Keyword: cryomodule
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SUPCAV018 First N-Doping and Mid-T Baking of Medium-ß 644 MHz 5-Cell Elliptical Superconducting RF Cavities for Michigan State University’s Facility for Rare Isotope Beams cavity, cathode, SRF, linac 53
 
  • K.E. McGee, S.H. Kim, P.N. Ostroumov, A. Taylor
    FRIB, East Lansing, Michigan, USA
  • G.V. Eremeev, M. Martinello, A.V. Netepenko
    Fermilab, Batavia, Illinois, USA
  • M.P. Kelly, T. Reid
    ANL, Lemont, Illinois, USA
  
  Funding: Work supported by the 2020 US DoE, Office of Science Graduate Student Research award (SCGSR), and US DoE, Office of Science, High Energy Physics under Cooperative Agreement award number DE-SC0018362
Two hadron linacs currently under development in the US, the PIP-II linac at Fermi National Accelerator Laboratory (FNAL) and the upgrade for Michigan State University’s Facility For Rare Isotope Beams (FRIB), will employ 650 and 644 MHz ß-0.6 elliptical superconducting cavities respectively to meet their design energy requirements. The desired CW operation modes of these two linacs sets Q-factor requirements well above any previously achieved for cavities at this operating frequency and velocity, driving the need to explore new high-Q treatments. The N-doping technique developed at FNAL and employed at an industrial scale to the LCLS-II cryomodules is a strong candidate for high-Q treatments, but work is needed to refine the treatment to the lower operating frequency and velocity regime. We present the first results of the first N-doping tests and a "mid-T" bake test in the FRIB 644 MHz 5-cell elliptical cavities. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPCAV018  
About • Received ※ 23 June 2021 — Revised ※ 16 November 2021 — Accepted ※ 08 May 2022 — Issue date ※ 08 May 2022
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SUPTEV008 CW Operation of Conduction-Cooled Nb3Sn SRF Cavity cavity, SRF, operation, controls 133
 
  • N.A. Stilin, A.T. Holic, M. Liepe, R.D. Porter, J. Sears, Z. Sun
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  
  Significant progress in the performance of SRF cavities coated with Nb3Sn films during the last few years has provided an energy efficient alternative to traditional Nb cavities, thereby initiating a fundamental shift in SRF technology. These Nb3Sn cavities can operate at significantly higher temperatures than Nb cavities while simultaneously requiring less cooling power. This allows for the use of new cryogenic cooling schemes based on conduction cooling with robust, commercialized turn-key style cryocoolers. Cornell University has developed and tested a 2.6 GHz Nb3Sn cavity assembly which utilizes such cooling methods. These tests have demonstrated stable RF operation at 10 MV/m with measured thermal dynamics which match numerical simulations. These results also serve as a foundation for designing a new standalone SRF cryomodule which will use a pair of cryocoolers to cool a 1.3 GHz Nb3Sn cavity with an input coupler capable of supporting high beam current operation.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPTEV008  
About • Received ※ 22 June 2021 — Accepted ※ 13 August 2021 — Issue date ※ 08 November 2021  
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SUPTEV014 SRF Cavity Tuners for 3.9 GHz Cryomodules for LCLS-II Project cavity, operation, SRF, FEL 155
 
  • C. Contreras-Martinez
    FRIB, East Lansing, Michigan, USA
  • T.T. Arkan, T.N. Khabiboulline, Y.M. Pischalnikov, G.V. Romanov, R.P. Stanek, J.C. Yun
    Fermilab, Batavia, Illinois, USA
  
  Fermilab conducted testing of three 3.9 GHz cryomodules for the LCLS-II project that will operate in continuous wave mode. A fast/fine tuning component was added to the LCLS-II 3.9 GHz tuner design due to the cavity bandwidth of 130 Hz which consists of two encapsulated piezos. Several cavities faced problems with fast-tuner operations after cooldown to 2 K and tuning the cavities to 3.9 GHz in cryomodule 2. All the piezo actuators were in working conditions but the slow tuner ranges required to stretch some of the cavities to the operational 3.9 GHz frequency were too small to deliver the required preload on the piezos. This behavior can be attributed to several factors: setting the initial warm cavity frequency during production too high, pressure tests of the warm cryomodule could have changed cavity frequency; and the small bending and twisting of the cavity-tuner system during the cooldown and warmup of the cavities. A decision was made to inelastically retune the warm cavities to decrease the unrestrained frequency by 200-300 kHz, this was done via the slow tuner. The results for this retuning method of three 3.9GHz cryomodules will be discussed.  
poster icon Poster SUPTEV014 [0.720 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPTEV014  
About • Received ※ 22 June 2021 — Accepted ※ 23 January 2022 — Issue date ※ 09 April 2022  
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MOOFAV02 Status of the RAON Superconducting Linear Accelerator cavity, MMI, linac, cryogenics 175
 
  • Y.U. Sohn, T.Y. Ki, Y. Kim, M. Lee, K.T. Seol
    IBS, Daejeon, Republic of Korea
  
  Funding: Ministry of Science and ICT (MSIT)
RAON, being constructed as the Rare Isotope Science Project (RISP) by the Institute for Basic Science (IBS) since 2011 is a flagship heavy ion accelerator facility in Korea to promote fundamental science and application of isotope nuclei and related science. The installation of the heavy ion accelerator systems including injector, rare isotope (RI) production systems, and experimental systems are currently being progressed toward to commissioning of RAON, while the civil construction of the RAON site in Shindong, Daejeon of Korea, is going to finish in 2021. The superconducting LINAC with low energy, so-call SCL3 as the 1st phase will be commissioned on the December of 2021. The overview RAON accelerator facility and status of RISP are reported in this paper. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOOFAV02  
About • Received ※ 26 August 2021 — Accepted ※ 05 April 2022 — Issue date ※ 16 May 2022  
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MOOFAV05 Proton Improvement Plan – II: Overview of Progress in the Construction cavity, SRF, linac, operation 182
 
  • A.L. Klebaner, C. Boffo, S.K. Chandrasekaran, D. Passarelli, G. Wu
    Fermilab, Batavia, Illinois, USA
  
  Funding: US Department of Energy
The Proton Improvement Plan II (PIP-II) project is an essential upgrade to Fermilab’s particle accelerator complex to enable the world’s most intense neutrino beam for LBNF/DUNE and a broad particle physics program for many decades to come. PIP-II will deliver 1.2 MW of proton beam power from the Main Injector, upgradeable to multi-MW capability. The central element of PIP-II is an 800 MeV linac, which comprises a room temperature front end followed by an SRF accelerator. The front end has been constructed and operated with (pulsed & CW) beam in the PIP-II Injector Test facility (PIP2IT). The SRF accelerator consists of five different types of cavities/cryomodules, including Half Wave Resonators (HWR), Single Spoke and elliptical resonators operating at state-of-the-art parameters. The first two PIP-II cryomodules, HWR and Single Spoke Resonator 1 (SSR1) are installed in PIP2IT and have accelerated beam to 17 MeV. PIP-II is the first U.S. accelerator project that will be constructed with significant contributions from international partners, including India, Italy, France, United Kingdom and Poland. The project was recently baselined, and site construction is underway 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOOFAV05  
About • Received ※ 13 August 2021 — Revised ※ 14 January 2022 — Accepted ※ 21 February 2022 — Issue date ※ 13 March 2022
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MOOFAV10 Completion of FRIB Superconducting Linac and Phased Beam Commissioning linac, cavity, MMI, SRF 197
 
  • T. Xu, Y. Al-Mahmoud, H. Ao, J. Asciutto, B. Bird, J. Bonofiglio, B. Bullock, N.K. Bultman, F. Casagrande, W. Chang, Y. Choi, C. Compton, J.C. Curtin, K.D. Davidson, K. Elliott, A. Facco, V. Ganni, A. Ganshyn, J. Gao, P.E. Gibson, Y. Hao, W. Hartung, N.M. Hasan, L. Hodges, K. Holland, J.D. Hulbert, M. Ikegami, T. Kanemura, S.H. Kim, P. Knudsen, Z. Li, S.M. Lidia, G. Machicoane, C. Magsig, P.E. Manwiller, F. Marti, T. Maruta, K.E. McGee, E.S. Metzgar, S.J. Miller, D.G. Morris, H. Nguyen, P.N. Ostroumov, A.S. Plastun, J.T. Popielarski, L. Popielarski, X. Rao, M.A. Reaume, H.T. Ren, K. Saito, M. Shuptar, A. Stolz, A. Taylor, B.P. Tousignant, A.D.F. Victory, D.R. Victory, J. Wei, E.M. Wellman, J.D. Wenstrom, Y. Yamazaki, C. Zhang, Q. Zhao, S. Zhao
    FRIB, East Lansing, Michigan, USA
  • K. Hosoyama
    KEK, Ibaraki, Japan
  • M.P. Kelly
    ANL, Lemont, Illinois, USA
  • R.E. Laxdal
    TRIUMF, Vancouver, Canada
  • M. Wiseman
    JLab, Newport News, Virginia, USA
  
  Funding: This work is supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661.
The Facility for Rare Isotope Beams (FRIB) is an ac-celerator-based facility funded by the US Department of Energy for nuclear physics research. FRIB is nearing the end of technical construction, with first user beams ex-pected in Summer 2022. Key features are the delivery of a variety of rare isotopes with a beam energy of ’ 200 MeV/u and a beam power of up to 400 kW. The facility is upgradable to 400 MeV/u and multi-user capability. The FRIB driver linac consists of 324 superconducting resonators and 69 superconducting solenoids in 46 cry-omodules. FRIB is the first linac to deploy a large number of HWRs (220) and the first heavy ion linac to operate at 2 K. We report on the completion of production and in-stallation of the FRIB cryomodules and phased beam commissioning results. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOOFAV10  
About • Received ※ 12 August 2021 — Revised ※ 16 August 2021 — Accepted ※ 21 August 2021 — Issue date ※ 04 May 2022
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MOPTEV002 Extended Range SRF Cavity Tuner for LCLS II HE Project cavity, SRF, operation, linac 203
 
  • Y.M. Pischalnikov, T.T. Arkan, C.J. Grimm, B.D. Hartsell, J.A. Kaluzny, T.N. Khabiboulline, Y.M. Orlov, J.C. Yun
    Fermilab, Batavia, Illinois, USA
  • C. Contreras-Martinez
    FRIB, East Lansing, Michigan, USA
  
  Funding: This manuscript has been authorized by Fermi Research Alliance LLC under Contract N. DE-AC02-07CH11359 with U.S. Department of Energy.
The off-frequency detune method is being considered to be applied in the LCLS-II-HE superconducting linac to produce multi-energy electron beams for supporting multiple undulator lines simultaneously. To deliver off-frequency operation (OFO) requirements for SRF cavity tuner must be changed. Tuner design modifications and results of the testing eight cavity/tuner system, deployed in verification cryomodule (vCM), will be presented. 		 
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DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPTEV002  
About • Received ※ 22 June 2021 — Revised ※ 16 July 2021 — Accepted ※ 19 August 2021 — Issue date ※ 23 September 2021
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MOPTEV017 Development and Operation of PIP-II Injector Test, SSR1 Cryomodule, 325 MHz Amplifiers cavity, rf-amplifier, operation, radio-frequency 245
 
  • J. Steimel, V.M. Grzelak, D.W. Peterson
    Fermilab, Batavia, Illinois, USA
  • V.R. Bala, S.K. Bharade, G. Joshi, R. Keshwani, J.K. Mishra, M.M. Pande, S. Shrotriya, H. Shukla, S. Singh, C.I. Sujo
    BARC, Mumbai, India
  • D. Balakrishna, N. Chikte, S. Dubey, C. G, V. Gollapalli, J. K Chandra, V. Kumar, M. M, A. Maheshwari, S.N. Nagaratnam, G. Poornima, T.V.S. Thalluri
    ECIL, Hyderabad, India
  
  Funding: 1Fermilab, U.S.Department of Energy 2 Bhabha Atomic Research Centre, Department of Atomic Energy, Government of India 3 Electronic Corporation of India, Department of Atomic Energy, Government of India
The PIP-II Injector Test (PIP2IT) has successfully accelerated ionized hydrogen up to 17MeV through a superconducting, single spoke resonator (SSR1) cryomodule at Fermi National Accelerator Laboratory (FNAL). Each of the SSR1 cavities is tuned to 325MHz and requires up to 6 kW of RF power to accelerate 2mA of ionized hydrogen at the design gradients. RF power amplifiers, specialized for SRF cavity beam operations, were designed by Bhabha Atomic Research Center (BARC) and constructed in a collaboration between the BARC in Mumbai, India and the Electronics Corporation of India Limited (ECIL) in Hyderabad, India. The RF amplifiers meet the specifications and requirements mutually approved between BARC and FNAL. They operate at 325 MHz with a linear power output of 7 kW in both CW and pulse mode. The amplifiers are compatible with the FNAL accelerator personnel safety system and the cavity protection interlocks. Access to controls and internal diagnostic instrumentation are compatible with EPICS control standards. This paper gives details about RF power amplifier development within the Department of Atomic Energy (DAE), India and the operational details with PIP2IT at FNAL. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPTEV017  
About • Received ※ 28 June 2021 — Revised ※ 08 September 2021 — Accepted ※ 18 November 2021 — Issue date ※ 14 May 2022
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MOPCAV001 Cavity Production and Testing of the First C75 Cryomodule for CEBAF cavity, GUI, operation, HOM 250
 
  • G. Ciovati, G. Cheng, E. Daly, G.K. Davis, M.A. Drury, J.F. Fischer, D. Forehand, K. Macha, F. Marhauser, E.A. McEwen, A.L.A. Mitchell, A.V. Reilly, R.A. Rimmer, S. Wang
    JLab, Newport News, Virginia, USA
  
  Funding: U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177.
The CEBAF cryomodule rework program was updated over the last few years to increase the energy gain of refurbished cryomodules to 75 MeV. The concept recycles the waveguide end-groups from original CEBAF cavities fabricated in the 1990s and replaces the five elliptical cells in each with a new optimized cell shape fabricated from large-grain, ingot Nb material. Eight cavities were fabricated at Research Instruments, Germany, and two cavities were built at Jefferson Lab. Each cavity was processed by electropolishing and tested at 2.07 K. The best eight cavities were assembled into ’cavity pairs’ and re-tested at 2.07 K, before assembly into the cryomodule. All but one cavity in the cryomodule were within 10% of the target accelerating gradient of 19 MV/m with a quality factor of 8·109. The performance limitations were field emission and multipacting. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPCAV001  
About • Received ※ 17 June 2021 — Accepted ※ 21 February 2022 — Issue date ※ 10 April 2022  
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MOPCAV002 Shape Evolution of C75 Large-Grain Niobium Half-Cells During Cavity Fabrication cavity, laser, FEM, software 255
 
  • G. Ciovati
    JLab, Newport News, Virginia, USA
  
  Funding: U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177.
The largely anisotropic deformation of large-grain Nb discs during deep drawing into half-cells poses a challenge for achieving a desired shape accuracy. Two 5-cell cavities for the C75 CEBAF cryomodule rework program have been fabricated at Jefferson Lab from large-grain Nb discs directly sliced from an ingot. The shape of the inner surface of eight half-cells has been inspected using a FARO Edge laser scanner during the fabrication process and compared to the reference shape. On average, approximately 63% of the half-cell inner surface was found to be within 0.1 mm of the reference shape and ~90% to be within 0.2 mm, after the final equator machining. Several 5-cell C75 cavities have also been fabricated at Research Instruments, Germany, and measurements of the shape accuracy using a Zeiss 3D coordinate measuring machine gave similar results. One half-cell was measured both at Research Instruments and Jefferson Lab for comparison. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPCAV002  
About • Received ※ 21 June 2021 — Accepted ※ 21 August 2021 — Issue date ※ 11 February 2022  
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MOPCAV005 Status of SNS Proton Power Upgrade SRF Cavities Production Qualification cavity, proton, site, neutron 265
 
  • P. Dhakal, E. Daly, G.K. Davis, J.F. Fischer, D. Forehand, N.A. Huque, A.L.A. Mitchell, P.D. Owen
    JLab, Newport News, Virginia, USA
  • M.P. Howell, S.-H. Kim, J.D. Mammosser
    ORNL, Oak Ridge, Tennessee, USA
  
  The Proton Power Upgrade project at Oak Ridge National Lab’s Spallation Neutron Source (SNS PPU) currently being constructed will double the proton beam power from 1.4 to 2.8 MW by adding 7 additional cryomodules, each contains four six-cell high beta (\beta = 0.81) superconducting radio frequency cavities. The cavities were built by Research Instruments, Germany, with all the cavity processing done at the vendor site, including electropolishing as the final active chemistry step. All 28 cavities needed for 7 cryomodules were delivered to Jefferson Lab, ready to be tested. The cryogenic RF qualifications and helium vessel welding were done at Jefferson Lab. The performance largely exceed the requirements, and greatly exceeded the performance of the original SNS cavity production series. Here, we present the summary of RF test on production cavities to this date.
This manuscript has been authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
 		 
poster icon Poster MOPCAV005 [1.065 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPCAV005  
About • Received ※ 19 June 2021 — Revised ※ 10 July 2021 — Accepted ※ 12 March 2022 — Issue date ※ 06 April 2022
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MOPCAV008 CiADS and HIAF Superconducting Cavity Development Status and the Transition to Production Stage cavity, linac, SRF, proton 273
 
  • M. Xu, H. Guo, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, C.L. Li, L.B. Liu, S.H. Liu, T. Liu, S.M. Shanab, T. Tan, Y. Tao, Y.Q. Wan, F.F. Wang, R.X. Wang, Z.J. Wang, P.R. Xiong, J.C. Yang, Z.Q. Yang, S.H. Zhang, S.X. Zhang
    IMP/CAS, Lanzhou, People’s Republic of China
  • E.Z. Zaplatin
    FZJ, Jülich, Germany
  
  Funding: Work supported by Large Research Infrastructures "China initiative Accelerator Driven System’(Grant No.2017-000052-75-01-000590 )
Two accelerators facilities, China initiative Accelerator Driven Sub-critical System (CiADS) and High Intensity heavy-ion Accelerator Facility (HIAF), co-funded by the China central and local government, is being designed and constructed at Huizhou city, Guangdong Province. The Institute of Modern Physics(IMP), Chinese Academy of Science is responded for constructing and operating the facility. CiADS’s mission is to demonstrate the principle and technical of employing high power protons to transit fission nuclear plant wastes. HIAF is defined as a nuclear structure research facility. The two linacs contains six types , totally 233 superconducting cavities, will be constructed in recent three years. Stable production rate and reliable surface processing will be the main challenges. This paper reports the cavity design, prototype status and massive production plan and status. 		 
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DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPCAV008  
About • Received ※ 22 June 2021 — Revised ※ 10 December 2021 — Accepted ※ 04 February 2022 — Issue date ※ 10 April 2022
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MOPCAV013 LCLS-II-HE Vertical Acceptance Testing Plans cavity, multipactoring, HOM, accelerating-gradient 291
 
  • J.T. Maniscalco, S. Aderhold, J.D. Fuerst, D. Gonnella
    SLAC, Menlo Park, California, USA
  • T.T. Arkan, M. Checchin, J.A. Kaluzny, S. Posen
    Fermilab, Batavia, Illinois, USA
  • J. Hogan, A.D. Palczewski, C.E. Reece, K.M. Wilson
    JLab, Newport News, Virginia, USA
  
  LCLS-II-HE has performance requirements similar to but generally more demanding than those of LCLS-II, with an operating gradient of 21 MV/m (up from 16 MV/m in LCLS-II) and tighter restrictions on field emission and multipacting. In this paper, we outline the requirements for the 1.3 GHz cavities and the plans for qualification of these cavities by vertical test. We discuss lessons learned from LCLS-II and highlight the changes implemented in the vertical test procedure for the new project.  
poster icon Poster MOPCAV013 [0.418 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPCAV013  
About • Received ※ 21 June 2021 — Revised ※ 12 July 2021 — Accepted ※ 21 August 2021 — Issue date ※ 02 May 2022
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TUPFAV003 Stable Beam Operation at 33 MV/m in STF-2 Cryomodules at KEK cavity, operation, accelerating-gradient, radiation 382
 
  • Y. Yamamoto, M. Akemoto, D.A. Arakawa, A. Araki, S. Araki, A. Aryshev, T. Dohmae, M. Egi, M.K. Fukuda, K. Hara, H. Hayano, Y. Honda, T. Honma, H. Ito, E. Kako, H. Katagiri, R. Katayama, M. Kawamura, N. Kimura, Y. Kojima, Y. Kondou, T. Konomi, M. Masuzawa, T. Matsumoto, S. Michizono, Y. Morikawa, H. Nakai, H. Nakajima, K. Nakanishi, M. Omet, T. Oyama, T. Saeki, H. Sakai, H. Shimizu, S.I. Takahara, R. Ueki, K. Umemori, A. Yamamoto
    KEK, Ibaraki, Japan
  • S. Aramoto
    Hiroshima University, Higashi-Hiroshima, Japan
  • M. Kuriki
    Hiroshima University, Graduate School of Science, Higashi-Hiroshima, Japan
  • Z.J. Liptak
    HU/AdSM, Higashi-Hiroshima, Japan
  • K. Sakaue
    The University of Tokyo, The School of Engineering, Tokyo, Japan
  • A. Yamamoto
    CERN, Meyrin, Switzerland
  
  In STF at KEK, as the operational demonstration of the SRF accelerator for ILC, the STF-2 cryomodules (CM1+CM2a: one and half size CM with 12 cavities) have achieved 33 MV/m as average accelerating gradient with 7 cavities in Mar/2019. After that, one cavity with the lowest performance installed in CM2a was replaced with one N-infused cavity developed for High-Q/High-G R&D between Japan and US. From this April, the beam operation started again and those CMs achieved 33 MV/m as average accelerating gradient with 9 cavities including one N-infused cavity again. This is the very important milestone for ILC. In this report, the detailed results will be presented.  
poster icon Poster TUPFAV003 [3.020 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPFAV003  
About • Received ※ 21 June 2021 — Revised ※ 11 July 2021 — Accepted ※ 21 August 2021 — Issue date ※ 01 November 2021
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TUPCAV005 Toward Qualifications of HB and LB 650 MHz Cavities for the Prototype Cryomodules for the PIP-II Project cavity, SRF, proton, status 448
 
  • M. Martinello, D.J. Bice, C. Boffo, S.K. Chandrasekaran, G.V. Eremeev, F. Furuta, T.N. Khabiboulline, K.E. McGee, A.V. Netepenko, J.P. Ozelis, A.I. Sukhanov, G. Wu
    Fermilab, Batavia, Illinois, USA
  • M. Bagre, V. Jain, A. Puntambekar, S. Raghvendra, P. Shrivastava
    RRCAT, Indore (M.P.), India
  • M. Bertucci, A. Bosotti, C. Pagani, R. Paparella
    INFN/LASA, Segrate (MI), Italy
  • P. Bhattacharyya, S. Ghosh, S. Ghosh, A. Mandal, S. Seth, S. Som
    VECC, Kolkata, India
  • M.P. Kelly, T. Reid
    ANL, Lemont, Illinois, USA
  • S.H. Kim, K.E. McGee, P.N. Ostroumov
    FRIB, East Lansing, Michigan, USA
  • K.K. Mistri, P.N. Prakash
    IUAC, New Delhi, India
  
  High-beta (HB) and low-beta (LB) 650 MHz cryomodules are key components of the Proton Improvement Plan II (PIP-II) project. In this contribution we present the results of several 5-cell HB650 cavities that have been processed and tested with the purpose of qualifying them for the prototype cryomodule assembly, which will take place later this year. We also present the first results obtained in LB650 single-cell cavities process optimization. Taking advantage of their very similar geometry, we are also analyzing the effect of different surface treatments in FRIB’s 5-cell medium-beta 644MHz cavities. Cavities processed with N-doping and mid-T baking showed very promising results in term of both Q-factors and accelerating gradient for these low-beta structures.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPCAV005  
About • Received ※ 01 July 2021 — Accepted ※ 02 November 2021 — Issue date ※ 16 May 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPCAV013 STC Qualification Tests of PIP-II HB650 Cavities cavity, vacuum, SRF, LLRF 465
 
  • A.I. Sukhanov, S.K. Chandrasekaran, G.V. Eremeev, F. Furuta, S. Kazakov, T.N. Khabiboulline, T.H. Nicol, Y.M. Pischalnikov, O.V. Prokofiev, V. Roger, G. Wu, V.P. Yakovlev, J.C. Yun
    Fermilab, Batavia, Illinois, USA
  • C. Contreras-Martinez
    FRIB, East Lansing, Michigan, USA
  
  Design of the high beta 650 MHz prototype cryomodule for PIP-II is currently undergoing at Fermilab. The cryomodule includes six 5-cell elliptical SRF cavities with accelerating voltage up to 20 MV and low heat dissipation (Q0 > 3.3 · 10zEhNZeHn). Characterization of performance of fully integrated jacketed cavities with high power coupler and tuner is crucial for the project. Such a characterization of jacketed cavity requires a horizontal test cryostat. The Fermilab Spoke Test Cryostat (STC) has been upgraded to accommodate testing of 650 MHz cavities. Commissioning of upgraded STC has been reported at SRF’19 conference. In this paper we present results of testing of the prototype HB650 cavity in upgraded STC facility. We characterize cavity performance and qualify it for the prototype HB650 cryomodule assembly.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPCAV013  
About • Received ※ 21 June 2021 — Accepted ※ 21 August 2021 — Issue date ※ 04 October 2021  
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TUPTEV004 In Situ Plasma Processing of Superconducting Cavities at Jefferson Lab cavity, plasma, HOM, software 485
 
  • T. Powers, N.C. Brock, T.D. Ganey
    JLab, Newport News, Virginia, USA
  
  Funding: Funding provided by SC Nuclear Physics Program through DOE SC Lab funding announcement Lab-20-2310
Jefferson Lab began a plasma processing program starting in the spring of 2019. Plasma processing is a common technique for removing hydrocarbons from surfaces, which increases the work function and reduces the secondary emission coefficient. Unlike helium processing which relies on ion bombardment of the field emitters, plasma processing uses free oxygen produced in the plasma to break down the hydrocarbons on the surface of the cavity. The residuals of the hydrocarbons in the form of water, carbon monoxide and carbon dioxide are removed from the cryomodule as part of the process gas flow. The initial focus of the effort is processing C100 cavities by injecting RF power into the HOM coupler ports. We will then start investigating processing of C50 cavities by introducing RF into the fundamental power coupler. The plan is to start processing cryomodules in the CEBAF tunnel in the mid-term future, with a goal of improving the operational gradients and the energy margin of the linacs. This work will describe the systems and methods used at JLAB for processing cavities using an argon oxygen gas mixture. Before and after plasma processing results will also be presented. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPTEV004  
About • Received ※ 21 June 2021 — Accepted ※ 05 October 2021 — Issue date ※ 02 May 2022  
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TUPTEV005 PIP-II 650 MHz Power Coupler Thermal Studies cavity, radiation, GUI, vacuum 490
 
  • H. Jenhani, S. Arsenyev
    CEA-IRFU, Gif-sur-Yvette, France
  • S. Kazakov, N. Solyak
    Fermilab, Batavia, Illinois, USA
  
  The Proton Improvement Plan - II (PIP-II) project is underway at Fermilab with an international collaboration involving CEA in the development and testing of 650 MHz cryomodules. One of the first main contributions of the CEA was the participation in the design efforts for the current 50 KW CW 650 MHz power couplers. This paper reports some of the results of thermal and paramet-ric studies carried out by the CEA on these power couplers  
poster icon Poster TUPTEV005 [0.806 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPTEV005  
About • Received ※ 21 June 2021 — Revised ※ 08 February 2022 — Accepted ※ 15 February 2022 — Issue date ※ 03 May 2022
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TUPTEV012 Progress and Preliminary Statistics for the ESS Series Spoke Cryomodule Test cavity, LLRF, SRF, controls 512
 
  • H. Li, K. Fransson, K.J. Gajewski, L. Hermansson, A. Miyazaki, R.J.M.Y. Ruber, R. Santiago Kern, M. Zhovner
    Uppsala University, Uppsala, Sweden
  
  The European spallation source (ESS), as a world-class high power proton accelerator facility, will be the first one to adopt 26 double spoke resonators (DSR) at its low energy section. As a new superconducting accelerating structure, these DSRs are therefore considered key technology and a challenge for the whole project. They will be the first DSRs in the world to be commissioned for a high power proton accelerator. Since 2019, FREIA Laboratory, Uppsala university, has successfully tested the first DSR prototype cryomodule and is now in charge of the acceptance tests of the ESS series cryomodules prior to installation in the tunnel. The cryomodule test, including cryogenic and RF testing, verifies operation of the cavities, couplers and cold tuning systems. This poster will present the test results for the ESS series spoke cryomodules, including preliminary statistics, experience in general.  
poster icon Poster TUPTEV012 [0.898 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPTEV012  
About • Received ※ 21 June 2021 — Revised ※ 18 December 2021 — Accepted ※ 06 May 2022 — Issue date ※ 06 May 2022
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TUPTEV016 Upgrade of the RHIC 56 MHz Superconducting Quarter-Wave Resonator Cryomodule cavity, coupling, operation, HOM 522
 
  • Z.A. Conway, R. Anderson, D. Holmes, K. Mernick, S. Polizzo, S.K. Seberg, F. Severino, K.S. Smith, Q. Wu, B.P. Xiao, W. Xu, A. Zaltsman
    BNL, Upton, New York, USA
  
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
In preparation for the 2023 RHIC sPHENIX experi-mental program the superconducting 56 MHz quarter-wave resonator cryomodule, used operationally for longitudinal bunch compression with up to 1 MV RF voltage, is being refit to accommodate an expected beam current of 418 mA per ring, an increase of ~1.5 relative to previous operation. The upgrades to the system include an improved fundamental mode damp-er, and dual function fundamental power and higher-order mode damper couplers. This paper will describe the preliminary testing, select subsystem changes and plans for testing the cryomodule prior to installation in the RHIC beam line in 2022. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPTEV016  
About • Received ※ 21 June 2021 — Revised ※ 09 February 2022 — Accepted ※ 22 February 2022 — Issue date ※ 28 April 2022
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TUPTEV017 Processing and Test Result of 650 MHz 50 kW CW Prototype Couplers for PIP-II Project vacuum, GUI, cavity, multipactoring 526
 
  • N. Solyak, B.M. Hanna, S. Kazakov
    Fermilab, Batavia, Illinois, USA
  
  For PIP-II project Fermilab is developing 650 MHz couplers to deliver up to 50 kW CW RF power to the superconducting low-beta (LB650) and high-beta (HB650) cavities. To meet project requirements two different designs of the couplers were proposed, one is conventional design with copper plated stainless steel walls. In second design (EM-shielded) a copper screen is used to shield stainless steel wall from electromagnetic field. For prototyping we built two couplers of each type and tested them at 50kW with full reflection at different reflection phases. In each test the assembly of two couplers were processed with DC bias up to +5 kV, starting with short pulses and ramping power up to 100 kW. Final run for 2 hours in CW mode at 50 kW to reach equilibrium temperature regime and qualify couplers. One pair of couplers was also processed without DC bias. Finally, all four couplers demonstrated full requirements and were qualified. Based on test results the conventional coupler with some modification was chosen as a baseline design. Modified version of coupler is now ordered for prototype of HB650 cryomodule. In paper we will discuss details of coupler processing and results  
poster icon Poster TUPTEV017 [2.211 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPTEV017  
About • Received ※ 21 June 2021 — Revised ※ 06 August 2021 — Accepted ※ 19 November 2021 — Issue date ※ 08 December 2021
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TUPTEV018 Status of RF Power Coupler for HWR in RISP cavity, simulation, vacuum, status 531
 
  • S. Lee, M. Lee, Y.U. Sohn
    IBS, Daejeon, Republic of Korea
  • Y.U. Sohn
    PAL, Pohang, Republic of Korea
  
  Funding: This work was supported by the Rare Isotope Science Project of Institute for Basic Science funded by Ministry of Science and ICT and NRF of Korea 2013M7A1A1075764.
A heavy-ion accelerator facility is under construction for Rare Isotope Science Project(RISP) in Korea. Four types of super conducting cavities, QWR, HWR, SSR1, and SSR2 are developed to accelerate the ion beams. The QWR cryomodule is already installed in the tunnel. The HWR cryomodule is transport to the tunnel. Here, the status of HWR RF power coupler is presented. After the fabrication, the coupler is test with high power RF. The some of the test results are described. 		 
poster icon Poster TUPTEV018 [1.740 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPTEV018  
About • Received ※ 21 June 2021 — Revised ※ 09 August 2021 — Accepted ※ 21 August 2021 — Issue date ※ 29 April 2022
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WEPFAV001 Cryomodule Development for the Materials Irradiation Facility: From IFMIF-EVEDA to IFMIF-DONES cavity, vacuum, linac, solenoid 534
 
  • N. Bazin, S. Chel
    CEA-DRF-IRFU, France
  
  For several years, CEA has been involved in the development of superconducting linac for fusion related project, with the goal to develop an high flux neutrons source to test and qualify specific materials to be used in fusion power plants. In the framework of the ITER Broder Approch, a prototype cryomodule is under construction in Japan for the IFMIF/EVEDA phase(Engineering Validation and Engineering Design Activities) and the construction of the Accelerator Prototype (LIPAc) at Rokkasho, fully representative of the IFMIF low energy (9 MeV) accelerator (125 mA of D+beam in continuous wave). Meanwhile, the design studies of a plant called DONES (Demo Oriented NEutron Source, derived from IFMIF) started, with a superconducting linac made of 5 cryomodules. These one are based on the same principles as the one developed for IFMIF/EVEDA, but taking into account the lessons learnt from the prototype. This paper will present the similarities but also the differences between the cryomodules for IFMIF/EVEDA and DONES.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPFAV001  
About • Received ※ 28 June 2021 — Revised ※ 23 August 2021 — Accepted ※ 23 August 2021 — Issue date ※ 13 October 2021
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WEPFAV004 Status of the Cryogenic Infrastructure for MESA cryogenics, experiment, SRF, operation 539
 
  • T. Stengler, K. Aulenbacher, F. Hug, D. Simon
    KPH, Mainz, Germany
  
  Funding: supported by the German Research Foundation (DFG): EXC 2118/2019
The Institute of Nuclear Physics at the Johannes Gutenberg University Mainz, Germany is currently constructing the Mainz Energy-recovering Superconducting Accelerator (MESA). The centerpiece of the MESA consists of two superconducting cryomodules of the ELBE/Rossendorf type, which are operated at 1.8 K. Furthermore, accelerator elements for polarimetry, a 10 T solenoid, and the external SRF test facility of the Helmholtz Institute Mainz have to be supplied with 4 K helium. One challenge here is to supply the components located throughout the accelerator according to their requirements and to establish a 16mbar system for 1.8 K operation. To ensure the required supply of helium at the different temperature levels, the existing helium liquefier has to be upgraded. The cryogenic infrastructure has to be adapted to the accelerator. The concept of the future cryogenic distribution network is presented in this paper and the design of the cryogenic facilities including the modifications is described in detail. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPFAV004  
About • Received ※ 21 June 2021 — Accepted ※ 21 August 2021 — Issue date ※ 10 April 2022  
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WEPFAV006 ILC Energy Upgrade Paths to 3 TeV cavity, linac, SRF, klystron 549
 
  • H. Padamsee
    Fermilab, Batavia, Illinois, USA
  
  We consider ILC upgrade paths beyond 1 TeV: (1) to 2 TeV and (2) to 3 TeV depending on the needs of high energy physics. Parameters for four scenarios will be presented and challenges discussed. 1. From 1 TeV to 2 TeV based on: a. Gradient advances of Nb cavities to 55 MV/m anticipated from on-going SRF R&D on Nb structures discussed in Section 4.3.x. b. Radically new travelling wave (TW) superconducting structures [1,2] optimized for effective gradients of 70+ MV/m, along with 100% increase in R/Q (discussed in more detail in Section 4.3.x). The large gain in R/Q has a major beneficial impact on the refrigerator heat load, the RF power, and the AC operating power. OR 2. From 1 TeV to 3 TeV based on a. Radically new travelling wave (TW) superconducting structures [1,2] optimized for effective gradients of 70+ MV/m, along with 100% increase in R/Q. The large gain in R/Q has a major beneficial impact on heat load, RF power, and the AC operating power. b. 80 MV/m gradient potential for Nb3Sn [3] with Q of 1x1010, based on extrapolations from high power pulsed measurements on single cell Nb3Sn cavities. Further, the operating temperature is 4.2 K instead of 2K.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPFAV006  
About • Received ※ 13 June 2021 — Accepted ※ 29 September 2021 — Issue date ※ 16 May 2022  
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WEPCAV012 Research and Development of 650 MHz Cavities for CEPC cavity, HOM, SRF, higher-order-mode 616
 
  • P. Sha, C. Dong, F.S. He, S. Jin, Z.Q. Li, B.Q. Liu, Z.H. Mi, W.M. Pan, J.Y. Zhai, X.Y. Zhang, H.J. Zheng
    IHEP, Beijing, People’s Republic of China
  
  Funding: This work was supported by the National Key Programme for S&T Research and Development (No. 2016YFA0400400), the Platform of Advanced Photon Source Technology R&D.
650 MHz 2-cell superconducting cavities are proposed for the main ring of the Circular Electron Positron Collider (CEPC). The design, fabrication, surface treatment (buffered chemical polishing) and vertical tests of the cavities with HOM couplers were conducted. The performance of the cavity at 2 K is not affected by the HOM coupler. The maximum intrinsic quality factor of the cavity with the HOM coupler reached 3.1·1010 at 20 MV/m. The vertical test results showed that the fundamental mode external quality factor of all HOM couplers is an order of magnitude larger than quality factor of the cavity. The HOM damping results for the 650 MHz 2-cell cavity were also measured at cryogenic temperature and compared with the simulated and measured results at room temperature. Two 650 MHz 2-cell cavities jacketed have been integrated into a test cryomodule for CEPC. Another 650 MHz 2-cell cavity reached 6·1010 at 22 MV/m after nitrogen infusion. In addition, two 650 MHz 1-cell cavities reached 2.7·1010 at 35 MV/m (fine grain) and 3.6·1010 at 32 MV/m (large grain) after electro-polishing, respectively. In future, electro-polishing will be applied to 650 MHz 2-cell cavity soon. 		 
poster icon Poster WEPCAV012 [1.961 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPCAV012  
About • Received ※ 21 June 2021 — Accepted ※ 07 December 2021 — Issue date ※ 02 May 2022  
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WEPCAV014 HOM Damper Design for BNL EIC 197 MHz Crab Cavity cavity, HOM, impedance, GUI 624
 
  • B.P. Xiao, Q. Wu
    BNL, Upton, New York, USA
  • S.U. De Silva, J.R. Delayen
    ODU, Norfolk, Virginia, USA
  • J.R. Delayen, R.A. Rimmer
    JLab, Newport News, Virginia, USA
  • Z. Li
    SLAC, Menlo Park, California, USA
  • S. Verdú-Andrés
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
  
  Funding: The work is supported by by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE.
The interaction region (IR) crab cavity system is a special RF system to compensate the loss of luminosity due to a 25 mrad crossing angle at the interaction point (IP) for BNL EIC. There will be six crab cavities, with four 197 MHz crab cavities and two 394 MHz crab cavities, installed on each side of the IP in the proton/ion ring, and one 394 MHz crab cavity on each side of the IP in the electron ring. Both rings share identical 394 MHz crab cavity design to minimize the cost and risk in designing a new RF system, and it will be scaled from 197 MHz crab cavity. In this paper, the HOM damper design for 197 MHz crab cavity is introduced. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPCAV014  
About • Received ※ 22 June 2021 — Revised ※ 17 October 2021 — Accepted ※ 17 December 2021 — Issue date ※ 07 April 2022
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WEPTEV011 Development of In-Situ Plasma Cleaning for the FRIB SRF Linac plasma, cavity, electron, operation 657
 
  • C. Zhang, W. Chang, K. Elliott, W. Hartung, S.H. Kim, J.T. Popielarski, K. Saito, T. Xu
    FRIB, East Lansing, Michigan, USA
  
  Development of techniques for in-situ plasma cleaning of quarter-wave and half-wave resonator cryomodules is underway at the Facility for Rare Isotope Beams (FRIB) at Michigan State University. If SRF cavity performance degradation is seen during future FRIB linac operation, in-situ plasma cleaning may help to restore performance without disassembly of the cavities from the cryomodules for off-line cleaning. A plasma cleaning feasibility study for FRIB cryomodules indicates that plasma cleaning can be done on-line without modifications to the RF couplers or cryomodules. Initial bench measurements have been performed on a FRIB half-wave resonator using noble gases (Ne, Ar), with and without added oxygen gas. The plasma ignition threshold has been measured as a function of gas pressure and composition. Studies of plasma cleaning efficacy are underway. Results will be presented.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPTEV011  
About • Received ※ 04 July 2021 — Revised ※ 08 November 2021 — Accepted ※ 24 December 2021 — Issue date ※ 01 March 2022
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WEPTEV013 New Frequency-Tuning System and Digital LLRF for Stable and Reliable Operation of SRILAC cavity, controls, linac, SRF 666
 
  • K. Suda, O. Kamigaito, K. Ozeki, N. Sakamoto, K. Yamada
    RIKEN Nishina Center, Wako, Japan
  • H. Hara, A. Miyamoto, K. Sennyu, T. Yanagisawa
    MHI-MS, Kobe, Japan
  • E. Kako, H. Nakai, H. Sakai, K. Umemori
    KEK, Ibaraki, Japan
  
  The superconducting booster linac at RIKEN (SRILAC) has ten 73-MHz quarter-wavelength resonators (QWRs) that are contained in three cryomodules. The beam commissioning of SRILAC was successfully performed in January 2020. Frequency tuning during cold operation is performed by compressing the beam port of the cavity with stainless wires and decreasing the length of each beam gap, similar to the method adopted at ANL and FRIB. However, each tuner is driven by a motor connected to gears, instead of using gas pressure. Since the intervals of the QWRs are small due to the beam dynamics, a compact design for the tuner was adopted. Each cavity was tuned to the design frequency, which required frequency changes of 3 kHz to 7 kHz depending on the cavity. Although no piezoelectric actuator is mounted on the tuning system, phase noise caused by microphonics can be sufficiently reduced by a phase-locked loop using a newly developed digital LLRF. The details of the tuning system as well as the digital LLRF will be presented.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPTEV013  
About • Received ※ 13 August 2021 — Revised ※ 13 September 2021 — Accepted ※ 11 November 2021 — Issue date ※ 22 November 2021
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WEPTEV015 Design of the 650 MHz High Beta Prototype Cryomodule for PIP-II at Fermilab cavity, vacuum, alignment, SRF 671
 
  • V. Roger, S.K. Chandrasekaran, S. Cheban, M. Chen, J. Helsper, J.P. Holzbauer, Y.M. Orlov, V. Poloubotko, B. Squires, N. Tanovic, G. Wu
    Fermilab, Batavia, Illinois, USA
  • N. Bazin, O. Napoly, C. Simon
    CEA-DRF-IRFU, France
  • R. Cubizolles, M. Lacroix
    CEA-IRFU, Gif-sur-Yvette, France
  • M.T.W. Kane
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • P. Khare
    RRCAT, Indore (M.P.), India
  
  Funding: This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics
The Proton Improvement Plan II (PIP-II) is the first U.S. accelerator project that will have significant contributions from international partners. The prototype High Beta 650 MHz cryomodule (pHB650 CM) is designed by an integrated design team, consisting of Fermilab (USA), CEA (France), UKRI-STFC (UK), and RRCAT (India). The manufacturing & assembly of this prototype cryomodule will be done at Fermilab, whereas the production cryomodules will be manufactured and/or assembled by UKRI-STFC, RRCAT, or Fermilab. Similar to the prototype Single Spoke Resonator 1 cryomodule (pSSR1 CM), this cryomodule is based on a strong-back at room temperature supporting the coldmass. The pSSR1 CM led to significant lessons being learnt on the design, procurement, and assembly processes. These lessons were incorporated into the design and processes for the pHB650 CM. Amongst many challenges faced, the main challenges of the pHB650 CM design were to make the cryomodule compatible to overseas transportation and to design components that can be procured in USA, Europe, and India. 		 
poster icon Poster WEPTEV015 [0.937 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPTEV015  
About • Received ※ 21 June 2021 — Revised ※ 28 February 2022 — Accepted ※ 20 April 2022 — Issue date ※ 16 May 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPTEV016 Field Emission Studies During ESS Cryomodule Tests at CEA Saclay cavity, electron, simulation, detector 677
 
  • E. Cenni
    CEA-IRFU, Gif-sur-Yvette, France
  • M. Baudrier, G. Devanz, L. Maurice, O. Piquet
    CEA-DRF-IRFU, France
  
  For the development of efficient superconducting cavi-ties, field emission is an important parasitic phenomena to monitor. A diagnostic system composed of Geiger-Mueller (G-M) probes, NaI(Tl) scintillators are placed in the cryomodule test stand. Collected data is analysed and confronted to particle tracking simulation and electro magnetic shower code. With such systematic analysis we aim to identify the most probable field emission location and hence help to improve clean procedures during as-sembly and operation.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPTEV016  
About • Received ※ 21 June 2021 — Revised ※ 22 September 2021 — Accepted ※ 18 December 2021 — Issue date ※ 17 May 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPTEV017 Transportation Analysis of the Fermilab High-Beta 650 MHz Cryomodule cavity, vacuum, acceleration, alignment 682
 
  • J. Helsper, S. Cheban
    Fermilab, Batavia, Illinois, USA
  • I. Salehinia
    Northern Illinois University, DeKalb, USA
  
  Funding: Work supported by Fermi Research Alliance, LLC under Contract No. DEAC02- 07CH11359 with the United States Department of Energy.
The prototype High-Beta 650 MHz cryomodule for the PIP-II project will be the first of its kind to be transported internationally, and the round trip from FNAL to STFC UKRI will use a combination of road and air transit. Transportation of an assembled cryomodule poses a significant technical challenge, as excitation can generate high stresses and cyclic loading. To accurately assess the behavior of the cryomodule, Finite Element Analysis (FEA) was used to analyze all major components. First, all individual components were studied. For the critical/complex components, the analysis was in fine detail. Afterwards, all models were brought to a simplified state (necessary for computational expenses), verified to have the same behavior as their detailed counterparts, and combined to form larger sub-assemblies, with the ultimate analysis including the full cryomodule. We report the criteria for acceptance and methods of analysis, and results for selected components and sub-assemblies. 		 
poster icon Poster WEPTEV017 [3.164 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPTEV017  
About • Received ※ 21 June 2021 — Revised ※ 27 December 2021 — Accepted ※ 01 March 2022 — Issue date ※ 02 May 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOCAV06 SARAF-Phase 2 Low-Beta and High-Beta Superconducting Cavities Qualification cavity, linac, SRF, MMI 703
 
  • G. Ferrand, G. Jullien, S. Ladegaillerie, N. Misiara, N. Pichoff, C. Servouin
    CEA-IRFU, Gif-sur-Yvette, France
  • M. Baudrier, E. Fayette, L. Maurice
    CEA-DRF-IRFU, France
  • A. Navitski, L. Zweibäumer
    RI Research Instruments GmbH, Bergisch Gladbach, Germany
  
  CEA is committed to delivering a Medium Energy Beam Transfer line and a superconducting linac (SCL) for SARAF accelerator in order to accelerate 5 mA beam of either protons from 1.3 MeV to 35 MeV or deuterons from 2.6 MeV to 40 MeV. The SCL consists in four 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 low-beta prototypes was qualified in 2019. Low-beta series manufacturing is on-going. The high-beta prototype was first tested in 2019 but failed. A new prototype was tested in the end of 2020. This contribution will present the results of the tests for low- and high-beta SARAF cavities, series and prototypes.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEOCAV06  
About • Received ※ 21 June 2021 — Revised ※ 17 October 2021 — Accepted ※ 20 December 2021 — Issue date ※ 17 May 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPFAV002 Fabrication and Installation of Newly Designed Cryostats and Top Flanges for the Vertical Test of RISP cavity, SRF, cryogenics, vacuum 733
 
  • M.O. Hyun, M.S. Kim, Y. Kim, J. Lee, M. Lee, J.H. Shin
    IBS, Daejeon, Republic of Korea
  • D.W. Kim, S.R. Kim
    CVE, Suwon, Gyeonggi, Republic of Korea
  
  Funding: This paper was supported by the Rare Isotope Science Project (RISP), which is funded by the Ministry of Science and ICT (MSIT) and National Research Foundation (NRF) of the Republic of Korea.
Rare Isotope Science Project (RISP) in the Institute of Basic Science (IBS), South Korea, is now operating SRF test facility in Sindong, Daejeon. Sindong SRF test facility has three vertical test pits and three horizontal test bunkers, 900 W cryogenic system, RF power system, and radiation protection system. This paper explains about detail procedures of constructing cryostats and top flanges for the vertical test of RISP, Installed cryostats and top flanges have insulation vacuum layer, magnetic and thermal shield, 4K/2K reservoir, heat exchanger, cryogenic valves for supplying liquid helium, vacuum lines, and electrical instrumentations for the superconducting cavity tests. 		 
poster icon Poster THPFAV002 [2.015 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPFAV002  
About • Received ※ 22 June 2021 — Revised ※ 21 August 2021 — Accepted ※ 23 October 2021 — Issue date ※ 22 November 2021
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THPFAV004 Solenoid Automatic Turn-On and Degaussing for FRIB Cryomodules solenoid, controls, MMI, status 737
 
  • W. Chang, Y. Choi, J.T. Popielarski, K. Saito, T. Xu, C. Zhang
    FRIB, East Lansing, Michigan, USA
  
  The superconducting driver linac for the Facility for Rare Isotope Beams (FRIB) will accelerate heavy ions to 200 MeV per nucleon. The linac includes 46 SRF cryomodules, with a total of 69 solenoid packages for beam focusing and steering. For efficient beam commissioning and future operation, all of the solenoids must be turned on and reach a stable operating condition in a short time. Additionally, when a warm-up of the cryomodules is needed, degaussing of the solenoid packages is needed to minimize the residual magnetic field in the SRF cavities. An automatic turn-on and degaussing program had been implemented for FRIB cryomodules to meet these requirements. This paper will describe the design, development, and implementation of the automated solenoid control program.  
poster icon Poster THPFAV004 [1.863 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPFAV004  
About • Received ※ 21 June 2021 — Revised ※ 19 September 2021 — Accepted ※ 15 December 2021 — Issue date ※ 01 March 2022
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THPFAV005 LCSL-II Cryomodule Testing at Fermilab cavity, LLRF, EPICS, operation 741
 
  • E.R. Harms, B.E. Chase, E. Cullerton, B.D. Hartsell, J. Hurd, M.J. Kucera, F.L. Lewis, A. Lunin, J.N. Makara, D.L. Newhart, D.J. Nicklaus, P.S. Prieto, J. Reid, R.P. Stanek, R. Wang
    Fermilab, Batavia, Illinois, USA
  • A.L. Benwell
    SLAC, Menlo Park, California, USA
  • C. Contreras-Martinez
    FRIB, East Lansing, Michigan, USA
  • C.M. Ginsburg
    JLab, Newport News, Virginia, USA
  
  Funding: This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics.
Cold powered testing of all LCLS-II production cryomodules at Fermilab is complete as of February 2021. A total of twenty-five tests on both 1.3 GHz and 3.9 GHz cryomodules were conducted over a nearly five year time span beginning in the summer of 2016. During the course of this campaign cutting-edge results for cavity Q0 and gradient in continuous wave operation were achieved. A summary of all test results will be presented, with a comparison to established acceptance criteria, as well as overall test stand statistics and lessons learned. 		 
poster icon Poster THPFAV005 [1.383 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPFAV005  
About • Received ※ 22 June 2021 — Revised ※ 24 November 2021 — Accepted ※ 05 January 2022 — Issue date ※ 01 March 2022
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THPFAV006 Degradation and Recovery of the LHC RF Cryomodule Performance Using the Helium Processing Technique cavity, vacuum, radiation, operation 746
 
  • K. Turaj, O. Brunner, A.C. Butterworth, F. Gerigk, P. Maesen, E. Montesinos, F. Peauger, M. Therasse, W. Venturini Delsolaro
    CERN, Meyrin, Switzerland
  
  The LHC RF cryomodule "Asia" suffered an accidental influx of about 0.5 l of tunnel air during the leak checks of the pumping manifolds. The resulting risk of particle contamination was difficult to assess, and could not be excluded with certainty. If one or more cavities were contaminated, a severe impact on beam operations in the LHC machine was to be expected. In order to minimize the risks, the Asia cryomodule has been replaced with a spare unit. Subsequently, the cryomodule was tested in the SM18 test facility without intermediate venting, and showed high levels of radiation due to field emission above 1.8 MV in one of the cavities. The other cavities were less strongly affected, but clear signs of contamination were observed. The helium processing technique was used to improve the performance of the SRF cavity with respect to field emission. This paper will discuss the results of the above-mentioned test.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPFAV006  
About • Received ※ 21 June 2021 — Revised ※ 14 January 2022 — Accepted ※ 27 April 2022 — Issue date ※ 01 May 2022
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THPFDV005 Superconducting RF Performance of Cornell 500 MHz N-Doped B-Cell SRF Cavitiy cavity, SRF, vacuum, GUI 764
 
  • M. Ge, T. Gruber, A.T. Holic, M. Liepe, J. Sears
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  
  The Cornell SRF group is working on rebuilding a 500 MHz B-cell cryomodule (CRYO-2 BB1-5) as a spared cryomodule for the operation of the CESR ring. To minimize BCS surface resistance, achieve a high quality-factor (Q0), and increase maximum fields, we prepared the cavity’s surface with electropolishing and performed a 2/6 N2-doping. In this work, we report 4.2 K and 2 K cavity test results with detailed surface resistance analysis, showing improved performance, including significant higher fields.  
poster icon Poster THPFDV005 [0.718 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPFDV005  
About • Received ※ 05 July 2021 — Revised ※ 10 August 2021 — Accepted ※ 21 August 2021 — Issue date ※ 22 April 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPFDV006 Seebeck Coefficient Measurement at Cryogenic Temperatures for the LCLS-II HE Project experiment, niobium, cryogenics, cavity 768
 
  • M. Ge, A.T. Holic, M. Liepe, J. Sears
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  
  Reducing thermoelectric currents during cooldown is important to maintain high-quality factors (Q0) of the cavities in the LCLS-II HE cryomodules. The temperature-dependent Seebeck coefficients of the materials used in the cryomodules are needed for quantitative estimations of thermoelectric currents. In this work, we present a setup for cryogenic Seebeck coefficient measurements as well as the measured Seebeck coefficients of high-pure niobium at cryogenic temperatures between 4K and 200K.  
poster icon Poster THPFDV006 [0.511 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPFDV006  
About • Received ※ 29 June 2021 — Revised ※ 10 August 2021 — Accepted ※ 21 August 2021 — Issue date ※ 26 November 2021
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPCAV002 Low Temperature Heat Treatment on the HWR Cavity cavity, controls, SRF, niobium 779
 
  • Y. Jung, H. Jang, H. Kim, H. Kim, J.W. Kim, M.S. Kim, J. Lee, M. Lee
    IBS, Daejeon, Republic of Korea
  • S. Jeon
    Kyungpook National University, Daegu, Republic of Korea
  
  Institute for Basic Science have been constructing Superconducting LINAC composed of quarter wave resonator (QWR) and half wave resonator (HWR). All QWR cavities have been completely fabricated and successfully tested to be assembled in QWR cryomodules. For now, we have been testing HWR cavities over 50%. For the testing period, the success rate experienced up and downs like we went through during the QWR tests. In many cases, we observed that some cavities did not reach requirement performance 2K although they showed high performance at 4K. We increased the temperature of heat treatment to cure the rapid Q drop at the high gradient and observed most cavities passed the test after heat treatment.  
poster icon Poster THPCAV002 [1.979 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPCAV002  
About • Received ※ 21 June 2021 — Revised ※ 25 August 2021 — Accepted ※ 22 November 2021 — Issue date ※ 23 February 2022
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THPCAV008 Results From the Proton Power Upgrade Project Cavity Quality Assurance Plan cavity, linac, hardware, niobium 801
 
  • J.D. Mammosser, B.E. Robertson
    ORNL RAD, Oak Ridge, Tennessee, USA
  • R. Afanador, M.S. Champion, M.N. Greenwood, M.P. Howell, S.-H. Kim, S.E. Stewart, D.J. Vandygriff
    ORNL, Oak Ridge, Tennessee, USA
  • A. Bitter, K.B. Bolz, A. Navitski, L. Zweibäumer
    RI Research Instruments GmbH, Bergisch Gladbach, Germany
  • E. Daly, G.K. Davis, P. Dhakal, D. Forehand, K. Macha, C.E. Reece, K.M. Wilson
    JLab, Newport News, Virginia, USA
  
  Funding: UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE)
The Proton Power Upgrade (PPU) Project at Oak Ridge National Lab’s Spallation Neutron Source (SNS) is currently under construction. The project will double the beam power from 1.4 to 2.8 MW. This is accomplished by increasing the beam current and adding seven new Superconducting Radio Frequency (SRF) cryomodules. Each new cryomodule will contain four six-cell, beta 0.81, PPU style cavities. A quality assurance plan was developed and implemented for the procurement of 32 PPU cavities. As part of this plan, reference cavities were qualified and sent to Research Instruments Co. for the development and verification of process steps. Here we present the results from this plan to date. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPCAV008  
About • Received ※ 04 June 2021 — Accepted ※ 06 September 2021 — Issue date ※ 16 May 2022  
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THPCAV009 Statistical Modeling of Peak Accelerating Gradients in LCLS-II and LCLS-II-HE cavity, multipactoring, simulation, accelerating-gradient 804
 
  • J.T. Maniscalco, S. Aderhold, J.D. Fuerst, D. Gonnella
    SLAC, Menlo Park, California, USA
  • T.T. Arkan, M. Checchin, J.A. Kaluzny, S. Posen
    Fermilab, Batavia, Illinois, USA
  • J. Hogan, A.D. Palczewski, C.E. Reece, K.M. Wilson
    JLab, Newport News, Virginia, USA
  
  In this report, we study the vertical test gradient performance and the gradient degradation between vertical test and cryomodule test for the 1.3 GHz LCLS-II cavities. We develop a model of peak gradient statistics, and use our understanding of the LCLS-II results and the changes implemented for LCLS-II-HE to estimate the expected gradient statistics for the new machine. Finally, we lay out a plan to ensure that the LCLS-II-HE cryomodule gradient specifications are met while minimizing cavity disqualification by introducing a variable acceptance threshold for the accelerating gradient.  
poster icon Poster THPCAV009 [1.311 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPCAV009  
About • Received ※ 21 June 2021 — Revised ※ 14 September 2021 — Accepted ※ 02 November 2021 — Issue date ※ 23 November 2021
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THPTEV001 FPC for RIKEN QWR vacuum, SRF, linac, Windows 825
 
  • K. Ozeki, O. Kamigaito, N. Sakamoto, K. Suda, K. Yamada
    RIKEN Nishina Center, Wako, Japan
  
  In RIKEN, three cryomodules which contain ten SC-QWRs in total (4 + 4 + 2) were constructed, and beam supply has been started since last year. The FPCs for RIKEN QWR have a disk-type single vacuum window at room-temperature region. A vacuum leakage occurred at one FPC, after 4th cool-down test. In addition, second vacuum leakage occurred at another FPC, after starting beam supply. A dew condensation at air side of vacuum window may degrade the brazing of vacuum window. In order to prevent a dew condensation and to restore damaged FPCs, an additional outer vacuum window using machinable ceramics was designed and attached to the FPCs. In this contribution, a structure of the FPC, troubles, provision for those troubles, and plan for reconstruction are reported.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV001  
About • Received ※ 22 June 2021 — Revised ※ 26 November 2021 — Accepted ※ 18 January 2022 — Issue date ※ 12 May 2022
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THPTEV002 Enhanced Pneumatic Tuner Control for FRIB Half-Wave Resonators controls, cavity, solenoid, feedback 829
 
  • W. Chang, W. Hartung, S.H. Kim, J.T. Popielarski, T. Xu, C. Zhang, S. Zhao
    FRIB, East Lansing, Michigan, USA
  
  The superconducting driver linac for the Facility for Rare Isotope Beams (FRIB) includes a total of 46 cryomodules; 31 cryomodules contain half-wave resonators (HWRs) with pneumatic tuners. Pneumatic tuner control is via solenoid valves connecting the tuner to a helium gas supply manifold and a gas return line. For precise compensation of cavity detuning over a small range, the control voltage for the solenoid valves must be calibrated. Some valves have hysteresis in the gas flow rate as a function of control voltage, such that their response may be nonlinear and not repeatable–this makes the control algorithm challenging. To improve the system performance, a new pneumatic tuner control system was developed which regulates the position of one stepper motor instead of the two solenoid valves.  
poster icon Poster THPTEV002 [1.325 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV002  
About • Received ※ 24 June 2021 — Revised ※ 15 December 2021 — Accepted ※ 17 February 2022 — Issue date ※ 16 May 2022
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THPTEV003 LCLS-II Cryomodules Production Experience and Lessons Learned Towards LCLS-II-HE Project cavity, controls, vacuum, SRF 832
 
  • T.T. Arkan, D.J. Bice, J.N. Blowers, C.J. Grimm, B.D. Hartsell, J.A. Kaluzny, M. Martinello, T.H. Nicol, Y.M. Orlov, S. Posen, K.S. Premo, R.P. Stanek
    Fermilab, Batavia, Illinois, USA
  
  Funding: DOE
LCLS-II is an upgrade project for the linear coherent light source (LCLS) at SLAC. The LCLS-II linac consists of thirty-five 1.3 GHz and two 3.9 GHz superconducting RF (SRF) continuous wave (CW) cryomodules with high quality factor cavities. Cryomodules were produced at Fermilab and at Jefferson Lab in collaboration with SLAC. Fermilab successfully completed the assembly, testing and delivery of seventeen 1.3 GHz and three 3.9 GHz cryomodules. LCLS-II-HE is a planned upgrade project to LCLS-II. The LCLS-II-HE linac will consist of twenty-three 1.3 GHz cryomodules with high gradient and high quality factor cavities. This paper presents LCLS-II-HE cryomodule production plans, emphasizing the improvements done based on the challenges, mitigations, and lessons learned from LCLS-II. 		 
poster icon Poster THPTEV003 [0.620 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV003  
About • Received ※ 21 June 2021 — Revised ※ 11 August 2021 — Accepted ※ 21 August 2021 — Issue date ※ 27 October 2021
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPTEV006 Design of the PIP-II 650 MHz Low Beta Cryomodule cavity, vacuum, SRF, superconductivity 841
 
  • N. Bazin, S. Berry, G. Maitre, O. Napoly, C. Simon
    CEA-DRF-IRFU, France
  • S. Bouaziz, R. Cubizolles, M. Lacroix
    CEA-IRFU, Gif-sur-Yvette, France
  • S.K. Chandrasekaran, Y.M. Orlov, V. Roger
    Fermilab, Batavia, Illinois, USA
  
  The Proton Improvement Plan II (PIP-II) that will be installed at Fermilab is the first U.S. accelerator project that will have significant contributions from international partners. CEA joined the international collaboration in 2018, and is responsible of the 650 MHz low-beta section made of 9 cryomodules, with the design of the cryostat (i.e the cryomodule without the cavities, the power couplers and the frequency tuning systems) and the manufacturing of its components, the assembly and tests of the pre-production cryomodule and the 9 series ones. This paper will present the design of the 650 MHz low-beta cryomodule.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV006  
About • Received ※ 02 July 2021 — Accepted ※ 30 January 2022 — Issue date ※ 01 May 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPTEV008 Development of a Digital LLRF System for SRF Cavities in RAON Accelerator cavity, controls, LLRF, SRF 845
 
  • H. Jang, D.H. Gil, Y. Jung, H. Kim, Y. Kim, M. Lee
    IBS, Daejeon, Republic of Korea
  
  An ion accelerator, RAON is planned and under construction in Daejeon, Korea by Rare Isotope Science Project (RISP) team in Institute of Basic Science (IBS). The purpose of this accelerator is the generation of rare isotope by ISOL (Isotope Separation On-Line) and IF (In-flight Fragmentation) method. To achieve this goal RAON adopted the superconducting cavities at three different frequency (81.25 MHz, 162.5 MHz and 325 MHz) and their RF field will be controlled independently for the acceleration of ions with various A/q. A solid state power amplifier and a low level RF (LLRF) controller pairs are under development to generate and to control the RF for the cavities. Recently the development and evaluation of the digital-based LLRF have been performed. For the operation and test of SRF cavities, self-excited loop (SEL) and generator-driven-resonator (GDR) algorithm is digitally implemented and its test was performed. In this paper the status and test result of RAON LLRF controller will be described.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV008  
About • Received ※ 21 June 2021 — Revised ※ 30 August 2021 — Accepted ※ 26 September 2021 — Issue date ※ 23 November 2021
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPTEV011 Experimental Validation of the Use of Cold Cathode Gauge inside the Cryomodule Insulation Vacuum vacuum, operation, experiment, linac 848
 
  • H. Jenhani, P. Carbonnier
    CEA-IRFU, Gif-sur-Yvette, France
  
  The Proton Improvement Plan - II (PIP-II) project is underway at Fermilab with an international collaboration involving CEA in the development and testing of 650 MHz cryomodules. The risk analysis related to cryomodule operation proposed to add a vacuum gauge on the power coupler to prevent the untimely rupture of its ceramic. Due to the advanced design of the cryomodules, the gauge needs to be integrated inside the insulation vacuum to reduce the impact of this new modification. The lack of experience feedback on a similar operating condition requires an experimental validation before the implementation. This article details the experimental tests carried out before the approval of this solution.  
poster icon Poster THPTEV011 [0.664 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV011  
About • Received ※ 21 June 2021 — Revised ※ 16 August 2021 — Accepted ※ 23 November 2021 — Issue date ※ 15 January 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPTEV012 Substitution of Spring Clamps for Bolts on SRF Cavity Flanges to Minimize Particle Generation cavity, SRF, vacuum, niobium 853
 
  • G.H. Biallas
    Hyperboloid LLC, Yorktown, Virginia, USA
  • E. Daly, K. Macha, C.E. Reece
    JLab, Newport News, Virginia, USA
  
  Funding: Funding supplied by US Department of Energy SBIR Grant #DE-SC0019579
Hyperboloid LLC developed and successfully tested a System of High Force Spring Clamps to substitute, one for one, for bolts on the flanges of SRF Cavities. The Clamps are like exceptionally forceful binder clips. The System, that includes the Hydraulic Openers that apply the clamps, minimizes generation of particulates when sealing cavity flanges. Hyperboloid LLC used ANSYS to design the titanium clamps that generate the force to seal the hexagonal cross section, relatively hard aluminum gasket developed for TESLA and used at JLab and other accelerators. The System is developed to be suitable for use in SRF Clean Rooms. Results of particle counter readings during bolt and clamp installation and superfluid helium challenges to the sealed flanges are discussed. Results of a half-size clamp that could seal a soft aluminum gasket and the attempt to seal a gasket made of niobium are also discussed.
L. Monaco, P. Michelato, C. Pagani, N. Panzeri, Experimental and Theoretical Analysis of Tesla-like SFRF Cavity Flanges, INFN Milano- LASA, I-20090 Segrate (MI), Italy. Proc. EPAC 2006, Edinburgh, SC 		 
poster icon Poster THPTEV012 [1.404 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV012  
About • Received ※ 21 June 2021 — Revised ※ 16 December 2021 — Accepted ※ 28 April 2022 — Issue date ※ 01 May 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPTEV013 LCLS-II Cryomodule Production at JLab: Summary and Lessons cavity, operation, FEL, SRF 858
 
  • N.A. Huque, E. Daly, J.P. Preble, K.M. Wilson
    JLab, Newport News, Virginia, USA
  
  Cryomodules for the Linear Coherent Light Source II (LCLS-II) at SLAC National Accelerator Laboratory were jointly fabricated at Thomas Jefferson National Accelerator Facility (JLab) and Fermi National Accelerator Facility (FNAL). Procurements, cavity testing, cryomodule assembly, and cryomodule testing were carried out at the two labs. Twenty-one 1.3 GHz cryomodules were fabricated at JLab. The LCLS-II cryomodules are based on the design used in the European X-Ray Free Electron Laser (XFEL) but modified for continuous wave operation. The higher performance requirements lead to challenges in cavity processing, microphonics, magnetic hygiene and cryomodule transportation. This paper outlines the cryomodule production experience at JLab, as well as improvements to procedures and infrastructure to overcome the performance challenges of the LCLS-II design.  
poster icon Poster THPTEV013 [2.446 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV013  
About • Received ※ 21 June 2021 — Revised ※ 02 December 2021 — Accepted ※ 24 January 2022 — Issue date ※ 01 May 2022
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THPTEV014 Managing Procurements in the Time of Covid-19: SNS-PPU as a Case Study operation, site, status, HOM 863
 
  • K.M. Wilson, G. Cheng, E. Daly, N.A. Huque, T. Huratiak, M. Laney, K. Macha, D.J. Maddox, M. Marchlik, P.D. Owen, T. Peshehonoff, M. Torres, M. Wiseman
    JLab, Newport News, Virginia, USA
  
  Funding: Supported by the Dept of Energy, Office of Nuclear Physics under contract DE-AC05-06OR23177 (JSA); and by UT-B which manages Oak Ridge National Laboratory under contract DE-AC05-00OR22725.
In early 2020, COVID-19 swept across the world. The accelerator industry, like many others, was impacted by disease, delays, shortages, and new working conditions. All Thomas Jefferson National Accelerator Facility (JLab) employees were sent home in mid-March 2020, with many still working remotely now. At the time, JLab was working on the Proton Power Upgrade (PPU) to the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). Procurements had been placed and were being managed, parts were being received and inspected. This paper details the JLab procurement plan for the SNS PPU project, and the mitigations that were developed to continue to support this project smoothly under the limitations imposed by COVID-19. 		 
poster icon Poster THPTEV014 [1.081 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV014  
About • Received ※ 15 June 2021 — Revised ※ 30 November 2021 — Accepted ※ 21 January 2022 — Issue date ※ 01 May 2022
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THPTEV017 Status of the LCLS-II-HE Project at Jefferson Lab cavity, SRF, HOM, vacuum 876
 
  • K.M. Wilson, J. Hogan, M. Laney, A.D. Palczewski, C.E. Reece
    JLab, Newport News, Virginia, USA
  
  Funding: This work was supported by the U.S. Department of Energy Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177 (JSA); and for BES under contract DE’AC02’76SF00515 (SLAC).
The Linac Coherent Light Source II High Energy (LCLS-II-HE) upgrade at the SLAC National Accelerator Laboratory is being constructed in partnership with the Thomas Jefferson National Accelerator Facility (JLab) and the Fermi National Accelerator Laboratory (FNAL). The cryomodule production scope consists of the design, procurement, construction, and acceptance testing of 24 eight-cavity, 1.3 GHz cryomodules, as well as R&D activities necessary to develop the required technology. To achieve this, JLab and FNAL are also contributing to SLAC’s effort to develop the cavity recipe and production processes necessary to meet the LCLS-II-HE goal of 20.8 MV/m and average Q0 of 2.7·1010. This paper details the JLab scope, focusing on the project initiation phase, in particular technology development and prototyping, project development and planning, and implementation of lessons learned from LCLS-II. 		 
poster icon Poster THPTEV017 [1.536 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV017  
About • Received ※ 21 June 2021 — Revised ※ 12 August 2021 — Accepted ※ 02 March 2022 — Issue date ※ 01 May 2022
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