A High-intensity Highly-polarized Electron Beam for High-energy Physics*
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چکیده
A new high-energy parity violation (PV) experiment at SLAC as well as particle-physics experiments using future ee colliders (such as NLC) operating at energies above the scale of unification of the electromagnetic and weak interactions require a highly-polarized electron beam with intensities previously unachievable due to a surface charge limit (SCL) effect at the cathode of the polarized electron source. A newly developed photocathode which allows these high intensities is being used for the SLAC PV experiment E-158. The intensity stability required for stable machine operation is determined by the source laser stability, which has been reduced to 0.5%. Temporal pulse shaping is performed on the laser beam using an improved pulse shaper. Details of the beam generation, energy compensation, and linac performance recently achieved for the SLAC parity violation experiment E-158 are discussed.
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تاریخ انتشار 2002