STUDY OF WHISTLER MODE WAVE BY INJECTION OF RELATIVISTIC HOT ELECTRONS BEAM IN THE MAGNETOSPHERE OF URANUS

Abstract

In present paper, the efiect of relativistic hot electron beam for fleld aligned Whistler mode waves has been studied theoretically in the presence of AC electric fleld perpendicular to magnetic fleld. Studies have been performed using perturbative approach along with the method of characteristic solutions and are valid for comparatively small ambient magnetic fleld of Uranus, of the order of nano Tesla, as observed by Voyager 2. The detailed derivation and calculations has been done for dispersion relation and growth rate for magnetosphere of Uranus. Analyses are done by changing various plasma parameters which are explained in result and discussions section of this paper. Extensive study of wave- particle interactions and numerical calculations concludes that in case of injection of a distribution of particles having a positive slope in v?, temperature anisotropy remains the main source of free energy. It is seen that other efiective parameters for the growth of whistler mode waves are AC frequency and higher number density of hot electrons. We also learn that even the minimal presence of such energetic particles having a positive slope of distribution function and increasing power of perpendicular thermal velocity can increase the growth rate signiflcantly in the magnetosphere of Uranus. The present work is basically based upon the theoretical investigation and mathematical analysis of the magnetosphere of Uranus, supported by satellite data.