Bimodal pair f-KdV dynamics in star-forming clouds

Abstract

A theoretical formalism for investigating the bimodal conjugational mode dynamics of hybrid source, dictated by a unique pair of forced Korteweg-de Vries (f-KdV) equations in a complex turbo-magnetized star-forming cloud, is reported. It uses a standard multi-scale analysis executed over the cloud-governing equations in a closure form to derive the conjugated pair f-KdV system. We numerically see the structural features of two distinctive classes of eigenmode patterns stemming from the conjoint gravito-electrostatic interplay. The electrostatic compressive monotonic aperiodic shock-like patterns and gravitational compressive non-monotonic oscillatory shock-like structures are excitable. It is specifically revealed that the constitutive grain-charge (grain-mass) acts as electrostatic stabilizer (gravitational destabilizer) against the global cloud collapse dynamics. The basic features of the nonlinear coherent structures are confirmed in systematic phase-plane landscapes, indicating electrostatic irregular non-homoclinic open trajectories and gravitational atypical non-chaotic homoclinic fixed-point attractors. The relevance in the real astro-cosmic scenarios of the early phases of structure formation via wave-driven fluid-accretive transport processes is summarily emphasized.

Solitary-train dynamics in viscoelastic nonthermal astroplasmas

“…The nonlinear wave patterns investigated here can play an important role in producing dense phases in interstellar media via wave-induced material accretivedecretive processes. This is how the results can be of immense significance in conceiving the dynamic initiation processes responsible for conversion of viscoelastic astrofluids into stellesimals, planetesimals and other gravitationally bounded equilibrium structures in different realistic astroplasma conditions [12][13][14][15]18,19]. This, in fact, is trigerred spontaneously via dynamic nonlocal self-gravitational cloud fragmentation phenomenology.…”

“…A nonlinear logatropic barotropic law to take care of the fluid turbulence effects is considered amid thermal fluctuations at a significant level [9]. The fluid turbulence arises due to the existence of irregular and chaotic behaviour of the vorticity associated with the microscopic particle motion amid large-scale gravity-driven equilibrium gradient forces [19]. The bulk thermal convective transport in the mean ionic fluid approach is modelled in the fabric of a proper construction of the heat flow equation.…”

Bimodal instability dynamics in nonthermal complex tridust astroclouds towards structure formation

“…(a) E-mail: pkk@tezu.ernet.in This mode spontaneously triggers the initialization of the dense phases of the interstellar cloud matter needed for the formation of bounded structures, such as stars, planets, and so forth [12][13][14][15][16][17][18]. The basic condition required for the bounded astrostructures to form, resulting from the mutualistic gravito-electrostatic force balancing is that the constitutive dust grain specific charge must possess a critical gravito-electrostatically compatible value, (q d /m d ) ∼ √ G, where G = 6.67 × 10 −11 N m 2 kg −2 is the universal gravitational (Newtonian coupling) constant [6,7].…”

“…It also ignores the mechanisms responsible for the grain destruction, such as the photodesorption by the UV light, sublimation, cosmic ray sputtering, etc. The net pressures associated with the constitutive dust fluids are modelled with the help of the Larson logatropic equation of state comprising of an isothermal component for the fluid thermal pressure (linear in density) and a logatropic component for the fluid turbulence pressure (nonlinear in density) effects [5,13,25]. The electrodynamical response frequency of the electrons and ions with the conventional asymptotic inertial mass scaling, m e /m d < m i /m d ∼ 10 −20 → 0, in the interstellar diffuse matter is very high in comparison with that of the selfgravitating dust grains [6,17].…”

“…The closure is in the electro-gravitational Poisson equations describing the potential distributions developed at the cost of local charge and matter density fields in a closed coupled form, respectively. Such heteropolar grainy plasma conditions caused by the different dust-electrification processes could be realized in large-scale space and astronomical plasma environs, such as interstellar space, interplanetary medium, planetary rings, molecular clouds, cometary plasma medium, and so forth [3][4][5]13,17].…”