High Energy Physical Processes in Active Galactic Nuclei

1.对于具有正负电子对的双温吸积盘，我们发现存在一个临界吸积率，超过这个临界吸积率就不存在稳态解。这一结论被证明是成立的，无论软光子是由回旋加速器提供的高次谐波还是外部热光子。动力学行为对于更高的吸积率变得很重要，这是一个未来的问题。我们研究了吸积盘的质量损失。假设流线的形状是先验的，则基本方程的奇点与音速点重合，临界解给出了风的适当解。如果在自相似假设下同时求解流线的形状，则奇点与声速点不重合。如果圆盘中的密度分布相对平坦，则到达无穷远的解在不通过临界点的情况下变为超音速。我们开始对圆盘风和包括电子-正电子对在内的风进行数值研究。我们研究了活动星系核叠加的X射线背景模型。为了解决光谱差异的问题，我们必须将光谱指数的宇宙学演化或个别来源的光谱平坦化与能量结合起来。如果假设适度的光度演化，任何一个模型都被证明是成功的。我们认为，射电星系热点中的冲击波可以通过费米机制将质子加速到10^&lt；20&gt；eV。我们还发现，对于斜激波，粒子加速的效率比平行激波高达100倍。电子加速及其对活动星系核观测性质的影响是值得研究的问题。

1. We found that for two-temperature accretion disks with electron-positron pairs, there exists a critical accretion rate above which no steady state solutions exist. This conclusion proved to hold irrespective of whether soft photons are supplied by the cyclotron higher harmonics or external thermal photons. Dynamical behavior becomes important for higher accretion rates, which is left as a future problem.2. We investigated mass loss from accretion disks. If we give the shape of streamlines a priori, a singular point of the basic equation is shown to coincide with sonic point and the critical solution gives an appropriate solution of the wind. If we solve the shape of streamlines simultaneously under the assumption of self-similarity, singular point does not coincide with sonic point. Solutions which reach the infinity become supersonic without passing through the critical point if the density distribution in the disk is relatively flat. We started numerical study of disk winds and winds including electron-positron pairs.3. We examined models of the X-ray background in terms of a superposition of active galactic nuclei. To resolve the problem of spectral discrepancy we must incorporate either cosmological evolution of the spectral index or spectral flattening with energy for individual sources. Either model is shown to be successful if moderate luminosity evolution is assumed.4. We argued that shock waves in hot spots of radio galaxies can accelerate protons up to 10^<20>eV through the Fermi mechanism. We also found that for oblique shocks the efficiency of particle acceleration is enhanced up to 100 times compared with parallel shocks. Electron acceleration and its consequence on the observed properties of active galactic nuclei are interesting problems to be studied.