Dusty photoresonant plasma with Coulomb collisions

We have studied the charging of dust particles in a dense photoresonant sodium plasma with electron and ion densities as high as 10(16) cm(-3) produced by laser pumping of the resonance level of Na, which was a small admixture (up to 1%) in an argon buffer gas. We show that the charge of dust particles with a radius of 10 mum at maximum reaches 3 x 10(5) electron charges and that the potential of the dust particles at a low electron bulk loss rate agrees well with the orbital motion limited (OML) model data. The behavior of the electric field near a dust particle was found to be nonmonotonic. We established that the distribution of the potential near a solitary charged dust particle agrees well with the Debye one, but the screening length proves to be much larger than even the electron Debye length; the discrepancies are largest at the afterglow stage of the photoresonant plasma, when the sodium ion with a low recombination coefficient is the main plasma ion. We determined the domain of parameters for a dense plasma where an ensemble of dust particles can crystallize. (C) 2004 MAIK "Nauka / Interperiodica".