030999504:
GRBs from alternating-current jets
由于MRI（磁旋转不稳定性）导致环向磁场极性随机反转，典型的反转时标由磁场放大到动力学重要性的水平的时标决定。具有反转磁场特征的Poyting流主导的喷流提供了一个通过重新连接的自然而有效的途径来驱散能量。GRBs发生在空间分离重联端。在该模型中，伴生的同步辐射能被高度极化并且能够产生平滑和尖锐的光变曲线。我们注意到，作为热力学不稳定性的结果，可能在重联区产生一个冷而致密的纤维。由于对同步辐射的无束缚吸收，可能被用来解释非常硬的X射线谱的产生。
Paczynski（1993）提出GRBs可能产生于高速旋转的大质量的极端相对论喷流。The jets are powered by energy extracted electromagnetically from a rotating accretion disc and/or black hole. A bulk of the jet energy is dissipated and re-radiated in the form of GRBs, at distances 10^13~10^14cm from the core.
The dissipated energy is assumed to be converted efficiently to relativistic electrons, which in turn produce Gamma rays by the synchrotron mechanism.
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