Jeans Instability in Nonideal MHD Plasma Clouds With Geometric Curvature Effects

Abstract

A generalized nonideal magnetohydrodynamic (MHD) model to explore the excitation dynamics of the gravitational (Jeans) instability in a spherical complex molecular cloud is reported. It includes the realistic effects of viscoelasticity, buoyancy, polytropicity, volumetric expansion, and so forth. A standard technique of spherical normal mode analysis, without invoking any quasi-classic approximation over the non-Newtonian astrocloud, yields a unique type of generalized linear cubic dispersion relation. We see numerically that the equilibrium temperature and radial cloud size act as stabilizing (decelerating) agencies against the self-gravity. Contrariwise, the mean density and magnetic field act as destabilizing (accelerating) factors against the nonlocal cloud collapse. The various propagatory and phase-space features are illustrated. The magnetic field as a cloud destabilizer in spherical geometry to initialized astrostructure formation dynamics is a new result. Its source is in the concurrent action of the diversified meanfluidic non-ideality factors against the formal planar picture. It has interestingly a good agreement with the various earlier astronomic observations based on the experiments widely founded on the magneto-optic Zeeman effects.