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Non-thermal X-ray and Gamma-ray Emission from the Colliding Wind Binary WR140

J. M. Pittard·S. M. Dougherty
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Abstract

WR140 is the archetype long-period colliding wind binary (CWB) system, and is well known for dramatic variations in its synchrotron emission during its 7.9-yr, highly eccentric orbit. This emission is thought to arise from relativistic electrons accelerated at the global shocks bounding the wind-collision region (WCR). The presence of non-thermal electrons and ions should also give rise to X-ray and gamma-ray emission from several separate mechanisms, including inverse-Compton cooling, relativistic bremsstrahlung, and pion decay. We describe new calculations of this emission and make some preliminary predictions for the new generation of gamma-ray observatories. We determine that WR140 will likely require several Megaseconds of observation before detection with INTEGRAL, but should be a reasonably strong source for GLAST.

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J. M. Pittard, S. M. Dougherty. 2005-09-30. Non-thermal X-ray and Gamma-ray Emission from the Colliding Wind Binary WR140. https://arxiv.org/abs/astro-ph/0509896

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