Keyword: cryomodule
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MO1A01 The FRIB Superconducting Linac - Status and Plans ion, linac, cryogenics, SRF 1
 
  • J. Wei, H. Ao, S. Beher, N.K. Bultman, F. Casagrande, C. Compton, L.R. Dalesio, K.D. Davidson, A. Facco, F. Feyzi, V. Ganni, A. Ganshyn, P.E. Gibson, T. Glasmacher, W. Hartung, L. Hodges, L.T. Hoff, H.-C. Hseuh, A. Hussain, M. Ikegami, S. Jones, K. Kranz, R.E. Laxdal, S.M. Lidia, G. Machicoane, F. Marti, S.J. Miller, D.G. Morris, A.C. Morton, J.A. Nolen, P.N. Ostroumov, J.T. Popielarski, L. Popielarski, G. Pozdeyev, T. Russo, K. Saito, G. Shen, S. Stanley, H. Tatsumoto, T. Xu, Y. Yamazaki
    FRIB, East Lansing, USA
  • K. Dixon, M. Wiseman
    JLab, Newport News, Virginia, USA
  • A. Facco
    INFN/LNL, Legnaro (PD), Italy
  • K. Hosoyama
    KEK, Ibaraki, Japan
  • H.-C. Hseuh
    BNL, Upton, Long Island, New York, USA
  • M.P. Kelly, J.A. Nolen
    ANL, Argonne, Illinois, USA
  • R.E. Laxdal
    TRIUMF, Vancouver, Canada
 
  With an average beam power two orders of magnitude higher than operating heavy-ion facilities, the Facility for Rare Isotope Beams (FRIB) stands at the power frontier of the accelerator family. This report summarizes the current design and construction status as well as plans for commissioning, operations and upgrades.
Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 and the National Science Foundation under Cooperative Agreement PHY-1102511.
 
slides icon Slides MO1A01 [48.813 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MO1A01  
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MOOP01 The SARAF-LINAC Project Status linac, status, rfq, solenoid 38
 
  • N. Pichoff, B. Gastineau, P. Girardot
    CEA/DSM/IRFU, France
  • N. Bazin, D. Chirpaz-Cerbat, B. Dalena, G. Ferrand, P. Gastinel, F. Gougnaud, M. Jacquemet, C. Madec, P.A.P. Nghiem, D. Uriot
    CEA/IRFU, Gif-sur-Yvette, France
  • P. Bertrand, M. Di Giacomo, R. Ferdinand, J.-M. Lagniel
    GANIL, Caen, France
 
  SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). CEA is in charge of the design, construction and commissioning of the superconducting linac (SARAF-LINAC Project). This paper presents to the accelerator community the status at August 2016 of the SARAF-LINAC Project.  
slides icon Slides MOOP01 [4.978 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOOP01  
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MOOP02 Current Status of Superconducting Linac for the Rare Isotope Science Project linac, cavity, ion, rfq 41
 
  • H.J. Kim, I.S. Hong, H.C. Jung, W.K. Kim, Y.H. Kim, Y. Kim, B.-S. Park, I. Shin
    IBS, Daejeon, Republic of Korea
 
  The RISP (Rare Isotope Science Project) has been proposed as a multi-purpose accelerator facility for providing beams of exotic rare isotopes of various energies. It can deliver ions from proton to uranium. Proton and uranium ions are accelerated upto 600 MeV and 200 MeV/u respectively. The facility consists of three superconducting linacs of which superconducting cavities are independently phased. Requirement of the linac design is especially high for acceleration of multiple charge beams. We present the RISP linac design, the prototyping of superconducting cavity and cryomodule.  
slides icon Slides MOOP02 [5.566 MB]  
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MOOP11 Operation of the CEBAF 100 MV Cryomodules cavity, operation, electron, controls 65
 
  • C. Hovater, T.L. Allison, R. Bachimanchi, G.H. Biallas, E. Daly, M.A. Drury, A. Freyberger, R.L. Geng, G.E. Lahti, R.A. Legg, C.I. Mounts, R.M. Nelson, T. E. Plawski, T. Powers
    JLab, Newport News, Virginia, USA
 
  Funding: Authored by JSA, LLC under U.S. DOE Contract DE-AC05- 06OR23177.
The Continuous Electron Beam Accelerator Facility (CEBAF) 12 GeV upgrade reached its design energy in December of 2015. Since then CEBAF has been delivering 12 GeV beam to experimental Hall D and 11 GeV to experimental halls A and B in support of Nuclear physics. To meet this energy goal, ten new 100 MV cryomodules (80 cavities) and RF systems were installed in 2013. The superconducting RF cavities are designed to operate CW at a average accelerating gradient of 19.2 MV/m. To support the higher gradients and higher QL (3.2×107) operations, the RF system uses 13 kW klystrons and digital LLRF to power and control each cavity. This paper reports on the C100 operation and optimization improvements of the RF system and cryomodules.
 
slides icon Slides MOOP11 [1.574 MB]  
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MOPRC025 Final Design of the Fully Equipped HWR Cavities for SARAF cavity, linac, multipactoring, simulation 123
 
  • G. Ferrand
    CEA/DSM/IRFU, France
  • L. Boudjaoui, P. Hardy, F. Leseigneur, C. Madec, N. Misiara, N. Pichoff
    CEA/IRFU, Gif-sur-Yvette, France
 
  SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). CEA is in charge of the design, construction and commissioning of the superconducting linac (SARAF-LINAC Project). The SCL is made up of 4 cryomodules: the first two will host each 6 half-wave resonator (HWR) low beta cavities (β = 0.09) at 176 MHz; the last two will host each 7 HWR high-beta cavities (β = 0.18) at 176 MHz. The fully equipped cavity includes the niobium cavity with a helium tank, an input power couplers and a frequency tuning system. The final RF design of the low and high beta cavities will be presented in this poster, as well as the RF design of the couplers, the expected tuning range of the cavities and the multipactor analysis.  
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MOPRC026 Mechanical Design of the HWR Cavities for the SARAF SRF LINAC cavity, linac, simulation, SRF 126
 
  • N. Misiara, L. Boudjaoui, G. Ferrand, P. Hardy, F. Leseigneur, C. Madec, N. Pichoff
    CEA/IRFU, Gif-sur-Yvette, France
 
  SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). CEA is in charge of the design, construction and commissioning of the superconducting linac (SARAF-LINAC Project). The SCL consists in 4 cryomodules. The first two identical cryomodules host 6 half-wave resonator (HWR) low beta cavities (β = 0.09) at 176 MHz. The last two identical cryomodules will host 7 HWR high-beta cavities (β = 0.18) at 176 MHz. The fully equipped cavity includes the niobium cavity with its helium tank, the couplers and the frequency tuning system. In this paper, the mechanical design and the foreseen qualification procedures for both cavities and tuning systems are presented with compliance, to the best extent, to the rules of Unfired Pressure Vessels NF-EN 13445 (1-5) standards.  
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MOPLR008 Status Of the ILC Main Linac Design linac, lattice, emittance, quadrupole 149
 
  • A. Saini, V.V. Kapin, N. Solyak
    Fermilab, Batavia, Illinois, USA
 
  International Linear collider (ILC) is a proposed accelerator facility which is primarily based on two 11-km long superconducting main linacs. In this paper we present recent updates on the main linac design and discuss changes made in order to meet specification outlined in the technical design report (TDR).  
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MOPLR010 4 K SRF Operation of the 10 MeV CEBAF Photo-Injector operation, SRF, cavity, cryogenics 155
 
  • G.V. Eremeev, M.A. Drury, J.M. Grames, R. Kazimi, M. Poelker, J.P. Preble, R. Suleiman, Y.W. Wang, M. Wright
    JLab, Newport News, Virginia, USA
 
  Funding: Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
SRF accelerating cavities are often operated in superfluid helium of temperature near 2 K to enhance the cavity quality factor Q0 and manage cryogenic heat loads, which are particularly important at large SRF accelerator facilities. This temperature paradigm, however, need not put SRF technology out of the reach of small institutions or even limit SRF operation at large facilities to provide 10-100 MeV beam energy. At the Jefferson Lab CEBAF accelerator there are regularly scheduled maintenance periods during which the liquid helium temperature is raised to 4 K, reducing cryogenic plant power consumption by ~50% and saving megawatts of electrical power. During such a recent period, we accelerated a continuous-wave electron beam at the CEBAF photo-injector to 6.3 MeV/c with current ~80μA using two niobium cavities at helium temperature of 4 K. This contribution describes the SRF and cryogenic performance and uses measured beam quality and energy stability as key metrics. These measurements indicate that 4 K operation of niobium SRF cavities in CEBAF and at small institutions may be a sensible and cost effective mode of operation, provided the cryogenic load associated with lower Q0 is manageable for the number of SRF cavities needed. For Jefferson Lab, this enhances our scientific reach allowing additional low-energy ~10 MeV experiments each year.
 
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MOPLR015 Thermal-Mechanical Study of 3.9 GHz CW Coupler and Cavity for LCLS-II Project cavity, simulation, resonance, linac 171
 
  • I.V. Gonin, E.R. Harms, T.N. Khabiboulline, N. Solyak, V.P. Yakovlev
    Fermilab, Batavia, Illinois, USA
 
  Third harmonic system was originally developed by Fermilab for FLASH facility at DESY and then was adopted and modified by INFN for the XFEL project [1-3]. In contrast to XFEL project, all cryomodules in LCLS-II project will operate in CW regime with higher RF average power for 1.3 GHz and 3.9 GHz cavities and couplers. Design of the cavity and fundamental power coupler has been modified to satisfy LCLS-II requirements. In this paper we discuss the results of COMSOL thermal and mechanical analysis of the 3.9 GHz coupler and cavity to verify proposed modifica-tion of the design. For the dressed cavity we present simulations of Lorentz force detuning, helium pressure sensitivity df/dP and major mechanical resonances.  
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MOPLR020 Challenges in Realizing the LCLS-II Cryomodule Production cavity, SRF, linac, superconducting-RF 181
 
  • A. Burrill
    SLAC, Menlo Park, California, USA
 
  The LCLS-II project requires the assembly and installation of 37 cryomodules in order to deliver a 4 GeV electron beam to the undulators to produce both soft and hard x-rays at a repetition rate up to 1 MHz. All of the cryomodules will operate in continuous wave mode, with 35 operating at 1.3 GHz for acceleration and 2 operating at 3.9 GHz to linearize the longitudinal beam profile. One of the challenges of this project, and the topic of this paper, is coordinating the effort of three DOE labs in order to realize this machine in just a few years time. This coordination is necessary due to the fact that the cryomodules will be assembled at both Jefferson Lab and Fermi Lab, tested, and then shipped to SLAC for installation, commissioning and operation. This paper will report on our experiences to date, issues that have been identified and planned mitigation going forward.  
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MOPLR022 Commissioning and First Results from the Fermilab Cryomodule Test Stand cavity, vacuum, controls, radiation 185
 
  • E.R. Harms, M.H. Awida, C.M. Baffes, K. Carlson, S.K. Chandrasekaran, B.E. Chase, E. Cullerton, J.P. Edelen, J. Einstein, C.M. Ginsburg, A. Grassellino, B.J. Hansen, J.P. Holzbauer, S. Kazakov, T.N. Khabiboulline, M.J. Kucera, J.R. Leibfritz, A. Lunin, D. McDowell, M.W. McGee, D.J. Nicklaus, D.F. Orris, J.P. Ozelis, J.F. Patrick, T.B. Petersen, Y.M. Pischalnikov, P.S. Prieto, O.V. Prokofiev, J. Reid, W. Schappert, D.A. Sergatskov, N. Solyak, R.P. Stanek, D. Sun, M.J. White, C. Worel, G. Wu
    Fermilab, Batavia, Illinois, USA
 
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. De-AC02-07CH11359 with the United States Department of Energy.
A new test stand dedicated to SRF cryomodule testing, CMTS1, has been commissioned and is now in operation at Fermilab. The first device to be cooled down and powered in this facility is the prototype 1.3 GHz cryomodule assembled at Fermilab for LCLS-II. We describe the demonstrated capabilities of CMTS1, report on steps taken during commissioning, provide an overview of first test results, and survey future plans.
 
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MOPLR024 Progress Towards Nb3Sn CEBAF Injector Cryomodule cavity, niobium, operation, electron 193
 
  • G.V. Eremeev, K. Macha, U. Pudasaini, C.E. Reece, A-M. Valente-Feliciano
    JLab, Newport News, Virginia, USA
 
  Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Operations at 4 K instead of 2 K have the potential to reduce the operational cost of an SRF linac by a factor of 3, if the cavity quality factor can be maintained. Cavities coated with Nb3Sn have been shown to achieve the accelerating gradients above 10 MV/m with a quality factor around 1010 at 4 K. Because such performance is already pertinent for CEBAF injector cryomodule, we are working to extend these results to CEBAF accelerator cavities envisioning coating of two CEBAF 5-cell cavities with Nb3Sn. They will be installed in an injector cryomodule and tested with beam. The progress on this path is reported in this contribution.
 
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MOPLR026 Material Qualification of LCLS-II Production Niobium Material Including RF and Flux Expulsion Measurements on Single Cell Cavities cavity, niobium, SRF, controls 199
 
  • A.D. Palczewski, F. Marhauser
    JLab, Newport News, Virginia, USA
  • A. Grassellino, S. Posen
    Fermilab, Batavia, Illinois, USA
 
  Funding: Work at JLab is supported by the U.S. Department of Energy under contract DE-AC05-06OR23177 and Fermilab is operated by Fermi Research Alliance, LLC under Contract No. De-AC02-07CH11359.
It has been shown that cooldown details through transition temperature can significantly affect the amount of trapped magnetic flux in SRF cavities, which can lead to performance degradation proportional to the magnitude of the ambient magnetic field.[*] It has also more recently been shown that depending on the exact material properties - even when the material used originated from the same batch from the same vendor - and subsequent heat treatment, the percent of flux trapped during a cool-down could vary widely for identical cool-down parameters.[**] For LCLS-II, two material vendors have produced half of the niobium used for the cavity cells (Tokyo Denkai Co., Ltd. (TD) and Ningxia Orient Tantalum Industry Co., Ltd. (NX)). Both vendors delivered material well within specifications set out by the project (according to ASTM B 393-05), which allows yet some variation of material characteristics such as grain size and defect density. In this contribution, we present RF and magnetic flux expulsion measurements of four single cell cavities made out of two different niobium batches from each of the two LCLS-II material suppliers and draw conclusions on potential correlations of flux expulsion capability with material parameters. We present observations of limited flux expulsion in cavities made from the production material and treated with the baseline LCLS-II recipe.
[*] A. Romanenko et al J. Appl. Phys. 115, 184903 (2014)
[**] S. Posenet et al., Journal of Applied Physics 119, 213903 (2016).
 
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TU1A05 High Power Operation of SNS SC Linac cavity, linac, ion, operation 348
 
  • M.A. Plum
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: Work performed at (or work supported by) Oak Ridge National Laboratory, which is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.
The SNS superconducting linac (SCL) provides 972 MeV, 1.5 MW H− beam for the storage ring and neutron spallation target. It has now been in operation for 11 years, and we have gained some experience in long-term operational issues. Three inter-related issues are gradient changes, errant beams, and trip rates. In this presentation we will provide an update on our progress to mitigate these issues, and also report on the overall status of the SCL.
 
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TUOP02 CBETA: The Cornell/BNL 4-Turn ERL with FFAG Return Arcs for eRHIC Prototyping linac, electron, gun, SRF 384
 
  • G.H. Hoffstaetter, J. Barley, A.C. Bartnik, I.V. Bazarov, J. Dobbins, B.M. Dunham, R.G. Eichhorn, R.E. Gallagher, C.M. Gulliford, Y. Li, M. Liepe, W. Lou, C.E. Mayes, J.R. Patterson, D.M. Sabol, E.N. Smith, K.W. Smolenski
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • I. Ben-Zvi, J.S. Berg, S.J. Brooks, G.J. Mahler, F. Méot, M.G. Minty, S. Peggs, V. Ptitsyn, T. Roser, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, H. Witte
    BNL, Upton, Long Island, New York, USA
  • D. Douglas
    JLab, Newport News, Virginia, USA
 
  Cornell University has prototyped technology essential for any high brightness electron ERL. This includes a DC gun and an SRF injector Linac with world-record current and normalized brightness in a bunch train, a high-current CW cryomodule, a high-power beam stop, and several diagnostics tools for high-current and high-brightness beams, e.g. slid measurements for 6-D phase-space densities, a fast wire scanner for beam profiles, and beam loos diagnostics. All these are now available to equip a one-cryomodule ERL, and laboratory space has been cleared out and is radiation shielded to install this ERL at Cornell. BNL has designed a multi-turn ERL for eRHIC, where beam is transported more than 20 times around the RHIC tunnel. The number of transport lines is minimized by using two non-scaling (NS) FFAG arcs. A collaboration between BNL and Cornell has been formed to investigate the new NS-FFAG optics and the multi-turn eRHIC ERL design by building a 4-turn, one-cryomodule ERL at Cornell. It has a NS-FFAG return loop built with permanent magnets and is meant to accelerate 40mA beam to 200MeV.  
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TUPLR007 LCLS-II Cryomodules Production at Fermilab cavity, SRF, vacuum, alignment 481
 
  • T.T. Arkan, C.J. Grimm, J.A. Kaluzny, Y.O. Orlov, T.J. Peterson, K. Premo
    Fermilab, Batavia, Illinois, USA
 
  Funding: US DOE
LCLS-II is an upgrade project for the linear coherent light source (LCLS) at SLAC. The LCLS-II linac will consist of thirty-five 1.3 GHz and two 3.9 GHz superconducting RF continuous wave (CW) cryomodules that Fermilab and Jefferson Lab (JLab) will assemble in collaboration with SLAC. The LCLS-II 1.3 GHz cryomodule design is based on the European XFEL pulsed-mode cryomodule design with modifications needed for CW operation. Fermilab and JLab will each assemble and test a prototype 1.3 GHz cryomodule to assess the results of the CW modifications, in advance of 16 and 17 production 1.3 GHz cryomodules, respectively. Fermilab is solely responsible for the 3.9 GHz cryomodules. After the prototype cryomodule tests are complete and lessons learned incorporated, both laboratories will increase their cryomodule production rates to meet the challenging LCLS-II project requirement of approximately one cryomodule per month per laboratory. This paper presents the Fermilab Cryomodule Assembly Facility (CAF) infrastructure for LCLS-II cryomodule production, the Fermilab prototype 1.3 GHz CW cryomodule (pCM) assembly and readiness for production assembly.
 
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TUPLR010 Measurements and Analysis of Cavity Microphonics and Frequency Control in the Cornell ERL Main Linac Prototype Cryomodule cavity, linac, vacuum, LLRF 488
 
  • M. Ge, N. Banerjee, J. Dobbins, R.G. Eichhorn, F. Furuta, G.H. Hoffstaetter, M. Liepe, P. Quigley, J. Sears, V. Veshcherevich
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  The Cornell Main Linac cryomodule (MLC) is a key component in the CBETA project. The SRF cavities with high loaded-Q in the MLC are very sensitive to microphonics from mechanical vibrations. Poor frequency stability of the cavities would dramatically increase the input RF power required to maintain stable accelerating fields in the SRF cavities. In this paper, we present detailed results from microphonics measurement for the cavities in the MLC, discuss dominant vibration sources, and show vibration damping results. The current microphonics level meets the CBETA requirement of a 36MeV energy gain without applying fast tuner compensation.  
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TUPLR011 Performance of the Novel Cornell ERL Main Linac Prototype Cryomodule cavity, linac, SRF, HOM 492
 
  • F. Furuta, J. Dobbins, R.G. Eichhorn, M. Ge, D. Gonnella, G.H. Hoffstaetter, M. Liepe, T.I. O'Connell, P. Quigley, D.M. Sabol, J. Sears, E.N. Smith, V. Veshcherevich
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  The main linac cryomodule (MLC) for the future energy-recovery linac (ERL) based X-ray light source at Cornell has been designed, fabricated, and tested. It houses six 7-cell SRF cavities with individual higher order-modes (HOMs) absorbers, cavity frequency tuners, and one magnet/BPM section. Cavities have achieved the specification values of 16.2MV/m with high-Q of 2.0·1010 in 1.8K in continuous wave (CW) mode. During initial MLC cavity testing, we encountered some field emission, reducing Q and lowering quench field. To overcome field emission and find optimal cool-down parameters, RF processing and thermal cycles with different cool-down conditions has been done. Here we report on these studies and present final results from the MLC cavity performance.  
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TUPLR012 HOM Measurements for Cornell's ERL Main Linac Cryomodule HOM, cavity, linac, simulation 496
 
  • F. Furuta, R.G. Eichhorn, M. Ge, D. Gonnella, G.H. Hoffstaetter, M. Liepe, P. Quigley, V. Veshcherevich
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  The main linac cryomodule (MLC) for a future energy-recovery linac (ERL) based X-ray source at Cornell has been designed, fabricated, and tested. It houses six 7-cell SRF cavities with individual higher order-modes (HOMs) absorbers, cavity frequency tuners, and one magnet/BPM section. All HOMs in MLC have been scanned in 1.8K. The results show effective damping of HOMs, and also agree well with simulation results and the previous HOM scan results on one 7-cell cavity prototype test cryomodule. Here we present detailed results from these HOM studies.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR012  
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TUPLR025 Optimal Nitrogen Doping Level to Reach High Q0 cavity, SRF, niobium, electron 523
 
  • D. Gonnella, T. Gruber, J.J. Kaufman, P.N. Koufalis, M. Liepe, J.T. Maniscalco
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  Funding: NSF and US DOE
New continuous wave (CW) accelerators such as LCLS-II at SLAC require many SRF cavities operating in the medium field region at unprecedented high Q. In order to achieve this demanding goal, nitrogen-doping of the SRF cavities will be used. Nitrogen-doping has been shown to affect the BCS resistance both by a lowering of Rbcs at low fields and by the introduction of an anti-Q slope which enables the Q to continue increasing as the RF field is increased. The exact strength of this anti-Q slope is heavily dependent on the doping recipe and specifically the mean free path of the RF penetration layer of the doped cavities. In addition to its effect on Rbcs, the mean free path affects the amount of residual resistance obtained due to trapped magnetic flux. We have analyzed nine cavities prepared with different levels of nitrogen-doping to understand how BCS and residual resistance are affected by changes in the mean free path. Here we present a model based on these experimental results to predict the optimal doping level to reach the maximum Q at 16 MV/m based on the ambient magnetic field conditions. We find that if the cavities can be cooled with small amounts of trapped flux, moderate nitrogen-doping is better, while if they will have large amounts of trapped flux, lighter dopings should be used.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR025  
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TUPLR027 Magnetic Field Management in LCLS-II 1.3 GHz Cryomodules cavity, vacuum, controls, shielding 527
 
  • S.K. Chandrasekaran, A. Grassellino, C.J. Grimm, G. Wu
    Fermilab, Batavia, Illinois, USA
 
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. De-AC02-07CH11359 with the United States Department of Energy.
The ambient magnetic field at the SRF cavity surface of the LCLS-II 1.3 GHz cryomodules is specified to be less than 0.5 μT (5 mG). Multiple methods were designed to lower the magnetic fields inside the prototype cryomodule. The resulting ambient magnetic field in this cryomodule just prior to its first cool down was <0.15 μT (1.5 mG), as measured using fluxgates inside and outside the cavity helium vessels.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR027  
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TUPLR028 Alternative Design for the RISP Pre-Stripper Linac linac, simulation, solenoid, cavity 531
 
  • B. Mustapha, Z.A. Conway, M.P. Kelly, P.N. Ostroumov, A.S. Plastun
    ANL, Argonne, USA
  • J.-H. Jang, H. Jin, H.J. Kim, J.-W. Kim
    IBS, Daejeon, Republic of Korea
 
  Funding: This work was supported by the work-for-other grant WFO8550H titled "Pre-conceptual design, cost and schedule estimate of the 18.5 MeV/u Pre-stripper linac for the RISP/IBS"
In a collaborative effort between Argonne's Linac Development Group and the RISP project team at the Korean Institute for Basic Science, we have developed an alternative design for the pre-stripper section of the RISP driver linac. The proposed linac design takes advantage of the recent accelerator developments at Argonne, namely the ATLAS upgrades and the Fermilab PIP-II HWR Cryomodule. In particular, the state-of-the-art performance of QWRs and HWRs, the integrated steering correctors and clean BPMs for a compact cryomodule design. To simplify the design and avoid frequency transitions, we used two types of QWRs at 81.25 MHz. The QWRs were optimized for β ~ 0.05 and ~ 0.11 respectively. Nine cryomodules are required to reach the stripping energy of 18.5 MeV/u. Following the lattice design optimization, end-to-end beam dynamics simulations including all sources of machine errors were performed. The results showed that the design is tolerant to errors with no beam losses observed for nominal errors. However, the robustness of the design could be further improved by a modified RFQ design, better optimized with the multi-harmonic buncher located upstream. This could lead to a significant reduction in the longitudinal beam emittance, offering much easier beam tuning and more tolerance to errors. The proposed design and the simulation results will be presented and discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR028  
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TUPLR029 FRIB HWR Tuner Development cavity, controls, alignment, cryogenics 535
 
  • S. Stark, A. Facco, S.J. Miller, P.N. Ostroumov, J.T. Popielarski, K. Saito, B.P. Tousignant, T. Xu
    FRIB, East Lansing, USA
  • A. Facco
    INFN/LNL, Legnaro (PD), Italy
  • S.M. Gerbick, M.P. Kelly
    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 State of Michigan and Michigan State University
During the last two years the HWR pneumatic tuner development at FRIB evolved from the first prototypes to the final production design. A lot of warm testing and several cryogenic integrated tests with cavity were performed to optimize the tuner features. The main challenges included the bellow bushings binding and very tight space limitations for the assembly on the rail. The final design, based on the acquired experience, was prepared in collaboration with ANL and entered the preproduction phase.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR029  
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TUPLR030 First FRIB β=0.53 Prototype Coldmasss Build cavity, vacuum, solenoid, SRF 538
 
  • D.R. Victory, K. Elliott, B. Oja, J.T. Popielarski, M.S. Wilbur
    FRIB, East Lansing, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE SC0000661, the State of Michigan and Michigan State University.
The β=0.53 coldmass consists of eight Superconducting Radio Frequency (SRF) β=0.53 cavities, eight Fundamental mode Power Couplers (FPC), and one 8 T solenoid. This is the first coldmass with this version of cavity and it has brought new challenges to overcome. The Facility for Rare Isotope Beams (FRIB) contains 18 cryomodules with β=0.53 cavity coldmasses, and this type of coldmass is the highest power and most produced ones in FRIB. During the final cleaning stage and the cavity assembly, particle detection equipment is used to verify the cavity cleanliness levels for cavity certification test and for coldmass assembly. This method allows for cleanliness detection of specific areas inside the cavity at any time a vacuum flange is off. The fixtures, techniques and procedures used to build the β=0.53 coldmasses will be presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR030  
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TUPLR033 First FRIB β=0.041 Production Coldmass Build cavity, solenoid, SRF, alignment 541
 
  • K. Elliott, S.J. Miller, B. Oja, J.T. Popielarski, L. Popielarski, D.R. Victory, M.S. Wilbur, T. Xu
    FRIB, East Lansing, USA
  • M. Wiseman
    JLab, Newport News, Virginia, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE SC0000661, the State of Michigan and Michigan State University.
Three β=0.041 cryomodules are required for the Facility for Rare Isotope Beams (FRIB) accelerator. Cleanroom assembly of all three coldmasses for these cryomodules has been completed. The cleanroom assembly includes; the superconducting radio frequency (SRF) cavities, the superconducting solenoids, fundamental power couplers (FPC), beam position monitors, alignment rail, and transport cart. This paper will provide an overview of the techniques and procedures used to assemble this cavity string such that it can be used in the FRIB accelerator.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR033  
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TUPLR048 Status and Lesson Learned from Manufacturing of FPC Couplers for the XFEL Program SRF, Windows, factory, status 572
 
  • S. Sierra, G. Garcin, Ch.L. Lievin, G. Vignette
    TED, Velizy-Villacoublay, France
  • A. Gallas, W. Kaabi
    LAL, Orsay, France
  • M. Knaak, M. Pekeler, L. Zweibaeumer
    RI Research Instruments GmbH, Bergisch Gladbach, Germany
 
  For the XFEL accelerator, Thales, RI research Instrument and LAL are working on the manufacturing, assembly and conditioning of Fundamental power couplers. 670 couplers has been manufactured. The main characteristics of these couplers are remained at 1.3 GHz. The paper describes the full production activity from the starting of the program We describe the lesson learned from a mass production of FPC coupler and different steps necessaries for obtaining a rate up to 10 couplers a week. we propose also some other way to be optimized for a future possible mass production of such components. With comparison of processes and adaptation which could benefit to an increase rate, if needed, including some of them which could be studies from the coupler definition to the manufacturing process in order to obtain a stable and possible increased rate or lower cost of production by decreasing the risks on programs. The status of the production curve during the program is also given  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR048  
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TUPLR061 Cryomodule and Power Coupler for RIKEN Superconducting QWR cavity, vacuum, linac, SRF 598
 
  • K. Ozeki, O. Kamigaito, H. Okuno, N. Sakamoto, K. Suda, Y. Watanabe, K. Yamada
    RIKEN Nishina Center, Wako, Japan
  • E. Kako, H. Nakai, K. Umemori
    KEK, Ibaraki, Japan
  • K. Okihira
    MHI, Hiroshima, Japan
  • K. Sennyu, T. Yanagisawa
    MHI-MS, Kobe, Japan
 
  In RIKEN Nishina Center, we are constructing a prototype of low-beta superconducting QWR for ions. Presently, the designs of cryomodule, which contains two QWRs, and power coupler are being carried out. In this contribution, the progress situation for the construction of cryomodule and power coupler will be reported. This work was funded by ImPACT Program of Council for Science, Technology and innovation (Cabinet Office, Government of Japan).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR061  
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TUPLR067 Solenoid/Magnetic Shielding Test Results in FRIB-1&2 Cryomodules solenoid, cavity, shielding, dipole 607
 
  • D. Luo, H. Ao, E.E. Burkhardt, J. Casteel, A. Ganshyn, W. Hartung, M.J. Holcomb, J.T. Popielarski, K. Saito, S. Shanab, E. Supangco, M. Thrush
    FRIB, East Lansing, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661, the State of Michigan and Michigan State University.
Recently we did bunker tests for FRIB first cryomodule (CM-1) and second one (CM-2) which houses 0.085 QWRs and solenoid packages. Their performances were successfully validated in the full configuration. This paper reports the solenoid package tests results.
 
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TUPLR072 Fabrication and Low Temperature Test Plan for Rare Isotope Science Project SRF, cavity, radiation, linac 619
 
  • W.K. Kim, M.J. Joung, Y. Jung, H. Kim, J.-W. Kim, Y. Kim, I. Shin
    IBS, Daejeon, Republic of Korea
 
  Quarter-wave resonator (QWR), half-wave resonator (HWR) and single-spoke resonator (SSR) cryomodules are used for RAON accelerator. The layout of RAON accelerator and three types of cryomodules such as QWR, HWR and SSR are shown in the linac. SRF test facility which consists of cryoplant, cleanroom, vertical test facility and horizontal test facility is constructed. Cleanroom has high pressure rinsing (HPR), ultrasonic cleaning (USC), buffered chemical polishing (BCP), high vacuum furnace and cavity assemble place. The test plan for cavity and cryomodules is presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR072  
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TUPLR073 Development of RAON QWR Cryomodule for Linac Demonstration linac, cavity, PLC, controls 622
 
  • H. Kim, J.W. Choi, Y.W. Jo, Y. Jung, W.K. Kim, Y. Kim, M. Lee
    IBS, Daejeon, Republic of Korea
 
  Quarter-wave resonator (QWR) cryomodule is developed for linac demonstraction. The plan and layout of the linac demonstration are shown. 3D drawing and P&ID are shown for the quarter-wave resonator (QWR) cryomodule. The QWR cryomodule consists of cavity, coupler, tuner, liquid helium reservoir, thermal shield and magnetic shield. PLC rack is fabricated to control the QWR cryomodules. The PLC controls and monitors pumps, heaters, cryogenic valves, solenoid valves, gate valves and temperature sensors.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR073  
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TUP106001 Magnetic Field Measurements in a Cryomodule with Nearby Warm-Section Quadrupole Magnets of RAON Heavy Ion Accelerator shielding, cavity, ion, heavy-ion 625
 
  • H.J. Cha, J.W. Choi, I. Chun, M. Lee
    IBS, Daejeon, Republic of Korea
 
  For the Korean heavy ion accelerator RAON, a normal-conducting quadrupole magnet doublet with an intermediate beam diagnostic devices between two cryomodules is served for collimating the heavy ion beam. Although the fringe field of a magnet at a superconducting cavity position is low enough, differently from a strong superconducting solenoid, it can degrade the acceleration performance in the case of quench of the cavity directly and/or indirectly by contaminating the cryomodule wall and magnetic shields. In this study, we analyze the magnetic measurement results in the cryomodule assembled with the magnet doublet compared to the calculated ones and discuss the future plan.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUP106001  
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TUP106006 Vertical Test Results on ESS Medium Beta Elliptical Cavity Prototype cavity, linac, SRF, status 631
 
  • E. Cenni
    CEA/IRFU, Gif-sur-Yvette, France
  • S. Berry, P. Bosland, F. Éozénou, L. Maurice, J. Plouin, C. Servouin
    CEA/DSM/IRFU, France
  • G. Costanza
    Lund University, Lund, Sweden
  • C. Darve
    ESS, Lund, Sweden
  • G. Devanz, X. Hanus, F. Peauger, D. Roudier
    CEA/DRF/IRFU, Gif-sur-Yvette, France
 
  The ESS elliptical superconducting Linac consists of two types of 704.42 MHz cavities, medium and high beta, to accelerate the beam from 216 MeV (spoke cavity Linac) up to the final energy at 2 GeV. The last Linac optimization, called Optimus+ [1], has been carried out taking into account the limitations of SRF cavity performance (field emission). The medium and high-beta parts of the Linac are composed of 36 and 84 elliptical cavities, with geometrical beta values of 0.67 and 0.86 respectively. This work presents the latest vertical test results on ESS medium beta elliptical cavity prototypes. We describe the cavity preparation procedure from buffer chemical polishing to vertical test. Finally magnetic probes (Fluxgate) were installed on the cavity to determine magnetic field background during vertical test. The latest vertical test results showed that our cavity design performance are beyond requirements.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUP106006  
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TUP106024 Optimizing Cavity Choice for FRIB Energy Upgrade Plan cavity, ion, linac, heavy-ion 637
 
  • S. Shanab, K. Saito, Y. Yamazaki
    FRIB, East Lansing, USA
 
  Isotope production yield rate is directly proportional to beam power, especially for heavy ions. Higher beam kinetic energy on target drives more isotope yield. FRIB has an energy upgrade plan up to ≥ 400 MeV/u for Uranium and already prepared a vacant space in the design stage and cryogenic capacity that accommodates for the energy upgrade plan[1]. This upgrade requires an optimized linac design and challenging technology for cavity performance improvement. In this paper, we will approach this issue concerning; maximizing final energy, optimum beta, cavity operating frequency, cryogenic power, fabrication and cost in order to develop a cavity that is suitable for the energy upgrade plan.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUP106024  
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WE1A01 PIP-II Injector Test: Challenges and Status rfq, operation, solenoid, SRF 641
 
  • P. Derwent, J.-P. Carneiro, J.P. Edelen, V.A. Lebedev, L.R. Prost, A. Saini, A.V. Shemyakin, J. Steimel
    Fermilab, Batavia, Illinois, USA
 
  The Proton Improvement Plan II (PIP-II) at Fermilab is a program of upgrades to the injection complex. At its core is the design and construction of a CW-compatible, pulsed H superconducting RF linac. To validate the concept of the front-end of such machine, a test accelerator known as PXIE is under construction. It includes a 10 mA DC, 30 keV H ion source, a 2 m-long Low Energy Beam Transport (LEBT), a 2.1 MeV CW RFQ, followed by a Medium Energy Beam Transport (MEBT) that feeds the first of 2 cryomodules increasing the beam energy to about 25 MeV, and a High Energy Beam Transport section (HEBT) that takes the beam to a dump. The ion source, LEBT, RFQ, and initial version of the MEBT have been built, installed, and commissioned. This report presents the overall status of the PXIE warm front end, including results of the beam commissioning through the installed components, and progress with SRF cryomodules and other systems.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-WE1A01  
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WE1A02 Assembly of XFEL Cryomodules: Lessons and Results cavity, vacuum, controls, HOM 646
 
  • S. Berry, O. Napoly
    CEA/DSM/IRFU, France
 
  The industrialized string and module assembly of 103 European XFEL cryomodules has been performed at CEA-Saclay between September 2012 and the spring of 2016. The general features and achievements of this construction project will be reviewed, including lessons learned regarding organization, industrial transfer, quality control and assembly procedures. An overview of the cryomodule performance and RF test results will be presented.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-WE1A02  
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WE1A03 The Superconducting Radio-Frequency Linear Accelerator Components for the European Spallation Source: First Test Results cavity, SRF, linac, proton 651
 
  • C. Darve, N. Elias, F. Schlander
    ESS, Lund, Sweden
  • C. Arcambal, P. Bosland, E. Cenni, G. Devanz
    CEA/IRFU, Gif-sur-Yvette, France
  • S. Bousson, P. Duthil, G. Olivier, G. Olry, D. Reynet
    IPN, Orsay, France
  • G. Costanza
    Lund University, Lund, Sweden
  • H. Li, R.J.M.Y. Ruber, R. Santiago Kern
    Uppsala University, Uppsala, Sweden
  • F. Peauger
    CEA/DSM/IRFU, France
 
  The European Spallation Source requires a pulsed Linac with an average beam power on the target of 5MW which is about five times higher than the most powerful spallation source in operation today. Over 97% of the acceleration occurs in superconducting cavities. ESS will be the first accelerator to employ double spoke cavities to accelerate beam. Accelerating gradients of 9MV/meter is required in the spoke section. The spoke section will be followed by 36 elliptical 704 MHz cavities with a geometrical beta of 0.67 and elliptical 704 MHz cavities with a geometrical beta of 0.86. Accelerating gradients of 20MV/m is required in the elliptical section. Initial gradient test results will be presented in which results exceed expected requirements.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-WE1A03  
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WE1A04 Performance Analysis of the European XFEL SRF Cavities, From Vertical Test to Operation in Modules cavity, linac, SRF, controls 657
 
  • N. Walker, D. Reschke, J. Schaffran, L. Steder, M. Wenskat
    DESY, Hamburg, Germany
  • L. Monaco
    INFN/LASA, Segrate (MI), Italy
 
  More than 800 resonators have been fabricated, vertically qualified and operated in module tests before the accelerating module installation in the linac, which will be completed before the conference. An analysis of this experience, with correlation of the final cavity performances with production, preparation and assembly stages, is underway and at the time of the conference a summary of the activities will be available.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-WE1A04  
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WE1A05 HIE-ISOLDE SC Linac Progress and Commissioning in 2016 cavity, linac, coupling, cryogenics 663
 
  • W. Venturini Delsolaro, E. Bravin, N. Delruelle, M. Elias, E. Fadakis, J.A. Ferreira Somoza, F. Formenti, M.A. Fraser, J. Gayde, N. Guillotin, Y. Kadi, G. Kautzmann, T. Koettig, Y. Leclercq, M. Martino, M. Mician, A. Miyazaki, E. Montesinos, V. Parma, J.A. Rodriguez, S. Sadovich, E. Siesling, D. Smekens, M. Therasse, L. Valdarno, D. Valuch, G. Vandoni, U. Wagner, P. Zhang
    CERN, Geneva, Switzerland
 
  The HIE-ISOLDE project (High Intensity and Energy ISOLDE) reached an important milestone in October 2015 when the first physics run was carried out with radioactive Zn beams at 4 MV/m. This is a first stage in the upgrade of the REX post-accelerator, whereby the energy of the radioactive ion beams was increased from 3 to 4.3 MeV per nucleon. The facility will ultimately be equipped with four high-beta cryomodules that will accelerate the beams up to 10 MeV per nucleon for the heaviest isotopes available at ISOLDE. The first cryomodule of the new linac, hosting five superconducting cavities and one solenoid, was commissioned in summer 2015, while the second one was being assembled in clean room. The new high-energy beam transfer lines were installed and commissioned in the same lapse of time. Commissioning with two cryomodules is planned for Summer 2016 to prepare for a physics run at 5.5 MeV/u in the second half of the year. This contribution will focus on the results of the commissioning and operation of the SC linac in 2015. Plans for the second phase of the HIE-ISOLDE project will be highlighted.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-WE1A05  
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WE2A02 FRIB Cryomodule Design and Production linac, cavity, SRF, alignment 673
 
  • T. Xu, H. Ao, B. Bird, N.K. Bultman, E.E. Burkhardt, F. Casagrande, C. Compton, J.L. Crisp, K.D. Davidson, K. Elliott, A. Facco, V. Ganni, A. Ganshyn, W. Hartung, M. Ikegami, P. Knudsen, S.M. Lidia, I.M. Malloch, S.J. Miller, D.G. Morris, P.N. Ostroumov, J.T. Popielarski, L. Popielarski, M.A. Reaume, K. Saito, S. Shanab, G. Shen, M. Shuptar, S. Stark, J. Wei, J.D. Wenstrom, M. Xu, Y. Xu, Y. Yamazaki, Z. Zheng
    FRIB, East Lansing, Michigan, USA
  • A. Facco
    INFN/LNL, Legnaro (PD), Italy
  • K. Hosoyama
    KEK, Ibaraki, Japan
  • M.P. Kelly
    ANL, Argonne, Illinois, USA
  • R.E. Laxdal
    TRIUMF, Vancouver, Canada
  • M. Wiseman
    JLab, Newport News, Virginia, USA
 
  Funding: U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
The Facility for Rare Isotope Beams (FRIB), under con-struction at Michigan State University, will utilize a driver linac to accelerate stable ion beams from protons to ura-nium up to energies of >200 MeV per nucleon with a beam power of up to 400 kW. Superconducting technology is widely used in the FRIB project, including the ion sources, linac, and experiment facilities. The FRIB linac consists of 48 cryomodules containing a total of 332 superconducting radio-frequency (SRF) resonators and 69 superconducting solenoids. We report on the design and the construction of FRIB cryomodules.
 
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-WE2A02  
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WE2A03 Plasma Processing to Improve the Performance of the SNS Superconducting Linac plasma, linac, cavity, accelerating-gradient 679
 
  • M. Doleans, R. Afanador, J.A. Ball, D.L. Barnhart, W. Blokland, M.T. Crofford, B. DeGraff, S.W. Gold, B.S. Hannah, M.P. Howell, S.-H. Kim, S.W. Lee, J.D. Mammosser, C.J. McMahan, T.S. Neustadt, J. Saunders, S.E. Stewart, W.H. Strong, P.V. Tyagi, D.J. Vandygriff, D.M. Vandygriff
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: This work was supported by SNS through UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. DOE.
An in-situ plasma processing technique has been developed at the Spallation Neutron Source (SNS) to improve the performance of the superconducting radio-frequency (SRF) cavities in operation. The technique uses a low-density reactive neon-oxygen plasma at room-temperature to improve the surface work function, to help removing adsorbed gases on the RF surface and to reduce its secondary emission yield. Recently, the plasma processing technique has been applied to one offline cryomodule and to two cryomodules in the linac tunnel. Improvement of the accelerating gradient has been observed in all three cryomodules.
 
slides icon Slides WE2A03 [4.433 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-WE2A03  
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THOP10 Design and Commissioning of FRIB Multipacting-Free Fundamental Power Coupler electron, cavity, controls, impedance 767
 
  • Z. Zheng, J.T. Popielarski, K. Saito, S. Stark, T. Xu, Y. Yamazaki
    FRIB, East Lansing, USA
 
  Funding: *Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
The original Fundamental Power Coupler (FPC) of Half-Wave Resonator (HWR) for the Facility of Rare Isotope Beams (FRIB) requires multipacting conditioning at operating RF power which is up to 5 kW Continue Wave (CW). Conditioning takes a lot of time and RF power, and its elimination is highly desirable. To significantly shorten the RF conditioning, we developed a multipacting-free coupler design. This paper reports the latest progress in the optimization and prototype tests of multipacting-free coupler. The choke structure is removed and coupler geometry is further modified to protect the coupler RF window from the electron bombardment. The comparison result of multipacting-free coupler with original coupler was performed on automatic conditioning system, which showed significantly time reducing for RF conditioning.
 
slides icon Slides THOP10 [2.442 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THOP10  
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THPRC008 Status of the Development and Manufacturing of LCLS-II Fundamental Power Couplers SRF, status, Windows, factory 782
 
  • S. Sierra, G. Garcin, Ch.L. Lievin, C. Ribaud, G. Vignette
    TED, Velizy-Villacoublay, France
  • M. Knaak, A. Navitski, M. Pekeler, L. Zweibaeumer
    RI Research Instruments GmbH, Bergisch Gladbach, Germany
 
  For the LCLS-II project, Thales and RI research Instrument are working on the manufacturing and assembly of the Fundamental Power Couplers. The paper describes the production of the Fundamental Power Couplers for the LCLS-II project. The main characteristics of these couplers are remained at 1.3 GHz. It describes the main challenges to be overcome principally on the Warm Internal conductor, with a thickness of copper of 150μm. The results obtained on this coating We describe the results obtained on the prototype phase and the status of the serial production on the date of the paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPRC008  
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THPRC014 RF Losses in 1.3 GHz Cryomodule of The LCLS-II Superconducting CW Linac HOM, linac, cavity, cryogenics 798
 
  • A. Saini, A. Lunin, N. Solyak, A.I. Sukhanov, V.P. Yakovlev
    Fermilab, Batavia, Illinois, USA
 
  The Linac Coherent Light Source (LCLS) is an x-ray free electron laser facility. The proposed upgrade of the LCLS facility is based on construction of a new 4 GeV superconducting (SC) linac that will operate in continuous wave (CW) mode. The major infrastructure investments and the operating cost of a SC CW linac are outlined by its cryogenic requirements. Thus, a detail understanding of RF losses in the cryogenic environment is critical for the entire project. In this paper we review RF losses in a 1.3 GHz accelerating cryomodule of the LCLS-II linac. RF losses due to various sources such untrapped higher order modes (HOMs), resonant losses etc. are addressed and presented here.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPRC014  
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THPRC015 Cool-Down Performance of the Cornell ERL Cryomodules cavity, linac, operation, cryogenics 802
 
  • R.G. Eichhorn, F. Furuta, M. Ge, G.H. Hoffstaetter, M. Liepe, S.R. Markham, T.I. O'Connell, P. Quigley, D.M. Sabol, J. Sears, E.N. Smith, V. Veshcherevich, D. Widger
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  In the framework of the ERL prototyping, Cornell University has built two cryomodules, one injector module and one prototype Main Linac Cryomodule (MLC). In 2015, the MLC was successfully cooled down for the first time. We will report details on the cool-down as well as cycle tests we did in order to achieve slow and fast cool-down of the cavities. We will also report on the improvement we made on the injector cryomodule which also included a modification of the heat exchanger can that allows now a more controlled cool-down, too.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPRC015  
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THPRC017 Performance of SRF Cavity Tuners at LCLS II Prototype Cryomodule at FNAL cavity, SRF, operation 808
 
  • J.P. Holzbauer, Y.M. Pischalnikov, W. Schappert, J.C. Yun
    Fermilab, Batavia, Illinois, USA
 
  Performances of the fast/slow tuners mounted on the 8 SRF cavities of first LCLS-II prototype cryomodule assembled at FNAL will be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPRC017  
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THPRC021 Status of β=0.53 Pre-Production Cryomodule cavity, linac, SRF, alignment 811
 
  • H. Ao, B. Bird, G.D. Bryant, B. Bullock, N.K. Bultman, C. Compton, A. Facco, J.D. Hulbert, S.J. Miller, J.T. Popielarski, L. Popielarski, M.A. Reaume, K. Saito, M. Shuptar, J. Simon, S. Stark, B.P. Tousignant, J.D. Wenstrom, K. Witgen, T. Xu, Z. Zheng
    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 driver linac for the Facility for Rare Isotope Beams (FRIB) comprises four kinds of cavities (=0.041, 0.085, 0.29, and 0.53) and six types of cryomodules including matching modules. FRIB has started the fabrication of a β=0.53 preproduction cryomodule, which is the first prototype for a half-wave (=0.29 and 0.53) cavity. This paper describes the fabrication progress and the lessons learned from the β=0.53 preproduction cryomodule.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPRC021  
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THPRC022 The Cryogenic Performance of the ARIEL E-Linac Cryomodules cavity, linac, TRIUMF, cryogenics 815
 
  • Y. Ma, K. Fong, P.R. Harmer, T. Junginger, D. Kishi, A.N. Koveshnikov, R.E. Laxdal, N. Muller, Z.Y. Yao, V. Zvyagintsev
    TRIUMF, Vancouver, Canada
  • E. Thoeng
    UBC & TRIUMF, Vancouver, British Columbia, Canada
 
  The Advanced Rare Isotope Laboratory (ARIEL) project at TRIUMF requires a 50 MeV superconducting electron Linac consisting of five nine cell 1.3 GHz cavities divided into three cryomodules with one, two and two cavities in each module respectively. The cryomodule design utilizes a unique box cryomodule with a top-loading cold mass. LHe is distributed in parallel to each cryomodule at 4 K and at ~1.2 bar. Each cryomodule has a cryogenic insert on board that receives the 4 K liquid and produces 2 K liquid into a cavity phase separator. In the cryomodules the natural two-phase convection loops, i.e. siphon loop, are installed which supply 4 K liquid to thermal intercepts and return the vaporized liquid to the 4 K reservoir as a refrigerator load. The design of the cryomodule, the simulation results with Ansys Fluent and the results of the cold tests will be presented.
mayanyun@triumf.ca
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPRC022  
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THPRC023 Cost Reduction for FRIB Magnetic Shielding shielding, cavity, cryogenics, simulation 818
 
  • Z. Zheng, J.T. Popielarski, K. Saito, T. Xu
    FRIB, East Lansing, USA
 
  Funding: *Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
Cryogenic magnetic shielding (A4K) is generally used in SRF cryomodules which is much more expensive than mu-metal used in room temperature. In order to reduce the cost, FRIB QWR and HWR magnetic shieldings were redesign to improve the shielding performance so that mu-metal can be implemented as an alternative shielding material. The magnetic shielding of first FRIB β=0.085 cryomodule was made up of 50% by A4K and 50% by mu-metal. Cavities were tested in 4K and 2K, the results showed that the Q0 of cavities were similar for both shielding materials, which is a success as a validation test for mu-metal magnetic shielding.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPRC023  
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THPRC024 Polarity Check of the FRIB Cryomodule Solenoids by Measuring Leakage Magnetic Field solenoid, dipole, vacuum, linac 821
 
  • H. Ao, D. Luo, F. Marti, K. Saito, S. Shanab
    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.
We observed the outside magnetic field of the first β=0.085 production cryomodule while a solenoid and steering dipoles are under operation. This measurement aims to check the polarity on these magnets after the final installation in the accelerating tunnel. This paper also shows the residual magnetic field variation through the degaussing process of these magnets.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPRC024  
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THPLR027 Progress Towards a 2.0 K Half-Wave Resonator Cryomodule for Fermilab's PIP-II Project vacuum, cavity, linac, SRF 906
 
  • Z.A. Conway, A. Barcikowski, G.L. Cherry, R.L. Fischer, B.M. Guilfoyle, C.S. Hopper, M. Kedzie, M.P. Kelly, S.H. Kim, S.W.T. MacDonald, P.N. Ostroumov, T. Reid
    ANL, Argonne, Illinois, USA
  • V.A. Lebedev, A. Lunin
    Fermilab, Batavia, Illinois, USA
 
  Funding: This material is supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics and Office of High-Energy Physics, Contracts No. DE-AC02-76-CH03000 and DE-AC02-06CH11357.
In support of Fermilab's Proton Improvement Plan-II project Argonne National Laboratory is constructing a superconducting half-wave resonator cryomodule. This cryomodule is designed to operate at 2.0 K, a first for low-velocity ion accelerators, and will accelerate ≥1 mA proton/H beams from 2.1 to 10.3 MeV. Since 2014 the construction of 9 162.5 MHz b = 0.112 superconducting half-wave resonators, the vacuum vessel and the majority of the cryomodule subsystems have been finished. Here we will update on the status of this work and report on preliminary cavity test results. This will include cavity performance measurements where we found residual resistances of < 3 nanoOhms at low fields and peak voltage gains of 5.9 MV, which corresponds to peak surface fields of 134 MV/m and 144 mT electric and magnetic respectively.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR027  
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THPLR030 Performances of the Two First Single Spoke Prototypes for the MYRRHA Project cavity, simulation, superconductivity, linac 916
 
  • D. Longuevergne, J.-L. Biarrotte, S. Blivet, P. Duchesne, G. Olry, H. Saugnac
    IPN, Orsay, France
  • Y. Gómez Martínez
    LPSC, Grenoble Cedex, France
 
  Funding: This work is being supported by the Euratom research and training program 2014-2018 under grant agreement N°662186 (MYRTE project)
The MYRRHA project aims at the construction of an accelerator driven system (ADS) at MOL (Belgium) for irradiation and transmutation experiment purposes. The facility will feature a superconducting LINAC able to produce a proton flux of 2.4 MW (600 MeV - 4 mA). The first section of the superconducting LINAC will be composed of 352 MHz (β = 0.37) Single Spoke Resonators (SSR) housed in short cryomodules operating at 2K. After a brief presentation of the cryomodule design, this paper will aim at presenting the RF performances of the SSR tested in vertical cryostat in the framework of European MYRTE project (MYRRHA Research and Transmutation Endeavour) and at comparing experimental results (Lorentz forces, pressure sensitivity, multipacting barriers…) to simulated values.
 
poster icon Poster THPLR030 [1.610 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR030  
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THPLR040 First Vertical Test of Superconducting QWR Prototype at RIKEN ion, coupling, acceleration, multipactoring 939
 
  • K. Yamada, O. Kamigaito, K. Ozeki, N. Sakamoto, K. Suda, Y. Watanabe
    RIKEN Nishina Center, Wako, Japan
  • E. Kako, H. Nakai, K. Umemori
    KEK, Ibaraki, Japan
  • A. Miyamoto, K. Sennyu, T. Yanagisawa
    MHI-MS, Kobe, Japan
 
  Development of a superconducting quarter-wavelength resonator (SC-QWR) was started at RIKEN Nishina Center to realize a low-velocity part of high-intensity ion linac. First prototype of the SC-QWR, frequency of which is 75.5 MHz, is fabricating now*. Preparation of its partial components such as outer conductor, stem, bottom plate, and top plate was almost completed, and we are now studying a low-power RF property by clamping the every components as an assembly to obtain data for frequency tuning. After the adjustment of geometry of components and welding them, surface treatment by buffered chemical polishing and high-pressure rinsing will be performed in the summer. Preparation of vertical test for the SC-QWR is also in progress at KEK. The first result of vertical test for the prototype of SC-QWR will be presented in this contribution. This work was funded by the ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan).
* N. Sakamoto et al., Proceedings of SRF2015, WEBA06.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR040  
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THPLR041 650 MHz Elliptical Superconducting RF Cavities for PIP-II Project cavity, linac, controls, beam-transport 943
 
  • I.V. Gonin, E. Borissov, A. Grassellino, C.J. Grimm, V. Jain, S. Kazakov, V.A. Lebedev, A. Lunin, C.S. Mishra, D.V. Mitchell, T.H. Nicol, Y.M. Pischalnikov, G.V. Romanov, A.M. Rowe, N.K. Sharma, N. Solyak, V.P. Yakovlev
    Fermilab, Batavia, Illinois, USA
 
  The PIP-II 800 MeV linac employs 650 MHz elliptical 5-cell CW-capable cavities to accelerate up to 2 mA peak beam current of H in the energy range 185 - 800 MeV. The low beta (LB) βG = 0.61 portion should accelerate from 185 MeV-500 MeV using 33 LB dressed cavities in 11 cryomodules. The high beta (HB) βG = 0.92 portion of the linac should accelerate from 500 to 800 MeV using 24 HB dressed cavities in 4 cryomodules. The development of both LB and HB cavities is going on under IIFC collaboration. The development of LB cavity initiated at VECC Kolkatta and HB cavity is going at RRCAT, Indore. This paper present design methodology adopted starting from RF design to get mechanical dimensions of the RF cells and then explains dressing of the cavity for both low beta and high beta cavities. Further the tuner design and its integration to the dressed cavity is discussed. Paper also explains the salient design features of these dressed cavities.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR041  
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THPLR069 Quality Factor Measurement Method Using Multi Decay Time Constants on Cavity cavity, pick-up, superconducting-cavity, coupling 1011
 
  • J.W. Kim, H. Kim
    IBS, Daejeon, Republic of Korea
 
  Quality factor measurement method using multi decay time constants on superconducting cavity is suggested. In most cases of vertical test, one decay time constant is measured around critical coupling and coupling constants are measured using forward and reflected rf power to get intrinsic quality factor. We use multi decay time constants method to measure the quality factor, which uses three decay time constants. Two more switches before and after the cavity are added to the measurement system. Decay time constants are measured by switching off the rf power switch in front of rf source, the forward power switch in front of input power coupler, and then the pickup power switch behind the pickup coupler, respectively, at the same power of steady state.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR069  
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