Polarized Photocathode R&D for Future Linear Collliders

Conference · Fri Jan 23 04:00:00 EST 2009

OSTI ID:946449

Zhou, F; Brachmann, A; Maruyama, T; Sheppard, J C

It is a challenge to generate full charge electrons from the electron sources without compromising polarization for the proposed ILC and CLIC. It is essential to advance polarized photocathodes to meet the requirements. SLAC has worldwide unique dedicated test facilities, Cathode Test System and dc-Gun Test Laboratory, to fully characterize polarized photocathodes. Recent systematic measurements on a strained-well InAlGaAs/AlGaAs cathode at the facilities show that 87% polarization and 0.3% QE are achieved. The QE can be increased to {approx}1.0% with atomic hydrogen cleaning. The surface charge limit at a very low current intensity and the clear dependence of the polarization on the surface charge limit are observed for the first time. On-going programs to develop photocathodes for the ILC and CLIC are briefly introduced.

• Research Organization: Stanford Linear Accelerator Center (SLAC)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 946449
• Report Number(s): SLAC-PUB-13514
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
43 PARTICLE ACCELERATORS
Accelerators
ACCPHY
BRIGHTNESS
CATHODES
CLEANING
ELECTRON BEAMS
ELECTRON SOURCES
ELECTRONS
HYDROGEN
LINEAR COLLIDERS
PHOTOCATHODES
POLARIZATION
STANFORD LINEAR ACCELERATOR CENTER
TEST FACILITIES