Development, operation and analysis of bialkali antimonide photocathodes for high-brightness photo-injectors

Different methods for the preparation of K-Cs-Sb photocathodes, suitable for electron sources in RF guns, are described in detail. The resulting material has been characterized by Auger depth profiling technique, and by its spectral response in the 250-600 nm range, as well. The results of lifetime experiments under operational and `'laboratory'' conditions are presented. The role of CO2 in reducing the operational lifetime of the photocathodes and that of O-2 in improving the long-wavelength response are investigated.