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Discovery of very high energy gamma-rays associated with an X-ray binary

H. E. S. S. Collaboration·:·F. Aharonian
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Abstract

X-ray binaries are composed of a normal star in orbit around a neutron star or stellar-mass black hole. Radio and X-ray observations have led to the presumption that some X-ray binaries called microquasars behave as scaled down active galactic nuclei. Microquasars have resolved radio emission that is thought to arise from a relativistic outflow akin to active galactic nuclei jets, in which particles can be accelerated to large energies. Very high energy gamma-rays produced by the interactions of these particles have been observed from several active galactic nuclei. Using the High Energy Stereoscopic System, we find evidence for gamma-ray emission >100 GeV from a candidate microquasar, LS 5039, showing that particles are also accelerated to very high energies in these systems.

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H. E. S. S. Collaboration, :, F. Aharonian. 2005-08-12. Discovery of very high energy gamma-rays associated with an X-ray binary. https://doi.org/10.1126/science.1113764

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