Influence of electron inertia on gravitational instability of viscous partially ionized radiative quantum plasma

The Jeans self-gravitational instability is studied for dense quantum viscous plasma with Hall term and intrinsic magnetization generated by collective electron spin. The quantum magnetohydrodynamic model is employed to formulate the basic equations of the problem. The dispersion relation is obtained using the normal mode analysis, and further reduced for both transverse and longitudinal modes of propagation. The transverse mode of propagation is found to be unaffected by the Hall term but affected by quantum effect, viscosity, and magnetization parameters. The Jeans criterion of instability in the transverse direction is modified by Alfven velocity, magnetization parameter, and quantum effect. The non-gravitating magnetized mode is obtained in the longitudinal direction, which is modified by Hall parameter and is not affected by quantum term, whereas the gravitational mode is unaffected by the magnetization parameter but affected by viscosity and quantum parameters. It is observed that the Jeans condition of instability is affected by the quantum term. The growth rate of Jeans instability is plotted for various values of magnetization, quantum, and viscosity parameters of the quantum plasma medium.

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Gravitational instability of partially ionized molecular clouds

Journal of Plasma Physics ◽

10.1017/s0022377806006295 ◽

2007 ◽

Vol 73 (6) ◽

pp. 831-838 ◽

Cited By ~ 3

Author(s):

A.C. BORAH ◽

A.K. SEN

Keyword(s):

Molecular Clouds ◽

Radial Direction ◽

Gravitational Instability ◽

Normal Mode Analysis ◽

Equations Of Motion ◽

Local Approximation ◽

Mode Analysis ◽

Interstellar Clouds ◽

Electrons And Ions ◽

Partially Ionized

AbstractStars are formed as a result of the gravitational (Jeans) collapse of dense clumps in interstellar clouds. These clouds are partially ionized by nearby ionizing sources. We investigate the gravitational instability in such molecular clouds considering the non-Boltzmannian distribution for electrons and ions, which is more realistic than the Boltzmannian distribution. Assuming the perturbation (fluctuation) response in a radial direction as a mathematical analogue of the x-direction in the plane geometry approximation in the form f ∼ exp(ikx–iωt), the equations of motion for different species of the multi-fluid plasma are linearized. Jeans' swindle is used as a local approximation for the equilibrium and the dispersion relation is derived by usual normal mode analysis. Then, an analytical solution to the dispersion equation with an explanation of the effects on star formation is given.

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Gravitational instability of a rotating partially-ionized plasma carrying a uniform magnetic field with hall effect

Astrophysics and Space Science ◽

10.1007/bf00613206 ◽

1993 ◽

Vol 199 (2) ◽

pp. 323-331 ◽

Cited By ~ 4

Author(s):

Vinod Kumar ◽

Nagendra Kumar ◽

Krishna M. Srivastava ◽

R. C. Mittal

Keyword(s):

Magnetic Field ◽

Hall Effect ◽

Uniform Magnetic Field ◽

Gravitational Instability ◽

Partially Ionized

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Effect of rotation on gravitational instability of optically thick magnetized quantum plasma in the presence of radiation

10.1063/1.5033236 ◽

2018 ◽

Author(s):

A. Kumar ◽

R. K. Pensia

Keyword(s):

Gravitational Instability ◽

Quantum Plasma

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Gravitational instability of rotating magnetized quantum anisotropic plasma

Journal of Plasma Physics ◽

10.1017/s0022377817000162 ◽

2017 ◽

Vol 83 (2) ◽

Cited By ~ 2

Author(s):

Shraddha Argal ◽

Anita Tiwari ◽

R. P. Prajapati ◽

P. K. Sharma

Keyword(s):

Gravitational Instability ◽

Fluid Model ◽

Longitudinal Mode ◽

Instability Criterion ◽

Quantum Plasma ◽

Uniform Rotation ◽

Longitudinal Modes ◽

Stabilizing Effect ◽

Jeans Instability ◽

Transverse Propagation

The present problem deals with the study of gravitational (Jeans) instability of magnetized, rotating, anisotropic plasmas considering quantum effects. The basic equations of the considered system are constructed using combined Chew–Goldberger–Low (CGL) fluid model and quantum magnetohydrodynamic (QMHD) fluid model. A dispersion relation is obtained using the normal mode technique which is discussed for transverse and longitudinal modes of propagation. It is found that a rotating quantum plasma influences the gravitational mode in transverse propagation but not in longitudinal propagation. The presence of rotation decreases the critical wavenumber and it has a stabilizing effect on the Jeans instability criterion of magnetized quantum plasma in transverse propagation. The firehose instability is unaffected due to the presence of uniform rotation and quantum corrections. We observe from the numerical analysis that region of instability and critical Jeans wavenumber are both decreased due to the presence of uniform rotation. The stabilizing influence of uniform rotation is observed for magnetized, rotating, anisotropic plasmas in the presence of quantum correction. In the case of a longitudinal mode of propagation we found the Jeans instability criterion is not affected by rotation. The quantum diffraction term has a stabilizing effect on the growth rate of the Jeans instability when the wave propagates along the direction of the magnetic field.

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