Alfven Wave Instability with Streaming Electrons in Magnetized Dusty Plasma. (2018) - Prakash, Ved
Abstract: Alfven waves are observed in the solar wind and may be responsible for generation of the parallel electric fields in the aurora. In the present work, we investigate the electromagnetic Alfven waves in three component dusty plasmas. The negative ions streaming through magnetized dusty plasma drive Alfven waves to instability via Cerenkov interaction. The presence of charged dust grains and streaming electrons modify the dispersion relation of low frequency Alfven waves. The charge and number density of dust grains and external magnetic field significantly modify the dispersion properties of these waves. The impact of the electron streaming velocity and the thermal electron speed on the growth of the instability is studied analytically. The Alfven modes with phase velocity comparable to the electron streaming velocity possess a large growth rate. The maximum value of growth rate increases with an increase in thermal electron speed or electron temperature. However, the maximum value of growth rate decreases with an increase in dust grain number density. Numerical calculations are done using the plasma parameters suitable for the earth's magnetosphere. The results of the proposed theory are applied to understand some of the experimental observations.