X-ray line emission from a fragmented stellar wind

Abstract

We discuss X-ray line formation in dense O star winds. A random distribution of wind shocks is assumed to emit X-rays that are partially absorbed by cooler wind gas. The cool gas resides in highly compressed fragments oriented perpendicular to the radial flow direction. For fully opaque fragments, we find that the blueshifted part of X-ray line profiles remains flat-topped even after severe wind attenuation, whereas the red part shows a steep decline. These box-type, blueshifted profiles resemble recent Chandra observations of the O3 star zeta Pup. For partially transparent fragments, the emission lines become similar to those from a homogeneous wind.

8 pages, 7 figures, Latex, to be published in A&A

References in corpus (3)

• Chandra Discovers a Very High Density X-ray Plasma on the O-Star Zeta Orionis
• Detection of Doppler Shifted X-ray Line Profiles from the Wind of Zeta Puppis (O4f)
• X-Ray Line Profiles from Parameterized Emission Within an Accelerating Stellar Wind

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