Dust Charging in a Plasma Consisting of Regularized Kappa Distributed Electrons and Ions.

The charging of dust grains in a plasma with regularized kappa distributed electrons and ions has been investigated. The effects of the electrons’ and ions’ cutoff parameters and spectral indices on the dust grain surface potential are numerically analyzed. It is shown that the enhancement of energetic electrons increases with the decrease of the electron spectral index and cutoff parameter, leading to an increase in the magnitude of dust grain charge. Conversely, the magnitude of dust grain charge varies inversely with the decrease of ion spectral index and cutoff parameter. In addition, the critical ion spectral index for the charge of dust grain changing from negative to positive increases with the increase of the electron spectral index and cutoff parameter, and the decrease of the ion cutoff parameter. The results obtained can be helpful in understanding the dust charge state in laboratory and space dusty plasmas where the plasma particles deviate from the Maxwellian distribution. [ABSTRACT FROM AUTHOR]