Spherical nonlinear ion-acoustic solitary waves in Titan’s atmosphere

Propagation of spherical nonlinear ion-acoustic
solitary waves in positive and negative ion plasmas with
superthermal electrons is investigated. The effects of perturbations
of the azimuthal and zenith-angle as well as the
radial coordinate on the solitary wave profile are reported.
The existence domains and the characteristics of the spherical
solitary pulses are examined. The solitary excitations
are found to be strongly dependent on the plasma parameters;
the mass ratio of the positive-to-negative ions, electrons
superthermality, and the spherical geometry. The role of superthermal
electrons in formation of the spherical nonlinear
ion-acoustic solitary excitations for two ion mass groups in
Titan’s upper atmosphere is investigated.