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.
@article{arxiv.1202.3164,
title = {Periodic Emission from the Gamma-ray Binary 1FGL J1018.6-5856},
author = {The Fermi LAT Collaboration and M. J. Coe and F. Di Mille and P. G. Edwards and M. D. Filipović and J. L. Payne and J. Stevens and M. A. P. Torres},
journal= {arXiv preprint arXiv:1202.3164},
year = {2012}
}
Comments
Contact authors: R.H.D. Corbet, M. Kerr, C.C. Cheung