Characterization of Dusty Plasmas in the Earth’s Mesosphere Using Radiowave Heating

Abstract

Recently it has become evident that significant diagnostic information may be available to characterize charged sub‐visible mesospheric dust layers from the temporal behavior of the associated electron irregularities during radiowave heating which ultimately modifies the mesospheric electron temperature. Particularly important time periods of the irregularity temporal behavior are during the turn‐on and turn‐off of the radio wave heating. The objective of this work is to first consider the physical processes that control the evolution of electron irregularities associated with mesospheric dust layers during radio wave heating. It is shown that two dominant processes are dust charging and ambipolar diffusion. In particular, it will be shown that a fundamental parameter that controls the temporal behavior is the ratio of the dust charging to ambipolar diffusion time during the turn‐on and turn‐off period. Both computational and analytical models are described that may be used to directly investigate the electron irregularity temporal evolution with particular emphasis placed on modeling the electron irregularity temporal evolution during the time periods when the radio wave heating is turned on and off. The models results may then be used to obtain diagnostic information on the characteristics of the charged dust layer, such as dust density and radius. Predictions of the models are used to describe possibilities for new experiments that may provide further diagnostic information on charged mesospheric dust layers.