Barday, R.; Kamps, T.; Kugeler, O.; Neumann, A.; Schmeißer, M.; Völker, J.; Sekutowicz, J.; Nietubyc, R.; Smedley, J.; Kneisel, P.: Characterization of a Superconducting Pb Photocathode in a SRF Gun Cavity. In: Proceedings of 4th International Particle Accelerator Conference, IPAC 2013, May 13-17, 2013, Shanghai, China. , 2013. - ISBN 978-3-95450-122-9, p. 279-281
http://accelconf.web.cern.ch/AccelConf/IPAC2013/papers/mopfi001.pdf
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Abstract:
Photocathodes are a limiting factor for the next generation of ultra-high brightness photoinjector driven accelerators. We studied the behavior of a superconducting Pb cathode in the cryogenic environment of a superconducting rf gun cavity related to the quantum efficiency, its spatial distribution and the work function. Cathode surface contaminations can modify the performance of the photocathodes as well as the gun cavity. We discuss the possibilities to remove these contaminations.