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arXiv · 1005.0684

Detection of an orbital period in the supergiant high mass X-ray binary IGR J16465$-$4507 with Swift-BAT

V. La Parola·G. Cusumano·P. Romano·A. Segreto·S. Vercellone·G. Chincarini
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Abstract

We analysed the IGR J16465-4507 Burst Alert Teelescope survey data collected during the first 54 months of the Swift mission. The source is in a crowded field and it is revealed through an ad hoc imaging analysis at a significance level of ~14 standard deviations. The 15-50 keV average flux is ~3E-11 erg/cm^2/s. The timing analysis reveals an orbital period of 30.243 +/- 0.035 days. The folded light curve shows the presence of a wide phase interval of minimum intensity, lasting ~20% of the orbital period. This could be explained with a full eclipse of the compact object in an extremely eccentric orbit or with the passage of the compact source through a lower density wind at the orbit apastron. The modest dynamical range observed during the BAT monitoring suggests that IGR J16465-4507 is a wind-fed system, continuously accreting from a rather homogeneous wind, and not a member of the Supergiant Fast X-ray Transient class.

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V. La Parola, G. Cusumano, P. Romano, A. Segreto, S. Vercellone, G. Chincarini. 2010-05-05. Detection of an orbital period in the supergiant high mass X-ray binary IGR J16465$-$4507 with Swift-BAT. https://doi.org/10.1111/j.1745-3933.2010.00860.x

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