Generalized Langmuir waves in a magnetized plasma with a Maxwellian–Lorentzian distribution

The generalized Langmuir modes in a magnetized plasma whose electrons have a hybrid kappa-Maxwellian velocity distribution are investigated in both the strongly and weakly magnetized regimes. It is found that the kappa distribution significantly alters both the dispersion relation and the Landau damping of the waves from what is ordinarily accepted based on the Maxwellian distribution. In general, the kappa distribution decreases the damping rate of the generalized Langmuir modes in the short wavelength region, but enhances it at the longest wavelengths. The spectral index of the distribution affects the real part of the dispersion relation also, but usually to a somewhat lesser extent. The modifications to both the real and imaginary parts of the dispersion relation are discussed in detail and the implications for plasma waves in space plasmas are briefly noted.