Research on Black Hole Magnetosphere

对活动星系核的观测研究表明，在中心区域存在一个巨大的黑洞。本文从黑洞磁层模型出发，利用广义相对论磁流体动力学（MHD）方程，研究了喷流形成和X射线辐射等天体物理活动。该方法是考虑以下三个磁层区域和分析等离子体流和磁场线的配置。黑洞吸积的内卷风区域：对于黑洞附近的磁主导风，磁场与等离子体粒子之间的相互作用可以非常有效地传输能量和角动量。结果表明，MHD波的产生对等离子体的入射运动产生了很大的扰动，而等离子体向旋转轴方向的准直传播则触发了类似喷流的出风.向外延伸的外出风区：研究磁力线的磁自准直作用，估计出风喷流结构的特征尺度，并给出赤道面上的边界条件。结论是任何观测到的喷流都不应该有太高的洛仑兹因子.粒子产生区是进出风之间的边界层：提出了大电流密度薄壳层中的焦耳耗散是等离子体粒子稳定供应到磁层的机制。这个想法得到了验证，通过显示生产的输入和输出的质量通量与热通量转换成X射线辐射。统一处理这三个不同的区域，通过粒子产生机制将磁层内部结构与外部结构联系起来，这仍有待于今后的工作。

Observational studies of active galactic nuclei suggest the existence of a massive black hole in the central region. In this research the astrophysical activities, such as jet formation and X-ray radiation, have been investigated in terms of a model of the black hole magnetosphere, by using the general ralativistic magnetohydrodynamic (MHD) equations. The approach is to consider the following three magnetospheric regions and to analyze plasma flows and magnetic field-line configurations.1. The inner ingoing-wind region with accretion onto black hole : For magnetically dominated winds near the black hole, the interaction between magnetic field and plasma particles transporting energy and angular momentum is found to work very effectively. Then it is shown that the generation of MHD waves highly disturbs the ingoing motion of plasma, and the collimated propagation towards therotation axis occurs as a trigger of jet-like outgoing winds.2. The outer outgoing-wind region extending to large distances : The magnetic self-collimating action of field lines is studied to estimate characteristicscales of the jet structure of relativistic outgoing winds and to give a boundary condition on the equatorial plane. The conclusion is that any observed jets should not have too high Lorentz factors.3. The particle creation region which is a boundary layr between ingoingand outgoing winds : The Joule dissipation in a thin shell with a large current density is proposed as a mechanism of steady supply of plasma particles into the magnetosphere. This idea is verified, by showing the production of ingoing and outgoing mass fluxes with a heat flux which is converted into X-ray radiation. Anunified treatment of the three different regions to relate the inner magnetospheric structure to the outer one through the particle creation mechanism remains in future works.