Nonlinear generation of the second harmonic in Alfven resonance oscillations of the magnetosphere

Nonlinear generation of the second harmonic in the resonance small-scale disturbance of an Alfven type has been studied. It has been indicated that the substantial feature of the second nonlinear harmonic is the fact that not only toroidal oscillations but also plasma oscillations along the magnetic field, plasma density fluctuations, and oscillations of the magnetic field longitudinal component are present in a resonance layer; in this case, the longitudinal field disturbance of the second harmonic can be even higher than that of the first harmonic. The spatial distribution of the amplitudes of different components of the second harmonic in a resonance layer is described.