Developments of Numerical Magnetohydrodynamic Simulators of Accretion Disks with Application to Time Variabilities and Jet Formation

适用于吸积盘全局模拟的三维磁流体动力学程序已在大规模并行计算机上实现。通过应用该程序，我们发现在喷流和星际物质之间的界面处形成了分子鞘。我们还实现了光子传输代码，从模拟结果中计算辐射光谱。基于超临界黑洞吸积流的辐射流体动力学模拟结果，再现了在超铝X射线源（ULXs）中观测到的X射线谱。通过三维磁流体动力学模拟，我们还发现吸积盘中的平均磁场方向在发电机作用下准周期性地反转。

Three-dimensional magnetohydrodynamic codes applicable to global simulations of accretion disks have been implemented to massive parallel computers. By applying this code, we showed that molecular sheath is formed at the interface between the jet and the interstellar matter. We also implemented photon transfer codes to compute the radiation spectrum from the simulation results. Based on the results of radiation hydrodynamic simulations of supercritical black hole accretion flows, we reproduced the X-ray spectra observed in ultraluminous X-ray sources (ULXs). We also showed by three-dimensional magnetohydrocynamic simulations that the direction of mean magnetic fields in accretion disks reverses quasi-periodically by dynamo action.