Status of high polarization DC high voltage Gallium Arsenide photoelectron guns

Users receive very high beam polarization from reliable GaAs photoelectron guns at facilities worldwide. Satisfaction with beam quality (and a number of lab closures) has reduced the level of polarized source R and D from the heyday of 1990s. However, new experiments and new accelerators proposals including high current unpolarized machines, require GaAs photoguns with capabilities that exceed today's state of the art. This submission describes the capabilities of today's high-polarization DC high voltage GaAs photoguns and discusses issues that must be addressed to meet new demands.