Interaction of two solitary waves in quantum electron-positron-ion plasma

The collision between two ion-acoustic solitary waves with arbitrary colliding angle theta in an unmagnetized, ultracold quantum three-component e-p-i plasma has been investigated. By using the extended Poincare-Lighthill-Kuo (PLK) perturbation method, we obtain the KdV equations and the analytical phase shifts after the collision of two solitary waves in this three-component plasma. The effects of the quantum parameter H, the ratio of Fermi positron temperature to Fermi electron temperature sigma, the ratio of Fermi positron number density to Fermi electron number density mu, and the ratio of Fermi ion temperature to Fermi electron temperature rho on the phase shifts are studied. It is found that these parameters can significantly influence the phase shifts of the solitons. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3582089]