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arXiv · 1711.01753

Gamma-rays from the binary system containing PSR J2032+4127 during its periastron passage

Wlodek Bednarek·Piotr Banasinski·Julian Sitarek
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Abstract

The energetic pulsar, PSR J2032+4127, has been recently discovered in the direction of the unidentified HEGRA TeV gamma-ray source (TeV J2032+4130). It is proposed that this pulsar forms a binary system with the Be type star, MT91 213, expected to reach the periastron late in 2017. We performed detailed calculations of the gamma-ray emission produced close to the binary system's periastron passage by applying a simple geometrical model. Electrons accelerated at the collision region of pulsar and stellar winds initiate anisotropic Inverse Compton electron-positron pair cascades by scattering soft radiation from the massive companion. The gamma-ray spectra, from such a comptonization process, are confronted with the measurements of the extended TeV gamma-ray emission from the HEGRA TeV gamma-ray source. We discuss conditions within the binary system, at the periastron passage of the pulsar, for which the gamma-ray emission from the binary can overcome the extended, steady TeV gamma-ray emission from the HEGRA TeV gamma-ray source.

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Wlodek Bednarek, Piotr Banasinski, Julian Sitarek. 2017-11-06. Gamma-rays from the binary system containing PSR J2032+4127 during its periastron passage. https://doi.org/10.1088/1361-6471%2Faa97ee

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