A possible mechanism for producing cosmic gamma ray bursts

Abstract

In this paper, we propose a model to explain the energy supply of cosmic γ-ray bursts by means of magnetic energy annihilation in neutral sheets formed in local active regions on magnetic white dwarfs. According to this model the instability process in the plasma consists of two phases, a thermal explosive phase and a steady annihilation phase. The magnetic energy stored in the local source is efficiently converted into kinetic energy and the energy dissipation is at a rate consistent with the observations. With the rapid increase of anomalous resistivity a plasma turbulence field is set up which can immediately be coupled with fast electrons in the Maxwellian high energy tail. The relativistic electrons are then produced within a time as short as 10⁻⁸ sec., which is not in conflict with the fast ascent of brief “spikes” of gamma rays. The calculated results indicate that the γ-rays can also be emitted through synchrotron radiation by the accelerated electrons moving around the magnetic field.

While many details of this theoretical model remain to be cleared up, the present point of view may be taken as a promising basis for future work.