Kinetic and hydrodynamic instabilities of straight beams under an anomalous Doppler effect

With а special reference to electrons captured bу а longitudinal wave and а straight electron bearn in а constant rnagnetic field it is dernonstrated that in conditions of anornalous Doppler effect incrernents of vibration can develop which are proportional to the resonance value of the electron distribution function rather than to the derivative of this function with respect to velocities sirnilar to direct and inverse darnping of Landau waves.