Author: Spataro, B.
Paper Title Page
TUPA80 Cyborg Beamline Development Updates 512
 
  • G.E. Lawler, A. Fukasawa, N. Majernik, J.R. Parsons, J.B. Rosenzweig, Y. Sakai
    UCLA, Los Angeles, California, USA
  • F. Bosco
    Sapienza University of Rome, Rome, Italy
  • Z. Li, S.G. Tantawi
    SLAC, Menlo Park, California, USA
  • B. Spataro
    LNF-INFN, Frascati, Italy
  
  Funding: This work was supported by the Center for Bright Beams, National Science Foundation Grant No. PHY-1549132 and DOE Contract DE-SC0020409.
Xray free elec­tron laser (XFEL) fa­cil­i­ties in their cur­rent form are large, costly to main­tain, and in­ac­ces­si­ble due to their min­i­mal sup­ply and high de­mand. It is then ad­van­ta­geous to con­sider minia­tur­iz­ing XFELs through a va­ri­ety of means. We hope to in­crease beam bright­ness from the pho­toin­jec­tor via high gra­di­ent op­er­a­tion (>120 MV/m) and cryo­genic tem­per­a­ture op­er­a­tion at the cath­ode (<77K). To this end we have de­signed and fab­ri­cated our new CrYo­genic Bright­ness-Op­ti­mized Ra­diofre­quency Gun (CY­B­GORG). The pho­to­gun is 0.5 cell so much less com­pli­cated than our even­tual 1.6 cell pho­toin­jec­tor. It will serve as a pro­to­type and test bed for cath­ode stud­ies in a new cryo­genic and very high gra­di­ent regime. We pre­sent here the fab­ri­cated struc­ture, progress to­wards com­mis­sion­ing, and beam­line sim­u­la­tions. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA80  
About • Received ※ 02 August 2022 — Accepted ※ 06 August 2022 — Issue date ※ 09 October 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA81 Design of a High-Power RF Breakdown Test for a Cryocooled C-Band Copper Structure 516
 
  • G.E. Lawler, A. Fukasawa, J.R. Parsons, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • Z. Li, S.G. Tantawi
    SLAC, Menlo Park, California, USA
  • A. Mostacci
    Sapienza University of Rome, Rome, Italy
  • E.I. Simakov, T. Tajima
    LANL, Los Alamos, New Mexico, USA
  • B. Spataro
    LNF-INFN, Frascati, Italy
  
  Funding: This work was supported by the DOE Contract DE-SC0020409.
High-gra­di­ent RF struc­tures ca­pa­ble of main­tain­ing gra­di­ents in ex­cess of 250 MV/m are crit­i­cal in sev­eral con­cepts for fu­ture elec­tron ac­cel­er­a­tors. Con­cepts such as the ul­tra-com­pact free elec­tron laser (UC-XFEL) and the Cool Cop­per Col­lider (C3) plan to ob­tain these gra­di­ents through the cryo­genic op­er­a­tion (<77K) of nor­mal con­duct­ing cop­per cav­i­ties. Break­down rates, the most sig­nif­i­cant gra­di­ent lim­i­ta­tion, are sig­nif­i­cantly re­duced at these low tem­per­a­tures, but the pre­cise physics is com­plex and in­volves many in­ter­act­ing ef­fects. High-power RF break­down mea­sure­ments at cryo­genic tem­per­a­tures are needed at the less ex­plored C-band fre­quency (5.712 GHz), which is of great in­ter­est for the afore­men­tioned con­cepts. On be­half of a large col­lab­o­ra­tion of UCLA, SLAC, LANL, and INFN, the first C-band cryo­genic break­down mea­sure­ments will be made using a LANL RF test in­fra­struc­ture. The 2-cell geom­e­try de­signed for test­ing will be mod­i­fi­ca­tions of the dis­trib­uted cou­pled reen­trant de­sign used to ef­fi­ciently power the cells while stay­ing below the lim­it­ing val­ues of peak sur­face elec­tric and mag­netic fields. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA81  
About • Received ※ 29 July 2022 — Accepted ※ 02 August 2022 — Issue date ※ 08 August 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)