Jeans Instability in Nonideal MHD Plasma Clouds With Geometric Curvature Effects

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.

Automated summary

A generalized nonideal magnetohydrodynamic (MHD) model is used to explore the dynamics of the gravitational instability in a spherical complex molecular cloud, considering various realistic effects. The study reveals that equilibrium temperature and cloud size act as stabilizing factors, while density and magnetic field act as destabilizing factors against cloud collapse. The results suggest that magnetic fields play a role in destabilizing clouds and initiating astrostructure formation dynamics.