EFFECT OF PARALLEL ELECTRIC-FIELD ON THE ELECTROSTATIC ION-CYCLOTRON INSTABILITY

Using the particle aspect theory, the effect of parallel electric field on the electrostatic ion cyclotron instability has been studied with the modification of distribution function in non-drifted, bi-Maxwellian collisionless megnetoplasma. The plasma particles are divided into resonant and non-resonant particles. The resonant particles are considered to participate in the energy exchange with the wave. The energy transferred to the resonant particles along and transverse to the ambient magnetic field has been evaluated. The expression for growth rate has been derived. The reduction of growth rate with the increase of parallel electric field has been predicted. The growth rate and resonant particles energy perpendicular to and along the ambient magnetic field have been evaluated for different parameters. The results show that the effect of parallel electric field has the stabilizing effect and reduces the resonant particles energy. The applicability of the study has been indicated for the auroral acceleration process.