Nucleus-acoustic waves: Excitation, propagation, and stability

Abstract

The propagatory excitation dynamics of the collective nucleus-acoustic waves supported in a strongly coupled self-gravitating degenerate quantum dusty plasma (QDP) system, widely realizable as the constitutive matter for white dwarfs and other compact astro-objects, is semi-analytically studied. The spherically symmetric QDP is composed of strongly coupled non-degenerate heavy nuclei, weakly coupled degenerate light nuclei, and non-relativistically and ultra-relativistically degenerate lighter electrons. A standard normal spherical mode analysis is applied to derive a complex generalized dispersion relation. A numerical illustrative calculation is executed in the ultra-low frequency approximation to see the dependency of various sensible parameters on the instability evolution. It is seen that the relative nuclear charge-mass coupling parameter (β) acts as a destabilizing and stabilizing agents in the non-relativistic (NR) and ultra-relativistic (UR) limits, respectively. The ratio of the charge density of heavy-to-light nuclear species (μ) acts as a destabilizer (stabilizer) in the NR (UR) limits, to the instability. The quantum parameter (H′) interestingly acts as a stabilizing agency in both the NR-UR limits.