Journal of Plasma Physics

Research Article

Cut-off conditions and existence domains for large-amplitude ion-acoustic solitons and double layers in fluid plasmas

S. Baboolala1 p1, R. Bharuthrama2 p1 and M. A. Hellberga3

a1 Department of Applied Mathematics, University of Durban-Westville, Private Bag X54001, Durban 4000, South Africa

a2 Department of Physics, University of Durban-Westville, Private Bag X54001, Durban 4000, South Africa

a3 Plasma Physics Research Institute, Department of Physics, University of Natal, King George V Avenue, Durban 4001, South Africa

Abstract

It is shown how existence domains for arbitrary-amplitude ion-acoustic solitons and double layers are determined numerically by cut-off conditions on the corresponding Sagdeev potential. A two-electron-temperature model is considered, and in positive-ion plasmas the cut-off conditions are given in terms of the electron parameters, while for negative-ion plasmas such conditions are described in terms of parameters characterizing the role of the negative ion species.

(Received December 06 1989)

Correspondence:

p1 Also at Plasma Physics Research Institute, Department of Physics, University of Natal, King George V Avenue, Durban 4001, South Africa.