Stability Analysis of Ion-Acoustic Solitary Waves in Negative Ion Plasmas

Magnetized negative ion plasma system that contains both inertial positive and negative ion species with non-inertial q -distributed electrons is considered. The basic properties of obliquely propagating ion-acoustic solitary waves in such negative ion plasma medium are investigated by using the reductive perturbation approach. The latter remains valid when the amplitude is small but not negligible. The impact of external magnetic fields, oblique angle, and non-extensive parameter on the fundamental characteristics (including speed, amplitude, width, and polarity) of ion-acoustic solitary waves are examined. The stability and instability of obliquely propagating ion-acoustic solitary waves are also discussed in their dependence of plasma parameters. Based on the charge state ratio of positive and negative ions and the non-extensive parameter, the opposite polarity of ion-acoustic solitary waves is observed. The implications of our results in magnetized negative ion plasma environments related to both space and laboratory plasmas are discussed briefly.