Spherical nonthermal pulsational mode stability thermo-statistically moderated with extra-negative ions

Abstract

The presence of diverse negative ions is well-known to modify different collective waves and instabilities in diverse space and astrophysical environments. We herein investigate the stability dynamics of the spherical nonthermal (kappa-modified) pulsational mode of gravitational collapse (PMGC) excitable in astrophysical dust molecular clouds (DMCs). It primarily explores the impact of the realistic nonthermal negative ionic effects on the PMGC stability features. The high-energetic lighter constituents, such as the electrons, positive ions, and negative ions, are modelled with their respective nonthermal kappa ($\kappa$)-distribution laws. The inertial dust particulates are treated in the viscous fluid fabric. Application of spherical normal mode treatment results in a generalized linear quartic (degree-4) dispersion relation. A computational illustrative platform illuminates the underlying stabilizing and destabilizing factors. It is seen that the cloud size, dust mass, dust charge, nonthermality parameters, equilibrium charged dust number density, and neutral dust viscosity play stabilizing roles. It counters the destabilizing scenarios caused by the equilibrium electron number density, positive ion number density, negative ion number density, neutral dust density, and charged dust viscosity. The fundamental physical mechanisms responsible herein are substantiated and compared in light of the previous predictions. The nontrivial avenues of our study in realizing the Jeans-driven galactic structural unit formation processes, moderated actively with the presence of negative ions in diverse real astronomical circumstances are summarily indicated.