SRF2023 - Classification: SRF Technology / Cryomodules

Paper	Title	Page
WEPWB061	Pre-Installation Performance of the RHIC 56 MHz Superconducting System	718
	Z.A. Conway, R. Anderson, J.C. Brutus, K. Hernandez, D. Holmes, K. Mernick, G. Narayan, S. Polizzo, S.K. Seberg, F. Severino, M. Sowinski, R. Than, 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. Pre-installation test results for the RHIC 56 MHz superconducting RF system are presented here. The 56 MHz quarter-wave resonator achieved a stable accelerating potential of 1.1 MV with 13 W of RF loss at 4.5 K demonstrating its viability for increasing the luminosity of sPHENIX collisions. The new 120 kW travelling wave fundamental mode damper and dual 6 kW combined-function fundamental power couplers perform as expected at 3 kW but remain to be operated with the expected ~40 times greater power achievable with the RHIC sPHENIX beams.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB061
About •	Received ※ 15 June 2023 — Revised ※ 26 June 2023 — Accepted ※ 02 July 2023 — Issue date ※ 17 July 2023
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WEPWB063	Final Design of the LB650 Cryomodule for the PIP-II Linear Accelerator	721
	R. Cubizolles, S. Ladegaillerie, A. Moreau CEA-IRFU, Gif-sur-Yvette, France N. Bazin, S. Berry, J. Drant, P. Garin, A. Raut, C. Simon CEA-DRF-IRFU, France S.K. Chandrasekaran, O. Napoly, 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 its scope covers the supply of the 650 MHz low-beta cryomodule section, 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 9 production modules. An important milestone was reached in April 2023 with the Final Design Review. This paper presents the detailed design of the 650 MHz low-beta cryomodules.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB063
About •	Received ※ 21 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 04 July 2023 — Issue date ※ 20 July 2023
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WEPWB064	Performance Analysis from ESS Cryomodule Testing at CEA	727
	O. Piquet, C. Arcambal, Q. Bertrand, P. Bosland, E. Cenni, G. Devanz, T. Hamelin CEA-IRFU, Gif-sur-Yvette, France P. Sahuquet CEA-DRF-IRFU, France
	CEA Saclay is in charge of the production of 30 elliptical cavities cryomodule as part of the in Kind contribution to the ESS superconducting. The two medium and high beta prototypes and the three first of each type of the series cryomodules have been tested at CEA in slightly different conditions than at ESS (both in terms of cryogenic operation as well as RF conditions). The goal of these tests was to validate the assembly procedure before the delivery of the series to ESS where the final acceptance tests are performed. This paper summarizes the main results obtained during the tests at CEA with a particular attention to the field emission behaviour.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB064
About •	Received ※ 20 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 07 July 2023
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WEPWB066	Final Design of the Production SSR1 Cryomodule for PIP-II Project at Fermilab	736
	J. Bernardini, M. Chen, J. Helsper, M. Kramp, F.L. Lewis, T.H. Nicol, M. Parise, D. Passarelli, V. Roger, G.V. Romanov, B. Squires Fermilab, Batavia, Illinois, USA P. Neri University of Pisa, Pisa, Italy
	Funding: Work supported by Fermi Research Alliance, LLC under Contract No. DEAC02- 07CH11359 with the United States Department of Energy, Office of Science, Office of High Energy Physics. This contribution reports the design of the production Single Spoke Resonator Type 1 Cryomodule (SSR1 CM) for the PIP-II project at Fermilab. The innovative design is based on a structure, the strongback, which supports the coldmass from the bottom, stays at room temperature during operations, and can slide longitudinally with respect to the vacuum vessel. The Fermilab style cryomodule developed for the prototype Single Spoke Resonator Type 1 (pSSR1), the prototype High Beta 650 MHz (pHB650), and preproduction Single Spoke Resonator Type 2 (ppSSR2) cryomodules is the baseline of the present design. The focus of this contribution is on the results of calculations and finite element analyses performed to optimize the critical components of the cryomodule: vacuum vessel, strongback, thermal shield, and magnetic shield.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB066
About •	Received ※ 17 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 15 July 2023
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WEPWB067	HB650 Cryomodule Design: From Prototype to Production	741
	V. Roger, S.K. Chandrasekaran, C.J. Grimm, J.P. Holzbauer, O. Napoly, J.P. Ozelis, D. Passarelli Fermilab, Batavia, Illinois, 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. In early 2023 the assembly of the prototype HB650 cryomodule (pHB650 CM) was completed and cold tests started to evaluate its performance. The lessons learned from the design, assembly and preliminary cold tests of this cryomodule, and from the design of the SSR2 pre-production cryomodule played a fundamental role during the design optimization process of the production HB650 cryomodule (HB650 CM). Several workshops have been organized to share experiences and solve problems. This paper presents the main design changes from pHB650 to the HB650 production cryomodules and their impact on the heat loads.
	Poster WEPWB067 [2.178 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB067
About •	Received ※ 18 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 01 July 2023
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WEPWB068	Characterization of Additive Manufacturing Materials for String Assembly in Cleanroom	746
	J. Bernardini, M. Parise, D. Passarelli Fermilab, Batavia, Illinois, USA
	Funding: Work supported by Fermi Research Alliance, LLC under Contract No. DEAC02- 07CH11359 with the United States Department of Energy, Office of Science, Office of High Energy Physics. Beamline components, such as superconducting radio frequency cavities and focusing lenses, need to be assembled together in a string while in a cleanroom environment. The present contribution identifies and characterizes materials for additive manufacturing that can be used in a cleanroom. The well known advantages of additive manufacturing processes would highly benefit the design and development of tooling needed for the mechanical support and alignment of string components. Cleanliness, mechanical properties, and leak tightness of the chosen materials are the main focus of this contribution, which also paves the way for the integration of such materials in cryomodule assemblies. Results reported here were obtained in the framework of the PIP-II project at Fermilab.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB068
About •	Received ※ 17 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 04 July 2023
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WEPWB070	Test Shipment of the PIP-II 650 MHz Transport Frame Between FNAL to STFC-UKRI	750
	J.P. Holzbauer, S.K. Chandrasekaran, C.J. Grimm, J.P. Ozelis, R. Thiede, A.D. Wixson Fermilab, Batavia, Illinois, USA M.T.W. Kane STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Funding: Work supported by Fermi Research Alliance, LLC under Contract No. DEAC02- 07CH11359 with the United States Department of Energy The PIP-II Project will receive fully assembled cryomodules from CEA and STFC-UKRI as in-kind contributions. Damage to these cryomodules during transport is understood to be a significant risk to the project, so an extensive testing and validation program is in process to mitigate this risk. The centerpiece of this effort is the eventual shipment from FNAL to STFC-UKRI and back of a prototype HB650 cryomodule with cold testing before and after shipment to verify no functionality changes from shipment. Most recently, a test shipment to the UK and back using a cryomodule analog was completed using realistic logistics, handling, instrumentation, and planning. The process of executing this test shipment, lessons learned, and plan moving forward will be presented here.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB070
About •	Received ※ 18 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 17 July 2023
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WEPWB073	Prototype HB650 Cryomodule Heat Loads Simulations	755
	G. Coladonato University of Illinois at Chicago, Chicago, USA D. Passarelli, V. Roger Fermilab, Batavia, Illinois, 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. During the design stages of the PIP-II cryomodules, many analytical calculations and FEA have been performed on simpler geometry in order to estimate the heat loads and also to optimize the design. To better analyze the cryomodule cold tests, simulations have been performed with MATLAB to determine the temperature of the main components during cool down and to determine the heat loads of the cryomodule. These simulations have been applied to the High Beta 650 MHz prototype cryomodule design and compared to the cold tests performed on it.
	Poster WEPWB073 [1.981 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB073
About •	Received ※ 19 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 28 June 2023
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WEPWB075	Impact of Solenoid Induced Residual Magnetic Fields on the Prototype SSR1 CM Performance	760
	D. Passarelli, J. Bernardini, C. Boffo, S.K. Chandrasekaran, A.H. Hogberg, T.N. Khabiboulline, J.P. Ozelis, M. Parise, V. Roger, G.V. Romanov, A.I. Sukhanov, G. Wu, Y. Xie, V.P. Yakovlev Fermilab, Batavia, Illinois, 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. A prototype cryomodule containing eight Single Spoke Resonators type-1 (SSR1) operating at 325 MHz and four superconducting focusing lenses was successfully assembled, cold tested, and accelerated beam in the framework of the PIP-II project at Fermilab. The impact of induced residual magnetic fields from the solenoids on performance of cavities is presented in this contribution. In addition, design optimizations for the production cryomodules as a result of this impact are highlighted.
	Poster WEPWB075 [2.429 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB075
About •	Received ※ 26 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 11 July 2023
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WEPWB076	Low Particulates Nitrogen Purge and Backfill during Prototype HB650 Cryomodule String Assembly	765
	T.J. Ring, M.B. Quinlan, G. Wu Fermilab, Batavia, Illinois, 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. A low particulate vacuum and purging system was developed to support PIP-II cryomodule string assembly. The overpressure can be controlled at a precision of 1 mbar above the atmospheric pressure regardless of the cavity or string assembly air volume. The system minimized the risk of uncontrolled nitrogen flow during the string assembly. Design features will be presented.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB076
About •	Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 09 July 2023
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WEPWB082	Operational Experience with Turn-Key SRF Systems for Small Accelerators Like MESA	768
	T. Stengler, K. Aulenbacher, F. Hug, P.S. Plattner KPH, Mainz, Germany
	Funding: The work is funded by the German Research Foundation (DFG) under the Cluster of Excellence "PRISMA+" EXC 2118/2019 and the Federal Ministry of Education and Research (BMBF) through project 05H21UMRB1 New SRF-based accelerator development at sites without long-term experience in SRF development is a major challenge. Especially in-house development of cryomodules is an almost impossible obstacle to overcome for small projects. To minimize such obstacles, turn-key SRF systems provided by industry can be of great importance. For the multiturn ERL MESA, which is currently under construction at Johannes Gutenberg-Universität Mainz, two turnkey cryomodules have been purchased from industry and successfully tested. The specifications of a design gradient of 12.5 MV/m in CW operation with an unloaded Q of 1.25*10¹⁰ at 1.8 K had to be met. Since the design of the modules had to be modified for high current CW operation, a close cooperation with the manufacturer was of great importance. By purchasing such a turn-key SRF system, the MESA project successfully established the SRF accelerator technology at the site within six years. This was achieved through close monitoring of the manufacturing process and close cooperation with the manufacturer. An overview of the experience with the successful technology transfer of a complete turn-key SRF system for small accelerators will be given.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB082
About •	Received ※ 25 June 2023 — Revised ※ 29 June 2023 — Accepted ※ 30 June 2023 — Issue date ※ 03 August 2023
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WEPWB083	Basic Design and Consideration of Li-Vapor Contamination for A-FNS SRF	773
	T. Ebisawa, K. Hasegawa, A. Kasugai, M. Oyaidzu, S. Sato QST Rokkasho, Aomori, Japan E. Kako, H. Sakai, K. Umemori KEK, Ibaraki, Japan
	The Advanced Fusion Neutron Source (A-FNS) project is in progressing in Japan, QST Rokkasho institute. A-FNS will demonstrate a performance of the DEMO DT fusion reactor material. In order to perform the test, a high intensity deuteron beam accelerator will be used to produce a high flux neutron field which is similar to the 14 MeV DT neutron. The Superconducting Radio-Frequency linear accelerator (SRF) is one component of the A-FNS accelerator system. Although the A-FNS accelerator system design is based on the IFMIF design, the improvement of some subsystem has been considering by taking into account the lessons learnt from the LIPAc project. In order to keep a high stability and availability of the SRF performance, we plan to increase the number of SRF cavities and cryomodules considering the trouble or degradation of the cavity performance and modify the engineering design of some components. In addition, changing of the beam transport line design and Li vapor contamination study of SRF cavity are conducting. In this presentation, the progress of the SRF design and related activities for A-FNS in QST will be presented.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB083
About •	Received ※ 28 June 2023 — Revised ※ 29 June 2023 — Accepted ※ 30 June 2023 — Issue date ※ 17 August 2023
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WEPWB085	Degradation and Recovery of Cavity Performance in SRILAC Cryomodules at RIBF	784
	N. Sakamoto, O. Kamigaito, K. Ozeki, K. Suda, K. Yamada RIKEN Nishina Center, Wako, Japan
	The RIKEN superconducting (SC) heavy-ion linear accelerator (SRILAC) has been providing beam supply for super-heavy elements synthesis experiments since its commissioning in January 2020. However, the long-term operation of SC radio-frequency (RF) cavities leads an increase in the X-ray levels caused by field emissions resulting from changes in the inner surface conditions. More than half of the ten SC 1/4 wavelength resonators (SC-QWRs) of SRILAC, operating at a frequency of 73 MHz, have experienced an increase in X-ray levels, thus, requiring adjustments to the acceleration voltage for continuous operation. While several conditioning methods have been employed for SC cavities, a fully established technique is yet to be determined. To address this situation, a relatively simple conditioning method was implemented at RIKEN. The proposed method uses high-voltage pulsed power and imposes a low load on the cavities.
	Poster WEPWB085 [12.789 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB085
About •	Received ※ 13 June 2023 — Revised ※ 26 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 01 July 2023
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WEPWB087	Copper Plating Qualification Process for the Fundamental Power Coupler Waveguides for CEBAF Cryomodules	790
	L. Zhao, G. Cheng, G. Ciovati, K.M. Wilson JLab, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC, supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177. To provide sufficient energy for CEBAF operation, cryomodules and components are being refurbished yearly as necessary. Copper plated fundamental power coupler waveguides are important components of the cryomodules. The integrity and quality of copper plating is critical to reduce the heat load from the waveguides into the He bath at 2.07 K. A search of copper plating resources is underway for plating or re-plating CEBAF-style waveguides. This effort ensures a continuous capability of copper plating on cryomodule components, especially on waveguides. To qualify plating vendors, the waveguide copper plating specifications were revisited, and a thorough plating evaluation process is being developed. The evaluation process ranges from coupon testing to sample waveguide qualification. Recent results are summarized and future work is planned.
	Poster WEPWB087 [1.582 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB087
About •	Received ※ 15 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 11 July 2023
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THIAA03	Completion of Testing Series Double-spoke Cavity Cryomodules for ESS	932
MOPMB097	use link to see paper's listing under its alternate paper code
	R. Santiago Kern, K. Fransson, K.J. Gajewski, L. Hermansson, H. Li, T. Lofnes, A. Miyazaki, M. Olvegård, I.P. Profatilova, R.J.M.Y. Ruber, C.D.I. Svanberg, M. Zhovner Uppsala University, Uppsala, Sweden
	The FREIA Laboratory at Uppsala University, Sweden, has completed the evaluation of 13 double-spoke cavity cryomodules for ESS. This is the first time double-spoke cavities will be deployed in a real machine. This paper summarizes testing procedures and statistics of the results and lessons learned.
	Slides THIAA03 [4.687 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-THIAA03
About •	Received ※ 16 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 29 June 2023
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THIXA05	Conduction-Cooled SRF Cavities: Opportunities and Challenges	973
	N.A. Stilin, H. Conklin, T. Gruber, A.T. Holic, M. Liepe, T.I. O’Connell, P. Quigley, J. Sears, V.D. Shemelin, J. Turco Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Thanks to improvements in the performance of both commercial cryocoolers and Nb₃Sn-coated superconducting radio-frequency (SRF) cavities, it is now possible to design and build compact, SRF cryomodules without the need for liquid cryogenics. In addition, these systems offer robust, non-expert, turn-key operation, making SRF technology significantly more accessible for smaller-scale applications in fields such as industry, national security, medicine, environmental sustainability, etc. To fully realize these systems, many technical and operational challenges must be overcome. These include properly cooling the SRF cavity via thermal conduction and designing high-power (~ 100 kW continuous) RF couplers which dissipate minimal heat (~ 1 W) at 4.2 K. This presentation will discuss these challenges and the solutions which have been developed at Cornell University and elsewhere.
	Slides THIXA05 [7.219 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-THIXA05
About •	Received ※ 27 June 2023 — Revised ※ 29 June 2023 — Accepted ※ 04 July 2023 — Issue date ※ 08 July 2023
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FRIBA01	SRF R&D for FRIB Linac Energy Upgrade with High-performance Medium-beta Elliptical Cavity CW Cryomodules
	S.H. Kim, W. Chang, K. Elliott, W. Hartung, K.E. McGee, E.S. Metzgar, P.N. Ostroumov, L. Popielarski, J. Rathke, T. Xu, S. Zhao FRIB, East Lansing, Michigan, USA D.J. Bice, C. Contreras-Martinez, G.V. Eremeev, Y.M. Pischalnikov Fermilab, Batavia, Illinois, USA B.M. Guilfoyle, M.P. Kelly, T. Reid ANL, Lemont, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy under Award Number DE-SC0000661. Further support provided by the US Department of Energy under Cooperative Agreement award number DE-SC0018362. Michigan State University is pursuing SRF R&D for FRIB400 upgrade, doubling the FRIB linac beam energy (400 MeV/u for the heaviest uranium beam) using ßopt=0.65 644 MHz 5-cell elliptical cavities. We have achieved unprecedented Q₀ in this cavity class, Q₀ = 3.5·10¹⁰ at E_acc of 17.5 MV/m in a nitrogen-doped bare niobium cavity in collaboration with FNAL and ANL. The next missions are achieving such high Q₀ in jacketed cavities and in cryomodules, achieving field-emission free performance at Epeak of 40 MV/m with reproducibility, developing a compact two-window high-power fundamental power coupler (15 kW CW), and achieving stable resonance control of cavities integrated with tuners in cryomodules. In this talk, we will present progress of the SRF R&D and discuss future plan.
	Slides FRIBA01 [2.513 MB]
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FRIBA02	Instrumentation for High Performance Cavities and Cryomodule Field Emission Analysis	978
	G. Devanz CEA-IRFU, Gif-sur-Yvette, France M. Baudrier, E. Cenni, L. Maurice, O. Piquet CEA-DRF-IRFU, France
	Field emission (FE) is one of the main reasons for the degradation of accelerator cryomodules, as field emitted current tends to become more severe during the beam operation. It is essential to better understand how this phenomenon is generated and evolves from the SRF cavity preparation in the clean room, through their assembly in the cryomodule until their final test and operation. Due to the shielding environment of a cavity in its vertical test stand, or the architecture of a cryomodule, the more faint radiation occurring at the FE onset remains undetected. More precise diagnostic and analysis tools are required to gain more information. We present the developpement of dedicated time-resolved detectors for the FE radiation which aim at improving its coverage in terms of solid angle and lower energy threshold sensitivity. We approach this topic through detailed simulation based on the Geant4 toolkit in order to analyse the interaction of FE radiation with the cavity environement and optimize the detectors with respect to their application in cryomodule or vertical test stands. We illustrate by analysing recent cryomodule experimental test data.
	Slides FRIBA02 [9.606 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-FRIBA02
About •	Received ※ 27 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 05 July 2023 — Issue date ※ 09 July 2023
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FRIBA05	Automation of FRIB SRF Cavities and SC Solenoids Turn-on/off	999
	W. Chang, Y. Choi, X.J. Du, W. Hartung, S.H. Kim, T. Konomi, S.R. Kunjir, H. Nguyen, K. Saito, T. Xu, S. Zhao FRIB, East Lansing, Michigan, USA A. Facco INFN/LNL, Legnaro (PD), Italy
	The superconducting driver Linac for the Facility for Rare Isotope Beams (FRIB) is a heavy ion accelerator that accelerate ions to 200 MeV per nucleon. The Linac has 46 cryomodules that contain 324 superconducting radio frequency (SRF) cavities and 69 superconducting (SC) solenoid packages. For operation of all cryomodules with high efficiency and reliability, automation for SRF cavity and SC solenoid fast turn-on/off is essentially. Based on cryomodule commissioning results and expert experience, all manual cavity and solenoid turn-on/off procedures and steps have been replaced by automatic programs for FRIB linac operation. This allows the operators to turn the systems on and off without expert-level training. Automation reduces the risk of human error, speeds up beam recovery after user access to experimental areas, and increases beam availability. The cavity turn-on procedure makes sure that the cavity can operate at low field with expected read backs, ramps up the field, and makes sure that the RF amplitude and phase are stable. The design, implementation, and operating experience with automation will be presented.
	Slides FRIBA05 [3.503 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-FRIBA05
About •	Received ※ 29 June 2023 — Revised ※ 16 August 2023 — Accepted ※ 21 August 2023 — Issue date ※ 21 August 2023
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FRIBA07	Status of the SLAC/MSU SRF Gun Development Project	1003
	S.J. Miller, Y. Al-Mahmoud, W. Chang, Y. Choi, C. Compton, X.J. Du, K. Elliott, W. Hartung, J.D. Hulbert, S.H. Kim, T. Konomi, D.G. Morris, M.S. Patil, L. Popielarski, K. Saito, A. Taylor, B.P. Tousignant, J. Wei, J.D. Wenstrom, K. Witgen, T. Xu FRIB, East Lansing, Michigan, USA C. Adolphsen, R. Coy, F. Ji, M.J. Murphy, J. Smedley, L. Xiao SLAC, Menlo Park, California, USA A. Arnold, S. Gatzmaga, P. Murcek, J. Teichert, R. Xiang HZDR, Dresden, Germany M.P. Kelly, T.B. Petersen, P. Piot ANL, Lemont, Illinois, USA J.W. Lewellen LANL, Los Alamos, New Mexico, USA
	Funding: Work supported by the Department of Energy under Contract DE-AC02-76SF00515 The Linac Coherent Light Source II High Energy (LCLS-II-HE) Project at SLAC includes the construction of a low-emittance injector (LEI) and a superconducting quarter-wave resonator (QWR) at 185.7 MHz. Several alternatives to a superconducting radio frequency (SRF) QWR gun were considered for the LEI, including nor-mal-conducting RF guns evolved from the LCLS-II gun design. Compared to normal-conducting designs, the combination of an intrinsically outstanding vacuum environment (for cathode lifetime), and the potential for a larger ultimate performance envelope, led to the deci-sion to pursue development of the QWR-SRF gun. A prototype gun is currently being designed and fabricated at the Facility for Rare Isotope Beams (FRIB) at Michi-gan State University (MSU). This paper presents perfor-mance goals for the new gun design, an overview of the prototype development effort, status, and future plans including fabrication.
	Slides FRIBA07 [9.655 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-FRIBA07
About •	Received ※ 15 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 11 July 2023
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Paper

Title

Page

Pre-Installation Performance of the RHIC 56 MHz Superconducting System

718

Z.A. Conway, R. Anderson, J.C. Brutus, K. Hernandez, D. Holmes, K. Mernick, G. Narayan, S. Polizzo, S.K. Seberg, F. Severino, M. Sowinski, R. Than, 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.
Pre-installation test results for the RHIC 56 MHz superconducting RF system are presented here. The 56 MHz quarter-wave resonator achieved a stable accelerating potential of 1.1 MV with 13 W of RF loss at 4.5 K demonstrating its viability for increasing the luminosity of sPHENIX collisions. The new 120 kW travelling wave fundamental mode damper and dual 6 kW combined-function fundamental power couplers perform as expected at 3 kW but remain to be operated with the expected ~40 times greater power achievable with the RHIC sPHENIX beams.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB061

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Received ※ 15 June 2023 — Revised ※ 26 June 2023 — Accepted ※ 02 July 2023 — Issue date ※ 17 July 2023

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WEPWB063

Final Design of the LB650 Cryomodule for the PIP-II Linear Accelerator

721

R. Cubizolles, S. Ladegaillerie, A. Moreau
CEA-IRFU, Gif-sur-Yvette, France
N. Bazin, S. Berry, J. Drant, P. Garin, A. Raut, C. Simon
CEA-DRF-IRFU, France
S.K. Chandrasekaran, O. Napoly, 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 its scope covers the supply of the 650 MHz low-beta cryomodule section, 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 9 production modules. An important milestone was reached in April 2023 with the Final Design Review. This paper presents the detailed design of the 650 MHz low-beta cryomodules.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB063

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Received ※ 21 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 04 July 2023 — Issue date ※ 20 July 2023

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WEPWB064

Performance Analysis from ESS Cryomodule Testing at CEA

727

O. Piquet, C. Arcambal, Q. Bertrand, P. Bosland, E. Cenni, G. Devanz, T. Hamelin
CEA-IRFU, Gif-sur-Yvette, France
P. Sahuquet
CEA-DRF-IRFU, France

CEA Saclay is in charge of the production of 30 elliptical cavities cryomodule as part of the in Kind contribution to the ESS superconducting. The two medium and high beta prototypes and the three first of each type of the series cryomodules have been tested at CEA in slightly different conditions than at ESS (both in terms of cryogenic operation as well as RF conditions). The goal of these tests was to validate the assembly procedure before the delivery of the series to ESS where the final acceptance tests are performed. This paper summarizes the main results obtained during the tests at CEA with a particular attention to the field emission behaviour.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB064

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Received ※ 20 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 07 July 2023

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WEPWB066

Final Design of the Production SSR1 Cryomodule for PIP-II Project at Fermilab

736

J. Bernardini, M. Chen, J. Helsper, M. Kramp, F.L. Lewis, T.H. Nicol, M. Parise, D. Passarelli, V. Roger, G.V. Romanov, B. Squires
Fermilab, Batavia, Illinois, USA
P. Neri
University of Pisa, Pisa, Italy

Funding: Work supported by Fermi Research Alliance, LLC under Contract No. DEAC02- 07CH11359 with the United States Department of Energy, Office of Science, Office of High Energy Physics.
This contribution reports the design of the production Single Spoke Resonator Type 1 Cryomodule (SSR1 CM) for the PIP-II project at Fermilab. The innovative design is based on a structure, the strongback, which supports the coldmass from the bottom, stays at room temperature during operations, and can slide longitudinally with respect to the vacuum vessel. The Fermilab style cryomodule developed for the prototype Single Spoke Resonator Type 1 (pSSR1), the prototype High Beta 650 MHz (pHB650), and preproduction Single Spoke Resonator Type 2 (ppSSR2) cryomodules is the baseline of the present design. The focus of this contribution is on the results of calculations and finite element analyses performed to optimize the critical components of the cryomodule: vacuum vessel, strongback, thermal shield, and magnetic shield.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB066

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Received ※ 17 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 15 July 2023

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WEPWB067

HB650 Cryomodule Design: From Prototype to Production

741

V. Roger, S.K. Chandrasekaran, C.J. Grimm, J.P. Holzbauer, O. Napoly, J.P. Ozelis, D. Passarelli
Fermilab, Batavia, Illinois, 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.
In early 2023 the assembly of the prototype HB650 cryomodule (pHB650 CM) was completed and cold tests started to evaluate its performance. The lessons learned from the design, assembly and preliminary cold tests of this cryomodule, and from the design of the SSR2 pre-production cryomodule played a fundamental role during the design optimization process of the production HB650 cryomodule (HB650 CM). Several workshops have been organized to share experiences and solve problems. This paper presents the main design changes from pHB650 to the HB650 production cryomodules and their impact on the heat loads.

Poster WEPWB067 [2.178 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB067

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Received ※ 18 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 01 July 2023

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WEPWB068

Characterization of Additive Manufacturing Materials for String Assembly in Cleanroom

746

J. Bernardini, M. Parise, D. Passarelli
Fermilab, Batavia, Illinois, USA

Funding: Work supported by Fermi Research Alliance, LLC under Contract No. DEAC02- 07CH11359 with the United States Department of Energy, Office of Science, Office of High Energy Physics.
Beamline components, such as superconducting radio frequency cavities and focusing lenses, need to be assembled together in a string while in a cleanroom environment. The present contribution identifies and characterizes materials for additive manufacturing that can be used in a cleanroom. The well known advantages of additive manufacturing processes would highly benefit the design and development of tooling needed for the mechanical support and alignment of string components. Cleanliness, mechanical properties, and leak tightness of the chosen materials are the main focus of this contribution, which also paves the way for the integration of such materials in cryomodule assemblies. Results reported here were obtained in the framework of the PIP-II project at Fermilab.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB068

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Received ※ 17 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 04 July 2023

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WEPWB070

Test Shipment of the PIP-II 650 MHz Transport Frame Between FNAL to STFC-UKRI

750

J.P. Holzbauer, S.K. Chandrasekaran, C.J. Grimm, J.P. Ozelis, R. Thiede, A.D. Wixson
Fermilab, Batavia, Illinois, USA
M.T.W. Kane
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Funding: Work supported by Fermi Research Alliance, LLC under Contract No. DEAC02- 07CH11359 with the United States Department of Energy
The PIP-II Project will receive fully assembled cryomodules from CEA and STFC-UKRI as in-kind contributions. Damage to these cryomodules during transport is understood to be a significant risk to the project, so an extensive testing and validation program is in process to mitigate this risk. The centerpiece of this effort is the eventual shipment from FNAL to STFC-UKRI and back of a prototype HB650 cryomodule with cold testing before and after shipment to verify no functionality changes from shipment. Most recently, a test shipment to the UK and back using a cryomodule analog was completed using realistic logistics, handling, instrumentation, and planning. The process of executing this test shipment, lessons learned, and plan moving forward will be presented here.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB070

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Received ※ 18 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 17 July 2023

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WEPWB073

Prototype HB650 Cryomodule Heat Loads Simulations

755

G. Coladonato
University of Illinois at Chicago, Chicago, USA
D. Passarelli, V. Roger
Fermilab, Batavia, Illinois, 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.
During the design stages of the PIP-II cryomodules, many analytical calculations and FEA have been performed on simpler geometry in order to estimate the heat loads and also to optimize the design. To better analyze the cryomodule cold tests, simulations have been performed with MATLAB to determine the temperature of the main components during cool down and to determine the heat loads of the cryomodule. These simulations have been applied to the High Beta 650 MHz prototype cryomodule design and compared to the cold tests performed on it.

Poster WEPWB073 [1.981 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB073

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Received ※ 19 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 28 June 2023

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WEPWB075

Impact of Solenoid Induced Residual Magnetic Fields on the Prototype SSR1 CM Performance

760

D. Passarelli, J. Bernardini, C. Boffo, S.K. Chandrasekaran, A.H. Hogberg, T.N. Khabiboulline, J.P. Ozelis, M. Parise, V. Roger, G.V. Romanov, A.I. Sukhanov, G. Wu, Y. Xie, V.P. Yakovlev
Fermilab, Batavia, Illinois, 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.
A prototype cryomodule containing eight Single Spoke Resonators type-1 (SSR1) operating at 325 MHz and four superconducting focusing lenses was successfully assembled, cold tested, and accelerated beam in the framework of the PIP-II project at Fermilab. The impact of induced residual magnetic fields from the solenoids on performance of cavities is presented in this contribution. In addition, design optimizations for the production cryomodules as a result of this impact are highlighted.

Poster WEPWB075 [2.429 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB075

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Received ※ 26 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 11 July 2023

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WEPWB076

Low Particulates Nitrogen Purge and Backfill during Prototype HB650 Cryomodule String Assembly

765

T.J. Ring, M.B. Quinlan, G. Wu
Fermilab, Batavia, Illinois, 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.
A low particulate vacuum and purging system was developed to support PIP-II cryomodule string assembly. The overpressure can be controlled at a precision of 1 mbar above the atmospheric pressure regardless of the cavity or string assembly air volume. The system minimized the risk of uncontrolled nitrogen flow during the string assembly. Design features will be presented.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB076

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Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 09 July 2023

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WEPWB082

Operational Experience with Turn-Key SRF Systems for Small Accelerators Like MESA

768

T. Stengler, K. Aulenbacher, F. Hug, P.S. Plattner
KPH, Mainz, Germany

Funding: The work is funded by the German Research Foundation (DFG) under the Cluster of Excellence "PRISMA+" EXC 2118/2019 and the Federal Ministry of Education and Research (BMBF) through project 05H21UMRB1
New SRF-based accelerator development at sites without long-term experience in SRF development is a major challenge. Especially in-house development of cryomodules is an almost impossible obstacle to overcome for small projects. To minimize such obstacles, turn-key SRF systems provided by industry can be of great importance. For the multiturn ERL MESA, which is currently under construction at Johannes Gutenberg-Universität Mainz, two turnkey cryomodules have been purchased from industry and successfully tested. The specifications of a design gradient of 12.5 MV/m in CW operation with an unloaded Q of 1.25*10¹⁰ at 1.8 K had to be met. Since the design of the modules had to be modified for high current CW operation, a close cooperation with the manufacturer was of great importance. By purchasing such a turn-key SRF system, the MESA project successfully established the SRF accelerator technology at the site within six years. This was achieved through close monitoring of the manufacturing process and close cooperation with the manufacturer. An overview of the experience with the successful technology transfer of a complete turn-key SRF system for small accelerators will be given.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB082

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Received ※ 25 June 2023 — Revised ※ 29 June 2023 — Accepted ※ 30 June 2023 — Issue date ※ 03 August 2023

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WEPWB083

Basic Design and Consideration of Li-Vapor Contamination for A-FNS SRF

773

T. Ebisawa, K. Hasegawa, A. Kasugai, M. Oyaidzu, S. Sato
QST Rokkasho, Aomori, Japan
E. Kako, H. Sakai, K. Umemori
KEK, Ibaraki, Japan

The Advanced Fusion Neutron Source (A-FNS) project is in progressing in Japan, QST Rokkasho institute. A-FNS will demonstrate a performance of the DEMO DT fusion reactor material. In order to perform the test, a high intensity deuteron beam accelerator will be used to produce a high flux neutron field which is similar to the 14 MeV DT neutron. The Superconducting Radio-Frequency linear accelerator (SRF) is one component of the A-FNS accelerator system. Although the A-FNS accelerator system design is based on the IFMIF design, the improvement of some subsystem has been considering by taking into account the lessons learnt from the LIPAc project. In order to keep a high stability and availability of the SRF performance, we plan to increase the number of SRF cavities and cryomodules considering the trouble or degradation of the cavity performance and modify the engineering design of some components. In addition, changing of the beam transport line design and Li vapor contamination study of SRF cavity are conducting. In this presentation, the progress of the SRF design and related activities for A-FNS in QST will be presented.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB083

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Received ※ 28 June 2023 — Revised ※ 29 June 2023 — Accepted ※ 30 June 2023 — Issue date ※ 17 August 2023

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WEPWB085

Degradation and Recovery of Cavity Performance in SRILAC Cryomodules at RIBF

784

N. Sakamoto, O. Kamigaito, K. Ozeki, K. Suda, K. Yamada
RIKEN Nishina Center, Wako, Japan

The RIKEN superconducting (SC) heavy-ion linear accelerator (SRILAC) has been providing beam supply for super-heavy elements synthesis experiments since its commissioning in January 2020. However, the long-term operation of SC radio-frequency (RF) cavities leads an increase in the X-ray levels caused by field emissions resulting from changes in the inner surface conditions. More than half of the ten SC 1/4 wavelength resonators (SC-QWRs) of SRILAC, operating at a frequency of 73 MHz, have experienced an increase in X-ray levels, thus, requiring adjustments to the acceleration voltage for continuous operation. While several conditioning methods have been employed for SC cavities, a fully established technique is yet to be determined. To address this situation, a relatively simple conditioning method was implemented at RIKEN. The proposed method uses high-voltage pulsed power and imposes a low load on the cavities.

Poster WEPWB085 [12.789 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB085

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Received ※ 13 June 2023 — Revised ※ 26 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 01 July 2023

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WEPWB087

Copper Plating Qualification Process for the Fundamental Power Coupler Waveguides for CEBAF Cryomodules

790

L. Zhao, G. Cheng, G. Ciovati, K.M. Wilson
JLab, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC, supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177.
To provide sufficient energy for CEBAF operation, cryomodules and components are being refurbished yearly as necessary. Copper plated fundamental power coupler waveguides are important components of the cryomodules. The integrity and quality of copper plating is critical to reduce the heat load from the waveguides into the He bath at 2.07 K. A search of copper plating resources is underway for plating or re-plating CEBAF-style waveguides. This effort ensures a continuous capability of copper plating on cryomodule components, especially on waveguides. To qualify plating vendors, the waveguide copper plating specifications were revisited, and a thorough plating evaluation process is being developed. The evaluation process ranges from coupon testing to sample waveguide qualification. Recent results are summarized and future work is planned.

Poster WEPWB087 [1.582 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB087

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Received ※ 15 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 11 July 2023

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THIAA03

Completion of Testing Series Double-spoke Cavity Cryomodules for ESS

932

MOPMB097

use link to see paper's listing under its alternate paper code

R. Santiago Kern, K. Fransson, K.J. Gajewski, L. Hermansson, H. Li, T. Lofnes, A. Miyazaki, M. Olvegård, I.P. Profatilova, R.J.M.Y. Ruber, C.D.I. Svanberg, M. Zhovner
Uppsala University, Uppsala, Sweden

The FREIA Laboratory at Uppsala University, Sweden, has completed the evaluation of 13 double-spoke cavity cryomodules for ESS. This is the first time double-spoke cavities will be deployed in a real machine. This paper summarizes testing procedures and statistics of the results and lessons learned.

Slides THIAA03 [4.687 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-THIAA03

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Received ※ 16 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 29 June 2023

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THIXA05

Conduction-Cooled SRF Cavities: Opportunities and Challenges

973

N.A. Stilin, H. Conklin, T. Gruber, A.T. Holic, M. Liepe, T.I. O’Connell, P. Quigley, J. Sears, V.D. Shemelin, J. Turco
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Thanks to improvements in the performance of both commercial cryocoolers and Nb₃Sn-coated superconducting radio-frequency (SRF) cavities, it is now possible to design and build compact, SRF cryomodules without the need for liquid cryogenics. In addition, these systems offer robust, non-expert, turn-key operation, making SRF technology significantly more accessible for smaller-scale applications in fields such as industry, national security, medicine, environmental sustainability, etc. To fully realize these systems, many technical and operational challenges must be overcome. These include properly cooling the SRF cavity via thermal conduction and designing high-power (~ 100 kW continuous) RF couplers which dissipate minimal heat (~ 1 W) at 4.2 K. This presentation will discuss these challenges and the solutions which have been developed at Cornell University and elsewhere.

Slides THIXA05 [7.219 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-THIXA05

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Received ※ 27 June 2023 — Revised ※ 29 June 2023 — Accepted ※ 04 July 2023 — Issue date ※ 08 July 2023

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FRIBA01

SRF R&D for FRIB Linac Energy Upgrade with High-performance Medium-beta Elliptical Cavity CW Cryomodules

S.H. Kim, W. Chang, K. Elliott, W. Hartung, K.E. McGee, E.S. Metzgar, P.N. Ostroumov, L. Popielarski, J. Rathke, T. Xu, S. Zhao
FRIB, East Lansing, Michigan, USA
D.J. Bice, C. Contreras-Martinez, G.V. Eremeev, Y.M. Pischalnikov
Fermilab, Batavia, Illinois, USA
B.M. Guilfoyle, M.P. Kelly, T. Reid
ANL, Lemont, Illinois, USA

Funding: Work supported by the U.S. Department of Energy under Award Number DE-SC0000661. Further support provided by the US Department of Energy under Cooperative Agreement award number DE-SC0018362.
Michigan State University is pursuing SRF R&D for FRIB400 upgrade, doubling the FRIB linac beam energy (400 MeV/u for the heaviest uranium beam) using ßopt=0.65 644 MHz 5-cell elliptical cavities. We have achieved unprecedented Q₀ in this cavity class, Q₀ = 3.5·10¹⁰ at E_acc of 17.5 MV/m in a nitrogen-doped bare niobium cavity in collaboration with FNAL and ANL. The next missions are achieving such high Q₀ in jacketed cavities and in cryomodules, achieving field-emission free performance at Epeak of 40 MV/m with reproducibility, developing a compact two-window high-power fundamental power coupler (15 kW CW), and achieving stable resonance control of cavities integrated with tuners in cryomodules. In this talk, we will present progress of the SRF R&D and discuss future plan.

Slides FRIBA01 [2.513 MB]

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FRIBA02

Instrumentation for High Performance Cavities and Cryomodule Field Emission Analysis

978

G. Devanz
CEA-IRFU, Gif-sur-Yvette, France
M. Baudrier, E. Cenni, L. Maurice, O. Piquet
CEA-DRF-IRFU, France

Field emission (FE) is one of the main reasons for the degradation of accelerator cryomodules, as field emitted current tends to become more severe during the beam operation. It is essential to better understand how this phenomenon is generated and evolves from the SRF cavity preparation in the clean room, through their assembly in the cryomodule until their final test and operation. Due to the shielding environment of a cavity in its vertical test stand, or the architecture of a cryomodule, the more faint radiation occurring at the FE onset remains undetected. More precise diagnostic and analysis tools are required to gain more information. We present the developpement of dedicated time-resolved detectors for the FE radiation which aim at improving its coverage in terms of solid angle and lower energy threshold sensitivity. We approach this topic through detailed simulation based on the Geant4 toolkit in order to analyse the interaction of FE radiation with the cavity environement and optimize the detectors with respect to their application in cryomodule or vertical test stands. We illustrate by analysing recent cryomodule experimental test data.

Slides FRIBA02 [9.606 MB]

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reference for this paper ※ doi:10.18429/JACoW-SRF2023-FRIBA02

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Received ※ 27 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 05 July 2023 — Issue date ※ 09 July 2023

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FRIBA05

Automation of FRIB SRF Cavities and SC Solenoids Turn-on/off

999

W. Chang, Y. Choi, X.J. Du, W. Hartung, S.H. Kim, T. Konomi, S.R. Kunjir, H. Nguyen, K. Saito, T. Xu, S. Zhao
FRIB, East Lansing, Michigan, USA
A. Facco
INFN/LNL, Legnaro (PD), Italy

The superconducting driver Linac for the Facility for Rare Isotope Beams (FRIB) is a heavy ion accelerator that accelerate ions to 200 MeV per nucleon. The Linac has 46 cryomodules that contain 324 superconducting radio frequency (SRF) cavities and 69 superconducting (SC) solenoid packages. For operation of all cryomodules with high efficiency and reliability, automation for SRF cavity and SC solenoid fast turn-on/off is essentially. Based on cryomodule commissioning results and expert experience, all manual cavity and solenoid turn-on/off procedures and steps have been replaced by automatic programs for FRIB linac operation. This allows the operators to turn the systems on and off without expert-level training. Automation reduces the risk of human error, speeds up beam recovery after user access to experimental areas, and increases beam availability. The cavity turn-on procedure makes sure that the cavity can operate at low field with expected read backs, ramps up the field, and makes sure that the RF amplitude and phase are stable. The design, implementation, and operating experience with automation will be presented.

Slides FRIBA05 [3.503 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-FRIBA05

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Received ※ 29 June 2023 — Revised ※ 16 August 2023 — Accepted ※ 21 August 2023 — Issue date ※ 21 August 2023

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FRIBA07

Status of the SLAC/MSU SRF Gun Development Project

1003

S.J. Miller, Y. Al-Mahmoud, W. Chang, Y. Choi, C. Compton, X.J. Du, K. Elliott, W. Hartung, J.D. Hulbert, S.H. Kim, T. Konomi, D.G. Morris, M.S. Patil, L. Popielarski, K. Saito, A. Taylor, B.P. Tousignant, J. Wei, J.D. Wenstrom, K. Witgen, T. Xu
FRIB, East Lansing, Michigan, USA
C. Adolphsen, R. Coy, F. Ji, M.J. Murphy, J. Smedley, L. Xiao
SLAC, Menlo Park, California, USA
A. Arnold, S. Gatzmaga, P. Murcek, J. Teichert, R. Xiang
HZDR, Dresden, Germany
M.P. Kelly, T.B. Petersen, P. Piot
ANL, Lemont, Illinois, USA
J.W. Lewellen
LANL, Los Alamos, New Mexico, USA

Funding: Work supported by the Department of Energy under Contract DE-AC02-76SF00515
The Linac Coherent Light Source II High Energy (LCLS-II-HE) Project at SLAC includes the construction of a low-emittance injector (LEI) and a superconducting quarter-wave resonator (QWR) at 185.7 MHz. Several alternatives to a superconducting radio frequency (SRF) QWR gun were considered for the LEI, including nor-mal-conducting RF guns evolved from the LCLS-II gun design. Compared to normal-conducting designs, the combination of an intrinsically outstanding vacuum environment (for cathode lifetime), and the potential for a larger ultimate performance envelope, led to the deci-sion to pursue development of the QWR-SRF gun. A prototype gun is currently being designed and fabricated at the Facility for Rare Isotope Beams (FRIB) at Michi-gan State University (MSU). This paper presents perfor-mance goals for the new gun design, an overview of the prototype development effort, status, and future plans including fabrication.

Slides FRIBA07 [9.655 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-FRIBA07

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Received ※ 15 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 11 July 2023

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