Spatial Distribution of Electron Stimulated Electron Desorption from a Metal Surface

Electron stimulated electron desorption yielding secondary electron emission is to be examined both experimentally and computationally. A novel secondary electron emission test stand at UNLV housing a particle position detector maps the evolution of the spatial distribution of electron beam stimulated secondary electrons emitted from a metal target. Electrons emitted from the target in the drift free region with initial momentum within an approximate 3deg<thetas<40deg conical angle of acceptance relative to the primary beam axis are collected and recorded. This allows for transient surface conditioning and degrading studies on a single pulse basis and a multi-pulse basis over time. In this preliminary study, an approximate analysis of the secondary electron emission test stand is provided with special considerations given to the detector assembly (e.g., grid, micro-channel plate, and particle position detector) and data acquisition electronics. Spatial distribution tendencies and total secondary electron emission counts are provided for a single target under test. The MAGIC modeling tool is employed to study the secondary electron emission process. Comparisons will be made with experiment.