Effect of Trapped Superthermal Electrons on Dust Acoustic Kinetic Alfven Waves

Abstract

Kinetic Alfven waves arise when the perpendicular wavelength of ordinary Alfven wave is comparable to the ion Larmor radius. Kinetic Alfven waves play an important role in transporting energy in various space and astrophysical plasma environments, coronal plasma heating, plasma transport in magnetopause as well as in heating Tokamak plasmas, thus heating the plasma to fusion temperatures. Thus, it is very important to study the dynamics of kinetic Alfven waves in order to understand various energy transport mechanisms in plasmas. The trapping of the particles was shown to be important while investigating the nonlinear characteristics of waves. In the present work, we have discussed the effects of vortex-like distribution of electrons on obliquely propagating dust acoustic kinetic Alfven waves in a low β plasma. Using the two potential theory and employing the Sagdeev potential approach, we have investigated the existence of arbitrary amplitude coupled dust acoustic kinetic Alfvenic solitary waves in the frame work of trapped electrons distribution. The present investigation may be beneficial in understanding the propagation of solitary structures in different space environments where trapped populations of electrons have been observed. This study may also be helpful in understanding various non-linear coherent structures in space and astrophysical plasma environments.