G0 Beam
• Requires unusual time structure: 31 MHz (32
nsec between pulses)
(1/16 of usual CEBAF time structure of 499 MHz (2 nsec between
pulses)
• Required new Ti:Sapphire laser
in polarized electron gun
• Higher charge per bunch ® space charge effects complicated
beam transport in injector (challenging beam optics
problem)
• Beam quality closest to
operating specs during Jan. 2003 delivery
• Beam current 40 mA
• Beam fluctuations at (30 Hz/4) ~ DX, DY < 20 mm DI/I < 2000 ppm
• Ongoing Beam Work
• multiple Hall delivery
• beam position feedback
CEBAF polarized injector