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arXiv · 1505.02529

Determination of mass of IGR J17091-3624 from "Spectro-Temporal" variations during onset-phase of the 2011 outburst

N. Iyer·A. Nandi·S. Mandal
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Abstract

The 2011 outburst of the black hole candidate IGR J17091-3624 followed the canonical track of state transitions along with the evolution of Quasi-Periodic Oscillation (QPO) frequencies before it began exhibiting various variability classes similar to GRS 1915+105. We use this canonical evolution of spectral and temporal properties to determine the mass of IGR J17091-3624, using three different methods, viz : Photon Index ($Γ$) - QPO frequency ($ν$) correlation, QPO frequency ($ν$) - Time (day) evolution and broadband spectral modelling based on Two Component Advective Flow. We provide a combined mass estimate for the source using a Naive Bayes based joint likelihood approach. This gives a probable mass range of 11.8 M$_{\odot}$ - 13.7 M$_{\odot}$. Considering each individual estimate and taking the lowermost and uppermost bounds among all three methods, we get a mass range of 8.7 M$_{\odot}$ - 15.6 M$_{\odot}$ with 90% confidence. We discuss the probable implications of our findings in the context of two component accretion flow.

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N. Iyer, A. Nandi, S. Mandal. 2015-05-11. Determination of mass of IGR J17091-3624 from "Spectro-Temporal" variations during onset-phase of the 2011 outburst. https://doi.org/10.1088/0004-637x%2F807%2F1%2F108

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