Head-on collision of ion-acoustic solitary and shock waves in a two-electron-temperature plasma

A plasma composed of ions and two species of electrons at different temperatures (hot and cold) is considered. A modified Korteweg-de Vries equation is derived which describes the evolution of rarefactive and compressive ion-acoustic solitons or steady electrostatic shocks, according to whether the relative concentrations and the relative temperatures assume critical values. By using the extended Poncare-Lighthill-Kuo perturbation method the head-on collision between two countertravelling ion-acoustic pulses are studied. It is shown that the interaction between solitons produces a shift in the trajectories of motion, such an effect also exists for interacting steady shocks but with different characteristics.