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Title: Star formation through thermal instability of radiative plasma with finite electron inertia and finite Larmor radius corrections

Abstract

I have studied the effects of finite electron inertia, finite ion Larmor radius (FLR) corrections, and radiative heat-loss function on the thermal instability of an infinite homogeneous, viscous plasma incorporating the effect of thermal conductivity for star formation in interstellar medium (ISM). A general dispersion relation is derived using the normal mode analysis method with the help of relevant linearized perturbation equations of the problem. The wave propagation is discussed for longitudinal and transverse directions to the external magnetic field and the conditions of modified thermal instabilities and stabilities are discussed in different cases. We find that the thermal instability criterion is get modified into radiative instability criterion by inclusion of radiative heat-loss functions with thermal conductivity. The viscosity of medium removes the effect of FLR corrections from the condition of radiative instability. Numerical calculation shows stabilizing effect of heat-loss function, viscosity and FLR corrections, and destabilizing effect of finite electron inertia on the thermal instability. Results carried out in this paper shows that stars are formed in interstellar medium mainly due to thermal instability.

Authors:
 [1]
  1. Department of Physics, Mahakal Institute of Technology, Ujjain-456664, Madhya Pradesh (India)
Publication Date:
OSTI Identifier:
22611370
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CORRECTIONS; DISPERSION RELATIONS; DISPERSIONS; DISTURBANCES; ELECTRONS; HEAT LOSSES; INSTABILITY; INTERSTELLAR SPACE; LARMOR RADIUS; MAGNETIC FIELDS; MOMENT OF INERTIA; NORMAL-MODE ANALYSIS; PERTURBATION THEORY; PLASMA; STABILITY; STARS; THERMAL CONDUCTIVITY; VISCOSITY; WAVE PROPAGATION

Citation Formats

Kaothekar, Sachin, E-mail: sackaothekar@gmail.com. Star formation through thermal instability of radiative plasma with finite electron inertia and finite Larmor radius corrections. United States: N. p., 2016. Web. doi:10.1063/1.4961991.
Kaothekar, Sachin, E-mail: sackaothekar@gmail.com. Star formation through thermal instability of radiative plasma with finite electron inertia and finite Larmor radius corrections. United States. doi:10.1063/1.4961991.
Kaothekar, Sachin, E-mail: sackaothekar@gmail.com. 2016. "Star formation through thermal instability of radiative plasma with finite electron inertia and finite Larmor radius corrections". United States. doi:10.1063/1.4961991.
@article{osti_22611370,
title = {Star formation through thermal instability of radiative plasma with finite electron inertia and finite Larmor radius corrections},
author = {Kaothekar, Sachin, E-mail: sackaothekar@gmail.com},
abstractNote = {I have studied the effects of finite electron inertia, finite ion Larmor radius (FLR) corrections, and radiative heat-loss function on the thermal instability of an infinite homogeneous, viscous plasma incorporating the effect of thermal conductivity for star formation in interstellar medium (ISM). A general dispersion relation is derived using the normal mode analysis method with the help of relevant linearized perturbation equations of the problem. The wave propagation is discussed for longitudinal and transverse directions to the external magnetic field and the conditions of modified thermal instabilities and stabilities are discussed in different cases. We find that the thermal instability criterion is get modified into radiative instability criterion by inclusion of radiative heat-loss functions with thermal conductivity. The viscosity of medium removes the effect of FLR corrections from the condition of radiative instability. Numerical calculation shows stabilizing effect of heat-loss function, viscosity and FLR corrections, and destabilizing effect of finite electron inertia on the thermal instability. Results carried out in this paper shows that stars are formed in interstellar medium mainly due to thermal instability.},
doi = {10.1063/1.4961991},
journal = {AIP Advances},
number = 8,
volume = 6,
place = {United States},
year = 2016,
month = 8
}
  • The influence of finite Larmor radius (FLR) effects on the Jeans instability of infinitely conducting homogeneous quantum plasma is investigated. The quantum magnetohydrodynamic (QMHD) model is used to formulate the problem. The contribution of FLR is incorporated to the QMHD set of equations in the present analysis. The general dispersion relation is obtained analytically using the normal mode analysis technique which is modified due to the contribution of FLR corrections. From general dispersion relation, the condition of instability is obtained and it is found that Jeans condition is modified due to quantum effect. The general dispersion relation is reduced formore » both transverse and longitudinal mode of propagations. The condition of gravitational instability is modified due to the presence of both FLR and quantum corrections in the transverse mode of propagation. In longitudinal case, it is found to be unaffected by the FLR effects but modified due to the quantum corrections. The growth rate of Jeans instability is discussed numerically for various values of quantum and FLR corrections of the medium. It is found that the quantum parameter and FLR effects have stabilizing influence on the growth rate of instability of the system.« less
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