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arXiv · 1811.04341

Constraining the mass of the black hole GX 339-4 using spectro-temporal analysis of multiple outbursts

Sreehari H.·Nirmal Iyer·Radhika D.·Anuj Nandi·Samir Mandal
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Abstract

We carried out spectro-temporal analysis of the archived data from multiple outbursts spanning over the last two decades from the black hole X-ray binary GX 339-4. In this paper, the mass of the compact object in the X-ray binary system GX 339-4 is constrained based on three indirect methods. The first method uses broadband spectral modelling with a two component flow structure of the accretion around the black hole. The broadband data are obtained from {\it RXTE (Rossi X-ray Timing Explorer)} in the range 3.0 to 150.0 keV and from {\it Swift} and {\it NuSTAR (Nuclear Spectroscopic Telescope Array)} simultaneously in the range 0.5 to 79.0 keV. In the second method, we model the time evolution of Quasi-periodic Oscillation (QPO) frequencies, considering it to be the result of an oscillating shock that radially propagates towards or away from the compact object. The third method is based on scaling a mass dependent parameter from an empirical model of the photon index ($\Gamma$) - QPO ($\nu$) correlation. We compare the results at 90 percent confidence from the three methods and summarize the mass estimate of the central object to be in the range $8.28 - 11.89~ M_{\odot}$.

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Sreehari H., Nirmal Iyer, Radhika D., Anuj Nandi, Samir Mandal. 2018-11-11. Constraining the mass of the black hole GX 339-4 using spectro-temporal analysis of multiple outbursts. https://doi.org/10.1016/j.asr.2018.10.042

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