论文标题
X射线辐照HMXB的恒星风与B Supergiants：对ULX的影响
X-ray irradiation of the stellar wind in HMXBs with B supergiants: Implications for ULXs
论文作者
论文摘要
风馈高质量的X射线二进制物是由紧凑型恒星上的辐射驱动风积聚的。积聚生成的X射线改变了风的电离状态。由于较高的电离状态驱动风的有效性降低，因此X射线电离可能会制动风的加速。这会导致风端速度的下降和朝向X射线源方向的质量通量。我们研究X射线离子化对B超级恒星风的影响。我们确定X射线照射会显着影响恒星风的二元参数。可以在绘制光学深度参数与X射线光度的图表中进行研究。对于低光学深度或高X射线照明性，X射线电离导致瞄准X射线源的风中断。带有B-苏植物组件的高质量X射线二进制组的观察参数出现在风中断区域之外。 X射线反馈确定所得的X射线光度。对于低X射线亮度，电离弱，并且在较大速度下的X射线和流动不会破坏风，因此积聚速率相对较低。另一方面，对于高X射线亮度，X射线电离破坏了流动制动加速度，风速较低，积聚速率变高。这些效果决定了单个二进制文件的X射线光度。考虑到X射线反馈，估计的X射线发光度合理地与观察值一致。我们研究了小规模风不均匀性的影响，表明它们通过增加重组和质量损失来削弱X射线电离的影响。这种效果在双重性跳跃区域尤为重要。我们表明，具有$ l_x <10^{40} $ erg/s的超湿X射线二进制文件可能是通过在巨大的黑洞上积聚B-Supergiant风的供电。
Wind-fed high-mass X-ray binaries are powered by accretion of the radiatively driven wind on the compact star. Accretion-generated X-rays alter the ionization state of the wind. Because higher ionization states drive the wind less effectively, X-ray ionization may brake acceleration of the wind. This causes a decrease in the wind terminal velocity and mass flux in the direction toward the X-ray source. We study the effect of X-ray ionization on the stellar wind of B supergiants. We determine the binary parameters for which the X-ray irradiation significantly influences the stellar wind. This can be studied in diagrams that plot the optical depth parameter versus the X-ray luminosity. For low optical depths or for high X-ray luminosities, X-ray ionization leads to a disruption in the wind aimed toward the X-ray source. Observational parameters of high-mass X-ray binaries with B-supergiant components appear outside the wind disruption zone. The X-ray feedback determines the resulting X-ray luminosity. For low X-ray luminosities, ionization is weak, and the wind is not disrupted by X-rays and flows at large velocities, consequently the accretion rate is relatively low. On the other hand, for high X-ray luminosities, the X-ray ionization disrupts the flow braking the acceleration, the wind velocity is low, and the accretion rate becomes high. These effects determine the X-ray luminosity of individual binaries. Accounting for the X-ray feedback, estimated X-ray luminosities reasonably agree with observational values. We study the effect of small-scale wind inhomogeneities, showing that they weaken the effect of X-ray ionization by increasing recombination and the mass-loss. This effect is particularly important in the region of the bistability jump. We show that ultraluminous X-ray binaries with $L_x<10^{40}$ erg/s may be powered by accretion of a B-supergiant wind on a massive black hole.
