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J.C. Weingartner, D.K. Barr (George Mason University), B.T. Draine (Princeton University)
We model the photoelectric emission from dust exposed to extreme ultraviolet and X-ray radiation. We estimate the photoelectric yield for electrons ejected from the band structure of silicate and carbonaceous grains and also treat inner shell, Auger, and secondary electron emission. The latter emission mechanisms play a minor role in grain charging, compared with emission from the band structure, for environments where photoemission dominates over secondary emission induced by incident gas-phase electrons and ions (e.g., planetary nebulae). As an application of the model, we estimate grain charges in quasar outflows, where large grain potentials may provide some protection against destruction by sputtering. We acknowledge support from NASA.
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Bulletin of the American Astronomical Society, 37 #4
© 2005. The American Astronomical Soceity.