Dust grains in plasma with coulomb collisions

Dust-grain charging in a dense plasma with electron and ion concentration up to 1016cm−3, where the electron transport cross section is dominated by Coulomb collisions, was investigated. It was established that the charge of an isolated dust grain increases with electron concentration, whereas its potential is almost constant in the range 1014–1016cm−3 of electron concentrations studied. It is shown that the self-consistent electric-field potential at moderate and large distances from the dust grain is well approximated by the Debye expression, but the screening radius is appreciably larger than even the electron Debye radius. The region of parameters of a dense photoresonance sodium plasma, where the dust-grain ensemble may crystallize, was established.