An-In-situ Photocathode Loading System for the SLC Polarized Electron Gun
نویسندگان
چکیده
An ultra-high vacuum loadlock system capable of operating at high voltage has been added to Lhe SLC Polarized Electron Gun. The unit incorporates facilities for heat cleaning, activating and measuring the quantum efficiency of photocathodes. A tray of up to four photocathodes can be exchanged without bringing the activation unit or gun up to atmosphere. Low voltage quantum efficiencies of 20% have been obtained for bulk GaAs at 633 nm and 6% for a 0.3 micron GaAs layer at 755 mu. Results for other cathodes as well as operational characteristics are discussed.
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تاریخ انتشار 1992