X-ray Emission Line Prole Modeling of O Stars: Fitting a Spherically-Symmetric Analytic Wind-Shock Model to the Chandra Spectrum of Puppis

X-ray emission line proles provide the most direct insight into the dynamics and spatial distribution of the hot, X-ray-emitting plasma above the surfaces of OB stars. The O supergiant Puppis shows broad, blueshifted, and asymmetric line proles, generally consistent with the wind-shock picture of OB star X-ray production. We model the proles of eight lines in the Chandra HETGS spec-trum of this prototypical hot star. The tted lines indicate that the plasma is distributed throughout the wind starting close to the photosphere, that there is signi cantly less attenuation of the X-rays by the overlying wind than is gen-erally supposed, and that there is not a strong trend in wind absorption with wavelength