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arXiv · astro-ph/0107411

Variable gamma-ray emission from the Be/X-ray transient A0535+26?

Gustavo E. Romero·M. M. Kaufman Bernado·Jorge A. Combi·Diego F. Torres
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Abstract

We present a study of the unidentified gamma-ray source 3EG J0542+2610. This source is spatially superposed to the supernova remnant G180.0-1.7, but its time variability makes unlikely a physical link. We have searched into the EGRET location error box for compact radio sources that could be the low energy counterpart of the gamma-ray source. Although 29 point-like radio sources were detected and measured, none of them is strong enough as to be considered the counterpart of a background gamma-ray emitting AGN. We suggest that the only object within the 95 % error box capable of producing the required gamma-ray flux is the X-ray transient A0535+26. We show that this Be/accreting pulsar can produce variable hadronic gamma-ray emission through the mechanism originally proposed by Cheng & Ruderman (1989), where a proton beam accelerated in a magnetospheric electrostatic gap impacts the transient accretion disk.

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Gustavo E. Romero, M. M. Kaufman Bernado, Jorge A. Combi, Diego F. Torres. 2001-07-20. Variable gamma-ray emission from the Be/X-ray transient A0535+26?. https://doi.org/10.1051/0004-6361%3A20011044

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