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arXiv · 1007.2272

Variability in the orbital profiles of the X-ray emission of the gamma-ray binary LS I +61 303

Diego F. Torres·Shu Zhang·Jian Li·Nanda Rea·G. Andrea Caliandro·Daniela Hadasch·Yupeng Chen·Jianmin Wang·Paul S. Ray
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Abstract

We report on the analysis of Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA) monitoring observations of the $γ$-ray binary system LS I +61 303, covering 35 full cycles of its orbital motion. This constitutes the largest continuous X-ray monitoring dataset analyzed to date for this source. Such an extended analysis allows us to report: a) the discovery of variability in the orbital profiles of the X- ray emission, b) the existence of a few (recent) short flares on top of the overall behavior typical of the source, which, given the PCA field-of-view, may or may not be associated with LS I +61 303, and c) the determination of the orbital periodicity using soft X-ray data alone.

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Diego F. Torres, Shu Zhang, Jian Li, Nanda Rea, G. Andrea Caliandro, Daniela Hadasch, Yupeng Chen, Jianmin Wang, Paul S. Ray. 2010-07-14. Variability in the orbital profiles of the X-ray emission of the gamma-ray binary LS I +61 303. https://doi.org/10.1088/2041-8205%2F719%2F1%2Fl104

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