Effect of radiative cooling on molecular cloud collapse

Abstract

The effect of the radiative cooling of electrons on the gravitational collapse of molecular clouds consisting of neutral particles along with electrons, ions, and electrically charged dust grains with fluctuating charge is investigated. We include the effect of radiation on the gravitational collapse of the neutrals only through the ion-neutral and grain-neutral collisions. In the absence of thermal conduction, the radiative condensational instability may couple with the Jeans mode in the long-wavelength regime. However, when the thermal conduction is switched on, gravitational collapse is not altered in any significant way by the radiative mode. The charge fluctuations on the grains may slightly reduce the Jeans growth rate as the collision induced plasma electric field, which is in phase with the gravitational field, is slightly reduced by the charge variation on the grains.