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arXiv · 1405.5533

1FGL J0523.5-2529: A New Probable Gamma-ray Pulsar Binary

Jay Strader·Laura Chomiuk·Eda Sonbas·Kirill Sokolovsky·David J. Sand·Alexander S. Moskvitin·C. C. Cheung
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Abstract

We report optical photometric and SOAR spectroscopic observations of an X-ray source found within the localization error of the Fermi-LAT unidentified gamma-ray source J0523.5-2529. The optical data show periodic flux modulation and radial velocity variations indicative of a binary with a 16.5-hr period. The data suggest a massive non-degenerate secondary (~> 0.8 M_sun), and we argue the source is likely a pulsar binary. The radial velocities have good phase coverage and show evidence for a measurable eccentricity (e=0.04). There is no clear sign of irradiation of the secondary in either photometry or spectroscopy. The spatial location out of the Galactic plane and gamma-ray luminosity of the source are more consistent with classification as a recycled millisecond pulsar than as a young pulsar. Future radio timing observations can confirm the identity of the primary and further characterize this interesting system.

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Jay Strader, Laura Chomiuk, Eda Sonbas, Kirill Sokolovsky, David J. Sand, Alexander S. Moskvitin, C. C. Cheung. 2014-05-28. 1FGL J0523.5-2529: A New Probable Gamma-ray Pulsar Binary. https://doi.org/10.1088/2041-8205%2F788%2F2%2Fl27

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