Electron Injection in a Young Supernova Evolution Towards a Supernova Remnant

摘要

The blast wave shock in SN 1993J has high sonic and Alfvenic Mach numbers—ideal for ion plasma instabilities which generate plasma waves that energize electrons upon interaction. Plasma in the shock-circumstellar interface is strongly magnetized, with the field energy density far exceeding that of the relativistic particles. This small “equipartition” for a young type IIb SN contrasts those of older Supernova remnants. Evolution of the radio spectrum of young supernovae can determine the change of the shock compression ratio as the SN ages and through comparison with models of particle acceleration coupled with hydrodynamics, can indicate the injection factor: the fraction of the total electrons that end up in the superthermal tail.