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arXiv · 1002.0493

The Orbital Period of Swift J1626.6-5156

A. Baykal·E. Gogus·S. C. Inam·T. Belloni
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Abstract

We present the discovery of the orbital period of Swift J1626.6-5156. Since its discovery in 2005, the source has been monitored with Rossi X-ray Timing Explorer, especially during the early stage of the outburst and into the X-ray modulating episode. Using a data span of $\sim$700 days, we obtain the orbital period of the system as 132.9 days. We find that the orbit is close to a circular shape with an eccentricity 0.08, that is one of the smallest among Be/X-ray binary systems. Moreover, we find that the timescale of the X-ray modulations varied, which led to earlier suggestions of orbital periods at about a third and half of the orbital period of Swift J1626.6-5156.

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A. Baykal, E. Gogus, S. C. Inam, T. Belloni. 2010-02-02. The Orbital Period of Swift J1626.6-5156. https://doi.org/10.1088/0004-637x%2F711%2F2%2F1306

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