AVS 62nd International Symposium & Exhibition
    Vacuum Technology Monday Sessions
       Session VT-MoA

Paper VT-MoA3
XHV Cryopump Performance and Limitations for the Jefferson Lab Polarized Electron Source

Monday, October 19, 2015, 3:00 pm, Room 230B

Session: Extreme High Vacuum
Presenter: Marcy Stutzman, Thomas Jefferson National Accelerator Facility
Authors: M.L. Stutzman, Thomas Jefferson National Accelerator Facility
P.A. Adderley, Thomas Jefferson National Accelerator Facility
M. Poelker, Thomas Jefferson National Accelerator Facility
Correspondent: Click to Email
Cryopumps are typically limited to pressures above 1x10^-10 Torr. This is partly due to the lower pump speeds for hydrogen and other light gasses that dominate systems approaching XHV. Additionally, the cryosorbers and adhesives in cryopumps are typically not compatible with the bakeouts of systems used to reduce water vapor pressure in XHV systems. A series of investigations will be described using a commercial XHV cryopump from Leybold, both alone and with the NEG and ion pumps typically used in the Jefferson Lab electron source. The benefits and limitations of using this cryopump for our applications will be examined.