voltage gain using less than 30 kW of RF power. The superconducting resonators have been optimized for electric peak fields below 30 MV/m and magnetic peak fields below 30 mT. For save operation of the superconducting resonators the magnetic field of the intertank solenoids has to be well shielded towards the CH cavity walls. Different coil geometries have been compared to find the ideal solenoid layout.

THPB015

Performance of Ferrite Vector Modulators in the LLRF system of the Fermilab HINS 6-Cavity Test

controls, klystron, rfq, LLRF

879

P. Varghese, B.W. Barnes, B. Chase, E. Cullerton, C.C. Tan
Fermilab, Batavia, USA

The High Intensity Neutrino Source (HINS) 6-cavity test is a part of the Fermilab HINS Linac R&D program for a low energy, high intensity proton/H⁻ linear accelerator. One of the objectives of the 6-cavity test is to demonstrate the use of high power RF Ferrite Vector Modulators(FVM) for independent control of multiple cavities driven by a single klystron. The beamline includes an RFQ and six cavities. The LLRF system provides a primary feedback loop around the RFQ and the distribution of the regulated klystron output is controlled by secondary learning feed-forward loops on the FVMs for each of the six cavities. The feed-forward loops provide pulse to pulse correction to the current waveform profiles of the FVM power supplies to compensate for beam-loading and other disturbances. The learning feed-forward loops are shown to successfully control the amplitude and phase settings for the cavities well within the 1 % and 1 degree requirements specified for the system.

THPB020

Annular-ring Coupled Structure for the Energy Upgrade of the J-PARC Linac

linac, vacuum, coupling, target

888

H. Ao, H. Asano, N. Ouchi, J. Tamura
JAEA/J-PARC, Tokai-mura, Japan
F. Naito, K. Takata
KEK, Ibaraki, Japan

The linac of Japan Proton Accelerator Research Complex (J-PARC), which is an injector to the synchrotron, comprises a 3-MeV RFQ, 50-MeV DTLs and the 181-MeV Separated-type DTLs. In order to increase the beam power of the synchrotron, the task of the 400-MeV energy upgrade of the linac started from March 2009. The tanks of the Annular-ring Coupled Structure (ACS) linac, RF sources, beam monitors and utilities are in production. Although some peripheral components of the ACS linac are prepared previously, the all ACS tanks will be installed and conditioned for 4 months from July 2013. Beam commissioning of the 400-MeV linac is scheduled to begin in October and expected to finish at the end of November 2013. In this paper, we present the current status of the energy upgrade and some R&D results for new equipment for ACS linac.

THPB023

Linac Construction for China Spallation Neutron Source

linac, DTL, rfq, neutron

897

S. Fu, J. Li, H.C. Liu, H.F. Ouyang, X. Yin
IHEP, Beijing, People's Republic of China

Construction of China Spallation Neutron Source(CSNS) has been launched in September 2011. CSNS accelerator will provide 100kW proton beam on a target at beam energy of 1.6GeV. It consists of an 80MeV H⁻ linac and 1.6GeV rapid cycling synchrotron. Based on the prototyping experience, CSNS linac, including the front end and four DTL tanks, has finalized the design and started procurement. In this paper, we will first present an outline of the CSNS accelerator in its design and construction plan. Then the major prototyping results of the linac will be presented. Finally the linac construction progress in recent will be updated.

THPB024

Main Linac Physics Design Study of the C-ADS Project

linac, emittance, solenoid, lattice

900

F. Yan, Z. Li, C. Meng, J.Y. Tang
IHEP, Beijing, People's Republic of China

Funding: The pilot special funds of Chinese Academy of Science
The Chinese ADS project is proposed to build a 1000MW Accelerator Driven sub-critical System before 2032. The accelerator will be operating on CW mode with 10mA average current and the final energy is 1.5GeV. The whole linac are composed of two major sections: the Injector section and the main linac section. There are two different schemes for the Injector section. InjectorI is basing on 325MHz RFQ and superconducting spoke cavities and Injector II is basing on 162.5MHz RFQ and superconducting HWR cavities. The main linac design will be different for different Injector choice. If Injector II scheme is adopted, the main linac bunch current will be doubled. In this paper we studied the main linac design basing on InjectorII scheme. The design principles and the priliminary design results is presented.

THPB025

325 MHz CW Room Temperature High Power Bunching Cavity for the China ADS MEBT1

bunching, impedance, vacuum, resonance

903

S. Pei, X. Li, H.F. Ouyang, J.R. Zhang
IHEP, Beijing, People's Republic of China

Two room temperature high power bunching cavities are required to be located in the ADS MEBT1 section. Double re–entrant nose cone geometry has been adopted as the type of the bunching cavity for its simplicity, higher shunt impedance and lower risk of multipacting. SUPERFISH is used to optimize the internal dimensions of the bunching cavity, then the RF–thermal–structural–RF coupled analysis were carried out in ANSYS to obtain the preliminary mechanical design, the layout of the cooling channels is optimized to suppress the frequency shift as much as possible. The cavity was specially designed to have the capability to withstand the 1 atm air pressure effect. In addition, the main dimensions of the coupler and tuner are also estimated.
*peisl@ihep.ac.cn

THPB026

The Beam Commissioning Plan of Injector II in C-ADS

rfq, proton, simulation, diagnostics

906

Z.J. Wang, Y. He, H. Jia, C. Li, S.H. Liu, W. Wu, X.B. Xu, B. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

The design work of the Injector II, which is 10 MeV proton linac, in C-ADS project is being finished and some key elements are being fabricated. Now it is necessary to definite the operation mode of beam commissioning, including the selection of the beam current, pulse length and repetition frequency. Also the beam commissions plan should be specified. The beam commissions procedures is simulated with t-mode code GPT. In this paper, the general beam commissioning plan of Injector II in CIADS and simulation results of commissions procedures are presented.

THPB027

Progress of one of 10 MeV superconducting proton linear Injectors for C-ADS

rfq, linac, proton, niobium

909

Y. He, J. Meng, A. Shi, Z.J. Wang, J.X. Wu, W. Wu, H.S. Xu, Z. Xu, B. Zhang, J.H. Zhang, S.H. Zhang, Z.M. Zhang, H.W. Zhao, Z.Z. Zhou
IMP, Lanzhou, People's Republic of China
D. Li
LBNL, Berkeley, California, USA

A 10 MeV superconducting proton linac is being design and constructing at Institute of Modern Physics (IMP) of Chinese Academy of Sciences (CAS). This proton linac is one of two injectors for Chinese ADS project. It is to validate one of concepts for C-ADS front end, to demonstrate the low beta acceleration, to minimize the risk of key technoledges within the Reference Design. It consists of a 2.1 MeV RFQ and two cryomodules hosting 8 HWR cavities. The basic frequecy is 162.5 MHz. The physical design of linac and the progess of prototypes for solid state amplifiers, superconducting solenoids, supercondecting HWRs, ion source, and RFQ are presented in the paper.

THPB032

Beam Dynamics Design Aspects for a Proposed 800 MeV H⁻ ISIS Linac

linac, DTL, quadrupole, rfq

924

D.C. Plostinar, C.R. Prior, G.H. Rees
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom

Several schemes have been proposed to upgrade the ISIS Spallation Neutron Source at Rutherford Appleton Laboratory (RAL). One scenario is to develop a new 800 MeV, H⁻ linac and a ~3 GeV synchrotron, opening the possibility of achieving several MW of beam power. In this paper the design of the 800 MeV linac is outlined with an emphasis on the beam dynamics design philosophy. The linac consists of a 3 MeV Front End similar to the one now under construction at RAL (the Front End Test Stand -FETS). Above 3 MeV, a 324 MHz DTL will be used to accelerate the beam up to ~75 MeV. At this stage a novel collimation system will be added to remove the halo and the far off-momentum particles. To achieve the final energy, a 648 MHz superconducting linac will be employed using three families of elliptical cavities with transition energies at ~196 MeV and ~412 MeV.

THPB034

Status of the FAIR 70 MeV Proton Linac

proton, linac, rfq, DTL

927

L. Groening, W.A. Barth, R. Berezov, G. Clemente, P. Forck, R. Hollinger, A. Krämer, C. Mühle, J. Pfister, G. Schreiber, J. Trüller, W. Vinzenz, C. Will
GSI, Darmstadt, Germany
N. Chauvin, O. Delferrière, O. Tuske
CEA/IRFU, Gif-sur-Yvette, France
B. Koubek, H. Podlech, U. Ratzinger, A. Schempp, R. Tiede
IAP, Frankfurt am Main, Germany
B. Launé, J. Lesrel
IPN, Orsay, France
C.S. Simon
CEA/DSM/IRFU, France

To provide the primary proton beam for the FAIR anti-proton research program, a 70 MeV, 70 mA linac is currently under design & construction at GSI. The nc machine comprises an ECR source, a 3 MeV RFQ, and a DTL based on CH-cavities. Up to 36 MeV pairs of rf-coupled cavities (CCH) are used. A prototype cavity has been built and is prepared for high power rf-testing. An overview of the status as well as on the perspectives of the project is given.

THPB038

Assembly and RF Tuning of the Linac4 RFQ at CERN

rfq, quadrupole, dipole, linac

939

C. Rossi, A. Dallocchio, J. Hansen, J.-B. Lallement, A.M. Lombardi, S.J. Mathot, D. Pugnat, M.A. Timmins, G. Vandoni, M. Vretenar
CERN, Geneva, Switzerland
M. Desmons, A. France, Y. Le Noa, J. Novo, O. Piquet
CEA/DSM/IRFU, France

The fabrication of Linac4 is progressing at CERN with the goal of making a 160 MeV H⁻ beam available to the LHC injection chain as from 2015. In the Linac4 the first stage of beam acceleration, after its extraction from the ion source, is provided by a Radiofrequency Quadrupole accelerator (RFQ), operating at the RF frequency of 352.2 MHz and which accelerates the ion beam to the energy of 3 MeV. The RFQ, made of three modules, one meter each, is of the four-vane kind, has been designed in the frame of a collaboration between CERN and CEA and has been completely machined and assembled at CERN. The paper describes the assembly of the RFQ structure and reports the results of RF low power measurements, in order to achieve the required accelerating field flatness within 1% of the nominal field profile.

THPB039

Design of a Four-Vane RFQ for China ADS Project

rfq, emittance, neutron, proton

942

Z.L. Zhang, X. Du, Y. He, X. Jin, C. Li, Y. Liu, A. Shi, L.P. Sun, B. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China
M.D. Hoff, A.R. Lambert, D. Li, J.W. Staples, S.P. Virostek
LBNL, Berkeley, California, USA
J. Wang
Lanzhou University of Technology, People's Republic of China
C. Zhang
IAP, Frankfurt am Main, Germany

A four-vane RFQ accelerator has been designed for the ADS project which has been launched in China since 2011. As one of the front ends of C-ADS LINAC, the RFQ works at a frequency of 162.5 MHz, accelerating the proton beam from 35 keV to 2.1 MeV. Due to the CW (continuous wave) operating mode, a small Kilpatric factor of 1.2 was adopted. At the same time, Pi-mode rods are employed to reduce the effect of dipole mode on quadrupole mode, and cavity tuning will be implemented by temperature adjustment of cooling water. Beam dynamics design, RF cavity design, thermal and stress analysis all will be presented in the paper.

THPB040

High-Power RF Conditioning of the TRASCO RFQ

rfq, controls, vacuum, pick-up

945

E. Fagotti, L. Antoniazzi, F. Grespan, A. Palmieri
INFN/LNL, Legnaro (PD), Italy
M. Desmons
CEA/DSM/IRFU, France

The TRASCO RFQ is designed to accelerate a 40 mA proton beam up to 5 MeV. It is a CW machine which has to show stable operation and provide the requested availability. It is composed of three electromagnetic segment coupled via two coupling cells. Each segment is divided into two 1.2 m long OFE copper modules. The RFQ is fed through eight loop-based power couplers to deliver RF to the cavity from a 352.2 MHZ, 1.3 MW klystron. After couplers conditioning, the first electromagnetic segment was successfully tested at full power. RFQ cavity reached the nominal 68 kV inter-vane voltage (1.8 Kilp.) in CW operation. Moreover, during conditioning in pulsed operation, it was possible to reach 83 kV inter-vane voltage (2.2 Kilp.) with a 1% duty cycle. The description of the experimental setup and procedure, as well as the main results of the conditioning procedure will be reported in this paper.

THPB042

Production and Quality Control of the First Modules of the IFMIF-EVEDA RFQ

survey, controls, coupling, rfq

948

F. Scantamburlo, R. Dima, A. Pepato
INFN- Sez. di Padova, Padova, Italy
C. Roncolato
INFN/LNL, Legnaro (PD), Italy

The IFMIF/EVEDA RFQ, designed to accelerate a 125mA D⁺ beam from 0.1 MeV to 5 MeV at a frequency of 175 MHz, consists of 18 modules with length of ~550 mm each. The production of the modules has been started and 2 prototype modules plus module 16 have undergone all the production steps, including precision milling and brazing. The progress of the construction and especially the fine tuning of the design and engineering phase are reported.

THPB047

Test RFQ for the MAX Project

rfq, simulation, linac, proton

960

M. Vossberg, H. Klein, H. Podlech, A. Schempp, C. Zhang
IAP, Frankfurt am Main, Germany
A. Bechtold
NTG Neue Technologien GmbH & Co KG, Gelnhausen, Germany

As a part of the MAX project it will be demonstrated by simulations and thermal measurements, that a 4-rod-RFQ is the right choice even at cw-operation. A 4-rod Test-RFQ with a resonance frequency of 175 MHz has been designed and built for the MAX-Project. But the RFQ had to be modified to solve the cooling problem at cw-operation, the geometrical precision had to be improved as well as the rf-contacts. The developments led to a new layout and a sophisticated production procedure of the stems and the electrodes. Calculations show an improved Rp-value leading to powerlosses of ca. 25 kW/m only, which is about half of the powerlosses which could be achieved safely at cw-operation of the similar Saraf-RFQ. Thermal measurements and simulations with the single components are in progress. The temperature distribution in cw-operation will be measured and the rf-performance checked.

THPB062

Multipole Field Effects for the Superconducting Parallel-Bar/RF-Dipole Deflecting/Crabbing Cavities

dipole, multipole, superconductivity, luminosity

981

S.U. De Silva, J.R. Delayen
ODU, Norfolk, Virginia, USA
S.U. De Silva
JLAB, Newport News, Virginia, USA

The superconducting parallel-bar deflecting/crabbing cavity is currently being considered as one of the design options in rf separation for the Jefferson Lab 12 GeV upgrade and for the crabbing cavity for the proposed LHC luminosity upgrade. Knowledge of multipole field effects is important for accurate beam dynamics study of rf structures. The multipole components can be accurately determined numerically using the electromagnetic surface field data in the rf structure. This paper discusses the detailed analysis of those components for the fundamental deflecting/crabbing mode and higher order modes in the parallel-bar deflecting/crabbing cavity.

THPB066

Photoinjector SRF Cavity Development for BERLinPro

cathode, gun, HOM, emittance

993

A. Neumann, W. Anders, T. Kamps, J. Knobloch
HZB, Berlin, Germany
E.N. Zaplatin
FZJ, Jülich, Germany

In 2010 HZB has received approval to build BERLinPro, an ERL project to demonstrate energy recovery at 100 mA beam current by pertaining a high quality beam. These goals place stringent requirements on the SRF cavity for the photoinjector which has to deliver a small emittance 100 mA beam with at least 1.5 MeV kinetic energy while limited by fundamental power coupler performance to about 200 kW forward power. In oder to achieve these goals the injector cavity is being developed in a three stage approach. The current design studies focus on implementing a normal conducting cathode insert into a newly developed superconducting photoinjector cavity. In this paper the fundamental RF design calculations concerning cell shape for optimized beam dynamics as well as SRF performance will be presented. Further studies concentrate on the HZDR based choke cell design to implement the high quantum efficiency normal conducting cathode with the SRF cavity.

THPB069

Beam Dynamics Studies for SRF Photoinjectors

emittance, gun, SRF, booster

999

T. Kamps, A. Neumann, J. Völker
HZB, Berlin, Germany

The SRF photoinjector combines the advantages of photo-assisted production of high brightness, short electron pulses and high gradient, low-loss continuous wave (CW) operation of a superconducting radiofrequency (SRF) cavity. The paper discusses beam dynamics considerations for FEL and ERL class applications of SRF photoinjectors. One case of particular interest is the design of the SRF photoinjector for BERLinPro, an ERL test facility demanding a high brightness beam with an emittance better than 1 mm mrad at 77 pC and average current of 100 mA.

THPB073

Initial RF Tests of the Diamond S-Band Photocathode Gun

gun, cathode, coupling, controls

1002

C. Christou, S.A. Pande
Diamond, Oxfordshire, United Kingdom

An S-band photocathode electron gun designed to operate at repetition rates up to 1 kHz CW has been designed at Diamond and manufactured at FMB*. The first test results of this gun are presented. Low-power RF measurements have been carried out to verify the RF design of the gun, and high-power conditioning and RF test has begun. Initial high power tests have been carried out at 5 Hz repetition rate using the S-band RF plant normally used to power the Diamond linac: the benefits and limitations of this approach are considered, together with plans for further testing.
* J. H. Han et al, NIM A 647(2011) 17-24

THPB079

Development of a Superconducting Focusing Solenoid for CADS

solenoid, focusing, linac, dipole

1011

W. Wu, S.F. Han, Y. He, L.Z. Ma, D.S. Ni, Z.J. Wang, B.M. Wu, W.J. Yang, X.L. Yang, S.J. Zheng, L. Zhu
IMP, Lanzhou, People's Republic of China

A superconducting focusing solenoid has been designed and developed for the China Accelerator Driven System (CADS). In order to meet the requirement of focusing strength and fringe field while minimizing physical size of the solenoid, the novel optimizing design method based on linear programming method was employed. In this report, we will introduce the design of the solenoid including magnetic field optimization, mechanical design and quench protection. The fabrication and the test results of the solenoid will also be introduced in this report.

THPB083

Status of E-XFEL String and Cryomodule Assembly at CEA-Saclay

cryomodule, vacuum, controls, synchrotron

1017

C. Madec
CEA, Gif-sur-Yvette, France
S. Berry, J.-P. Charrier, A. Daël, M. Fontaine, Y. Gasser, O. Napoly, Y. Sauce, C.S. Simon, T.V. Vacher, B. Visentin
CEA/DSM/IRFU, France
A. Brasseur, P. Charon, C. Cloué, S. Langlois, G. Monnereau, J.L. Perrin, D. Roudier, N. Sacépé
CEA/IRFU, Gif-sur-Yvette, France

As In-Kind contributor to E-XFEL project, CEA is committed to the integration on the Saclay site of the 100 cryomodules of the superconducting linac as well as to the procurement of the magnetic shieldings, superinsulation blankets and 31 cold beam position monitors of the re-entrant type. The assembly infrastructure has been renovated from the previous Saturne Synchrotron Laboratory facility: it includes a 200 m² clean room complex with 120 m² under ISO4, 1325 m² of assembly platforms and 400 m² of storage area. In parallel, CEA has conducted industrial studies and three cryomodule assembly prototyping both aiming at preparing the industrial file, the quality management system and the commissioning of the assembly plant, tooling and control equipments. In 2012, the contract of the integration will be placed to a subcontractor. The paper will summarize the outputs of the preparation and prototyping phases and the up-coming industrial phase.

Slides THPB083 [1.868 MB]

THPB084

A Low-Level RF Control System for a Quarter-Wave Resonator

controls, LLRF, resonance, ion

1020

J.-W. Kim, D.G. Kim
IBS, Daejeon, Republic of Korea
C.K. Hwang
KAERI, Daejon, Republic of Korea

A low-level rf control system was designed and built for an rf deflector, which is a quarter wave resonator and was designed to deflect a secondary electron beam to measure the bunch length of an ion beam. The deflector has a resonance frequency at near 88 MHz, and its required phase stability is approximately ±1° and amplitude stability less than ±1%. The control system consists of analog input and output components, and a digital system based on an FPGA for signal processing. It is a cost effective system, while meeting the stability requirements. Some basic properties of the control system were measured. Then the capability of the rf control has been tested using a mechanical vibrator made of a dielectric rod attached to an audio speaker system, which can induce regulated perturbation in the electric fields of the resonator. The control system is flexible such that its parameters can be easily configured to compensate for disturbance induced in the resonator.

THPB085

LLRF Automation for the 9mA ILC Tests at FLASH

controls, feedback, cryomodule, beam-loading

1023

J. Branlard, V. Ayvazyan, O. Hensler, H. Schlarb, Ch. Schmidt, N.J. Walker, M. Walla
DESY, Hamburg, Germany
G.I. Cancelo, B. Chase
Fermilab, Batavia, USA
J. Carwardine
ANL, Argonne, USA
W. Cichalewski, W. Jałmużna
TUL-DMCS, Łódź, Poland
S. Michizono
KEK, Ibaraki, Japan

Since 2009 and under the scope of the International Linear Collider (ILC) R&D, a series of studies takes place twice a year at the Free electron Laser accelerator in Hamburg, (FLASH) DESY, in order to investigate technical challenges related to the high-gradient, high-beam-current design of the ILC. Such issues as operating cavities near their quench limit with high beam loading or in klystron saturation regime are investigated, always pushing the limits of FLASH nominal operational conditions. To support these studies, a series of automation algorithms have been developed and implemented at DESY. These include automatic detection of cavity quenches, automatic adjustment of the superconducting cavity quality factor, and automatic compensation of detuning due to Lorentz forces. This paper explains the functionality of these automation tools, details about their implementation, and shows the experience acquired during the last 9mA ILC test which took place at DESY in February 2012. The benefit of these algorithms and the R&D results these automation tools have permitted will be clearly explained.

THPB086

Precision Regulation of RF Fields with MIMO Controllers and Cavity-based Notch Filters

controls, LLRF, resonance, feedback

1026

Ch. Schmidt, J. Branlard, S. Pfeiffer, H. Schlarb
DESY, Hamburg, Germany
W. Jałmużna
TUL-DMCS, Łódź, Poland

The European XFEL requires a high precision control of the electron beam, generating a specific pulsed laser light demanded by user experiments. The low level radio frequency (LLRF) control system is certainly one of the key players for the regulation of accelerating RF fields. A uTCA standard LLRF system was developed and is currently under test at DESY. Its first experimental results showed the system performance capabilities. Investigation of regulation limiting factors evidenced the need for control over fundamental cavity modes, which is done using complex controller structures and filter techniques. The improvement in measurement accuracy and detection bandwidth increased the regulation performance and contributed to integration of further control subsystems.

THPB096

High-power Sources of RF Radiation Driven by Periodic Laser Pulses

laser, electron, radiation, klystron

1044

S.V. Kuzikov, A.V. Savilov
IAP/RAS, Nizhny Novgorod, Russia
S.V. Kuzikov
Omega-P, Inc., New Haven, USA

Funding: Supported in part by DoE USA.
A fast, periodic modulation of electron RF sources can be carried out in a form of Q-factor switching by means of fast RF switches, or in a form of I-switching by means of the bunched electron beam. If modulation frequency equals to time which is necessary for RF radiation to travel along the cavity and to come back, the RF oscillator can produce periodic, giant, short pulses which are desirable for many applications in order to avoid a breakdown. The produced RF pulses are phase and frequency locked by modulation shape. The mentioned effects of the phase and frequency locking remain also possible for RF sources operated in a single-mode regime. In last case the modulation frequency should be close to natural single-mode oscillation frequency. For example, one might control operation of a BWO by means of a small periodical modulation of the electron voltage in a drift section in-between a cathode and the corrugated interaction section. The necessary voltage modulation can be provided by means of a DC generator those voltage due to a photoconductivity is externally modulated with definite frequency by laser which irradiates GaAs isolator inserted in-between the electrodes.