Ponente
Descripción
Liquid argon and liquid xenon detectors often encounter high voltage issues at much smaller fields than the theoretical breakdown limit. Minor electron emission events from high voltage electrodes are often sufficient to produce unacceptable deadimes, backgrounds to the physics to be investigated, and may even be harbingers of impending breakdown. These problems become more acute as the size of detectors increases, increasing the drift length, and hence the potential and stressed area for a given drift field.
This talk will outline experiments at the Stanford liquid xenon lab exploring high voltage phenomena preceding breakdown. Unlike previous work, the emphasis here is on the surface chemistry of the electrodes, that are mechanically polished to limit effects that may be caused by mechanical asperities. With field capabilities up to 60 kV/cm over 15 cm^2 electrode surface areas, a comparison is made between the high voltage performance of polished stainless steel versus those further coated in various ways.
