On the existence of ion-acoustic solitary waves in a gravitating dusty plasma having charge fluctuation

Abstract

Theoretical investigation on the propagation of ion-acoustic waves in an unmagnetized self-gravitating plasma has been made for the existence of solitary waves using the reductive perturbation method. It is observed that nonlinear excitations follow a coupled third-order partial differential equation which is slightly different from the usual case of coupled Korteweg-de Vries (K-dV) system. It appears that the system so deduced is a two-component generalization of the previous one derived by Paul et al. (1999) in which it was shown that ion-acoustic solitary waves can not exist in such system.

Atypical gravito-electrostatic fluctuations in the presence of active ion-inertial dynamics

“…In comparison, the stability analysis presented here, with the effective ion-inertial contribution accounted for in totality, differs from the existing weakly (Verheest & Shukla 1997; Burman & Chowdhury 2002; Paul et al. 2006; Guo et al. 2010; Karmakar 2011) and strongly (Mace & Hellberg 1993; Misra & Chowdhury 2006) nonlinear analyses both fundamentally as well as in observation.…”

“…In conclusion, we propose an atypical hydrodynamic model to study the properties of both the weakly and strongly nonlinear wave dynamics of a gravito-electrostatically coupled collisional cloud of infinite extension. It treats the gravitating massive dust grains with negligible partial ionization and the gravitating ions as inertial fluids, but the thermal electrons as the inertialess Boltzmann-distributed species amid all the significant collisional effects retained on the astrophysical hydrodynamic scales of (Verheest & Shukla 1997;Burman & Chowdhury 2002;Paul et al 2006Paul et al , 2011 13 Nature of eigenmodes Low-frequency gravito-electrostatic eigenmodes on the Jeansian scales Dust-acoustic eigenmodes (Verheest & Shukla 1997;Burman & Chowdhury 2002;Guo et al 2010), Ion-acoustic eigenmode (Paul et al 2006(Paul et al , 2011 (Verheest & Shukla 1997;Burman & Chowdhury 2002;Paul et al 2006Paul et al , 2011Guo et al 2010;Karmakar 2011) 15 Geometrical trajectories Phase trajectories of both the Columbic and Newtonian particles are well studied Not studied (Verheest & Shukla 1997;Burman & Chowdhury 2002;Paul et al 2006;Karmakar 2011) 16 Ratio of eigenmode amplitudes Φ 1 /Ψ 1 ≈ 3.8, for weakly nonlinear modes; and Φ/Ψ ≈ 2.5, for fully nonlinear modes Not shown (Verheest & Shukla 1997;Burman & Chowdhury 2002;Paul et al 2006Paul et al , 2011Guo et al 2010;Karmakar 2011) 17 Spatio-temporal eigenmode patterns to confirm temporal stability Shown for both fluctuation classes Not shown (Verheest & Shukla 1997;Burman & Chowdhury 2002;Paul et al 2006Paul et al , 2011…”

“…2005; Paul et al. 2006; Shalini & Saini 2015). It is indeed questionable to treat the heavy ions as Boltzmanian particles in the analyses, as is common practice.…”

“…It is seen that space and astrophysical plasmas consist of a huge number of massive ions in addition to dust grains and gas-phase electrons (Mace & Hellberg 1993). The ion-inertia, although weak but finite in comparison with the massive grains (m i /m d ∼ 10 −15 -10 −8 ), might have some dominant interesting influence on the excitation processes and associated evolutionary dynamics of the normal modes in wide, spatially extended systems (Mace & Hellberg 1993;Pandey & Dwivedi 1996;Merlino & D'Angelo 2005;Misra et al 2005;Paul et al 2006;Shalini & Saini 2015). It is indeed questionable to treat the heavy ions as Boltzmanian particles in the analyses, as is common practice.…”

Nonlinear gravito-electrostatic waves in self-gravitating complex plasma in presence of ion-drag effects

“…Such structures, to name a few, include stars, stellar rings, planets, planetesimals, planetary rings, cometary tails, clusters, etc. (Mace and Hellberg 1993;Mamun and Shukla 2002;Shukla and Mamun 2003;Paul et al 2006;Karmakar et al 2012).…”