Dust-charge fluctuations with non-Maxwellian distribution functions

Dust grains immersed in a plasma can exhibit charge fluctuations in response to the oscillatory plasma currents flowing onto them. The fluctuation electrodynamics of dusty plasmas are determined by taking into account the dynamics of charging processes associated with plasma currents. Expressions for the charging currents are derived using kappa and generalized (r, q) distribution functions. The dispersion relation of dust-acoustic waves is modified while taking into account these distribution functions. Further, it is found that in the limit (i) r = 0, q → ∞ and (ii) κ → ∞, the expressions of the current modified with (r, q) and kappa distributions reduce to the Maxwellian current.