Kinetic study of twisted electron plasma waves in q-nonextensive plasmas

Relying on the kinetic description, the electron-plasma (EP) waves carrying distinct orbital angular momentum (OAM) states are investigated in q-nonextensive plasma consisting of inertial electrons with static background of positive ions. Deriving an expression for the dielectric response function, the dispersion relation and Landau damping frequencies are analyzed both analytically and numerically. It is found that weakly damped regions of the EP waves strongly depend on the non-extensivity (q) and twist (eta) parameters. The presence of finite OAM results in the longer range of the values in terms of normalized wavenumber for which the EP waves are weakly damped. However, maximum range of weakly damped wavenumbers is obtained when the longitudinal and azimuthal wavenumbers are equal, viz. twist parameter becomes unity. For very large twist parameter, the results of the twisted wave model coincide with the planer wave model. (c) 2018 Author(s).