Nonlinear waves and shocks in relativistic two-fluid hydrodynamics

Relativistic shocks are present in a number of objects where violent processes are accompanied by relativistic outflows of plasma. The magnetization parameter σ = B ²/4πnmc ² of the ambient medium varies in wide range. Shocks with low σ 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 σ≪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 ∼ 4πnm _ic ²γ. A large cross-shock potential eφ/mic ²γ0 ∼ B ²/B _eq ² develops across the electron-ion shock front. This potential is responsible for electron energization.