Electromagnetic instabilities in rotating magnetized viscous objects
  We study electromagnetic streaming instabilities in thermal viscous regions
of rotating astrophysical objects, such as, magnetized accretion disks,
molecular clouds, their cores, and elephant trunks. The obtained results can
also be applied to any regions of interstellar medium, where different
equilibrium velocities between charged species can arise. We consider a weakly
ionized multicomponent plasma consisting of neutrals and magnetized electrons,
ions, and dust grains. The effect of perturbation of collisional frequencies
due to density perturbations of species is taken into account. We obtain
general expressions for perturbed velocities of species involving the thermal
pressure and viscosity in the case in which perturbations propagate
perpendicular to the background magnetic field. The dispersion relation is
derived and investigated for axisymmetric perturbations. New compressible
instabilities generated due to different equilibrium velocities of different
charged species are found in the cold and thermal limits when the viscosity of
neutrals can be neglected or is important. The viscosity of magnetized charged
species is negligible for considered perturbations having wavelengths much
larger than the Larmor radius of species. At the same time, the neutrals are
shown to be immobile in electromagnetic perturbations when their viscosity is
sufficiently large.
