Kinetic study of electrostatic modes in a Lorentzian Electron-Positron-Ion (EPI) plasma

Abstract The propagation and Landau damping of Langmuir Waves (LWs) and Ion-Acoustic Waves (IAWs) in Electron-Positron-Ion (EPI) plasma are investigated using Kinetic theory approach, with all the species to be Kappa or Lorentzian distributed. We observed that the Landau damping rates γ ( κ ) of Langmuir waves and IAWs in Lorentzian EPI plasma strongly depend upon the spectral index κ i.e., non-thermality parameter, wave number k , the positron temperature T p and the positron concentration or number density n p . The Landau damping γ ( κ ) of Langmuir waves was found to be increased with higher positron temperatures T p , whereas, that of IAWs was found to increase with lower positron temperatures T p . Moreover, it was observed γ ( κ ) of LWs shows a decrease with increase in positron concentration while γ ( κ ) of IAWs tends to increase.