Modelling X-ray variability in the structured atmospheres of hot stars

Abstract

We describe X-ray production in the atmospheres of hot, early-type stars in the framework of a ``stochastic shock model''. The extended envelope of a star is assumed to possess numerous X-ray emitting ``hot'' zones that are produced by shocks and embedded in the ambient ``cold'' medium in dynamical equilibrium. It is shown that the apparent lack of X-ray variability on short (order of hours) timescales do not contradict a shock model for X-ray production. The character of the X-ray variability is found to depend on the frequency with which hot zones are generated, the cool wind opacity to X-rays, and the wind flow parameters, such as mass loss rate and terminal speed.

arXiv comment11 pages, 6 figures, to be published in Astronomy and Astrophysics

References in corpus (4)

• High resolution X-Ray spectroscopy of Zeta Puppis with the XMM-Newton Reflection Grating Spectrometer
• A Simple Scaling Analysis of X-ray Emission and Absorption in Hot-Star Winds
• X-ray Line Emission from the Hot Stellar Wind of theta 1 Ori C
• Profile Shapes for Optically Thick X-ray Emission Lines from Stellar Winds

Cited by in corpus (9)

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• A detailed X-ray investigation of zeta Puppis - The variability on short and long timescales
• Modeling broadband X-ray absorption of massive star winds
• The Effects of Clumps in Explaining X-ray Emission Lines from Hot Stars
• The X-ray emission of Be+stripped star binaries
• The XMM-Newton EPIC X-ray Light Curve Analysis of WR 6
• A Multi-Phase Suzaku Study of X-rays from tau Sco
• On X-ray pulsations in beta Cephei-type variables
• Recombination Lines and Free-Free Continua formed in Asymptotic Ionized Winds: Analytic solution for the radiative transfer