Abstract
The characteristics of the head-on collision between two-quantum ion-acoustic solitary waves (QIASWs) in a dense electron-positron-ion plasma are investigated. Using the extended Poincare-Lighthill-Kuo (PLK) method, the Korteweg-de Vries (KdV) equations and the analytical phase shifts, after two QIASWs collision occurs, are derived. This study is a first attempt to illustrate the effects of both of the quantum diffraction corrections and the Fermi temperature ratio of positrons to electrons on the phase shifts. It is found that the electron-positron-ion plasma parameters modify significantly the phase shifts of the two colliding solitary waves. (C) 2009 Elsevier B.V. All rights reserved.