Effect of ion drag on a pulsational mode of gravitational collapse

The effect of ion drag on the pulsational mode of gravitational collapse (PMGC) is investigated within the partially charged dusty plasma model by fluid dynamics. It is found that the ion drag force significantly enhances the instability of the PMGC. In addition, it is shown that the instability of the PMGC is influenced by the ratio of the abundances of charged to neutral grains. These results can be relevant for the planetesimal formation in dark interstellar clouds. (paper)