A theoretical model for electromagnetic characterization of a spherical dust molecular cloud equilibrium structure

B. Borah; P. K. Karmakar

doi:10.1016/j.newast.2015.04.002

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arXiv · 1410.4656

A theoretical model for electromagnetic characterization of a spherical dust molecular cloud equilibrium structure

B. Borah·P. K. Karmakar

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Abstract

A theoretical model is developed to study the equilibrium electromagnetic properties of a spherically symmetric dust molecular cloud (DMC) structure on the Jeans scale. It applies a technique based on the modified Lane-Emden equation (m-LEE). It considers an inhomogeneous distribution of dust grains in field-free hydrodynamic equilibrium configuration within the framework of exact gravito-electrostatic pressure balancing condition. Although weak relative to the massive grains, but finite, the efficacious inertial roles of the thermal species (electrons and ions) are included. A full portrayal of the lowest-order cloud surface boundary (CSB) and associated parameter signatures on the Jeans scale is made numerically for the first time. The multi-order extremization of the m-LEE solutions specifies the CSB at a radial point m relative to the centre. It gets biased negatively due to the interplay of plasma-boundary wall interaction (global) and plasma sheath-sheath coupling (local) processes. The CSB acts as an interfacial transition layer coupling the bounded and unbounded scale-dynamics. The geometrical patterns of the bi-scale plasma coupling are elaborately analyzed. Application of the proposed technique to neutron stars, other observed DMCs and double layers is stressed together with possible future expansion.

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B. Borah, P. K. Karmakar. 2014-10-17. A theoretical model for electromagnetic characterization of a spherical dust molecular cloud equilibrium structure. https://doi.org/10.1016/j.newast.2015.04.002

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