The thermal-radiative wind in the neutron star low-mass X-ray binary GX 13?+?1
The thermal-radiative wind in the neutron star low-mass X-ray binary GX 13?+?1
复制标题
中子星低质量X射线双星GX 13中的热辐射风？
DOI：
10.1093/mnras/staa2254
复制
发表时间：
2020
影响因子：
4.8
通讯作者：
Takahashi Tadayuki
中科院分区：
文献类型：
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作者：
Tomaru Ryota;Done Chris;Ohsuga Ken;Odaka Hirokazu;Takahashi Tadayuki
我们将中子星双星 GX13 + 1 中观察到的高电离 X 射线吸收线与热辐射风的完整模拟相匹配。它使用与蒙特卡罗辐射传递耦合的辐射流体动力学代码来计算从氢和类氦铁和镍观察到的线剖面，包括所有强 K α 和 K β 跃迁。风非常强，因为这个物体有一个非常大的圆盘并且非常发光。由于离子柱较大，Fe K α 的吸收线强烈饱和，因此线等效宽度敏感地取决于速度结构。我们还模拟了包括方位角和径向速度水平上的各向同性湍流的线。我们将这些模型拟合到最高分辨率钱德拉三阶高能透射光栅光谱仪数据中看到的 Fexxvandxx 吸收线。这些数据已经排除了在径向速度~500 km s−1 水平上添加湍流的可能性。仅由热辐射风预测的速度结构与观测到的剖面相当吻合，在方位角速度水平上附加湍流的上限为~100 km s−1。这对磁加速度的任何剩余贡献给出了严格的限制。
We fit the observed high-ionization X-ray absorption lines in the neutron star binary GX13 + 1 with a full simulation of a thermal-radiative wind. This uses a radiation hydrodynamic code coupled to Monte Carlo radiation transfer to compute the observed line profiles from hydrogen and helium-like iron and nickel, including all strong K α and K β transitions. The wind is very strong as this object has a very large disc and is very luminous. The absorption lines from Fe K α are strongly saturated as the ion columns are large, so the line equivalent widths depend sensitively on the velocity structure. We additionally simulate the lines including isotropic turbulence at the level of the azimuthal and radial velocities. We fit these models to the Fexxvandxxviabsorption lines seen in the highest resolution Chandra third-order high-energy transmission grating spectrometer data. These data already rule out the addition of turbulence at the level of the radial velocity of ∼500 km s−1. The velocity structure predicted by the thermal-radiative wind alone is a fairly good match to the observed profile, with an upper limit to additional turbulence at the level of the azimuthal velocity of ∼100 km s−1. This gives stringent constraints on any remaining contribution from magnetic acceleration.