Ion acoustic solitary wave in homogeneous magnetized electron-positron-ion plasmas

The nonlinear ion acoustic wave propagating obliquely with respect to an external magnetic field is studied in a homogeneous magnetized electron-positron-ion plasma. It is found that the amplitude of the solitary structure increases with the percentage presence of positrons, which is opposite behaviour to the previous study of these waves in an unmagnetized plasma. The speed of the obliquely propagating soliton in a magnetized plasma turns out to be subsonic, while it is supersonic in the unmagnetized case already studied