Dynamic spectral density function of a dusty plasma.

Abstract

Dust particles in a plasma can be highly charged. The Debye screening of the dust particles can seriously affect the Coulomb collective interaction. The dynamic spectral density function of a dusty plasma in a weak turbulence and weakly coupled state has been derived by kinetic theory. A detailed analysis of the electron dynamic spectral density function in the dusty plasma shows that the Debye screening of the dust particles increases the electron density correlation of the plasma considerably. This increase is proportional to the ratio of densities ${\mathit{n}}_{\mathit{d}}$/${\mathit{n}}_{\mathit{e}}$ and the square of the dust charge number ${\mathit{Z}}_{\mathit{d}}^{2}$=(${\mathit{q}}_{0}$/e${)}^{2}$. A correction of electron density correlation of an order P${\mathrm{\ensuremath{\Omega}}}_{\mathit{c}}^{2}$/${\mathrm{\ensuremath{\omega}}}^{2}$ results because of the change of the charge on the dust particles. Here P is a parameter describing the importance of the dust charge in the plasma, ${\mathrm{\ensuremath{\Omega}}}_{\mathit{c}}$ is the charging frequency of the dust particle, and \ensuremath{\omega} is the fluctuation frequency of the plasma. \textcopyright{} 1996 The American Physical Society.