IPAC2011 - List of Keywords (cryomodule)

Paper	Title	Other Keywords	Page
MOOCA01	Production and Testing Experience with the SRF Cavities for the CEBAF 12 GeV Upgrade	cavity, HOM, SRF, higher-order-mode	26
	A. Burrill, G.K. Davis, F. Marhauser, C.E. Reece, A.V. Reilly, M. Stirbet JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The CEBAF recirculating CW electron linear accelerator at Jefferson Lab is presently undergoing a major upgrade to 12 GeV. This project includes the fabrication, preparation, and testing of 80 new 7-cell SRF cavities, followed by their incorporation into ten new cryomodules for subsequent testing and installation. In order to maximize the cavity Q over the full operable dynamic range in CEBAF (as high as 25 MV/m), the decision was taken to apply a streamlined preparation process that includes a final light temperature-controlled electropolish of the rf surface over the vendor-provided bulk BCP etch. Cavity processing work began at JLab in September 2010 and will continue through December 2011. The excellent performance results are exceeding project requirements and indicate a fabrication and preparation process that is stable and well controlled. The cavity production and performance experience to date will be summarized and lessons learned reported to the community.
	Slides MOOCA01 [4.376 MB]

MOODA01	Experience with the Cornell ERL Injector SRF Cryomodule during High Beam Current Operation	cavity, HOM, SRF, damping	35
	M. Liepe, D.L. Hartill, G.H. Hoffstaetter, S. Posen, P. Quigley, V. Veshcherevich CLASSE, Ithaca, New York, USA
	Funding: Supported by NSF award DMR-0807731 Cornell University has developed and fabricated a SCRF injector cryomodule for the acceleration of high current, low emittance CW beams. This cryomodule is based on superconducting RF technology with five 2-cell SRF cavities operated in CW mode. Strong Higher-Order-Mode (HOM) damping and high power RF input couplers support accelerating beam currents of tens of mA. The cryomodule is currently under extensive testing in the Cornell ERL injector prototype with CW beam currents exceeding 25 mA. This paper gives an overview of the experience gained during the high beam current operation of the cryomodule, with a focus on the intrinsic cavity quality factors, input coupler performance, and HOM damping.

MOODA02	S1-Global Module Tests at STF/KEK	cavity, SRF, feedback, linac	38
	D. Kostin, K. Jensch, L. Lilje, A. Matheisen, W.-D. Möller, P. Schilling, M. Schmökel, N.J. Walker, H. Weise DESY, Hamburg, Germany C. Adolphsen, C.D. Nantista SLAC, Menlo Park, California, USA M. Akemoto, S. Fukuda, K. Hara, H. Hayano, N. Higashi, E. Kako, H. Katagiri, Y. Kojima, Y. Kondo, T. Matsumoto, H. Matsushita, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, N. Ohuchi, T. Saeki, M. Satoh, 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 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, C. Pagani, R. Paparella, P. Pierini INFN/LASA, Segrate (MI), Italy
	S1-Global collaborative effort of INFN, DESY, FNAL, SLAC and KEK, recently successfully finished at KEK as a part of ILC GDE, is an important milestone for the ILC. International collaboration of three regions, Asia, North America and Europe, proved to be efficient on the construction and cold tests of the accelerating module consisting of 8 SRF cavities; 2 from FNAL, 2 from DESY and 4 from KEK. Three different cavity tuning systems were tested together with two types of high power couplers. The module was cooled down three times which enabled extensive high power tests with cavities, performance limits investigation, Lorentz force detuning tests, simultaneous multiple cavities operation and other activities such as an operation test of distributed RF scheme with low level RF feedback. The results of this S1-Global module test are presented and discussed.
	Slides MOODA02 [2.982 MB]

MOODB01	Dynamics of the IFMIF Very High-intensity Beam	rfq, emittance, space-charge, linac	53
	P.A.P. Nghiem, R.D. Duperrier, A. Mosnier, D. Uriot CEA/DSM/IRFU, France N. Chauvin, O. Delferrière, W. Simeoni CEA/IRFU, Gif-sur-Yvette, France M. Comunian INFN/LNL, Legnaro (PD), Italy C. Oliver CIEMAT, Madrid, Spain
	For the purpose of material studies for future nuclear fusion reactors, the IFMIF deuteron beams present a simultaneous combination of unprecedentedly high intensity (2x125 mA CW), power (2x5 MW) and space charge. Special considerations and new concepts have been developed in order to overcome these challenges. The global strategy for beam dynamics design in the 40 MeV IFMIF accelerators is presented, stressing on the control of micro-losses, and the possibility of on-line fine tuning. The obtained results are then analysed in terms of beam halo and emittance growth.
	Slides MOODB01 [3.807 MB]

MOPC079	Status of the Low Beta 0.07 Cryomodules for SPIRAL2	cavity, LLRF, vacuum, linac	256
	P. Bosland, P. Carbonnier, F. Eozénou, P. Galdemard, O. Piquet CEA/DSM/IRFU, France M. Anfreville, C. Madec, L. Maurice CEA/IRFU, Gif-sur-Yvette, France P.-E. Bernaudin, R. Ferdinand GANIL, Caen, France Y. Gomez-Martinez LPSC, Grenoble Cedex, France A. Pérolat CEA, Gif-sur-Yvette, France
	The status of the low beta cryomodules for SPIRAL2, supplied by the Irfu institute of CEA Saclay, is reported in this paper. We summarise in three parts the RF tests performed on the cavities in vertical cryostat, the RF power tests of the qualifying cryomodule performed in 2010 and the RF power tests performed in 2011 on the first cryomodule of the series

MOPC086	Description and First Experience with the RF Measurement Procedure for the European XFEL SC Cavity Production	cavity, HOM, SRF, superconducting-cavity	277
	A.A. Sulimov, Th. Buettner, A. Gössel, D. Kostin, G. Kreps, W.-D. Möller, D. Reschke, J.H. Thie, K. Twarowski DESY, Hamburg, Germany
	Cavity production for the European XFEL was recently started with first Nb sheets arriving. From this stage to the accelerating module being ready for the linac installation, many critical RF measurements are necessary. During the mechanical cavity fabrication the cavity half-cells, dumb-bells and end-groups are measured and sorted. The cavity spectrum and field profiles are measured and tuned. The HOM (Higher Oder Modes) couplers filter tuning, vertical cavity RF tests, cavity checks during the string assembly and final cavity performance measurements in the module as well as the fundamental mode and HOM RF spectra measurements complete the sequence. We present the procedures of the RF measurements and discuss the first results for the XFEL prototype modules with special attention for the cavity tuning.
	Poster MOPC086 [0.515 MB]

MOPC090	Tuner Performance in the S1-global Cryomodule	cavity, controls, high-voltage, coupling	286
	R. Paparella, A. Bosotti, C. Pagani INFN/LASA, Segrate (MI), Italy C. Albrecht, K. Jensch, L. Lilje DESY, Hamburg, Germany S. Barbanotti, Y.M. Pischalnikov, W. Schappert Fermilab, Batavia, USA H. Hayano, E. Kako, S. Noguchi, N. Ohuchi, Y. Yamamoto KEK, Ibaraki, Japan
	S1-Global is a collaborative effort of INFN, DESY, FNAL, SLAC and KEK, in the framework of the ILC global collaboration. For this project two cryomodules, 6 meter long and hosting four SC cavities each, were realized and successfully cold tested at KEK-STF. Three different cavity tuning systems, provided with fast tuning capability through piezoelectric actuators (piezo), were installed, and fully characterized in static and dynamic operation: Blade Tuner from INFN/FNAL, Saclay Tuner from DESY, Slide Jack Tuner from KEK. Finally, Lorenz Force Detuning (LFD) active compensation has been successfully achieved during high power cavity tests in pulsed RF regime, where active control of the LFD disturbance up to Hz-level residual detuning has been achieved with each type of tuning system up to the maximum gradient of each cavity. The installation procedures, together with the relevant results and their analyses are summarized in the paper.

MOPC091	Status of the XFEL 3.9 GHz Injector Section	cavity, cryogenics, linac, status	289
	P. Pierini, M. Bonezzi, A. Bosotti, M. Fusetti, P.M. Michelato, L. Monaco, R. Paparella, D. Sertore INFN/LASA, Segrate (MI), Italy E. Vogel DESY, Hamburg, Germany
	The European XFEL will use a superconducting third harmonic section to achieve the necessary beam quality for the FEL process. The concept has been successfully proven at the FLASH linac in DESY, with a 4 cavity superconducting module contributed by FNAL. The design of the third harmonic system at the XFEL injector is being finalized and prototypes of the components (cavities and couplers) have been fabricated and are currently in the testing stage. The paper will provide a status of the activities.

MOPC103	Cryostat for Testing HIE-ISOLDE Superconducting RF Cavities	cavity, vacuum, cryogenics, niobium	313
	O. Capatina, J.P. Brachet, G. Cuccuru, M. Pasini, T. Renaglia, M. Therasse, B. Vullierme CERN, Geneva, Switzerland
	The High Intensity and Energy ISOLDE (HIE-ISOLDE) project is a major upgrade of the existing ISOLDE and REX-ISOLDE facilities at CERN [1], with the objective of increasing the energy and the intensity of the delivered radioactive ion beams (RIB). This project aims to fill the request for a more energetic post accelerated beam by means of a new superconducting (SC) linac based on Quarter Wave Resonators (QWRs). A research and development program looking at all different aspects of the SC linac has started in 2008 and continued throughout 2010. In particular the R&D effort has focused on the development of the high β cavity (β = 10.3%), for which it has been decided to adopt the Nb sputtered on Cu substrate technology. Two prototype cavities were manufactured and are undergoing RF cold tests. The pre-series cavity fabrication is under way using 3D forged Cu billets. A single vacuum cryostat was designed and built to test these cavities at liquid helium temperatures. The paper details the main design concepts of the test cryostat as well as the results of the cryogenic behavior of the complete set-up including the cryostat, the RF cavity, the tuner and the main coupler.

MOPC105	Design of the High Beta Cryomodule for the HIE-ISOLDE Upgrade at CERN	vacuum, cavity, alignment, target	319
	L.R. Williams, A.P. Bouzoud, N. Delruelle, J. Gayde, Y. Leclercq, M. Pasini, J.Ph. G. L. Tock, G. Vandoni CERN, Geneva, Switzerland
	The major upgrade of the energy and intensity of the radioactive ion beams of the existing ISOLDE and REX-ISOLDE facilities at CERN will, in the long term, require downstream of the existing machine, the installation of four high-β and two low-β cryo-modules. The first stage of this upgrade, involving the design, construction, installation and commissioning of two high-β cryo-modules is approved and design work is underway at CERN. The high-β cryo-module houses five high-β superconducting cavities and one superconducting solenoid. As well as providing optimum conditions for physics, where the internal active components must remain aligned within tight tolerances, the cryo-modules need to function under stringent common vacuum and cryogenic conditions. To preserve the RF cavity performance their assembly and sub-system testing will need to be carried out using specifically designed tooling in a class 100 clean-room. We present the determining factors constraining the design of the high-β cryo-module together with the design choices that these factors have imposed.

MOPC112	Fabrication and Testing Status of CEBAF 12 GeV Upgrade Cavities	cavity, HOM, electron, status	337
	F. Marhauser, A. Burrill, G.K. Davis, D. Forehand, C. Grenoble, J. Hogan, R.B. Overton, A.V. Reilly, R.A. Rimmer, M. Stirbet JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The 12 GeV upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Laboratory (JLab) is under way. All cavities have been built by industry and are presently undergoing post-processing and final low and high power qualification before cryomodule assembly. The status is reported including fabrication-related experiences, observations and issues throughout production, post-processing and qualification.

MOPC113	Results of Cavity Series Fabrication at Jefferson Laboratory for the Cryomodule “R100”	cavity, HOM, target, damping	340
	F. Marhauser, W.A. Clemens, M.A. Drury, D. Forehand, J. Henry, S. Manning, R.B. Overton, R.S. Williams JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. A series production of eight superconducting RF cavities for the cryomodule R100 was conducted at JLab in 2010. The cavities underwent chemical post-processing prior to vertical high power testing and routinely exceeded the envisaged performance specifications. After cryomodule assembly, cavities were successfully high power acceptance tested. In this paper, we present the achievements paving the way for the first demonstration of 100 MV (and beyond) in a single cryomodule to be operated at CEBAF.

MOPC115	JLab SRF Cavity Fabrication Errors, Consequences and Lessons Learned	cavity, target, SRF, niobium	346
	F. Marhauser JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177 Today, elliptical superconducting RF (SRF) cavities are preferably made from deep-drawn niobium sheets as pursued at Jefferson Laboratory (JLab). The fabrication of a cavity incorporates various cavity cell machining, trimming and electron beam welding (EBW) steps as well as surface chemistry that add to forming errors creating geometrical deviations of the cavity shape from its design. An analysis of in-house built cavities over the last years revealed significant errors in cavity production. Past fabrication flaws are described and lessons learned applied successfully to the most recent in-house series production of multi-cell cavities.

MOPC126	High Power RF System for TRIUMF E-Linac Injector	cavity, klystron, TRIUMF, linac	373
	A.K. Mitra, Z.T. Ang, S. Calic, S.R. Koscielniak, R.E. Laxdal, R.W. Shanks, Q. Zheng TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	TRIUMF has been funded to build the first stage of an electron linac with a final energy of 50 MeV and 500 kW beam power. The e-linac consists of an injector section with electron gun with 650 MHz rf modulated grid, a room temperature 1.3 GHz buncher cavity, and injector cryomodule, and two main-linac cryomodules for the accelerating section to be installed sequentially. The injector module has one 9 cell cavity whereas each of the accelerating cryomodules contains two 9-cell SC cavities. The injector cryomodule will be fed by a 30 kW cw Inductive Output Tube (IOT)and the accelerating cryomodule will be powered by a cw klystron. A first goal is a beam test of the e-Linac injector to 10MeV in 2012. Installation and full rated output power tests of the IOT on a 50 ohms load have been carried out. The IOT is purchased from CPI, USA while the transmitter is sourced from Bruker BioSpin. A power coupler conditioning station utilizes the same IOT. The buncher cavity is driven from a Bruker 600W amplifier. In this paper, the conceptual design of the e-Linac rf system will be summarized and the high power rf system for the injector including IOT measurement results will be presented. SC stands for superconducting

MOPZ009	The Muon Linac for the International Design Study for the Neutrino Factory	linac, cavity, factory, lattice	838
	A. Kurup, M. Aslaninejad, C. Bonţoiu, J.K. Pozimski Imperial College of Science and Technology, Department of Physics, London, United Kingdom K.B. Beard Muons, Inc, Batavia, USA S.A. Bogacz, V.S. Morozov JLAB, Newport News, Virginia, USA
	The first stage of muon acceleration in the Neutrino Factory utilises a superconducting linac to accelerate muons from 244 MeV to 900 MeV. The linac is split into three types of cryomodules with decreasing magnetic fields and increasing amounts of RF voltage but with the design of the superconducting solenoid and RF cavities being the same for all cryomodules. The current status of the muon linac for the International Design Study for the Neutrino Factory will be presented including a final lattice design of the linac; electromagnetic simulations; and a preliminary cost estimate.

TUZB01	Superconducting RF Technology for Proton and Ion Accelerators	cavity, linac, SRF, proton	966
	G. Devanz CEA/DSM/IRFU, France
	The worldwide status of superconducting RF cavities and cryomodules for low velocity ion and proton particles is reviewed, with emphasis on the construction and tests of prototypes. A number of different multicell structures at a range of operating frequencies have been successfully realized. This review will cover the progress of several facilities under construction or being proposed: Spiral2, IFMIF-EVEDA, SPL, ESS, FRIB and ADS drivers.
	Slides TUZB01 [10.630 MB]

TUPC009	The Recent JINR Advances in Technology Development on Linear Accelerators	laser, electron, radiation, FEL	1006
	G. Shirkov, N. Balalykin, A. Dudarev, E. Syresin, G.V. Trubnikov, Yu.A. Yulian JINR, Dubna, Moscow Region, Russia E. Khazanov IAP/RAS, Nizhny Novgorod, Russia
	JINR experts take part in a few ILC related projects including photo injector prototype, participation in design and construction of cryomodules, RND on design of a new version of superconducting niobium resonator, laser metrology, etc. Some new results of this activity as well as recent data of ILC siting investigations in the Dubna region are presented.

TUPC097	Status of Cold Cavity Beam Position Monitor for STF	cavity, linac, vacuum, coupling	1236
	E.-S. Kim, A. Heo KNU, Deagu, Republic of Korea H. Hayano KEK, Ibaraki, Japan
	Cold cavity BPM was developed to meet high position resolution and bunch to bunch measurement time. It is designed based on re-entrant cavity and has Low-Q to achieve short signal decay time in L-band frequency with large aperture as 78mm. The beam test was performed to demonstrate position resolution at ATF main linac, which is operating with 1.6nC bunch charge, while BPM will be installed inside the ILC cyomodule with 3.2nC spacing 369ns like as ILC at STF. Stripline BPMs, ML2P and ML3P installed upstream and downstream of the BPM’s location respectively were used to predict its position. Reference cavity was optimized to use for synchronous detection. We had achieved ~340nm position resolution since position resolution was estimated due to limitation of system with noise, namely in case of ideal state. We will present configuration of beam test, procedure to measure position resolution and the result on the test. Furthermore, new design will be introduced to improve signal intensity and have heavy coupling.

WEPC087	Dark Current Simulations for the Cornell ERL	cavity, linac, electron, simulation	2214
	C.E. Mayes, C.S. Chiu, G.H. Hoffstaetter, V.O. Kostroun, D. Sagan CLASSE, Ithaca, New York, USA L.M. Nash North Carolina University, Chapel Hill, North Carolina, USA
	Funding: Supported by NSF award DMR-0807731 Charged particles unintentionally transported through an accelerator, collectively called the dark current, can be lost in the beam chamber and create a radiation hazard for both equipment and personnel. Here we simulate the creation of particles by field emission in the superconducting accelerating cavities of the Cornell Energy Recovery Linac, and track them to their loss points. These lost particles can then be used to simulate background radiation. The presented calculations are therefore an essential step in the design of appropriate radiation-shielding of components around the linac.

WEPC098	Automatic Pole and Q-Value Extraction for RF Structures	resonance, scattering, cavity, RF-structure	2241
	C. Potratz, H.-W. Glock, U. van Rienen Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany F. Marhauser JLAB, Newport News, Virginia, USA
	The experimental characterization of RF structures like accelerating cavities often demands for measuring resonant frequencies of Eigenmodes and corresponding (loaded) Q-values over a wide spectral range. A common procedure to determine the Q-values is the -3dB method, which works well for isolated poles, but may not be applicable directly in case of multiple poles residing in close proximity (e.g. for adjacent transverse modes differing by polarization). Although alternative methods may be used in such cases, this often comes at the expense of inherent systematic errors. We have developed an automation algorithm, which not only speeds up the measurement time significantly, but is also able to extract Eigenfrequencies and Q-values both for well isolated and overlapping poles. At the same time the measurement accuracy may be improved as a major benefit. To utilize this procedure merely complex scattering parameters have to be recorded for the spectral range of interest. In this paper we present the proposed algorithm applied to experimental data recorded for superconducting higher-order-mode damped multi-cell cavities as an application of high importance.

WEPO035	Thermal Performance of the S1-Global Cryomodule for ILC	cavity, radiation, linac, vacuum	2472
	N. Ohuchi, M. Akemoto, S. Fukuda, K. Hara, H. Hayano, N. Higashi, E. Kako, Y. Kojima, Y. Kondo, T. Matsumoto, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, T. Saeki, M. Satoh, 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 T.T. Arkan, S. Barbanotti, 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 Fermilab, Batavia, USA A. Bosotti, C. Pagani, R. Paparella, P. Pierini INFN/LASA, Segrate (MI), Italy D. Kostin, L. Lilje, A. Matheisen, W.-D. Möller, N.J. Walker, H. Weise DESY, Hamburg, Germany
	The S1-Global program is the international research collaboration among INFN, FNAL, DESY, SLAC and KEK as one of the GDE R&D for construction of ILC. The S1-Global cryomodule consists of two half-size cryomodules of 6 meter. One was designed by IFNF, and it contained two FNAL cavities and two DESY cavities. The associated components, like input couplers and RF cables, were same as the TTF-III cryomodule. The other was designed by KEK, and the thermal design was based on the TTF-III cryomodule. This cryomodule contains four KEK cavities with the associated components which were designed by KEK. For characterizing the thermal performances of two cryomodules, the static heat load and the temperature profiles of the cold components were measured. The temperature profiles of the components were compared between two cryomodules and the static heat load was evaluated with the design values of the cryomodules. The dynamic losses of the DESY, FNAL and two KEK cavities at their maximum operative gradients were measured and, with the measured losses, Q values were calculated. In this paper, we will make the summary of the thermal measurements of the S1-Global cryomodule.

WEPS059	Layout of the ESS Linac	linac, cavity, proton, rfq	2631
	H. Danared, M. Eshraqi, W. Hees, A. Jansson, M. Lindroos, S. Peggs, A. Ponton ESS, Lund, Sweden
	The European Spallation Source will use a 2.5 GeV, 50 mA pulsed proton linac to produce an average 5 MW of power on the spallation target. It will consist of normal-conducting part accelerating particles to 50 MeV in an RFQ and a drift-tube linac and a superconducting part with spoke resonators and two families of elliptical cavities. A high-energy beam transport takes the particles through an upgrade section and at least one bend and demagnifies the beam on to the target. The paper will present the current layout of the linac and discuss parameters that define its length from source to target.

WEPS060	Design and Optimization of ESS LINAC	linac, cavity, quadrupole, proton	2634
	M. Eshraqi ESS, Lund, Sweden
	The {\sc linac} of the European Spallation Source will accelerate the proton beam to its final energy mainly by using superconducting structures. Therefore choosing the right transition energy between these superconducting structures as well as choosing the cavity length and number of cells which enhances the acceleration is of great importance. Two types of {\sc linac}s will be studied, a {\sc linac} with superconducting quadrupoles and a {\sc linac} with normal conducting, resistive, quadrupoles. The procedure to find the optimized {\sc linac} will be described here.

WEPS062	Design and Beam Dynamics Study of Hybrid ESS LINAC	linac, cavity, accelerating-gradient, proton	2640
	M. Eshraqi, H. Danared, W. Hees, A. Jansson ESS, Lund, Sweden
	The European Spallation Source, {\sc ESS}, will use a superconducting linear accelerator delivering high current long pulses with an average beam power of 5~MW to the target station at 2.5~GeV. A new cryomodule architecture is proposed which allows for a transition between cryomodules in the sub-100~K region, this region can work even at room temperature. This new hybrid design will generate a lower heat load with respect to a fully segmented design - while still providing easy access to individual cryomodules for maintenance and repair. This paper will present a review of the {\sc linac} design, beam dynamics studies and a preliminary cryogenic analysis of the transition region.

WEPS090	The Myrrha Linear Accelerator	cavity, linac, rfq, proton	2718
	D. Vandeplassche SCK-CEN, Mol, Belgium J.-L. Biarrotte IPN, Orsay, France H. Klein, H. Podlech IAP, Frankfurt am Main, Germany
	Funding: European Atomic Energy Community's (EURATOM) Seventh Framework Programme FP7/2007-2011, grant agreement no. 269565 (MAX project) Accelerator Driven Systems (ADS) are promising tools for the efficient transmutation of nuclear waste products in dedicated industrial installations, called transmuters. The Myrrha project at Mol, Belgium, placed itself on the path towards these applications with a multipurpose and versatile system based on a liquid PbBi (LBE) cooled fast reactor (80 MWth) which may be operated in both critical and subcritical modes. In the latter case the core is fed by spallation neutrons obtained from a 600 MeV proton beam hitting the LBE coolant/target. The accelerator providing this beam is a high intensity CW superconducting linac which is laid out for the highest achievable reliability. The combination of a parallel redundant and of a fault tolerant scheme should allow obtaining an MTBF value in excess of 250 hours that is required for optimal integrity and successful operation of the ADS. Myrrha is expected to be operational in 2023. The forthcoming 4-year period is fully dedicated to R&D activities, and in the field of the accelerator they are strongly focused on the reliability aspects and on the proper shaping of the beam trip spectrum.

THPC178	Superconducting Planar Undulator Development in the UK	undulator, cryogenics, vacuum, radiation	3320
	J.A. Clarke, D.J. Scott, B.J.A. Shepherd STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom V. Bayliss, T.W. Bradshaw, A.J. Brummitt, G.W. Burton, M.J.D. Courthold, M.J. Hills, S.R. Watson, M.L. Woodward STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
	Superconducting undulators promise higher peak fields on axis than any other technology but they are still not a mainstream solution for 3rd or 4th generation light sources. A team within the UK is developing the design of a short period, narrow aperture, superconducting undulator that is planned to be installed and tested in the Diamond Light Source (DLS) in 2014. This paper will describe the main parameters of the undulator and the key design choices that have been made. Recent progress is then described in the areas of magnet modelling, mechanical design, cryogenic design, and prototyping. Finally, the next steps are described.

Paper

Title

Other Keywords

Page

MOOCA01

Production and Testing Experience with the SRF Cavities for the CEBAF 12 GeV Upgrade

cavity, HOM, SRF, higher-order-mode

26

A. Burrill, G.K. Davis, F. Marhauser, C.E. Reece, A.V. Reilly, M. Stirbet
JLAB, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
The CEBAF recirculating CW electron linear accelerator at Jefferson Lab is presently undergoing a major upgrade to 12 GeV. This project includes the fabrication, preparation, and testing of 80 new 7-cell SRF cavities, followed by their incorporation into ten new cryomodules for subsequent testing and installation. In order to maximize the cavity Q over the full operable dynamic range in CEBAF (as high as 25 MV/m), the decision was taken to apply a streamlined preparation process that includes a final light temperature-controlled electropolish of the rf surface over the vendor-provided bulk BCP etch. Cavity processing work began at JLab in September 2010 and will continue through December 2011. The excellent performance results are exceeding project requirements and indicate a fabrication and preparation process that is stable and well controlled. The cavity production and performance experience to date will be summarized and lessons learned reported to the community.

Slides MOOCA01 [4.376 MB]

MOODA01

Experience with the Cornell ERL Injector SRF Cryomodule during High Beam Current Operation

cavity, HOM, SRF, damping

35

M. Liepe, D.L. Hartill, G.H. Hoffstaetter, S. Posen, P. Quigley, V. Veshcherevich
CLASSE, Ithaca, New York, USA

Funding: Supported by NSF award DMR-0807731
Cornell University has developed and fabricated a SCRF injector cryomodule for the acceleration of high current, low emittance CW beams. This cryomodule is based on superconducting RF technology with five 2-cell SRF cavities operated in CW mode. Strong Higher-Order-Mode (HOM) damping and high power RF input couplers support accelerating beam currents of tens of mA. The cryomodule is currently under extensive testing in the Cornell ERL injector prototype with CW beam currents exceeding 25 mA. This paper gives an overview of the experience gained during the high beam current operation of the cryomodule, with a focus on the intrinsic cavity quality factors, input coupler performance, and HOM damping.

MOODA02

S1-Global Module Tests at STF/KEK

cavity, SRF, feedback, linac

38

D. Kostin, K. Jensch, L. Lilje, A. Matheisen, W.-D. Möller, P. Schilling, M. Schmökel, N.J. Walker, H. Weise
DESY, Hamburg, Germany
C. Adolphsen, C.D. Nantista
SLAC, Menlo Park, California, USA
M. Akemoto, S. Fukuda, K. Hara, H. Hayano, N. Higashi, E. Kako, H. Katagiri, Y. Kojima, Y. Kondo, T. Matsumoto, H. Matsushita, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, N. Ohuchi, T. Saeki, M. Satoh, 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
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, C. Pagani, R. Paparella, P. Pierini
INFN/LASA, Segrate (MI), Italy

S1-Global collaborative effort of INFN, DESY, FNAL, SLAC and KEK, recently successfully finished at KEK as a part of ILC GDE, is an important milestone for the ILC. International collaboration of three regions, Asia, North America and Europe, proved to be efficient on the construction and cold tests of the accelerating module consisting of 8 SRF cavities; 2 from FNAL, 2 from DESY and 4 from KEK. Three different cavity tuning systems were tested together with two types of high power couplers. The module was cooled down three times which enabled extensive high power tests with cavities, performance limits investigation, Lorentz force detuning tests, simultaneous multiple cavities operation and other activities such as an operation test of distributed RF scheme with low level RF feedback. The results of this S1-Global module test are presented and discussed.

Slides MOODA02 [2.982 MB]

MOODB01

Dynamics of the IFMIF Very High-intensity Beam

rfq, emittance, space-charge, linac

53

P.A.P. Nghiem, R.D. Duperrier, A. Mosnier, D. Uriot
CEA/DSM/IRFU, France
N. Chauvin, O. Delferrière, W. Simeoni
CEA/IRFU, Gif-sur-Yvette, France
M. Comunian
INFN/LNL, Legnaro (PD), Italy
C. Oliver
CIEMAT, Madrid, Spain

For the purpose of material studies for future nuclear fusion reactors, the IFMIF deuteron beams present a simultaneous combination of unprecedentedly high intensity (2x125 mA CW), power (2x5 MW) and space charge. Special considerations and new concepts have been developed in order to overcome these challenges. The global strategy for beam dynamics design in the 40 MeV IFMIF accelerators is presented, stressing on the control of micro-losses, and the possibility of on-line fine tuning. The obtained results are then analysed in terms of beam halo and emittance growth.

Slides MOODB01 [3.807 MB]

MOPC079

Status of the Low Beta 0.07 Cryomodules for SPIRAL2

cavity, LLRF, vacuum, linac

256

P. Bosland, P. Carbonnier, F. Eozénou, P. Galdemard, O. Piquet
CEA/DSM/IRFU, France
M. Anfreville, C. Madec, L. Maurice
CEA/IRFU, Gif-sur-Yvette, France
P.-E. Bernaudin, R. Ferdinand
GANIL, Caen, France
Y. Gomez-Martinez
LPSC, Grenoble Cedex, France
A. Pérolat
CEA, Gif-sur-Yvette, France

The status of the low beta cryomodules for SPIRAL2, supplied by the Irfu institute of CEA Saclay, is reported in this paper. We summarise in three parts the RF tests performed on the cavities in vertical cryostat, the RF power tests of the qualifying cryomodule performed in 2010 and the RF power tests performed in 2011 on the first cryomodule of the series

MOPC086

Description and First Experience with the RF Measurement Procedure for the European XFEL SC Cavity Production

cavity, HOM, SRF, superconducting-cavity

277

A.A. Sulimov, Th. Buettner, A. Gössel, D. Kostin, G. Kreps, W.-D. Möller, D. Reschke, J.H. Thie, K. Twarowski
DESY, Hamburg, Germany

Cavity production for the European XFEL was recently started with first Nb sheets arriving. From this stage to the accelerating module being ready for the linac installation, many critical RF measurements are necessary. During the mechanical cavity fabrication the cavity half-cells, dumb-bells and end-groups are measured and sorted. The cavity spectrum and field profiles are measured and tuned. The HOM (Higher Oder Modes) couplers filter tuning, vertical cavity RF tests, cavity checks during the string assembly and final cavity performance measurements in the module as well as the fundamental mode and HOM RF spectra measurements complete the sequence. We present the procedures of the RF measurements and discuss the first results for the XFEL prototype modules with special attention for the cavity tuning.

Poster MOPC086 [0.515 MB]

MOPC090

Tuner Performance in the S1-global Cryomodule

cavity, controls, high-voltage, coupling

286

R. Paparella, A. Bosotti, C. Pagani
INFN/LASA, Segrate (MI), Italy
C. Albrecht, K. Jensch, L. Lilje
DESY, Hamburg, Germany
S. Barbanotti, Y.M. Pischalnikov, W. Schappert
Fermilab, Batavia, USA
H. Hayano, E. Kako, S. Noguchi, N. Ohuchi, Y. Yamamoto
KEK, Ibaraki, Japan

S1-Global is a collaborative effort of INFN, DESY, FNAL, SLAC and KEK, in the framework of the ILC global collaboration. For this project two cryomodules, 6 meter long and hosting four SC cavities each, were realized and successfully cold tested at KEK-STF. Three different cavity tuning systems, provided with fast tuning capability through piezoelectric actuators (piezo), were installed, and fully characterized in static and dynamic operation: Blade Tuner from INFN/FNAL, Saclay Tuner from DESY, Slide Jack Tuner from KEK. Finally, Lorenz Force Detuning (LFD) active compensation has been successfully achieved during high power cavity tests in pulsed RF regime, where active control of the LFD disturbance up to Hz-level residual detuning has been achieved with each type of tuning system up to the maximum gradient of each cavity. The installation procedures, together with the relevant results and their analyses are summarized in the paper.

MOPC091

Status of the XFEL 3.9 GHz Injector Section

cavity, cryogenics, linac, status

289

P. Pierini, M. Bonezzi, A. Bosotti, M. Fusetti, P.M. Michelato, L. Monaco, R. Paparella, D. Sertore
INFN/LASA, Segrate (MI), Italy
E. Vogel
DESY, Hamburg, Germany

The European XFEL will use a superconducting third harmonic section to achieve the necessary beam quality for the FEL process. The concept has been successfully proven at the FLASH linac in DESY, with a 4 cavity superconducting module contributed by FNAL. The design of the third harmonic system at the XFEL injector is being finalized and prototypes of the components (cavities and couplers) have been fabricated and are currently in the testing stage. The paper will provide a status of the activities.

MOPC103

Cryostat for Testing HIE-ISOLDE Superconducting RF Cavities

cavity, vacuum, cryogenics, niobium

313

O. Capatina, J.P. Brachet, G. Cuccuru, M. Pasini, T. Renaglia, M. Therasse, B. Vullierme
CERN, Geneva, Switzerland

The High Intensity and Energy ISOLDE (HIE-ISOLDE) project is a major upgrade of the existing ISOLDE and REX-ISOLDE facilities at CERN [1], with the objective of increasing the energy and the intensity of the delivered radioactive ion beams (RIB). This project aims to fill the request for a more energetic post accelerated beam by means of a new superconducting (SC) linac based on Quarter Wave Resonators (QWRs). A research and development program looking at all different aspects of the SC linac has started in 2008 and continued throughout 2010. In particular the R&D effort has focused on the development of the high β cavity (β = 10.3%), for which it has been decided to adopt the Nb sputtered on Cu substrate technology. Two prototype cavities were manufactured and are undergoing RF cold tests. The pre-series cavity fabrication is under way using 3D forged Cu billets. A single vacuum cryostat was designed and built to test these cavities at liquid helium temperatures. The paper details the main design concepts of the test cryostat as well as the results of the cryogenic behavior of the complete set-up including the cryostat, the RF cavity, the tuner and the main coupler.

MOPC105

Design of the High Beta Cryomodule for the HIE-ISOLDE Upgrade at CERN

vacuum, cavity, alignment, target

319

L.R. Williams, A.P. Bouzoud, N. Delruelle, J. Gayde, Y. Leclercq, M. Pasini, J.Ph. G. L. Tock, G. Vandoni
CERN, Geneva, Switzerland

The major upgrade of the energy and intensity of the radioactive ion beams of the existing ISOLDE and REX-ISOLDE facilities at CERN will, in the long term, require downstream of the existing machine, the installation of four high-β and two low-β cryo-modules. The first stage of this upgrade, involving the design, construction, installation and commissioning of two high-β cryo-modules is approved and design work is underway at CERN. The high-β cryo-module houses five high-β superconducting cavities and one superconducting solenoid. As well as providing optimum conditions for physics, where the internal active components must remain aligned within tight tolerances, the cryo-modules need to function under stringent common vacuum and cryogenic conditions. To preserve the RF cavity performance their assembly and sub-system testing will need to be carried out using specifically designed tooling in a class 100 clean-room. We present the determining factors constraining the design of the high-β cryo-module together with the design choices that these factors have imposed.

MOPC112

Fabrication and Testing Status of CEBAF 12 GeV Upgrade Cavities

cavity, HOM, electron, status

337

F. Marhauser, A. Burrill, G.K. Davis, D. Forehand, C. Grenoble, J. Hogan, R.B. Overton, A.V. Reilly, R.A. Rimmer, M. Stirbet
JLAB, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
The 12 GeV upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Laboratory (JLab) is under way. All cavities have been built by industry and are presently undergoing post-processing and final low and high power qualification before cryomodule assembly. The status is reported including fabrication-related experiences, observations and issues throughout production, post-processing and qualification.

MOPC113

Results of Cavity Series Fabrication at Jefferson Laboratory for the Cryomodule “R100”

cavity, HOM, target, damping

340

F. Marhauser, W.A. Clemens, M.A. Drury, D. Forehand, J. Henry, S. Manning, R.B. Overton, R.S. Williams
JLAB, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
A series production of eight superconducting RF cavities for the cryomodule R100 was conducted at JLab in 2010. The cavities underwent chemical post-processing prior to vertical high power testing and routinely exceeded the envisaged performance specifications. After cryomodule assembly, cavities were successfully high power acceptance tested. In this paper, we present the achievements paving the way for the first demonstration of 100 MV (and beyond) in a single cryomodule to be operated at CEBAF.

MOPC115

JLab SRF Cavity Fabrication Errors, Consequences and Lessons Learned

cavity, target, SRF, niobium

346

F. Marhauser
JLAB, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177
Today, elliptical superconducting RF (SRF) cavities are preferably made from deep-drawn niobium sheets as pursued at Jefferson Laboratory (JLab). The fabrication of a cavity incorporates various cavity cell machining, trimming and electron beam welding (EBW) steps as well as surface chemistry that add to forming errors creating geometrical deviations of the cavity shape from its design. An analysis of in-house built cavities over the last years revealed significant errors in cavity production. Past fabrication flaws are described and lessons learned applied successfully to the most recent in-house series production of multi-cell cavities.

MOPC126

High Power RF System for TRIUMF E-Linac Injector

cavity, klystron, TRIUMF, linac

373

A.K. Mitra, Z.T. Ang, S. Calic, S.R. Koscielniak, R.E. Laxdal, R.W. Shanks, Q. Zheng
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

TRIUMF has been funded to build the first stage of an electron linac with a final energy of 50 MeV and 500 kW beam power. The e-linac consists of an injector section with electron gun with 650 MHz rf modulated grid, a room temperature 1.3 GHz buncher cavity, and injector cryomodule, and two main-linac cryomodules for the accelerating section to be installed sequentially. The injector module has one 9 cell cavity whereas each of the accelerating cryomodules contains two 9-cell SC cavities. The injector cryomodule will be fed by a 30 kW cw Inductive Output Tube (IOT)and the accelerating cryomodule will be powered by a cw klystron. A first goal is a beam test of the e-Linac injector to 10MeV in 2012. Installation and full rated output power tests of the IOT on a 50 ohms load have been carried out. The IOT is purchased from CPI, USA while the transmitter is sourced from Bruker BioSpin. A power coupler conditioning station utilizes the same IOT. The buncher cavity is driven from a Bruker 600W amplifier. In this paper, the conceptual design of the e-Linac rf system will be summarized and the high power rf system for the injector including IOT measurement results will be presented.
SC stands for superconducting

MOPZ009

The Muon Linac for the International Design Study for the Neutrino Factory

linac, cavity, factory, lattice

838

A. Kurup, M. Aslaninejad, C. Bonţoiu, J.K. Pozimski
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
K.B. Beard
Muons, Inc, Batavia, USA
S.A. Bogacz, V.S. Morozov
JLAB, Newport News, Virginia, USA

The first stage of muon acceleration in the Neutrino Factory utilises a superconducting linac to accelerate muons from 244 MeV to 900 MeV. The linac is split into three types of cryomodules with decreasing magnetic fields and increasing amounts of RF voltage but with the design of the superconducting solenoid and RF cavities being the same for all cryomodules. The current status of the muon linac for the International Design Study for the Neutrino Factory will be presented including a final lattice design of the linac; electromagnetic simulations; and a preliminary cost estimate.

TUZB01

Superconducting RF Technology for Proton and Ion Accelerators

cavity, linac, SRF, proton

966

G. Devanz
CEA/DSM/IRFU, France

The worldwide status of superconducting RF cavities and cryomodules for low velocity ion and proton particles is reviewed, with emphasis on the construction and tests of prototypes. A number of different multicell structures at a range of operating frequencies have been successfully realized. This review will cover the progress of several facilities under construction or being proposed: Spiral2, IFMIF-EVEDA, SPL, ESS, FRIB and ADS drivers.

Slides TUZB01 [10.630 MB]

TUPC009

The Recent JINR Advances in Technology Development on Linear Accelerators

laser, electron, radiation, FEL

1006

G. Shirkov, N. Balalykin, A. Dudarev, E. Syresin, G.V. Trubnikov, Yu.A. Yulian
JINR, Dubna, Moscow Region, Russia
E. Khazanov
IAP/RAS, Nizhny Novgorod, Russia

JINR experts take part in a few ILC related projects including photo injector prototype, participation in design and construction of cryomodules, RND on design of a new version of superconducting niobium resonator, laser metrology, etc. Some new results of this activity as well as recent data of ILC siting investigations in the Dubna region are presented.

TUPC097

Status of Cold Cavity Beam Position Monitor for STF

cavity, linac, vacuum, coupling

1236

E.-S. Kim, A. Heo
KNU, Deagu, Republic of Korea
H. Hayano
KEK, Ibaraki, Japan

Cold cavity BPM was developed to meet high position resolution and bunch to bunch measurement time. It is designed based on re-entrant cavity and has Low-Q to achieve short signal decay time in L-band frequency with large aperture as 78mm. The beam test was performed to demonstrate position resolution at ATF main linac, which is operating with 1.6nC bunch charge, while BPM will be installed inside the ILC cyomodule with 3.2nC spacing 369ns like as ILC at STF. Stripline BPMs, ML2P and ML3P installed upstream and downstream of the BPM’s location respectively were used to predict its position. Reference cavity was optimized to use for synchronous detection. We had achieved ~340nm position resolution since position resolution was estimated due to limitation of system with noise, namely in case of ideal state. We will present configuration of beam test, procedure to measure position resolution and the result on the test. Furthermore, new design will be introduced to improve signal intensity and have heavy coupling.

WEPC087

Dark Current Simulations for the Cornell ERL

cavity, linac, electron, simulation

2214

C.E. Mayes, C.S. Chiu, G.H. Hoffstaetter, V.O. Kostroun, D. Sagan
CLASSE, Ithaca, New York, USA
L.M. Nash
North Carolina University, Chapel Hill, North Carolina, USA

Funding: Supported by NSF award DMR-0807731
Charged particles unintentionally transported through an accelerator, collectively called the dark current, can be lost in the beam chamber and create a radiation hazard for both equipment and personnel. Here we simulate the creation of particles by field emission in the superconducting accelerating cavities of the Cornell Energy Recovery Linac, and track them to their loss points. These lost particles can then be used to simulate background radiation. The presented calculations are therefore an essential step in the design of appropriate radiation-shielding of components around the linac.

WEPC098

Automatic Pole and Q-Value Extraction for RF Structures

resonance, scattering, cavity, RF-structure

2241

C. Potratz, H.-W. Glock, U. van Rienen
Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
F. Marhauser
JLAB, Newport News, Virginia, USA

The experimental characterization of RF structures like accelerating cavities often demands for measuring resonant frequencies of Eigenmodes and corresponding (loaded) Q-values over a wide spectral range. A common procedure to determine the Q-values is the -3dB method, which works well for isolated poles, but may not be applicable directly in case of multiple poles residing in close proximity (e.g. for adjacent transverse modes differing by polarization). Although alternative methods may be used in such cases, this often comes at the expense of inherent systematic errors. We have developed an automation algorithm, which not only speeds up the measurement time significantly, but is also able to extract Eigenfrequencies and Q-values both for well isolated and overlapping poles. At the same time the measurement accuracy may be improved as a major benefit. To utilize this procedure merely complex scattering parameters have to be recorded for the spectral range of interest. In this paper we present the proposed algorithm applied to experimental data recorded for superconducting higher-order-mode damped multi-cell cavities as an application of high importance.

WEPO035

Thermal Performance of the S1-Global Cryomodule for ILC

cavity, radiation, linac, vacuum

2472

N. Ohuchi, M. Akemoto, S. Fukuda, K. Hara, H. Hayano, N. Higashi, E. Kako, Y. Kojima, Y. Kondo, T. Matsumoto, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, T. Saeki, M. Satoh, 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
T.T. Arkan, S. Barbanotti, 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
Fermilab, Batavia, USA
A. Bosotti, C. Pagani, R. Paparella, P. Pierini
INFN/LASA, Segrate (MI), Italy
D. Kostin, L. Lilje, A. Matheisen, W.-D. Möller, N.J. Walker, H. Weise
DESY, Hamburg, Germany

The S1-Global program is the international research collaboration among INFN, FNAL, DESY, SLAC and KEK as one of the GDE R&D for construction of ILC. The S1-Global cryomodule consists of two half-size cryomodules of 6 meter. One was designed by IFNF, and it contained two FNAL cavities and two DESY cavities. The associated components, like input couplers and RF cables, were same as the TTF-III cryomodule. The other was designed by KEK, and the thermal design was based on the TTF-III cryomodule. This cryomodule contains four KEK cavities with the associated components which were designed by KEK. For characterizing the thermal performances of two cryomodules, the static heat load and the temperature profiles of the cold components were measured. The temperature profiles of the components were compared between two cryomodules and the static heat load was evaluated with the design values of the cryomodules. The dynamic losses of the DESY, FNAL and two KEK cavities at their maximum operative gradients were measured and, with the measured losses, Q values were calculated. In this paper, we will make the summary of the thermal measurements of the S1-Global cryomodule.

WEPS059

Layout of the ESS Linac

linac, cavity, proton, rfq

2631

H. Danared, M. Eshraqi, W. Hees, A. Jansson, M. Lindroos, S. Peggs, A. Ponton
ESS, Lund, Sweden

The European Spallation Source will use a 2.5 GeV, 50 mA pulsed proton linac to produce an average 5 MW of power on the spallation target. It will consist of normal-conducting part accelerating particles to 50 MeV in an RFQ and a drift-tube linac and a superconducting part with spoke resonators and two families of elliptical cavities. A high-energy beam transport takes the particles through an upgrade section and at least one bend and demagnifies the beam on to the target. The paper will present the current layout of the linac and discuss parameters that define its length from source to target.

WEPS060

Design and Optimization of ESS LINAC

linac, cavity, quadrupole, proton

2634

M. Eshraqi
ESS, Lund, Sweden

The {\sc linac} of the European Spallation Source will accelerate the proton beam to its final energy mainly by using superconducting structures. Therefore choosing the right transition energy between these superconducting structures as well as choosing the cavity length and number of cells which enhances the acceleration is of great importance. Two types of {\sc linac}s will be studied, a {\sc linac} with superconducting quadrupoles and a {\sc linac} with normal conducting, resistive, quadrupoles. The procedure to find the optimized {\sc linac} will be described here.

WEPS062

Design and Beam Dynamics Study of Hybrid ESS LINAC

linac, cavity, accelerating-gradient, proton

2640

M. Eshraqi, H. Danared, W. Hees, A. Jansson
ESS, Lund, Sweden

The European Spallation Source, {\sc ESS}, will use a superconducting linear accelerator delivering high current long pulses with an average beam power of 5~MW to the target station at 2.5~GeV. A new cryomodule architecture is proposed which allows for a transition between cryomodules in the sub-100~K region, this region can work even at room temperature. This new hybrid design will generate a lower heat load with respect to a fully segmented design - while still providing easy access to individual cryomodules for maintenance and repair. This paper will present a review of the {\sc linac} design, beam dynamics studies and a preliminary cryogenic analysis of the transition region.

WEPS090

The Myrrha Linear Accelerator

cavity, linac, rfq, proton

2718

D. Vandeplassche
SCK-CEN, Mol, Belgium
J.-L. Biarrotte
IPN, Orsay, France
H. Klein, H. Podlech
IAP, Frankfurt am Main, Germany

Funding: European Atomic Energy Community's (EURATOM) Seventh Framework Programme FP7/2007-2011, grant agreement no. 269565 (MAX project)
Accelerator Driven Systems (ADS) are promising tools for the efficient transmutation of nuclear waste products in dedicated industrial installations, called transmuters. The Myrrha project at Mol, Belgium, placed itself on the path towards these applications with a multipurpose and versatile system based on a liquid PbBi (LBE) cooled fast reactor (80 MWth) which may be operated in both critical and subcritical modes. In the latter case the core is fed by spallation neutrons obtained from a 600 MeV proton beam hitting the LBE coolant/target. The accelerator providing this beam is a high intensity CW superconducting linac which is laid out for the highest achievable reliability. The combination of a parallel redundant and of a fault tolerant scheme should allow obtaining an MTBF value in excess of 250 hours that is required for optimal integrity and successful operation of the ADS. Myrrha is expected to be operational in 2023. The forthcoming 4-year period is fully dedicated to R&D activities, and in the field of the accelerator they are strongly focused on the reliability aspects and on the proper shaping of the beam trip spectrum.

THPC178

Superconducting Planar Undulator Development in the UK

undulator, cryogenics, vacuum, radiation

3320

J.A. Clarke, D.J. Scott, B.J.A. Shepherd
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
V. Bayliss, T.W. Bradshaw, A.J. Brummitt, G.W. Burton, M.J.D. Courthold, M.J. Hills, S.R. Watson, M.L. Woodward
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom

Superconducting undulators promise higher peak fields on axis than any other technology but they are still not a mainstream solution for 3rd or 4th generation light sources. A team within the UK is developing the design of a short period, narrow aperture, superconducting undulator that is planned to be installed and tested in the Diamond Light Source (DLS) in 2014. This paper will describe the main parameters of the undulator and the key design choices that have been made. Recent progress is then described in the areas of magnet modelling, mechanical design, cryogenic design, and prototyping. Finally, the next steps are described.