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arXiv · 1708.00066

HESS J0632+057: hydrodynamics and nonthermal emission

Valentí Bosch-Ramon·Maxim V. Barkov·Andrea Mignone·Pol Bordas
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Abstract

HESS J0632+057 is an eccentric gamma-ray Be binary that produces non-thermal radio, X-rays, GeV, and very high-energy gamma rays. The non-thermal emission of HESS J0632+057 is modulated with the orbital period, with a dominant maximum before apastron passage. The nature of the compact object in HESS J0632+057 is not known, although it has been proposed to be a young pulsar as in PSR B1259-63, the only gamma-ray emitting high-mass binary known to host a non-accreting pulsar. In this Letter, we present hydrodynamical simulations of HESS J0632+057 in the context of a pulsar and a stellar wind interacting in an eccentric binary, and propose a scenario for the non-thermal phenomenology of the source. In this scenario, the non-thermal activity before and around apastron is linked to the accumulation of non-thermal particles in the vicinity of the binary, and the sudden drop of the emission before apastron is produced by the disruption of the two-wind interaction structure, allowing these particles to efficiently escape. In addition to providing a framework to explain the non-thermal phenomenology of the source, this scenario predicts extended, moving X-ray emitting structures similar to those observed in PSR B1259-63.

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Valentí Bosch-Ramon, Maxim V. Barkov, Andrea Mignone, Pol Bordas. 2017-07-31. HESS J0632+057: hydrodynamics and nonthermal emission. https://doi.org/10.1093/mnrasl%2Fslx124

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