TU1AA —  Plenary Session 4   (30-Aug-22   08:30—10:30)
Chair: C. Madec, CEA-IRFU, Gif-sur-Yvette, France
Paper Title Page
TU1AA01
 Status and Challenges of Nb/Cu SRF Cavities for Superconducting Linac  
 
  • M. Xu, H. Guo, Y. He, S.C. Huang, T.C. Jiang, C.L. Li, L.B. Liu, T. Liu, Z.J. Wang, Z.Q. Yang, S.X. Zhang
    IMP/CAS, Lanzhou, People’s Republic of China
  
  Funding: China initiative Accelerator Driven System Large Research Infrastructures China initiative Accelerator Driven System (2017-000052-75-01-000590)
The re­ac­tor of China ini­tia­tive Ac­cel­er­a­tor Dri­ven Sub-crit­i­cal (CiADS) sys­tem has strict sta­bil­ity re­quire­ments to the dri­ving su­per­con­duct­ing Linac. From the pre­vi­ous op­er­a­tion ex­pe­ri­ences of in­ten­sity su­per­con­duct­ing Linac at in­sti­tute of mod­ern physics (IMP), more than half of the beam trips were in­di­cated to the SRF cav­ity phase un­lock, which is re­lated to the thin-walled low beta SRF cav­ity can not tol­er­ate the he­lium pres­sure vi­bra­tion and en­vi­ron­ment vi­bra­tion. In re­cent years, IMP is de­vel­op­ing low beta Nb/Cu cav­i­ties to pro­vide high sta­bil­ity. The cav­ity was made from a thin layer of high pu­rity nio­bium, then the out­side of cav­ity was cast or coat of high pu­rity cop­per layer. The Nb/Cu cav­i­ties have same SRF per­for­mance as bulk-Nb cav­ity and im­proved me­chan­i­cal sta­bil­ity. The pro­to­type cav­i­ties have been ver­ti­cal tested cou­ple times. A hor­i­zon­tally test­ing fa­cil­ity are under as­sem­bly for val­i­dat­ing the in­te­gra­tion per­for­mance of cav­ity, tuner, and cou­pler. The tech­ni­cal chal­lenges to ob­tain high ther­mal con­duct­ing cop­per layer and high SRF per­for­mance nio­bium cav­ity will be re­port too. 		 
video icon Talk as video stream: 746512109?h=340faeb666  
slides icon Slides TU1AA01 [6.106 MB]  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TU1AA02 Compact, Turn-Key SRF Accelerators 290
SUPCJO04   use link to see paper's listing under its alternate paper code  
 
  • N.A. Stilin, A.T. Holic, M. Liepe, T.I. O’Connell, J. Sears, V.D. Shemelin, J. Turco
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  
  The de­vel­op­ment of sim­pler, com­pact Su­per­con­duct­ing RF (SRF) sys­tems rep­re­sents a new sub­ject of re­search in ac­cel­er­a­tor sci­ence. These com­pact ac­cel­er­a­tors rely on ad­vance­ments made to both Nb3Sn SRF cav­i­ties and com­mer­cial cry­ocool­ers, which to­gether allow for the re­moval of liq­uid cryo­gen­ics from the sys­tem. This ap­proach to SRF cav­ity op­er­a­tion, based on novel con­duc­tion cool­ing schemes, has the po­ten­tial to dras­ti­cally ex­tend the range of ap­pli­ca­tion of SRF tech­nol­ogy. By of­fer­ing ro­bust, non-ex­pert, turn-key op­er­a­tion, such sys­tems en­able the use of SRF ac­cel­er­a­tors for in­dus­trial, med­ical, and small-scale sci­ence ap­pli­ca­tions. This pre­sen­ta­tion will pro­vide an overview of the sig­nif­i­cant progress being made at Cor­nell, Jef­fer­son Lab, and Fer­mi­lab (FNAL), in­clud­ing sta­ble cav­ity op­er­a­tion at 10 MV/m. It will also in­tro­duce the pri­mary chal­lenges of this new field and their po­ten­tial so­lu­tions, along with an overview of the var­i­ous ap­pli­ca­tions which could ben­e­fit the most from this tech­nol­ogy.  
video icon
 
  please see instructions how to view/control embeded videos  
slides icon Slides TU1AA02 [4.683 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-TU1AA02  
About • Received ※ 29 August 2022 — Revised ※ 31 August 2022 — Accepted ※ 01 September 2022 — Issue date ※ 14 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TU1AA03 R&D Towards High Gradient CW SRF Cavities 295
 
  • D. Bafia, P. Berrutti, B. Giaccone, A. Grassellino, D.V. Neuffer, S. Posen, A.S. Romanenko
    Fermilab, Batavia, Illinois, USA
  
  This talk will dis­cuss Fer­mi­lab’s re­cent progress in the sur­face en­gi­neer­ing of su­per­con­duct­ing ra­dio-fre­quency (SRF) cav­i­ties geared to­ward pro­duc­ing si­mul­ta­ne­ously high qual­ity fac­tors and high ac­cel­er­at­ing gra­di­ents in cry­omod­ules. We in­ves­ti­gate pos­si­ble mi­cro­scopic mech­a­nisms that drive im­proved per­for­mance by car­ry­ing out se­quen­tial RF tests on cav­i­ties sub­jected to low tem­per­a­ture bak­ing. We com­pare per­for­mance evo­lu­tion to ob­ser­va­tions made with ma­te­r­ial sci­ence tech­niques and find cor­re­la­tions with ma­te­r­ial pa­ra­me­ters. We also dis­cuss other key ad­vance­ments that en­able high gra­di­ent op­er­a­tion in cry­omod­ules.  
video icon
 
  please see instructions how to view/control embeded videos  
slides icon Slides TU1AA03 [2.007 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-TU1AA03  
About • Received ※ 20 August 2022 — Revised ※ 24 August 2022 — Accepted ※ 30 August 2022 — Issue date ※ 16 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TU1AA04 SWELL and Other SRF Split Cavity Development 300
 
  • F. Peauger
    CERN, Meyrin, Switzerland
  
  An in­no­v­a­tive su­per­con­duct­ing cav­ity topol­ogy has been re­cently pro­posed at CERN and at Lan­caster Uni­ver­sity. It in­te­grates lon­gi­tu­di­nal slots cross­ing per­pen­dic­u­larly the RF sur­face. The RF cur­rent lines run along the slots, in­duc­ing no per­tur­ba­tion of the ac­cel­er­at­ing mode. Thanks to this ap­proach, the cav­ity can be built using halves or quad­rants, which is well ap­pro­pri­ate to pre­cise man­u­fac­tur­ing tech­niques. This con­fig­u­ra­tion al­lows di­rect ac­cess to the RF sur­face, thus fa­cil­i­tat­ing the sur­face prepa­ra­tion and thin film de­po­si­tion process in the case of cav­i­ties based on Nb/Cu tech­nol­ogy. The con­tact faces be­tween the cav­ity parts are moved to the slots’ ends where the elec­tro­mag­netic fields are ex­tremely low, thus re­lax­ing the con­straints on the qual­ity of the as­sem­bly joints. This paper cov­ers the lat­est de­vel­op­ment of a 600 MHz slot­ted el­lip­ti­cal cav­ity called SWELL, which has been pro­posed as an al­ter­na­tive op­tion for the FCC-ee RF sys­tem as well as a sim­pli­fied SWELL ver­sion of a sin­gle cell 1.3 GHz el­lip­ti­cal cav­ity and a new 6 GHz split res­onator made of two halves for su­per­con­duct­ing thin film char­ac­ter­i­za­tion.
Acknowledgement of U. Van Rienen from Rostock University for the use of their GPU based workstations for RF simulations. 		 
video icon
 
  please see instructions how to view/control embeded videos  
slides icon Slides TU1AA04 [4.217 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-TU1AA04  
About • Received ※ 14 August 2022 — Revised ※ 24 August 2022 — Accepted ※ 30 August 2022 — Issue date ※ 02 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TU1AA05
 Progress of Shanghai HIgh repetitioN rate XFEL and Extreme light facility (SHINE)  
 
  • B. Liu, D. Wang, L. Yin
    SARI-CAS, Pudong, Shanghai, People’s Republic of China
  • Z.T. Zhao
    SSRF, Shanghai, People’s Republic of China
  
  The first hard X-ray FEL light source in China, the so-called Shang­hai HIgh rep­e­ti­tioN rate XFEL and Ex­treme light fa­cil­ity (SHINE), is under con­struc­tion. It in­cludes an 8 GeV su­per­con­duct­ing linac and will be built up in 2025. The first CM has been tested and the com­mis­sion­ing of the in­jec­tor will start in 2023. Progress of the SHINE pro­ject will be pre­sented.  
video icon
 
  please see instructions how to view/control embeded videos  
slides icon Slides TU1AA05 [8.558 MB]  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TU1AA06 Next-Generation Nb₃Sn Superconducting RF Cavities 305
SUPCJO08   use link to see paper's listing under its alternate paper code  
 
  • N.M. Verboncoeur, G. Gaitan, M. Liepe, R.D. Porter, L. Shpani, N.A. Stilin, Z. Sun
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  
  Nb3Sn cur­rently is the most promis­ing al­ter­na­tive ma­te­r­ial for next-gen­er­a­tion, higher-per­for­mance SRF cav­i­ties. Sig­nif­i­cant re­cent progress has been made in fur­ther in­creas­ing ef­fi­ciency, max­i­mum field, and demon­strat­ing readi­ness for first ap­pli­ca­tions in ac­tual ac­cel­er­a­tors. This paper will pre­sent an overview of world­wide re­cent progress in mak­ing this ma­te­r­ial a vi­able op­tion for fur­ther ac­cel­er­a­tors.  
slides icon Slides TU1AA06 [6.559 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-TU1AA06  
About • Received ※ 31 August 2022 — Revised ※ 01 September 2022 — Accepted ※ 04 September 2022 — Issue date ※ 09 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)