Coronal mass ejection(CME) is a phenomenon of solar eruption, it causes the flux rope and magnetized plasma to be thrusted outward. In this process, huge magnetic energy is rapidly released and converted to other forms of energy. It is believed that catastrophe and magnetic reconnection trigger the CME. Because the sun is closest to the earth and play an important role in human life, the solar physics has further development. In the field of high energy astrophysics, there are some physical phenomena have the operation of a common physical mechanism with solar CME (e.g. magnetar giant flares and episodic jets from black hole and accretion disk systems). Huge magnetic energy is released and plasmoid is ejected from the system in this process, and the details are still unknown. Therefore, applications of the solar cme model to the phenomena in the high-energy astrophysics are very meaningful. Giant flares on soft gamma-ray repeaters that are thought to take place on magnetars release enormous energy in a short time interval. Their power can be explained by catastrophic instabilities occurring in the magnetic field configuration and the subsequent magnetic reconnection. By analogy with the coronal mass ejection (CME) events on the Sun, we develop a theoretical model via an analytic approach for magnetar giant flares. In this model, the rotation and/or displacement of the crust causes the field to twist and deform, leading to flux rope formation in the magnetosphere and energy accumulation in the related configuration. When the energy and helicity stored in the configuration reach a threshold, the system loses its equilibrium, the flux rope is ejected outward in a catastrophic way, and magnetic reconnection helps the catastrophe develop to a plausible eruption. By taking SGR 1806 - 20 as an example, we calculate the free magnetic energy released in such an eruptive process and find that it is more than 10^47 ergs, which is enough to power a giant flare. The released free magnetic energy is converted into radiative energy, kinetic energy and gravitational energy of the flux rope. We calculated the light curves of the eruptive processes for the giant flares of SGR 1806 - 20, SGR 0526-66 and SGR 1900+14, and compared them with the observational data. The calculated light curves are in good agreement with the observed light curves of giant flares. In many astrophysical black hole systems, episodic jets of plasma blobs have been observed, although the origin of the episodic ejection of blobs is unclear. Base on the model proposed by Yuan et al., we develop an magnetohydrodynamical model for episodic ejections of the plasma blob from black hole and accretion disk systems, considering the relativistic effect. By taking Sgr A* and the stellar size black hole for examples, we study the dynamics of the plasma blob. Our model results show that the blobs can attain large Lorentz factor quickly and undergo expansion after thrusting outward. And we further study the collision between two consecutive ejections in our model, and find the consecutive plasma blobs from the stellar size black hole can collide with each other and each of them has magnetic energy of more than 10^50 ergs in our calculation. In the this collision, about half the magnetic energy is released by magnetic reconnection, so multiple collisions among several such blobs can power a Gamma-ray burst.
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