ﻻ يوجد ملخص باللغة العربية
AT2019wey is a new galactic X-ray binary that was first discovered as an optical transient by the Australia Telescope Large Area Survey (ATLAS) on December 7, 2019. AT2019wey consists of a black hole candidate as well as a low-mass companion star ($M_{text {star }} lesssim 0.8 M_{odot}$) and is likely to have a short orbital period ($P_{text {orb }} lesssim 8$ h). Although AT2019wey began activation in the X-ray band during almost the entire outburst on March 8, 2020, it did not enter the soft state during the entire outburst. In this study, we present a detailed spectral analysis of AT2019wey in the low/hard state during its X-ray outburst on the basis of Nuclear Spectroscopic Telescope Array emph observations. We obtain tight constraints on several of its important physical parameters by applying the State-of-art texttt{relxill} relativistic reflection model family. In particular, we determine that the measured inner radius of the accretion disk is most likely to have extended to the innermost stable circular orbit (ISCO) radius, i.e., $R_{text{in}}=1.38^{+0.23}_{-0.16}~R_{text{ISCO}}$. Hence, assuming $R_{text{in}}$=$R_{text{ISCO}}$, we find the spin of AT2019wey to be $a_{*}sim$ $0.97$, which is close to the extreme and an inner disk inclination angle of ~$isim$ $22 ^{circ}$. Additionally, according to our adopted models, AT2019wey tends to have a relatively high iron abundance of $A_{mathrm{Fe}}sim$ 5 $A_{mathrm{Fe}, odot}$ and a high disk ionization state of $log xisim$ 3.4.
AT2019wey (SRGA J043520.9+552226, SRGE J043523.3+552234) is a transient first reported by the ATLAS optical survey in 2019 December. It rose to prominence upon detection, three months later, by the Spektrum-Roentgen-Gamma (SRG) mission in its first a
We report on a NuSTAR observation of the recently discovered bright black hole candidate MAXI J1535-571. NuSTAR observed the source on MJD 58003 (five days after the outburst was reported). The spectrum is characteristic of a black hole binary in the
We present results from the Nuclear Spectroscopic Telescope Array (NuSTAR) observations of the new black hole X-ray binary candidate MAXI J1631-479 at two epochs during its 2018-2019 outburst, which caught the source in a disk dominant state and a po
AT2019wey is a Galactic low mass X-ray binary with a candidate black hole accretor first discovered as an optical transient by ATLAS in December 2019. It was then associated with an X-ray source discovered by SRG in March 2020. After observing a brig
We present a spectral and timing analysis of the newly reported Galactic X-ray transient Swift J1658.2-4242 observed by NuSTAR and Swift. The broad-band X-ray continuum is typical of a black hole binary in the bright hard state, with a photon index o