When Do Ultra-relativistic Shocks Make Energetic Particle Populations?
نویسنده
چکیده
It is claimed that ultra-relativistic, magnetized, electron-ion shocks are, for most magnetic geometries, poor accelerators of non-thermal particles. The phenomenon of “missing” early X-ray afterglow observed in many of the Swift gamma-ray burst (GRB) afterglow data may simply be due to this fact. Rapid time variability of the X-ray emission could be produced by fluctuations in the orientation of the ambient magnetic field. Subject headings: shocks, magnetic fields, cosmic rays
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