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P V and the Mass Loss Discrepancy in O Stars

D. Massa·A. W. Fullerton·R. K. Prinja
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Abstract

Building upon a previous analysis of P V wind lines in LMC O stars, we analyze the P V wind lines in a sample of Galactic O stars which have empirical mass loss rates determined from either their radio fluxes or H alpha profiles. Since the wind analysis provides a measure of \dot{M}q where q is the ionization fraction of the ion, we determine q(P V) observationally. In spite of model predictions that q should be about 1 for mid-O stars, we find q(P V) is less than 0.15 throughout the O stars. We discuss the origin of this discrepancy.

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D. Massa, A. W. Fullerton, R. K. Prinja. 2004-10-04. P V and the Mass Loss Discrepancy in O Stars. https://arxiv.org/abs/astro-ph/0410089

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