论文标题
Swift J1728.9-3613是黑洞X射线二进制：光谱和计时研究使用NICE
Swift J1728.9-3613 is a black hole X-ray binary: spectral and timing study using NICER
论文作者
论文摘要
我们使用Neil Gehrels Swift天文台上的爆发警报望远镜（BAT）发现了新的银河X射线瞬态Swift J1728.9-3613的新银河X射线瞬态Swift J1728.9-3613的不同时序和光谱特性的不同时序和光谱特性。在爆发期间，源经过了多次向不同光谱状态的过渡，并且完整的演化在硬度强度图中创建了Q形轨道。在RMS强度图中还观察到了部分滞后，这是黑洞瞬变的另一个明确定义的现象。在SIMS中，功率密度光谱由宽带噪声组件支配，并检测到两种B型QPO。我们已经拟合了从爆发期间进行的更好的观察结果获得的1-10 keV能量光谱，并研究了光谱参数的时间演化。在MJD 58584.69上，发生了一个小规模的反射，我们观察到，光谱指数也降低到与其他光谱参数有限变化相关的较低的值，而1-10 KEV平均磁通量也增加了。我们观察到，在软状态期间，积聚盘的最内向半径几乎是恒定的，这对应于最内向的稳定圆形轨道（ISCO）。我们已经通过将1-10 keV较好的光谱与diskbb组件拟合，考虑到非旋转黑洞二进制系统的质量的下限约为4.6 m。当降压光度的光度为Eddington发光度的0.01倍时，就会发生柔软的过渡。基于我们对定时和光谱特性演变的结合研究，我们得出结论，新的源Swift J1728.9-3613是黑洞X射线二元。
We study different timing and spectral properties of the new Galactic X-ray transient Swift J1728.9-3613 using NICER and Swift, discovered by the Burst Alert Telescope (BAT) on the Neil Gehrels Swift Observatory. The source went through multiple transitions to different spectral states during the outburst, and the complete evolution created a q-shaped track in the hardness intensity diagram. A partial hysteresis is also observed in the RMS-intensity diagram, which is another well-defined phenomenon of black hole transients. In SIMS, power density spectra were dominated by broadband noise components, and two type B QPOs were detected. We have fitted 1-10 keV energy spectra obtained from NICER observations that were performed during the outburst, and the temporal evolution of spectral parameters were studied. On MJD 58584.69, a small-scale reflare happened, and we observed that the spectral index decreased to a much lower value associated with finite changes in other spectral parameters also, and the 1-10 keV averaged flux also increased. We observed that the innermost radius of the accretion disc was almost constant during the soft state, which corresponds to the Innermost Stable Circular Orbit (ISCO). We have measured the lower limit of mass of the compact object to be approximately 4.6 M, considering a non-spinning black hole binary system, by fitting 1-10 keV NICER spectra with the diskbb component. The soft-to-hard transition occurred when the bolometric luminosity was 0.01 times the Eddington luminosity. Based on our combined study of the evolution of the timing and spectral properties, we conclude that the new source Swift J1728.9-3613 is a black hole X-ray binary.
