Solitary kinetic Alfvén waves in the inertial limit region

Abstract

Considering the effects of hot ions and Lorentz force, a numerical study on the properties of solitary kinetic Alfvén waves (SKAWs) in the inertial limit region in the magnetosphere is presented. In contrast to the results obtained by Hasegawa and Mima [Phys. Rev. Lett. 37, 690 (1976)], Shukla et al. [J. Plasma Phys. 28, 125 (1982)], and Wu et al. [Phys. Plasmas 3, 2879 (1996)], both hump and dip density Alfvénic solitons can exist in the inertial limit region (β≪2me/mi, where β (= 2μ0nTe/B20) is the ratio of thermal pressure to magnetic pressure). These results provide a more realistic interpretation for the SKAWs phenomena observed by the Freja satellite, in which not only SKAWs accompanied by dip density solitons, but also SKAWs accompanied by hump density solitons were found at the Earth's ionospheric altitude. © 2000 American Institute of Physics.