Discovery of an Iron K Absorption Line in the Low-Mass X-Ray Binary GX 13+1
Discovery of an Iron K Absorption Line in the Low-Mass X-Ray Binary GX 13+1
复制标题
低质量 X 射线双星 GX 13 1 中铁 K 吸收线的发现
DOI：
10.1086/323007
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
H. Inoue
中科院分区：
文献类型：
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作者：
Y. Ueda;K. Asai;K. Yamaoka;T. Dotani;H. Inoue
我们报道在低质量x射线双星GX 13+1的光谱中发现了具有ASCA的铁K吸收谱线特征。吸收谱线在7.0 keV处被检测到，等效宽度为35±8 eV，这是由于Kα谱线被视线内柱密度大于~1018 cm-2的Fe XXVI离子共振散射所致。从中子星双星中探测到这样的光谱特征，排除了它是银河系超光速射流源所特有的假设。从谱线参数与超光速源谱线参数的相似性来看，我们推测我们是通过吸积盘外部高度电离的等离子体以较高的倾角观测到x射线发射的。这张照片与这种等离子体在x射线双星中普遍存在的现象是一致的。
We report the discovery of an iron K absorption-line feature with ASCA in the spectra of the low-mass X-ray binary GX 13+1. The absorption line is detected at 7.0 keV with an equivalent width of 35 ± 8 eV, which is attributed to resonant scattering of the Kα line from Fe XXVI ions in the line of sight whose column density is larger than ~1018 cm-2. The detection of such a spectral feature from a neutron star binary rules out the hypothesis that it is unique to the Galactic superluminal jet sources. From the similarity of the line parameters to those of the superluminal sources, we infer that we view the X-ray emission through a highly ionized plasma in outer parts of the accretion disk with a relatively high inclination angle. This picture is consistent with the universal presence of such plasmas in X-ray binaries accreting through disks.