Collisional charging of interstellar grains
B. T. Draine, B. Sutin;
ApJ, 1987, 320, 803
ABSTRACT:Collisional charging of small interstellar particles is reexamined, including effects due to electrostatic polarization of grains by the electric
fields of approaching charged particles.
The interaction potentials and
resulting energy-dependent collisional cross sections are discussed and used
to obtain the collisional charging rate for grains of specified charges
in a thermal plasma.
The probability distribution of the grain charges
is obtained, and the application of the results to the interstellar
medium is illustrated by considering the power-law grain size distribution
of Mathis, Rumpl, and Nordsieck (1977).
It is found that dust grains with
such a size distribution can contribute appreciably to the recombination
of metal ions in dark clouds.
KEYWORDS: charged particles, interstellar matter, particle collisions, charging, cooling, electron-ion recombination, grain size
PERSOKEY:dust, polarisation, ,
CODE: draine87