On the stability of self-gravitating magnetized dusty plasmas

The effects of a homogeneous magnetic field and the plasma nonuniformity on the dispersion relations of various electrostatic waves in self-gravitatin g magnetized dusty plasmas have been investigated. For this purpose, the ki netic dielectric response functions for the electrons and ions distribution s have been used and the dielectric response function for the magnetized du st grains has been derived from the hydrodynamic equations that include the self-gravitational potential. Thus, extremely massive charged dust grains are subjected to both the electromagnetic and gravitational forces. Analyti cal studies of the dispersion relations in various frequency and wave numbe r regimes reveal that both the magnetic fields and plasma inhomogeneities c ontribute to the stability of a self-gravitating dusty plasma system. The r esults of this investigation should be useful in understanding the stabilit y of dusty proto-stars and dusty dark molecular clouds, which are held in s trong magnetic fields and equilibrium density gradients. (C) 1999 American Institute of Physics. [S1070-664X(99)01903-5].