Head-on collision of ion-acoustic solitary waves in multicomponent plasmas with positrons

The head-on collision between two ion-acoustic solitary waves in an unmagnetized multicomponent plasma consisting of hot ions, hot positrons, and two-electron temperature distributions is investigated using the extended Poincare-Lighthill-Kuo method. The Kortwege-de Vries equations and the analytical phase shifts after the head-on collision of two solitary waves in this multicomponent plasma are obtained. The effects of two different types of isothermal electrons, the ratio of the hot ion temperature to the effective temperature, the ratio of the effective temperature to the positron temperature, the ratio of the number density of positrons to that of electrons species, and the physical processes (either isothermal or adiabatic) on the phase shifts are studied. It is found that these parameters can significantly influence the phase shifts of the solitons. The relevance of this investigation to space and laboratory plasmas is pointed out. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3480096]