Author: Bevins, M.E.
Paper Title Page
MOPMB072 LCLS-II-HE Cavity Qualification Testing 279
 
  • J.T. Maniscalco, S. Aderhold, M. Checchin, D. Gonnella, J. Hogan, R.D. Porter
    SLAC, Menlo Park, California, USA
  • T.T. Arkan, D. Bafia, A.T. Cravatta, J.A. Kaluzny, S. Posen
    Fermilab, Batavia, Illinois, USA
  • M.E. Bevins, A.J. Grabowski, C.E. Reece, H. Vennekate
    JLab, Newport News, VA, USA
 
  Ac­cep­tance test­ing of the LCLS-II-HE pro­duc­tion cav­i­ties is ap­prox­i­mately 65% com­plete. In this re­port, we pre­sent de­tails of the test re­sults, in­clud­ing sum­maries of the quench fields, in­trin­sic qual­ity fac­tors, and ex­pe­ri­ence with field emis­sion. We also offer an out­look on the re­main­ing tests to be per­formed.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB072  
About • Received ※ 20 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 03 July 2023 — Issue date ※ 07 July 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPWB120 Flux Expulsion Testing for LCLS-II-HE Cavity Production 876
 
  • J.T. Maniscalco, S. Aderhold, M. Checchin, D. Gonnella, R.D. Porter
    SLAC, Menlo Park, California, USA
  • T.T. Arkan, D. Bafia, J.A. Kaluzny, S. Posen
    Fermilab, Batavia, Illinois, USA
  • M.E. Bevins, A.J. Grabowski, J. Hogan, C.E. Reece, D. Savransky, H. Vennekate
    JLab, Newport News, VA, USA
 
  Ni­tro­gen-doped nio­bium SRF cav­i­ties are sen­si­tive to trapped mag­netic flux, which de­creases the cav­ity in­trin­sic Q₀. Prior ex­per­i­men­tal re­sults have shown that heat treat­ments to 900°C and higher can re­sult in stronger flux ex­pul­sion dur­ing cooldown; the pre­cise tem­per­a­ture re­quired tends to vary by ven­dor lot/ingot of the nio­bium ma­te­r­ial used in the cav­ity cells. For LCLS-II-HE, to en­sure suf­fi­cient flux ex­pul­sion in all cav­i­ties, we built and tested sin­gle-cell cav­i­ties to de­ter­mine this re­quired tem­per­a­ture for each ven­dor lot of nio­bium ma­te­r­ial to be used in cav­ity cells. In this re­port, we pre­sent the re­sults of the sin­gle-cell flux ex­pul­sion test­ing and the Q₀ of the nine-cell cav­i­ties built using the char­ac­ter­ized ven­dor lots. We dis­cuss mix­ing ma­te­r­ial from dif­fer­ent ven­dor lots, ex­am­ine the lessons learned, and fi­nally pre­sent an out­look on pos­si­ble re­fine­ments to the sin­gle-cell tech­nique.  
DOI • reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB120  
About • Received ※ 15 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 03 July 2023 — Issue date ※ 13 July 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)