135-139Wave-particle interaction in the magnetosphere has been studied for wave frequencies at the cyclotron harmonics of electrons and ions. A generalized dispersion relation for electrostatic wave, propagating nearly perpendicular to the magnetic field in non-Maxwellian plasma has been considered. Expressions of damping and growth rate for electrostatic electron and ion cyclotron harmonic (ICH) waves have been derived and computed results have been demonstrated for the magnetospheric plasma parameters. The growth of electron cyclotron harmonic waves may be interpreted in terms of the observed electron cyclotron harmonic emissions due to energetic electrons and ICH waves by energetic ions in the magnetospheric plasma. The damping of the waves may explain the heating of the magnetospheric plasma
