Nonlinear ion acoustic solitary waves in nonplanar geometry with nonthermal electrons and nonextensive positrons

The nonlinear dynamics of ion acoustic solitary waves (IASWs) in nonplanar geometry are examined in a plasma comprising of adiabatic ions, nonthermal electrons (Cairns distribution), and nonextensive positrons (Tsallis statistics). To examine the deviations from planar wave characteristics. Both cylindrical and spherical geometries are studied. Using the reductive perturbation technique, a modified nonplanar Korteweg–de Vries–Bergers (KdVB) equation is obtained. The effects of positron nonextensivity, electron nonthermality, positron concentration, and temperature ratios on IASW properties are analytically studied. Results demonstrate that nonextensive and nonthermal structures strongly modify wave amplitude, width, and stability, while nonplanar geometry presents additional dispersive effects that can either increase or suppress localization. Both compressive and rarefactive solitons are originate, depending on plasma circumstances. This investigation offers new insights into solitary wave behavior in astrophysical and laboratory plasmas considered by nonthermal and nonextensive particle distributions.