Beam-plasma instability of a finite temperature electromagnetoplasma

Abstract

The beam-plasma instability of the collisional magnetoplasma in the presence of a weak longitudinal electric field has been studied. The dispersion relation and the growth rate for the whistler mode instability have been derived and computed. The earlier known results are recovered when the parallel electric field (E0) is reduced to zero. The effect of a parallel electric field is to increase the growth rate. However, the effective electron collision frequency quenches the instability caused by the electrostatic field and the beam. The reversal in the direction of electric field decreases the growth rate. Further, it has been shown that the whistler mode instability can also be excited when the beam particles have no transverse velocity spread. This study may be useful to explain the observations of v.l.f. triggered emissions in the magnetospheric and ionospheric plasma.