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arXiv · 1606.08520

A Possible 55-day X-ray Period of the Ultraluminous Accreting Pulsar M82 X-2

A. K. H. Kong·C. -P. Hu·L. C. -C. Lin·K. L. Li·R. Jin·C. Y. Liu·D. C. -C. Yen
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Abstract

We report a possible detection of a 55-day X-ray modulation for the ultraluminous accreting pulsar M82 X-2 from archival Chandra observations. Because M82 X-2 is known to have a 2.5-day orbital period, if the 55-day period is real, it will be the superorbital period of the system. We also investigated variabilities of other three nearby ultraluminous X-ray sources in the central region of M82 with the Chandra data and did not find any evidence of periodicities. Furthermore, we re-examined the previously reported 62-day periodicity near the central region of M82 by performing a systematic timing study with all the archival Rossi X-Ray Timing Explorer and Swift data. Using various dynamic timing analysis methods, we confirmed that the 62-day period is not stable, suggesting that it is not the orbital period of M82 X-1 in agreement with previous work.

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A. K. H. Kong, C. -P. Hu, L. C. -C. Lin, K. L. Li, R. Jin, C. Y. Liu, D. C. -C. Yen. 2016-06-28. A Possible 55-day X-ray Period of the Ultraluminous Accreting Pulsar M82 X-2. https://doi.org/10.1093/mnras%2Fstw1558

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