Influence of ionization and ion loss on radiative and gravitational instabilities of inhomogeneous plasma with dust polarization force

Abstract

In the present work, the radiative condensation and gravitational instabilities of inhomogeneous self-gravitating partially ionized dusty plasma have been studied with dust polarization force, ionization and recombination. The basic equations are constructed using four fluid model. The full dynamics of charged dust grains, ions and neutral species are employed considering the electrons as inertialess which have finite thermal conductivity and radiative cooling. The general dispersion relation is derived and discussed for different dusty plasma situations. It is found that the instability conditions are greatly affected due to the polarization force and recombination. Specifically, it is pointed out that the polarization force enhances the growth rate of both the radiative and gravitational instability while the recombination frequency decreases it. Both the parameters have influencing role in short wavelength regime. The e-folding times are calculated for maximum growth rates of gravitational and radiative condensation instabilities. The present work is applicable for study of interstellar molecular clouds and therefore the corresponding free fall time of molecular clouds is also presented.

Jeans analysis with κ-deformed Kaniadakis distribution in f (R) gravity

“…In recent decades, Jeans analysis play an important role in the explanation of the formation and evolution of gravitational structures, it has become a hot topic in the field of astrophysics [1][2][3][4][5][6], plasma physics [7][8][9][10][11][12][13][14][15][16], and complex fluid community [17][18][19]. In the self-gravitating system, Jeans wave-length and Jeans mass are important parameters to determine whether a system is stable or not, when the perturbations wave-length greater than Jeans wave-length or system mass exceed its Jeans mass, the system will become unstable and collapse due to its own gravitation [20].…”

The effect of dust charge-gradient and dust polarization forces on the Jeans instability in a collisional magnetized dusty plasma

“…It describes the fact that during the collision of the dust grains the dust collisional momentum exchange which causes a dissipative process. This dissipation often takes place consuming the available free gravitational energy resulting in the reduced growth rate [50]. The analysis of the graph depicts that as the normalized wave number k* advances, first the growth rate of instability decreases and then at a particular value of k* it becomes zero for all the three different values of dust collision frequency on the same wave number.…”

“…In a collisional dusty plasma system, the macroscopic length scale of plasma species is comparable to the mean free path and hence the typical dust plasma frequency is also related to the collisional frequency. Such type of system is mostly found in space plasmas [50]. An external stationary magnetic field B 0, 0, ( )is applied in the z-direction.…”

Gravitational instability of dark-baryonic matter systems in f (R) gravity

“…The formation of stars and planets is one of the most basic problems, and also one of the current research hotspots in astrophysics. Jeans analysis is the key to explain the formation and evolution of self-gravitating structures, has become a hot topic in the field of astrophysics [1][2][3][4][5][6][7][8][9], plasma physics [10][11][12][13][14][15][16][17][18][19], and complex fluid community [20][21][22]. Systems where the mutual gravitation exceeds any other external forces are called selfgravitating systems [23], in the self-gravitating system, if its own thermal pressure is insufficient to resist its gravity, the system will become unstable and collapse due to its own gravitation.…”