Nonlinear electron plasma waves in fully relativistic plasmas

Abstract

Propagation of nonlinear electron plasma waves is investigated in a fully relativistic election-ion plasma using two-fluid hydrodynamic model. The relationship between pressure and density is assumed to be of polytropic form for relativistic electrons. The conditions for the validity of adiabatic equation of state for electron fluid is also discussed. The well-known pseudopotential approach is employed for arbitrary amplitude wave analysis and superluminous and subluminous wave phase speed cases are discussed in two special frames of references transformed under Lorentz-transformation. The set of model equations is solved analytically as well as numerically to obtain nonlinear periodic wave structures of electron plasma waves in a fully relativistic plasmas. A special case of solitary wave structure formed in subluminous phase speed case is also discussed in detail, which has not been done in the previous published literature. The effects of electron temperature and phase speed of the plasma wave (i.e., for subluminous and superluminous wave phase speed cases) on the amplitude of nonlinear periodic wave and solitary wave structures are also presented with its possible applications to the astorphysical environment.