Discovery of the 51.47-d orbital period in the supergiant fast X-ray transient XTE J1739-302 with INTEGRAL
Hill, A. B.; Bird, A. J.; Scaringi, S.; McBride, V. A.; Bazzano, A.; Clark, D. J.; Sguera, V.; Drave, S. P.
United Kingdom, France, Italy, Netherlands
Abstract
Timing analysis of ∼12.4 Ms of INTEGRAL/IBIS data has revealed a period of 51.47 ± 0.02 d in the supergiant fast X-ray transient source XTE J1739-302/IGR J17391-3021 that can be interpreted as an orbital period. An outburst history showing 35 epochs of activity has been produced, showing X-ray outbursts throughout the orbit of XTE J1739-302. Possible indications of an enhanced equatorial density region within the supergiant stellar wind are present in the phase-folded light curve. It is found that many orbital configurations are possible within this system with eccentricities of up to e∼ 0.8.