Nonthermal effects on the ion-acoustic solitons in Lorentzian electron-ion plasmas

The nonthermal effects on the propagation of the ion-acoustic soliton are investigated in generalized Lorentzian electron-ion plasmas. The soliton solution of the Korteweg-de Vries equation is obtained as a function of the spectral index and modified stretched coordinate in the generalized Lorentzian plasma. It is found that the nonthermal effect on the dispersive term is found to be stronger than that on the nonlinear term. It is shown that the nonthermal effect of the Lorentzian plasma strongly suppresses the stretched coordinate of the ion-acoustic soliton. It is also shown that the nonthermal effect increases the position of the ion-acoustic soliton. In addition, the nonthermal effects on the position of the ion-acoustic soliton are found to be more important in the forward direction. It is found that the nonthermal effect strongly suppresses the amplitude of the ion-acoustic soliton in Lorentzian electron-ion plasmas. It is also found that the nonthermal effect on the amplitude of the ion-acoustic soliton is more significant in the backward direction. (C) 2011 American Institute of Physics. [doi:10.1063/1.3559450]