Nonlinear waves and shocks in relativistic two-fluid hydrodynamics

Abstract : Relativistic shocks are present in a number of objects where violent processes are accompanied by relativistic outflows of plasma. The magnetization parameter sigma = B-2/4 pi nmc(2) of the ambient medium varies in wide range. Shocks with low sigma are expected to substantially enhance the magnetic fields in the shock front. In non-relativistic shocks the magnetic compression is limited by nonlinear effects related to the deceleration of flow. Two-fluid analysis of perpendicular relativistic shocks shows that the nonlinearities are suppressed for sigma << 1 and the magnetic field reaches nearly equipartition values when the magnetic energy density is of the order of the ion energy density, B-eq(2) similar to 4 pi nm(i)c(2)gamma. A large cross-shock potential e phi/m(i)c(2)gamma(0) similar to B-2/B-eq(2) develops across the electron-ion shock front. This potential is responsible for electron energization.