High-frequency waves in the solar coronal plasma

We derived numerical solutions of a dispersion equation in order to analyze the effect of finite plasma temperature on the high-frequency wave dispersion characteristics in conditions of hot magnetized plasma in the solar corona. Spectra of the high-frequency eigen modes of these plasma were determined in conditions when the electron gyrofrequency is lower than the plasma one and when the eigen modes frequencies are higher than the electron gyrofrequency. The longitudinal wave mode is shown to turn to the Z-mode at refractive index $n < 1$. At refractive index $n \gg 1$, the longitudinal wave frequency increases when n grows, and these waves go to strongly damped ones with an anomalous dispersion. We interpret some spectral features of type II and IV radio bursts in the solar corona.