The Theory of Relativistic Jet Formation in Galactic Sources: Towards a Unified MOdel

Abstract

I review recent progress in the theory of relativistic jet production. The presently favored mechanism is an electrodynamic one, in which charged plasma is accelerated by electric fields that are generated by a rotating magnetic field. The most pressing issues of current interest are understanding what factors control the jet power, its speed, and its degree of collimation, and how these properties determine the type of jet observed and its effect on its environment. Recent observations of microquasars, pulsars, gamma-ray bursts (GRBs) and core-collapse supernovae indicate that jets play an important, and in some cases possibly dominant, role in each of these. The presence of a jet in all cases may provide an important clue to how these sources may be related. Based on these observations, and on recent theoretical investigations, I propose an evolutionary scheme that attempts to unify all of these relativistic galactic jet sources. I also discuss several important issues that must be resolved before this (or another scheme) can be adopted.