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arXiv · 2104.06453

Properties of Faint X-ray Activity of XTE J1908+094 in 2019

Debjit Chatterjee·Arghajit Jana·Kaushik Chatterjee·Riya Bhowmick·Sujoy Kumar Nath·Sandip K. Chakrabarti·A. Mangalam·Dipak Debnath
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Abstract

We study the properties of the faint X-ray activity of Galactic transient black hole candidate XTE~J1908+094 during its 2019 outburst. Here, we report the results of detailed spectral and temporal analysis during this outburst using observations from {\it Nuclear Spectroscopic Telescope Array (NuSTAR)}. We have not observed any quasi-periodic-oscillations (QPOs) in the power density spectrum (PDS). The spectral study suggests that the source remained in the softer (more precisely in soft-intermediate) spectral state during this short period of the X-ray activity. We notice a faint but broad Fe K$\alpha$ emission line at around 6.5 keV. We also estimate the probable mass of the black hole to be $6.5^{+0.5}_{-0.7}~M_\odot$ with 90\% confidence.

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Debjit Chatterjee, Arghajit Jana, Kaushik Chatterjee, Riya Bhowmick, Sujoy Kumar Nath, Sandip K. Chakrabarti, A. Mangalam, Dipak Debnath. 2021-04-13. Properties of Faint X-ray Activity of XTE J1908+094 in 2019. https://doi.org/10.3390/galaxies9020025

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