Publication date: Mar 2014
Abstract:
The kinetic description of relativistic plasmas in the presence of
time-varying and spatially non-uniform electromagnetic (EM) fields is a
fundamental theoretical issue both in astrophysics and plasma physics.
This refers, in particular, to the treatment of collisionless and
strongly-magnetized plasmas in the presence of intense radiation
sources. In this paper, the problem is investigated in the framework of
a covariant gyrokinetic treatment for Vlasov-Maxwell equilibria. The
existence of a new class of kinetic equilibria is pointed out, which
occur for spatially-symmetric systems. These equilibria are shown to
exist in the presence of non-uniform background EM fields and curved
space-time. In the non-relativistic limit, this feature permits the
determination of kinetic equilibria even for plasmas in which particle
energy is not conserved due to the occurrence of explicitly
time-dependent EM fields. Finally, absolute stability criteria are
established which apply in the case of infinitesimal symmetric
perturbations that can be either externally or internally produced.
Authors:
Cremaschini, Claudio; Tessarotto, Massimo; Stuchlík, Zdeněk;