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arXiv · 2207.09939

Fireball sheath instability

Abstract

The evolutionary existence of plasma fireballs is a generic phenomenon realizable in diversified physical plasma-dominated circumstances starting from the laboratory to the astrocosmic scales of space and time. A fair understanding of such fireballs and associated instabilities is indeed needed to enrich astroplasmic communities from various perspectives of applied value. Naturally occurring plasma fireball events include novae, meteors, stellar structures, etc. We propose a theoretical model formalism to analyze the plasma fireball sheath (PFS) instability with the application of a quasi-linear perturbative analysis on the laboratory spatiotemporal scales. This treatment reduces the steady-state system into a unique second-order ordinary differential equation (ODE) on the perturbed electrostatic potential with variable multiparametric coefficients. A numerical illustrative platform to integrate this ODE results in an atypical set of peakon-type potential-field structures. It is noticed that both the potential and field associated with the peakonic patterns change significantly with the effective radial distance from the reference origin outwards. The variations are more pronounced at the center (steep, stiff) than that in the off-centric regions (non-steep, non-stiff). A colormap obtained with the triangulation of the potential-field correlation with the radial distance further confirms the PFS stability behaviors in a qualitative corroboration with the previous predictions reported in the literature. The applicability of our analysis in both the laboratory and astrocosmic contexts is finally indicated.

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BibTeXRIS

Subham Dutta, Pralay Kumar Karmakar. 2022-07-20. Fireball sheath instability. https://doi.org/10.1007/s12036-022-09850-7

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