Low frequency modes and instability analysis in non-thermal dusty magnetoplasma considering dust charge fluctuation and polarization force

Abstract

The effect of non-thermal ion population on self-gravitational instability of magnetized dusty plasma considering electrons are in Maxwell-Boltzmann distribution has been investigated. The dust dynamics is described including polarization force, thermal velocity, and charge fluctuation dust. The modified general dispersion relation has been derived including non-thermal ion population, polarization force, and dust charge fluctuation for self-gravitating dusty plasma system, using the normal mode analysis method. The obtained general dispersion relation is discussed in parallel and perpendicular modes of propagation. The population of non-thermal ion, polarization force and dust charge fluctuation affect the self-gravitational instability criteria in both the modes of propagation while the magnetic field affects the instability criterion only in perpendicular mode of propagation. The domains of instability has been discussed analytically to signify the importance of considered parameters. The stability of the self-gravitating dusty plasma system has been analyzed using Routh-Hurwitz stability criterion. Numerical calculations have been performed to analyze the effects of non-thermal ion population, polarization force, and dust charge fluctuation on the growth rate of self-gravitational instability. The results of the present work can be useful in self-gravitating dusty plasma found in space and the interstellar medium such as the interstellar molecular clouds where non-thermally distributed ions are the species of the plasma matter.

Analysis of radiative gravitational modes in magnetized dusty plasma with non-thermal ion distribution

“…in equation (18). In the absence of the radiative condensation of electrons, the dispersion relation matches with the result given by Sharma et al [21] for self-gravitating magnetized dusty plasma. The dispersion relation (18) resembles the result presented by Khrapak et al [34] for unmagnetized dusty plasma on excluding self-gravitation, dust charge fluctuation, non-thermal ions and the radiative cooling effect from the present work.…”

“…In the absence of dust charge fluctuation, polarization force, non-thermal ions and radiative cooling in dispersion relation (27), the expression turns out to be similar to that given by Rao and Verheest [60], excluding fugacity in that work. If we ignore the radiative cooling in equation (27), the obtained result becomes similar to the dispersion relation given by Sharma et al [21]. Thus, the present work provides the modified dispersion relation for magnetized self-gravitating dusty plasma incorporating dust charge fluctuation, dust polarization force, radiative condensation and nonthermal ion distribution.…”

“…the dust cyclotron mode and radiative self-gravitating mode, move in separate ways independently. The mode found as a result of the magnetic field is identical to the mode given by Sharma et al [21], and the other mode can be written as…”

“…Non-thermal ions have been widely studied in dusty plasmas. Sharma et al [21] have studied the Jeans instability and low frequency modes in dusty plasma, including non-thermal ions, Maxwellian electrons, dust polarization force and charge fluctuation. Considering superthermal electrons and non-thermal ions in dusty plasma, Emamuddin and Mamun [22] have examined dust acoustic shock waves.…”

Effect of polarization and charge gradient forces on the dust acoustic solitary waves

“…When the values of the reduced charge of dust grain are between 2 and 4 within the OML theory 32) in collisionless and unmagnetized plasma, the polarization force and the charge gradient force are of comparable magnitude are discussed by Khrapak et al 33,34) The polarization force represents the deformation of the Debye sphere around dust particles caused by non-uniform plasma. The dust grain will be acted by the polarization force when dust grains immersed in non-uniform plasma and the charge of the dust grain is constant, 24,[35][36][37][38][39][40][41][42][43][44]…”