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arXiv · 1005.0709

The Swift-BAT hard X-ray sky monitoring unveils the orbital period of the HMXB IGR J16493-4348

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

IGR J16493-4348 is a supergiant high mass X-ray binary discovered by INTEGRAL in 2004. The source is detected at a significance level of $\sim21$ standard deviations in the Swift-BAT survey data collected during the first 54 months of the Swift mission. The timing analysis reveals an orbital period of $\sim$6.78 days and the presence of a full eclipse of the compact ob\ ject. The dynamical range (variability up to a factor $\sim$20) observed during the BAT monitoring suggests that IGR J16493-4348 is a wind-fed system. The derived semi-major axis of the binary system is $\sim55 R_{\sun}$ with an orbit eccentr\ icity lower than 0.15.

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G. Cusumano, V. La Parola, P. Romano, A. Segreto, S. Vercellone, G. Chincarini. 2010-05-05. The Swift-BAT hard X-ray sky monitoring unveils the orbital period of the HMXB IGR J16493-4348. https://doi.org/10.1111/j.1745-3933.2010.00872.x

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