Pulsational mode behaviour in complex non-extensive non-thermal viscous astrophysical fluids

Department of Physics, Tezpur University - Napaam-784028, Tezpur, Assam, India

^(a) pkk.766@live.com (corresponding author)

Received: 16 June 2017
Accepted: 12 September 2017

Abstract

A semi-analytic evolutionary model is classically constructed to see the pulsational mode dynamics of gravitational collapse in a hydrostatically bounded complex non-thermal astrocloud on the Jeans scales of space and time. The multi-fluidic model consists of non-extensive electrons and ions, and massive dust grains along with partial ionization in flat space-time. A linear Fourier-based normal mode analysis around the defined static (homogeneous) equilibrium reduces the basic cloud equations into a quartic (biquadratic) dispersion relation with a unique set of multi-parametric coefficients. It is interestingly found that non-thermal associations in the cloud pave the way for faster normal mode propagation. The neutral dust viscosity plays a decisive role towards a transition of the pulsational mode from a non-dispersive to a dispersive form. It is also observed that the viscosity has a stabilizing influence on the cloud. The dust-charge variation is noted to play an insignificant role on the stability. The results may be significant in understanding the dynamic non-homological cloud collapse leading to a hierarchical initiation of a bounded structure formation in diverse astro-cosmic anti-equilibrium environs.