Fermi Gamma-ray Space Telescope

Some New Approaches to Particle Acceleration and Gamma-Ray Emisssion in Relativistic Plasmas: Magnetoluminescence, Electromagnetic Detonation and Gamma-Ray Scintillation

R. Blandford
Y. Yuan, W. East, K. Nalewajko, J. Zrake

Abstract:

Dramatic bursts of gamma ray emission are observed from PWN, AGN and GRB. In each case, it appears that large volumes of electromagnetic field are rapidly converted into ultrarelativistic electron and positron energy which is then quickly radiated as synchrotron or inverse Compton emission, a general process that we call 'magnetoluminescence'. This may be triggered by instability of force-free magnetic equilibria and evolve via the formation of current sheets and, especially, detonations in which the electric field may exceed the magnetic field and the conversion of the associated electromagnetic energy into particle and photon energy is analogous to the release of chemical energy in a conventional explosion. Recent calculations, involving Force Free, Relativistic MHD and Particle in Cell approaches will be described. The observational consequences of these processes will be outlined, including the possibility that rapid gamma ray variability is due to caustic formation in the beamed emission from relativistically-moving, emitting surfaces.