[en] Waves in pair plasmas have a fundamentally different dispersion due to the equal charge-to-mass ratios between negative and positive charges, which mix different time scales. In view of possible applications, e. g., to electron-positron and fullerene pair plasmas, stationary nonlinear structures are investigated for oblique or perpendicular propagation with respect to the static magnetic field. A generalized large amplitude extraordinary mode is found, having a linearly polarized electric field that is orthogonal to both the directions of wave propagation and of the static magnetic field. When the Alfvenic Mach number is in a suitably defined range, the pseudoenergy integral admits solutions with a negative wave electric field, in a cone around parallel propagation, and solutions with a positive wave electric field, at all angles of propagation. The exact analytical solution describing these solitary waves has also been obtained. At weakly nonlinear amplitudes, the solutions reduce to familiar solutions of the Korteweg-de Vries or modified Korteweg- de Vries equations. (C) 2005 American Institute of Physics.
