Investigation of photocathodes at a wavelength of 44 A

In this work the quantum efficiencies for the wavelength 44 A of some photocathodes are compared. The measured curves of the angular distribution of the emitted electrons can be fitted by a simple correction to a cosine distribution. The angular dependence of the quantum efficiency seems to be similar to that of the secondary emission coefficient which is proportional to 1/cos A for polycrystalline surfaces, where A is the angle of incidence.