Keyword: cryogenics
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MOPAB313 Argonaut - A Robotic System for Cryogenic Environments detector, diagnostics, operation, electron 966
 
  • W. Pellico, N.M. Curfman, M. Wong-Squires
    Fermilab, Batavia, Illinois, USA
  
  Funding: Department of Energy
Fer­mi­lab and the HEP com­mu­nity in­vest sig­nif­i­cant re­sources into liq­uid argon de­tec­tors. The largest and most ex­pen­sive of these de­tec­tors will be lo­cated in the Deep Un­der­ground Neu­trino Ex­per­i­ment (DUNE). How­ever, re­cent ex­pe­ri­ences have shown that there are lim­ited av­enues of mon­i­tor­ing, in­ter­ven­tion, and in­ter­ac­tion in the in­ter­nal liq­uid en­vi­ron­ment. This pro­posal shows a tech­no­log­i­cal path that could pro­vide a valu­able tool to en­sure or at least im­prove the man­age­ment of these HEP de­tec­tors. The de­vel­op­ment of a ro­botic sys­tem named Arg­onaut will demon­strate sev­eral tech­nolo­gies in­clud­ing 1) demon­stra­tion of suit­able mo­bil­ity of a small ro­botic de­vice at liq­uid argon tem­per­a­tures, 2) demon­stra­tion of wire­less com­mu­ni­ca­tion, 3) demon­stra­tion of im­proved di­ag­nos­tics ca­pa­bil­i­ties - such as tun­able op­tics with mo­tion con­trol, 4) demon­stra­tion of in­ter­con­nec­tiv­ity of a ro­botic sys­tem with hard­ware re­sid­ing within the de­tec­tor. This ini­tial re­search will be a seed for ex­tended de­vel­op­ment in cold ro­bot­ics and as­so­ci­ated tech­nolo­gies. This work will allow FNAL to con­tribute a sig­nif­i­cant tech­nol­ogy ca­pa­bil­ity to re­cent ef­forts to cryo­genic de­tec­tor op­er­a­tions. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB313  
About • paper received ※ 19 May 2021       paper accepted ※ 21 May 2021       issue date ※ 25 August 2021  
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MOPAB329 Operations of Copper Cavities at Cryogenic Temperatures cavity, coupling, linac, ECR 1020
 
  • H. Wang, U. Ratzinger, M. Schuett
    IAP, Frankfurt am Main, Germany
  
  How the anom­alous skin ef­fect by cop­per af­fects the ef­fi­ciency of cop­per- cav­i­ties will be stud­ied in the ex­per­i­ment, es­pe­cially at lower tem­per­a­tures. The ac­cu­rate qual­ity fac­tor Q and res­o­nant fre­quency of three coax­ial cav­i­ties will be mea­sured over the tem­per­a­ture range from 300 to 22 K. The three coax­ial cav­i­ties have the same struc­ture, but dif­fer­ent lengths, which cor­re­spond to res­o­nant fre­quen­cies: around 100 MHz, 220 MHz and 340 MHz. The mo­ti­va­tion is to check the fea­si­bil­ity of an ef­fi­cient pulsed, liq­uid ni­tro­gen cooled ion linac.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB329  
About • paper received ※ 19 May 2021       paper accepted ※ 07 June 2021       issue date ※ 02 September 2021  
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MOPAB364 Shielded Pair Method for Cylindrical Surface Resistance Measurement at Cryogenic Temperature factory, dipole, coupling, simulation 1132
 
  • K. Brunner, S. Calatroni, F. Caspers
    CERN, Geneva, Switzerland
  • D. Barna
    Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, Budapest, Hungary
  
  The shielded pair res­onator method was al­ready used in the past at CERN to mea­sure the sur­face re­sis­tiv­ity of the LHC beam screen both at room tem­per­a­ture and cryo­genic tem­per­a­ture. We have re­fined and adapted the mea­sure­ment to be able to mea­sure other types of beam screens and also to op­er­ate in a strong dipo­lar mag­netic field. This is nec­es­sary for test­ing the prop­er­ties of HTS coated beam screens or the pos­si­ble ef­fects of coat­ings and sur­face treat­ments for e-cloud sup­pres­sion. Sev­eral cal­i­bra­tion runs were done at cryo­genic tem­per­a­tures (4.2 K) mea­sur­ing the sur­face re­sis­tiv­ity of a cop­per pipe to iden­tify the pre­ci­sion, sta­bil­ity and re­pro­ducibil­ity achiev­able using this method. This work de­scribes the chal­lenges of the mea­sure­ment and ways to mit­i­gate them.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB364  
About • paper received ※ 17 May 2021       paper accepted ※ 22 June 2021       issue date ※ 12 August 2021  
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TUPAB092 Demonstration FELs Using UC-XFEL Technologies at the SAMURAI Laboratory FEL, undulator, electron, laser 1592
 
  • N. Majernik, G. Andonian, O. Camacho, A. Fukasawa, G.E. Lawler, W.J. Lynn, B. Naranjo, J.B. Rosenzweig, Y. Sakai, O. Williams
    UCLA, Los Angeles, California, USA
  • R. Robles
    SLAC, Menlo Park, California, USA
  
  Funding: DOE HEP Grant DE-SC0020409, National Science Foundation Grant No. PHY-1549132
The ul­tra-com­pact x-ray free-elec­tron laser (UC-XFEL), de­scribed in [J. B. Rosen­zweig, et al. 2020 New J. Phys. 22 093067], com­bines sev­eral cut­ting edge beam physics tech­niques and tech­nolo­gies to re­al­ize an x-ray free elec­tron laser at a frac­tion of the cost and foot­print of ex­ist­ing XFEL in­stal­la­tions. These el­e­ments in­clude cryo­genic, nor­mally con­duct­ing RF struc­tures for both the gun and linac, IFEL bunch com­pres­sion, and short-pe­riod un­du­la­tors. In this work, sev­eral step­ping-stone, demon­stra­tor sce­nar­ios under dis­cus­sion for the UCLA SAMU­RAI Lab­o­ra­tory are de­tailed and sim­u­lated, em­ploy­ing dif­fer­ent sub­sets of these el­e­ments. The cost, foot­print, and tech­nol­ogy risk for these sce­nar­ios are con­sid­ered in ad­di­tion to the an­tic­i­pated en­gi­neer­ing and physics ex­pe­ri­ence gained. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB092  
About • paper received ※ 19 May 2021       paper accepted ※ 11 August 2021       issue date ※ 02 September 2021  
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TUPAB270 Thermal Transition Design and Beam Heat-load Estimation for the COLDDIAG Refurbishment vacuum, operation, diagnostics, simulation 2097
 
  • H.J. Cha, N. Glamann, A.W. Grau, A.-S. Müller, D. Saez de Jauregui
    KIT, Eggenstein-Leopoldshafen, Germany
  
  Funding: This work is supported by the BMBF project 05H18VKRB1 HIRING (Federal Ministry of Education and Research).
The COLD­DIAG (cold vac­uum cham­ber for beam heat load di­ag­nos­tics) de­vel­oped at Karl­sruhe In­sti­tute of Tech­nol­ogy has been mod­i­fied for more stud­ies at cryo­genic tem­per­a­tures dif­fer­ent from the pre­vi­ous op­er­a­tions at 4 K in a cold bore and at 50 K in a ther­mal shield. The key com­po­nents in this cam­paign are two ther­mal tran­si­tions con­nect­ing both ends of the bore at 50 K with the shield at the same or higher tem­per­a­ture. In this paper, we pre­sent de­sign ef­forts for the com­pact tran­si­tions, al­lowed heat in­takes to the cool­ing power mar­gin and me­chan­i­cal ro­bust­ness in the cryo­genic en­vi­ron­ment. A man­u­fac­ture scheme for the tran­si­tion and its pe­riph­eral is also given. In ad­di­tion, the beam heat loads in the re­fur­bished COLD­DIAG are es­ti­mated in terms of the ac­cel­er­a­tor beam pa­ra­me­ters. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB270  
About • paper received ※ 12 May 2021       paper accepted ※ 02 June 2021       issue date ※ 12 August 2021  
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TUPAB372 Status of the Quadrupole Doublet Module Series Manfacturing quadrupole, alignment, site, synchrotron 2388
 
  • T. Winkler, A. Bleile, L.H.J. Bozyk, V.I. Datskov, J. Ketter, P. Kowina, J.P. Meier, N. Pyka, C. Roux, P.J. Spiller, K. Sugita, A. Waldt, St. Wilfert
    GSI, Darmstadt, Germany
  
  The 83 Quadru­pole Dou­blet Mod­ules (QDM) for the heavy-ion-syn­chro­tron SIS100 of the FAIR pro­ject at GSI are highly in­te­grated cryo­genic mod­ules con­tain­ing mul­ti­ple mag­nets. Each of eleven dif­fer­ent QDM types con­sists of two units, where one unit con­sists of one quadru­pole mag­net as well as cor­rec­tor mag­nets de­pend­ing on the mod­ules po­si­tion in the ac­cel­er­a­tor Ion-Op­ti­cal Lat­tice. Ad­di­tion­ally, the QDMs con­tain cryo­genic col­li­ma­tors, beam di­ag­nos­tics, as well as cryo­genic UHV beam pipes. The mod­ules con­tain parts from mul­ti­ple sup­pli­ers in­creas­ing the lo­gis­tics be­hinds the QDMs de­sign fur­ther. We pre­sent the process of the mod­ule in­te­gra­tion, give de­tails on the cur­rent in­te­gra­tion sta­tus and pre­sent an out­look on the time­line for the QDM in­te­gra­tion plan­ning.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB372  
About • paper received ※ 18 May 2021       paper accepted ※ 02 June 2021       issue date ※ 21 August 2021  
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TUPAB380 Testing of the First of Series Quadrupole Doublet Module for the SIS100 Synchrotron quadrupole, operation, synchrotron, superconducting-magnet 2409
 
  • P. Aguar Bartolome, M. Al Ghanem, M. Becker, A. Bleile, R. Bluemel, L.H.J. Bozyk, V.I. Datskov, W. Freisleben, A. Kario, P. Kowina, K.K. Kozlowski, F. Kurian, S. Lindner, J.P. Meier, T. Miertsch, S.S. Mohite, V.P. Plyusnin, I. Pongrac, C. Roux, C. Schroeder, P.J. Spiller, K. Sugita, A. Szwangruber, P.B. Szwangruber, F. Walter, H. Welker, St. Wilfert, T. Winkler, S. Zeller
    GSI, Darmstadt, Germany
  
  A new in­ter­na­tional fa­cil­ity for an­tipro­ton and ion re­search (FAIR) is cur­rently under con­struc­tion in Darm­stadt, Ger­many. The high in­ten­sity pri­mary beam re­quired for dif­fer­ent re­search ex­per­i­ments will be pro­vided by the SIS100 heavy ion syn­chro­tron. The syn­chro­tron is com­posed of fast cy­cling su­per­con­duct­ing mag­nets from which about 300 will be in­te­grated in Quadru­pole Dou­blet Mod­ules (QDM). Each mod­ule con­sists of two units com­posed of a quadru­pole and cor­rec­tor mag­nets. The First of Se­ries Quadru­pole Dou­blet Mod­ule was de­liv­ered to the test fa­cil­ity at GSI in No­vem­ber 2019. The as­sem­bled dou­blet was sub­jected to a ded­i­cated test pro­gram to ver­ify the func­tion­al­ity of the mod­ule com­po­nents at cryo­genic tem­per­a­ture and op­er­at­ing con­di­tions. The re­sults ob­tained dur­ing the test­ing cam­paign will be pre­sented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB380  
About • paper received ※ 19 May 2021       paper accepted ※ 18 June 2021       issue date ※ 02 September 2021  
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TUPAB381 Thermal Analysis of the RHIC Arc Dipole Magnet Cold Mass with the EIC Beam Screen dipole, vacuum, electron, hadron 2413
 
  • S.K. Nayak, M. Anerella, M. Blaskiewicz, J.M. Brennan, R.C. Gupta, M. Mapes, G.T. McIntyre, S. Peggs, R. Than, J.E. Tuozzolo, S. Verdú-Andrés, D. Weiss
    BNL, Upton, New York, USA
  
  Funding: Funding agency Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
The EIC will make use of the ex­ist­ing RHIC stor­age rings with their su­per­con­duct­ing (SC) mag­net arcs. A stain­less-steel beam screen with co-lam­i­nated cop­per and a thin amor­phous car­bon (aC) film on the inner sur­face will be in­stalled in the beam pipe of the SC mag­nets. The cop­per will re­duce the beam-in­duced re­sis­tive-wall (RW) heat­ing from op­er­a­tion with the higher in­ten­sity EIC beams, that if not ad­dressed would make the mag­nets quench. Lim­it­ing the RW heat­ing is also im­por­tant to achieve an ad­e­quately low vac­uum level. The aC coat­ing will re­duce sec­ondary elec­tron yield which could also cause heat­ing and limit in­ten­sity. Among all the RHIC SC mag­nets, the arc dipoles pre­sent the biggest chal­lenge to the de­sign and in­stal­la­tion of beam screens. The arc dipoles, which make up for 78% (2.5 km) length of all SC mag­nets in RHIC, ex­pect the largest RW heat­ing due to their small­est aper­ture. These mag­nets are also the longest (9.45 m each), thus ex­pe­ri­enc­ing the largest tem­per­a­ture rise over their length, and have a large sagitta (48.5 mm) that in­creases the dif­fi­culty to in­stall the beam screen in place. This paper pre­sents a de­tailed ther­mal analy­sis of the mag­net-screen sys­tem. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB381  
About • paper received ※ 19 May 2021       paper accepted ※ 20 July 2021       issue date ※ 23 August 2021  
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TUPAB383 Magnetic Field Performance of the First Serial Quadrupole Units for the SIS100 Synchrotron of FAIR quadrupole, synchrotron, multipole, heavy-ion 2417
 
  • V.V. Borisov, O. Golubitsky, H.G. Khodzhibagiyan, B.Yu. Kondratiev, M.M. Shandov
    JINR, Dubna, Moscow Region, Russia
  • E.S. Fischer, M.A. Kashunin, S.A. Kostromin, I. Nikolaichuk, T. Parfylo, A.V. Shemchuk, D.A. Zolotykh
    JINR/VBLHEP, Dubna, Moscow region, Russia
  
  The FAIR pro­ject is a new in­ter­na­tional ac­cel­er­a­tor com­plex, cur­rently under con­struc­tion in Darm­stadt, Ger­many. The heavy-ion syn­chro­tron SIS100 is the main ac­cel­er­a­tor of the whole com­plex. It will pro­vide high-in­ten­sity pri­mary beams with a mag­netic rigid­ity of 100 Tm and a max­i­mum rep­e­ti­tion rate up to 4 Hz. The se­ries pro­duc­tion and test­ing of su­per­con­duct­ing quadru­pole units began in 2020 at JINR, Dubna. The first batch of units was de­liv­ered to Ger­many in Sep­tem­ber 2020. Each unit is sub­jected to a com­pre­hen­sive test­ing pro­gram both at am­bi­ent tem­per­a­ture and under cryo­genic con­di­tions. We pre­sent the per­for­mance char­ac­ter­is­tics of the first quadru­pole units (con­sist­ing of a lat­tice quadru­pole mag­net and cor­rect­ing mag­net me­chan­i­cally and hy­drauli­cally cou­pled to a quadru­pole). The main at­ten­tion is paid to the field qual­ity of the se­ries of 6 quadrupoles mea­sured by the same probe.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB383  
About • paper received ※ 19 May 2021       paper accepted ※ 02 June 2021       issue date ※ 01 September 2021  
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TUPAB391 Cryopanels in the Room Temperature Heavy Ion Synchrotron SIS18 simulation, vacuum, quadrupole, heavy-ion 2435
 
  • S. Aumüller, L.H.J. Bozyk, P.J. Spiller
    GSI, Darmstadt, Germany
  • K. Blaum
    MPI-K, Heidelberg, Germany
  
  The FAIR com­plex at the GSI Helmholtzzen­trum will gen­er­ate heavy ion beams of ul­ti­mate in­ten­si­ties. To achieve this goal, medium charge states have to be used. How­ever, the prob­a­bil­ity for charge ex­change in col­li­sions with resid­ual gas par­ti­cles of such ions is much higher than for higher charge states. In order to lower the resid­ual gas den­sity to ex­treme high vac­uum con­di­tions, 65% of the cir­cum­fer­ence of SIS18 are al­ready coated with NEG, which pro­vides high and dis­trib­uted pump­ing speed. Nev­er­the­less, nobel and no­bel-like com­po­nents, which have very high ion­iza­tion cross sec­tions, do not get pumped by this coat­ing. A cryo­genic en­vi­ron­ment at mod­er­ate tem­per­a­tures, i.e. at 50-80K, pro­vides high pump­ing speed for all heavy resid­ual gas par­ti­cles. The only typ­i­cal resid­ual gas species, that can­not be pumped at this tem­per­a­ture is hy­dro­gen. With an ad­di­tional NEG coat­ing the pump­ing will be op­ti­mized for all resid­ual gas par­ti­cles. The in­stal­la­tion of cryo­genic sur­faces in the ex­ist­ing room tem­per­a­ture syn­chro­tron SIS18 at GSI has been in­ves­ti­gated. A pro­to­type quadru­pole cham­ber with cryo­genic sur­faces, first mea­sure­ments, and sim­u­la­tions of the adapted ac­cel­er­a­tor are pre­sented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB391  
About • paper received ※ 19 May 2021       paper accepted ※ 31 August 2021       issue date ※ 25 August 2021  
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WEPAB096 RF Testbed for Cryogenic Photoemission Studies cathode, gun, electron, brightness 2810
 
  • G.E. Lawler, A. Fukasawa, N. Majernik, J.B. Rosenzweig, A. Suraj, M. Yadav
    UCLA, Los Angeles, California, USA
  • Z. Li
    SLAC, Menlo Park, California, USA
  • M. Yadav
    The University of Liverpool, Liverpool, United Kingdom
  • M. Yadav
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  
  Funding: This work was supported by the Center for Bright Beams, National Science Foundation Grant No. PHY-1549132 and DOE Contract DE-SC0020409
Pro­duc­ing higher bright­ness beams at the cath­ode is one of the main fo­cuses for fu­ture elec­tron beam ap­pli­ca­tions. For pho­to­cath­odes op­er­at­ing close to their emis­sion thresh­old, the cath­ode lat­tice tem­per­a­ture be­gins to dom­i­nate the min­i­mum achiev­able in­trin­sic emit­tance. At UCLA, we are de­sign­ing a ra­diofre­quency (RF) test bed for mea­sur­ing the tem­per­a­ture de­pen­dence of the mean trans­verse en­ergy (MTE) and quan­tum ef­fi­ciency for a num­ber of can­di­date cath­ode ma­te­ri­als. We in­tend to quan­tify the at­tain­able bright­ness im­prove­ments at the cath­ode from cryo­genic op­er­a­tion and es­tab­lish a proof-of-prin­ci­ple cryo­genic RF gun for fu­ture stud­ies of a 1.6 cell cryo­genic pho­toin­jec­tor for the UCLA ultra com­pact XFEL con­cept (UC-XFEL). The test bed will use a C-band 0.5-cell RF gun de­signed to op­er­ate down to 40K, pro­duc­ing an on-axis ac­cel­er­at­ing field of 120 MV/m. The cryo­genic sys­tem uses con­duc­tion cool­ing and a load-lock sys­tem is being de­signed for trans­port and stor­age of air-sen­si­tive high bright­ness cath­odes. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB096  
About • paper received ※ 19 May 2021       paper accepted ※ 24 June 2021       issue date ※ 15 August 2021  
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WEPAB098 Cryogenic Component and Material Testing for Compact Electron Beamlines cavity, cathode, electron, gun 2818
 
  • G.E. Lawler, N. Majernik, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  
  Funding: This work was supported by the Center for Bright Beams, National Science Foundation Grant No. PHY-1549132 and DOE Contract DE-SC0020409
Cryo­genic regimes of op­er­a­tion are, for var­i­ous rea­sons, highly ad­van­ta­geous for nor­mal con­duct­ing ac­cel­er­a­tor struc­tures. Liq­uid cryo­gen-based sys­tems are costly to im­ple­ment and main­tain. As a re­sult, de­vel­op­ing cryo­genic test fa­cil­i­ties at a smaller more cost ef­fec­tive scale using cryo-cool­ers is at­trac­tive. Be­fore real im­ple­men­ta­tions of a cryo-cooler based beam­line, a sig­nif­i­cant amount of in­for­ma­tion is nec­es­sary re­gard­ing the be­hav­ior and prop­er­ties of var­i­ous com­po­nents and ma­te­ri­als at cryo­genic tem­per­a­tures. Find­ing this in­for­ma­tion lack­ing for our par­tic­u­lar beam­line case and by ex­ten­sion sim­i­lar elec­tron beam­lines, we en­deavor to gen­er­ate a thor­ough beam­line-rel­e­vant ma­te­r­ial and com­po­nent prop­er­ties down to the range of a liq­uid ni­tro­gen tem­per­a­tures (77 K) and the nom­i­nal op­er­at­ing tem­per­a­ture of a mod­est Gif­ford-McMa­hon cry­ocooler (45 K). 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB098  
About • paper received ※ 19 May 2021       paper accepted ※ 01 July 2021       issue date ※ 25 August 2021  
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WEPAB111 Controlled Degradation by Oxygen Exposure in the Performance of a Ag (100) Single-Crystal Photocathode cathode, experiment, electron, emittance 2856
 
  • L.A.J. Soomary, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • L.B. Jones, T.C.Q. Noakes
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  
  The search for high-per­for­mance pho­to­cath­ode elec­tron sources is a pri­or­ity in the ac­cel­er­a­tor sci­ence com­mu­nity. The sur­face char­ac­ter­is­tics of a pho­to­cath­ode de­fine many im­por­tant fac­tors of the pho­toe­mis­sion in­clud­ing the work func­tion, in­trin­sic emit­tance, and quan­tum ef­fi­ciency of the pho­to­cath­ode. These fac­tors in turn de­fine the elec­tron beam per­for­mance which is mea­sur­able as nor­mal­ized emit­tance, bright­ness, and en­ergy spread*. Strate­gies for im­prov­ing these pa­ra­me­ters vary, but un­der­stand­ing and in­flu­enc­ing the rel­e­vant cath­ode sur­face physics which un­der­pin these at­trib­utes is a pri­mary focus for the elec­tron source com­mu­nity**. As such, pure metal pho­to­cath­odes and their per­for­mance at UV wave­lengths are of in­ter­est as seen at the LCLS at SLAC and CLARA at Dares­bury. We pre­sent per­for­mance data for an Ag (100) sin­gle-crys­tal pho­to­cath­ode under il­lu­mi­na­tion at 266 nm wave­length, with known lev­els of sur­face rough­ness, using our Trans­verse En­ergy Spread Spec­trom­e­ter (TESS)*** both at room and cryo­genic tem­per­a­tures. Cru­cially our data shows the ef­fect of pro­gres­sive degra­da­tion in the photo-cath­ode per­for­mance as a con­se­quence of ex­po­sure to con­trolled lev­els of oxy­gen.
* D.H. Dowell, et al., Nucl. Instr. and Meth. A (2010), doi:10.1016/j.nima.2010.03.104
** Appl. Phys. Lett. 89, 224103 (2006); doi:10.1063/1.2387968
*** Proc. FEL’13, TUPPS033, 290-293
 		 
poster icon Poster WEPAB111 [0.866 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB111  
About • paper received ※ 20 May 2021       paper accepted ※ 22 June 2021       issue date ※ 31 August 2021  
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WEPAB189 EIC Hadron Beamline Vacuum Studies vacuum, hadron, electron, emittance 3060
 
  • D. Weiss, M. Mapes, J.E. Tuozzolo, S. Verdú-Andrés
    BNL, Upton, New York, USA
  
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Ninety per­cent of the EIC hadron ring beam­line is cold-bore com­pris­ing strings of in­ter­con­nected 4.55 K RHIC su­per­con­duct­ing (SC) mag­nets. The EIC op­er­at­ing spec­i­fi­ca­tion re­quires shorter bunches and 3x higher in­ten­sity beams which are not ap­pro­pri­ate for the pre­sent RHIC stain­less steel cold-bore beam tube. The in­ten­sity and emit­tance of the hadron beams will de­grade due to in­ter­ac­tions with resid­ual gas or vac­uum in­sta­bil­i­ties aris­ing from the ex­pected re­sis­tive-wall (RW) heat­ing, elec­tron clouds, and beam-in­duced des­orp­tion mech­a­nisms. With­out strate­gies to limit RW heat­ing, major cryo­genic sys­tem mod­i­fi­ca­tions are needed to pre­vent SC mag­net quenches. The SC mag­net cold-bore beam tubes will be equipped with a high RRR cop­per clad stain­less steel sleeve to sig­nif­i­cantly re­duce RW heat­ing and so the ef­fect on the SC mag­net cryo­genic heat load and tem­per­a­ture. A thin amor­phous car­bon film ap­plied to the beam fac­ing cop­per sur­face will sup­press elec­tron cloud for­ma­tion. This paper dis­cusses the vac­uum re­quire­ments im­posed by the EIC hadron beams and the plans to achieve the nec­es­sary vac­uum and ther­mal sta­bil­ity that en­sure ac­cept­able beam qual­ity and life­time. 		 
poster icon Poster WEPAB189 [3.321 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB189  
About • paper received ※ 17 May 2021       paper accepted ※ 25 August 2021       issue date ※ 26 August 2021  
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WEPAB339 Beam-Induced Surface Modification of the LHC Beam Screens: The Reason for the High Heat Load in Some LHC Arcs? electron, dipole, hadron, ECR 3479
 
  • V. Petit, P. Chiggiato, M. Himmerlich, G. Iadarola, H. Neupert, M. Taborelli, D.A. Zanin
    CERN, Geneva, Switzerland
  
  All over Run 2, the LHC beam-in­duced heat load ex­hib­ited a wide scat­ter­ing along the ring. Stud­ies as­cribed the heat source to elec­tron cloud build-up, in­di­cat­ing an un­ex­pect­edly high Sec­ondary Elec­tron Yield (SEY) of the beam screen sur­face in some LHC re­gions. Dur­ing the Long Shut­down 2, the beam screens of a low and a high heat load di­pole were ex­tracted. Their inner cop­per sur­face was analysed in the lab­o­ra­tory to com­pare their SEY and sur­face com­po­si­tion. While find­ings on the low heat load beam screens are com­pat­i­ble with ex­pec­ta­tions from lab­o­ra­tory stud­ies of cop­per con­di­tion­ing and de­con­di­tion­ing mech­a­nisms, an ex­tremely low car­bon amount and the pres­ence of CuO (non-na­tive sur­face oxide) are ob­served on the high heat-load beam screens. The az­imuthal dis­tri­b­u­tion of CuO cor­re­lates with the den­sity and en­ergy of elec­tron im­pinge­ment. Such chem­i­cal mod­i­fi­ca­tions in­crease the SEY and in­hibit the full con­di­tion­ing of af­fected sur­faces. This work shows a di­rect cor­re­la­tion be­tween the ab­nor­mal LHC heat load and the sur­face prop­er­ties of its beam screens, open­ing the door to the de­vel­op­ment of cu­ra­tive so­lu­tions to over­come this crit­i­cal lim­i­ta­tion.  
poster icon Poster WEPAB339 [2.247 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB339  
About • paper received ※ 19 May 2021       paper accepted ※ 22 June 2021       issue date ※ 16 August 2021  
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WEPAB355 Series Production of the SIS100 Cryocatchers quadrupole, site, vacuum, heavy-ion 3529
 
  • L.H.J. Bozyk, S. Ahmed, P.J. Spiller
    GSI, Darmstadt, Germany
  
  The su­per­con­duct­ing heavy ion syn­chro­tron SIS100, which is the main ac­cel­er­a­tor of the FAIR-fa­cil­ity will be equipped with cry­ocatcher to sup­press dy­namic vac­uum ef­fects and to as­sure a re­li­able op­er­a­tion of high in­ten­sity heavy-ion beams. Sub­se­quent to the suc­cess­ful val­i­da­tion of the pro­to­type in 2011 as well as a First-of-Se­ries cry­ocatcher, the se­ries pro­duc­tion of 60 cry­ocatcher mod­ules mean­while has been com­pleted. It was re­leased in 2018 after fur­ther de­sign op­ti­miza­tions. Key find­ings from the se­ries pro­duc­tion and ac­cep­tance tests are pre­sented as well. The First-of-Se­ries cry­ocatcher has been in­te­grated into the First-of-Se­ries quadru­pole mod­ule and has un­der­gone sev­eral tests. These re­sults are also il­lus­trated in this re­port.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB355  
About • paper received ※ 19 May 2021       paper accepted ※ 06 July 2021       issue date ※ 16 August 2021  
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WEPAB372 Design and Construction of Uninterruptible Paralleling Transfer Switches for an Emergency Power System in Taiwan Light Source operation, controls, ECR, MMI 3581
 
  • Y.F. Chiu, W.S. Chan, K.C. Kuo, Y.-C. Lin
    NSRRC, Hsinchu, Taiwan
  
  The ATS of an emer­gency power sys­tem in Util­ity Build­ing II has op­er­ated over 18 years; in re­cent years the fail­ure rate is grad­u­ally in­creas­ing be­cause of aged com­po­nents. To im­prove old switches, schemes of up­grad­ing and de­vel­op­ing new and ef­fi­cient trans­fer switches have been con­ducted cau­tiously. A new de­vice named an Un­in­ter­rupt­ible Par­al­lel­ing Trans­fer Switch (UPTS) is de­signed and im­ple­mented to re­place an ex­ist­ing ATS to en­hance the per­for­mance to meet the re­quire­ments of un­in­ter­rupted power trans­fer. The UPTS can un­in­ter­rupt­edly switch the grid power to emer­gency power of a backup gen­er­a­tor dur­ing a planned util­ity power out­age, and also ex­actly switch emer­gency power to the grid power un­in­ter­rupt­edly when the util­ity power is re­stored. If grid power is un­ex­pect­edly lost, UPTS acts like a typ­i­cal ATS, au­to­mat­i­cally trans­fer­ring power from a pri­mary source to a backup source with switch­ing du­ra­tion a few sec­onds. A prac­ti­cal UPTS has been as­sem­bled and in­stalled in Util­ity Build­ing II and has per­formed well ef­fec­tively to elim­i­nate power-switch­ing tran­sients.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB372  
About • paper received ※ 11 May 2021       paper accepted ※ 02 July 2021       issue date ※ 12 August 2021  
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WEPAB376 The Inner Triplet String Facility for HL-LHC: Design and Planning quadrupole, operation, vacuum, MMI 3592
 
  • M.B. Bajko, S. Bertolasi, C. Bertone, S. Blanchard, D. Bozzini, O.S. Brüning, P. Cruikshank, D. De Luca, N. Dos Santos, F. Dragoni, N. Heredia Garcia, A. Herty, A. Kosmicki, S. Le Naour, W. Maan, A. Martínez Sellés, P. Martinez Urios, P. Orlandi, A. Perin, M. Pojer, F. Rodriguez-Mateos, G. Rolando, L. Rossi, H. Thiesen, E. Todesco, E. Vergara Fernandez, D. Wollmann, S. Yammine, J.J. Zawilinski, M. Zerlauth
    CERN, Geneva, Switzerland
  
  In the frame­work of the HL-LHC pro­ject, full-scale in­te­gra­tion and op­er­a­tional tests of the su­per­con­duct­ing mag­net chain, from the inner triplet quadrupoles up to the first sep­a­ra­tion/re­com­bi­na­tion di­pole, are planned in con­di­tions as sim­i­lar as pos­si­ble to the final set-up in the LHC tun­nel. The IT String in­cludes all of the re­quired sys­tems for op­er­a­tion at nom­i­nal con­di­tions, such as vac­uum, cryo­gen­ics, warm and cold pow­er­ing equip­ment, and pro­tec­tion sys­tems. The IT String is in­tended to be both an as­sem­bly, and an in­te­gra­tion test stand, and a full re­hearsal of the sys­tems work­ing in uni­son. It will, closely re­pro­duc­ing the me­chan­i­cal, elec­tri­cal, and thermo-hy­draulic in­ter­faces of the final in­stal­la­tion, as well as al­low­ing a full re­hearsal of the sys­tems work­ing in uni­son. This paper de­scribes the con­cep­tual de­sign, the test stand’s ref­er­ence con­fig­u­ra­tion, and the main goals. It also sum­ma­rizes the sta­tus of the main ac­tiv­i­ties, in­clud­ing the de­tailed de­sign of the test in­fra­struc­ture, pro­cure­ment of main equip­ment, the base­line in­stal­la­tion sched­ule, and major mile­stones. The first ver­sion of the ex­per­i­men­tal pro­gram and the as­so­ci­ated plan­ning are also pre­sented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB376  
About • paper received ※ 19 May 2021       paper accepted ※ 22 July 2021       issue date ※ 22 August 2021  
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THPAB153 Design, Construction and Tests of the Cooling System with a Cryocooler for Cavity Testing cavity, SRF, vacuum, simulation 4056
 
  • P. Pizzol, J.W. Lewellen, E.R. Olivas, E.I. Simakov, T. Tajima
    LANL, Los Alamos, New Mexico, USA
  
  Cryo­geni­cally cooled nor­mal-con­duct­ing cav­i­ties have shown higher gra­di­ents than those op­er­ated at room tem­per­a­ture. We are con­struct­ing a com­pact cool­ing sys­tem with a cry­ocooler to test C-band nor­mal-con­duct­ing cav­i­ties and 1.3 GHz su­per­con­duct­ing cav­i­ties. This paper de­scribes the de­sign, con­struc­tion, and cool­ing test re­sults as well as some low-power cav­ity Q mea­sure­ment re­sults.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB153  
About • paper received ※ 17 May 2021       paper accepted ※ 21 June 2021       issue date ※ 12 August 2021  
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THPAB348 INFN-LASA for the PIP-II LB650 Linac cavity, SRF, linac, experiment 4474
 
  • R. Paparella, M. Bertucci, M. Bonezzi, A. Bosotti, A. D’Ambros, A.T. Grimaldi, P. Michelato, L. Monaco, D. Sertore
    INFN/LASA, Segrate (MI), Italy
  • C. Pagani
    Università degli Studi di Milano & INFN, Segrate, Italy
  
  INFN joined the in­ter­na­tional ef­fort for the PIP-II pro­ject at Fer­mi­lab and it’s going to con­tribute to the low-beta sec­tion of the PIP-II pro­ton linac. In par­tic­u­lar, INFN-LASA is fi­nal­iz­ing its com­mit­ment to de­liver in kind the full set of the LB650 cav­i­ties, namely 36 plus spares 5-cell cav­i­ties at 650 MHz and geo­met­ri­cal beta 0.61. All cav­i­ties, de­signed by INFN-LASA, will be pro­duced and sur­face treated in in­dus­try, qual­i­fied through ver­ti­cal cold test, and de­liv­ered as ready for string in­stal­la­tion. This paper re­ports the sta­tus of INFN’s con­tri­bu­tion to PIP-II and of on­go­ing ac­tiv­i­ties to­ward the ex­per­i­men­tal qual­i­fi­ca­tions of in­fra­struc­tures and pro­to­types.  
poster icon Poster THPAB348 [4.076 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB348  
About • paper received ※ 16 May 2021       paper accepted ※ 01 July 2021       issue date ※ 12 August 2021  
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