论文标题
V4641 SGR的高分辨率X射线光谱在其2020年爆发期间
High resolution X-ray spectroscopy of V4641 Sgr during its 2020 outburst
论文作者
论文摘要
我们观察到银河黑洞X射线二进制V4641 SGR，在源2020年爆发期间，Chandra上的高分辨率传输光栅。在两个时期的Chandra光栅观测上，我们看到了许多高度离子的金属线，并叠加在圆盘主导的X射线连续体上。测得的内圆盘温度和亮度意味着一个不可行的内盘半径，因此我们建议V4641 SGR的中央发动机被遮盖，并且我们正在查看散射的X射线。我们发现Chandra光谱中的发射线不能受到单个光电离的模型的约束，而是发现需要两个单独的光电离模型组件，一个用于再现铁线，另一个用于其他金属。我们将观察到的V4641 SGR的X射线光谱与源前爆发期间的光学研究进行了比较，这表明该线源于吸积盘风，可能具有球形几何形状。
We observed the Galactic black hole X-ray binary V4641 Sgr with the high resolution transmission gratings on Chandra during the source's 2020 outburst. Over two epochs of Chandra gratings observations, we see numerous highly ionized metal lines, superimposed on a hot, disc-dominated X-ray continuum. The measured inner disc temperatures and luminosities imply an unfeasibly small inner disc radius, such that we suggest that the central engine of V4641 Sgr is obscured, and we are viewing scattered X-rays. We find that the emission lines in the Chandra spectra cannot be constrained by a single photoionized model, instead finding that two separate photoionized model components are required, one to reproduce the iron lines and a second for the other metals. We compare the observed X-ray spectra of V4641 Sgr to optical studies during previous outbursts of the source, suggesting that the lines originate in an accretion disc wind, potentially with a spherical geometry.
