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تسجيل مستخدم جديدPolarized Photocathodes Make the Grade
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Future linear colliders will require high levels of performance from their electron sources. A group at SLAC has recently tested a structure that substantially exceeds current collider polarized electron source pulse-profile requirements.
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Future colliders such as NLC and JLC will require a highly-polarized macropulse with charge that is more than an order of magnitude beyond that which could be produced for the SLC. The maximum charge from the SLC uniformly-doped GaAs photocathode was
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r, high repetition rate, laser systems. We have observed an emission of electrons for photon energy below the work function of the material. This is explained by multiple photon absorption at the photocathode. We have not observed any degradation of the QE for those materials, but an improvement when irradiating them over a long period of time. This is contrary to observations made in RF photoguns.
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This paper discusses the behavior of electron bunch charge produced in an L-band normal conducting radio frequency cavity (RF gun) from Cs2Te photocathodes illuminated with ps-long UV laser pulses when the laser transverse distribution consists of a
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Future colliders that require low-emittance highly-polarized electron beams are the main motivation for developing a polarized rf gun. However there are both technical and physics issues in generating highly polarized electron beams using rf guns tha
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