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تسجيل مستخدم جديدThe outburst of the X-ray nova GRS 1739-278 in September, 2016
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I.A. Mereminskiy
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During the scanning observations of the Galactic Center region in August - September 2016 we detected the new outburst of the historical X-ray nova GRS 1739-278, the black hole candidate LMXB system. In this letter we present results of INTEGRAL and Swift-XRT observations taken during the outburst. In hard X-ray band (20-60 keV) the flux from the source raised from $sim$11 to $sim$30 mCrab between 3 and 14 of September. For nearly 8 days the source has been observed at this flux level and then faded to $sim$15 mCrab. The broadband quasi-simultaneous spectrum obtained during the outburst is well described by the absorbed powerlaw with the photon index $Gamma=1.86pm0.07$ in broad energy range 0.5-150 keV, with absorption corresponding to ${N_{H}}=2.3times10^{22}$ cm$^{-2}$ assuming solar abundance. Based on this we can conclude that the source was in the low/hard state. From the lightcurve and spectra we propose that this outburst was `failed, i.e. amount of accreted matter was not sufficient to achieve the high/soft spectral state with dominant soft blackbody component as seen in normal outbursts of black hole candidates.
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