Observation of a Charge Limit for Photocathode Electron Guns
نویسندگان
چکیده
The Photocathode Electron Gun (PEG) at SLAC is required to produce bunch intensities of up to 10 electrons within 2 ns (8 Amps). Operation of PEG has demonstrated a ‘Charge Limit’ phenomenon, whereby the charge that can be extracted from the gun with an intense laser beam saturates at significantly less than 10 electrons (the expected ‘Space Charge Limited’ charge) when the photocathode Quantum Efficiency is low. We report studies of this Charge Limit phenomenon observed with a GaAs photocathode.
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