Author: Owen, P.D.
Paper Title Page
WEPA12 Operational Experience of the New Booster Cryomodule at the Upgraded Injector Test Facility 640
 
  • M.W. Bruker, R. Bachimanchi, J.M. Grames, M.D. McCaughan, J. Musson, P.D. Owen, T.E. Plawski, M. Poelker, T. Powers, H. Wang, Y.W. Wang
    JLab, Newport News, Virginia, USA
  
  Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177.
Since the early 1990s, the in­jec­tor of the CEBAF ac­cel­er­a­tor at Jef­fer­son Lab has re­lied on a nor­mal-con­duct­ing RF graded-beta cap­ture sec­tion to boost the ki­netic en­ergy of the elec­tron beam from 100 / 130 keV to 600 keV for sub­se­quent ac­cel­er­a­tion using a cry­omod­ule hous­ing two su­per­con­duct­ing 5-cell cav­i­ties sim­i­lar to those used through­out the ac­cel­er­a­tor. To sim­plify the in­jec­tor de­sign and im­prove the beam qual­ity, the nor­mal-con­duct­ing RF cap­ture sec­tion and the cry­omod­ule will be re­placed with a new sin­gle booster cry­omod­ule em­ploy­ing a su­per­con­duct­ing, β = 0.6, 2-cell-cav­ity cap­ture sec­tion and a sin­gle, β = 0.97, 7-cell cav­ity. The Up­graded In­jec­tor Test Fa­cil­ity at Jef­fer­son Lab is cur­rently host­ing the new cry­omod­ule to eval­u­ate its per­for­mance with beam be­fore in­stal­la­tion at CEBAF. While demon­strat­ing sat­is­fac­tory per­for­mance of the booster and good agree­ment with sim­u­la­tions, our beam test re­sults also speak to lim­i­ta­tions of ac­cel­er­a­tor op­er­a­tions in a noisy, ther­mally un­reg­u­lated en­vi­ron­ment. 		 
poster icon Poster WEPA12 [3.726 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA12  
About • Received ※ 03 August 2022 — Revised ※ 07 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 06 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA19 HE Production Update at JLab - Introducing an Enhanced Nitrogen Purge for Clean String Assembly 659
 
  • P.D. Owen
    JLab, Newport News, Virginia, USA
  
  A major lim­i­ta­tion to cry­omod­ule per­for­mance is field emis­sion caused by par­tic­u­lates within the su­per­con­duct­ing cav­i­ties. To re­duce con­t­a­m­i­na­tion of the inner sur­faces dur­ing as­sem­bly in a clean­room, the whole string can be con­nected to a purge sys­tem, which main­tains a con­stant over­pres­sure of dry, clean ni­tro­gen gas. Fol­low­ing suc­cesses of sim­i­lar sys­tems at XFEL and Fer­mi­lab, Jef­fer­son Lab fol­lowed this ex­am­ple for the pro­duc­tion of LCLS-II HE cry­omod­ules. Im­ple­ment­ing this sys­tem re­quired new pro­ce­dures, in­fra­struc­ture, and hard­ware, as well as sig­nif­i­cant test­ing of the sys­tem be­fore pro­duc­tion began. This paper will sum­ma­rize the im­ple­mented con­trols and pro­ce­dures, in­clud­ing lessons learned from Fer­mi­lab, as well as the re­sults of mock-up tests. Based on the lat­ter, the sys­tem was used to as­sem­ble the first ar­ti­cle string in April 2022, and was also used dur­ing a re­work re­quired due to is­sues with cold FPC ce­ram­ics two months later. The ben­e­fits of using a purge sys­tem with re­gards to pro­ce­dure, time sav­ings, and added flex­i­bil­ity for po­ten­tial re­work have al­ready proven to pro­vide a sig­nif­i­cant im­prove­ment for the pro­duc­tion of LCLS-II-HE cry­omod­ules at Jef­fer­son Lab.  
poster icon Poster WEPA19 [1.538 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA19  
About • Received ※ 02 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 21 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)