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arXiv · 1202.3164

Periodic Emission from the Gamma-ray Binary 1FGL J1018.6-5856

The Fermi LAT Collaboration·M. J. Coe·F. Di Mille·P. G. Edwards·M. D. Filipović·J. L. Payne·J. Stevens·M. A. P. Torres
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Abstract

Gamma-ray binaries are stellar systems containing a neutron star or black hole with gamma-ray emission produced by an interaction between the components. These systems are rare, even though binary evolution models predict dozens in our Galaxy. A search for gamma-ray binaries with the Fermi Large Area Telescope (LAT) shows that 1FGL J1018.6-5856 exhibits intensity and spectral modulation with a 16.6 day period. We identified a variable X-ray counterpart, which shows a sharp maximum coinciding with maximum gamma-ray emission, as well as an O6V((f)) star optical counterpart and a radio counterpart that is also apparently modulated on the orbital period. 1FGL J1018.6-5856 is thus a gamma-ray binary, and its detection suggests the presence of other fainter binaries in the Galaxy.

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The Fermi LAT Collaboration, M. J. Coe, F. Di Mille, P. G. Edwards, M. D. Filipović, J. L. Payne, J. Stevens, M. A. P. Torres. 2012-02-14. Periodic Emission from the Gamma-ray Binary 1FGL J1018.6-5856. https://doi.org/10.1126/science.1213974

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