Degenerate Plasma Research Articles

Linear and Nonlinear Spherically Symmetric Perturbation in Astrophysical Compact Objects

A degenerate quantum plasma system (DQPS) consisting of arbitrary number of degenerate light (electron, proton, neutron, etc.) and heavy (light nuclei/element, heavy nuclei/element, etc.) particle species is considered to investigate the spherically symmetric perturbation (both linear and nonlinear) of self-gravitational field. The fundamental characteristics (amplitude, width, etc.) of small amplitude self-gravitational potential structures, which are found to be formed in the considered plasma system, are examined by the reductive perturbation technique. The derivation and numerical analysis of the modified Korteweg-de Vries (mKdV) equation are obtained. The analytical results are applied in astrophysical compact objects like white dwarfs and neutron stars, which are the examples of DQPS. Journal of Engineering Science 13(1), 2022, 97-104

Ion-acoustic multisolitons in pair-ion plasmas containing degenerate electrons: overtaking collisions at critical compositions

Overtaking collisions of ion-acoustic (IA) solitons are examined in an unmagnetized pair-ion plasma containing degenerate electrons. A Korteweg-de Vries (KdV) equation governing nonlinear IA solitons in such a degenerate plasma model is obtained. At critical compositions, the nonlinear coefficient of the KdV equation vanishes. Therefore, a modified KdV (mKdV) equation describing nonlinear IA solitons in the degenerate plasma model has been derived by extending the analytic analysis to this critical case. Hirota’s bilinear method has been applied to obtain the multisolitons solution and their corresponding phase shifts in these two situations. For an in-depth analysis, we investigated the dynamics of two solitons of the same polarity and opposite polarities resulting from the overtaking collision for discrete times. In particular, the phase shifts are obtained for the first time at critical components in degenerate plasmas. In these two cases, it is found that the magnitude of the phase shifts due to the overtaking interaction of two solitons increases with increasing the negative ion-to-positive ion number density ratio. The present study may help explain the properties of nonlinear waves in white dwarfs that support the propagation of solitons.

Variation of average Lorentz factors in degenerate and non-degenerate relativistic plasmas

Variation of average Lorentz factors in degenerate and non-degenerate relativistic plasmas

Bifurcation Analysis of EAWs in Degenerate Astrophysical Plasma: Chaos and Multistability

Bifurcation analysis and dynamical system studies are carried out to find the stability regime and chaotic scenario in electron acoustic waves in relativistic degenerate plasma. We have obtained the quantum hydrodynamic model and obtain the Korteweg–de Vries equation describing the nature and characteristics of solitary structures. The amplitude modulated envelop soliton formation due to external perturbations has been studied by analyzing the nonlinear Schrodinger equation. Further to study the stability factors and the parametric range for such stability, the dynamical system is studied and bifurcation analysis has been carried out. The chaotic behavior of the system is studied through largest Lyapunov exponent (LLE). This work will find application in theoretically predicting the stable modes in many solar plasma and stellar plasma applications and in laser plasma in future.

Semi-Lagrangian Method to Study Nonlinear Electrostatic Waves in Quantum Plasma

In this work, we used the semi-Lagrangian method and the Vlasov code to study the instabilities in a quantum plasma with 1-D temperature anisotropy. Taking the Fermi-Dirac type of distribution function (DF) and using the semi-Lagrangian Vlasov code, we studied the gradual evolution of density and kinetic energy in a degenerate plasma with quantum effects. In this collisionless plasma, adiabatic compression will be along the direction of wave propagation and will lead to temperature anisotropy of the electron distribution that varies along the direction of wave propagation. The findings will find application for dense plasma at finite temperature as in laser-produced plasmas, fusion plasma, as well as solar plasmas.

Formation of Nonlinear Stationary Structures in Ionospheric Plasma

Solar radiation, along with cosmic radiation, ionizes the Earth's atmosphere and creates a dense layer known as the ionosphere. By considering weakly relativistic degenerate plasma in the planetary ionosphere, we have studied the formation and nature of the solitary structure, electrostatic double layers (DLs), and so on. As we have considered weak relativistic degeneracy, only electrons get accelerated and are the key to stationary structures. We have implemented Sagdeev's pseudopotential method, standard Gardner equation, and accordingly identified regimes where the solitary formation and DLs may be observed. We have studied the parametric influences on solitons and DLs. Furthermore, we extended our investigation to the oscillatory Rossby solitons in the ionospheric plasma. The results may help interpret many high-energy atmospheric observations in the ionospheric plasma.

Relativistic hydrodynamic model with the average reverse gamma factor evolution for the degenerate plasmas: High-density ion-acoustic solitons

High-density low-temperature plasmas with degenerate species are considered in the limit of high Fermi velocities close to the speed of light. The small amplitude ion-acoustic solitons are studied in this regime. The analysis presented here is based on a relativistic hydrodynamic model with the average reverse gamma factor evolution consisting of the equations for the evolution of the functions such as the concentration, the velocity field, the average reverse relativistic gamma factor, and the flux of the reverse relativistic gamma factor, which are considered as main hydrodynamic variables. Justification of the suggested model via comparison of the hydrodynamic results with the result of application of the relativistic Vlasov kinetic equation is made in the linear approximation.

Electron-acoustic solitons in dense electron–positron–ion plasma: Degenerate relativistic enthalpy function

An enthalpy function Hj∝1+ηj2 is deduced from the density of states for degenerate relativistic charged particulate. Here ηj=pj/mjc2 stands for the relativistic factor, pjmj is the Fermi momentum (mass) for the jth degenerate relativistic species and c designates the vacuum speed of light. The enthalpy function reduces the results Weinberg (1972), Lee and Cheong (2007) obtained for the nondegenerate nonrelativistic (NR) and ultrarelativistic (UR) fluids. The linear and nonlinear propagation characteristics of the electron-acoustic (EA) solitons are examined for dense electron–positron–ion (EPI) plasma that comprises degenerate relativistic electrons/positrons and non-degenerate ions. By using Hj and with the aid of the relativistic hydrodynamic equations, a linear dispersion relation for the EA waves is derived that admits the evolution of the fast and slow electron-acoustic (FEA/SEA) excitations. For the nonlinear EA waves, a Korteweg–de Vries (KdV) equation is obtained; numerical analysis reveals that the FEA mode may ensue in the solitary potential. The propagation of the SEA solitons is forbidden as it suffers from a negative phase dispersion effect. At a relatively low concentration of positrons, the EPI plasma may admit the evolution of electron–holes and therefore, give rise to the compressive FEA solitons. This investigation is important for understanding localized excitations in degenerate relativistic plasmas, as that are relevant in white dwarfs, neutron stars, and high-energy density facilities.

Review of heavy-nucleus-acoustic nonlinear structures in cold degenerate plasmas

Review of heavy-nucleus-acoustic nonlinear structures in cold degenerate plasmas

Coupling and Instability of Electrostatic Waves in Spin Magnetized Degenerate Plasmas

In this article, we study the coupling of low-frequency electrostatic waves in the electron-ion and the electron-ion-beam-spin quantum plasmas. The quantum effect of electrons are introduced via separate spin evolution-quantum hydrodynamic (SSE-QHD) model while the ion dynamics is governed by classical fluid equations. In the case of electron-ion plasma, it is found that the quantum effects shift both the coupling domain and the phase velocities of coupled waves. Furthermore, the coupling is observed to be strong at small propagation angles. In the beam interacting system, two coupling domains occur corresponding to small and large <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k$ </tex-math></inline-formula> -values. In the first domain beam mode excites the ion cyclotron (IC) wave and moves with constant phase velocity while in the second domain it gains energy from the ion acoustic (IA) mode and travels with increasing phase velocity. In addition, the beam parameters affect both the coupling domain and the phase velocity. The presence of beam in electron-ion plasma drives the IC mode unstable. The beam parameters, the spin, and the obliqueness affect the instability. Our findings may be helpful in understanding the energy exchange of plasma waves via coupling phenomenon in degenerate plasma systems.

Stability and evolution of ion-acoustic solitons in strongly coupled relativistic degenerate pair plasmas

Stability and evolution of ion-acoustic solitons in strongly coupled relativistic degenerate pair plasmas

Overtaking interactions of nonlinear ultra-low frequency multi-shock structures in non-relativistic and ultra-relativistic degenerate plasmas

A Burgers’ equation (BE) is obtained to examine the overtaking interactions of nonlinear ultra-low frequency (ULF) shock waves, in two cases, in non-relativistic and ultra-relativistic degenerate plasmas consisting of inertial mobile heavy-ion fluid and inertialess light ions and electrons. The Cole–Hopf transformation and the exponential function have been employed to obtain nonlinear ULF multi-shock structures. From the careful analysis, it is found that the overtaking collisions of ULF multi-shock waves and their electric fields are significantly modified with the influence of heavy-ion kinematic viscosity. It is shown that the amplitude and the steepness of ULF multi-shock waves increase with the decrease in the light-to-heavy ion density ratio. Numerical simulations of overtaking collisions are used to shed light on the dynamics of ULF multi-shock waves in astrophysical plasmas such as white dwarf stars.

Overtaking Interactions of Multi-Ion Acoustic Shock Waves in a Magnetized Degenerate Plasma: An Application in White Dwarfs

Overtaking interactions are examined of multi-ion acoustic shock waves in magnetized degenerate quantum plasmas comprising inertial non-relativistic heavy and light ions having positive charges ultra-relativistic degenerate inertialess electrons. A Burgers’ equation governs the nonlinear excitation of multi-ion acoustic shock waves in a plasma model at hand. The Cole-Hopf transformation and the exponential function have been used to study the overtaking interactions of multi-ion acoustic shock waves in two modes (i.e., the fast and the slow modes). Numerically, the compressive ion-acoustic shock waves exist for the fast mode, but the rarefactive ion-acoustic shock waves exist for the slow mode. A numerical simulation demonstrates that the overtaking interactions of multi-ion acoustic shock waves and their electric fields are remarkably modified with the effectiveness of the charge states of heavy ions and light ions. Furthermore, the amplitude and the steepness of multi-ion acoustic shock waves increase with the decrease in the directional cosines of the multi-ion acoustic shock waves vector along the z-axis. Numerical simulations of overtaking interaction are employed to significantly highlight the physical features of multi-ion acoustic shock waves in astrophysical situations such as white dwarfs and neutron stars.

NANOENERGY AND NANOTECHNOLOGY OF THE NEW TECHNOLOGICAL PARADIGMSAVING HUMANITY FROM POISONING THE PLANET EARTH.

When using existing industrial technologies, a very high price of energy resources remains, due to their imperfection and the need to heat almost all fixed assets, as well as a lack of resources to restore the disturbed balance between the biosphere and the technosphere, caused by the lack of highly efficient cycle technologies: mining, production of useful products from them, rational use of these products and, finally, its utilization. Of what is extracted from the land, 95% goes either to intermediate consumption or buried. The world is in a state where the environmental damage of technology has exceeded the capabilities of the Earth. With the preservation of existing industrial technologies, resources in the world are becoming less and less, humanity has nothing to pay for cleaning and restoring the environment. Only new technologies and new resources will save humanity from collapse. The solution lies in finding a new alternative, renewable, harmless and sustainable source of energy, the very use of which is an industry for the processing and destruction of created waste - recycling, comparable in volume with the entire transport and energy complex. In this case, it is possible to stabilize the world at the current level of consumption and implement the idea of sustainable development. &#x0D; This article, based on the results of fifty years of work of author on development of breakthrough energy technologies in theory and practice of a non-ideal, close to non- degenerate plasma, started with PhD in Physics &amp; Mathematics A.A. Rumiantsev who, unfortunately, passed away in 1990. Author predicted and confirmed the existence of a fundamentally new state of physical matter - quantum plasma nanocondensate - liquefied plasma, combining the properties inherent in standard liquid and ionized plasma - a fundamentally new, effective, and harmless energy source, the use of which helps reduce the pollution caused by waste. Purification of planet Earth, which has been contaminated to the limit, in some areas of which gas contamination, slagging, and municipal waste exceed all permissible norms, will lead to a boost in the immune system of the population, which will make it possible for humans to exist safely.

Anomalous skin effects and energy transfer of R-L waves in relativistic partially degenerate plasma

Abstract On utilizing the kinetic model for transverse permittivity in a weakly magnetized electron plasma, the two particular phenomena of wave-particle interaction i.e., anomalous skin depth and energy transfer are examined in circularly polarized R- and L-waves within relativistic Fermi–Dirac distributed plasmas. Further, the non-trivial influential roles by some salient parameters i.e., relativistic thermal T m 0 c 2 &gt; 0 $\left(\frac{T}{{m}_{0}{c}^{2}} &gt; 0\right)$ , γ (from bulk flow such that γ &gt; 1), degeneracy (due to μ T $\frac{\mu }{T}$ ) and weak ambient magnetic field (B 0), on above mentioned wave phenomena, are also analyzed. The derived results, in the form of polylog function, delineate the inverse relation between spatial damping and energy flux transportation regarding the variation in above mentioned dominant parameters. It is noticed that the relativistic thermal parameter serve as a penetration depth elevator for R- and L-waves and so they transfer energy slowly, whereas the degeneracy and relativistic γ parameters submerse the depth and cause upraise in energy transfer. Moreover, the increase in weak ambient magnetic field reduces the penetration depth of R-wave that delivers its energy rapidly, whereas it enlarges the penetration depth of L-wave which causes slow delivery of its energy. The results discussed (both analytically and graphically) are justifiably confirmed with previous illustrative reports. Applicability of the analysis relevant in partially degenerate regions both in space (e.g., in white dwarfs and young brown dwarf) and laboratory (e.g., in laser plasma interaction, liquid metals, inertial confinement fusion (ICF) and Fermi gas of metals) plasmas.

Arbitrary-amplitude self-gravitational solitary potential in a degenerate quantum plasma system

Arbitrary-amplitude self-gravitational solitary potential in a degenerate quantum plasma system

The methods of thermal field theory for degenerate quantum plasmas in astrophysical compact objects

In the study of degenerate plasmas contained within compact astrophysical objects, both special relativity and general relativity play important roles. After reviewing the existing treatment in the literature, here we employ the methods of relativistic thermal quantum field theory to compute the equation of states of degenerate matter for compact astrophysical objects such as the white dwarfs and the neutron stars. In particular, we compute the equation of states that include leading order corrections due to the finite temperature, the fine-structure constant as well as the effect of gravitational time dilation. We show that the fine-structure constant correction remains well-defined even in the non-relativistic regime in contrast to the existing treatment in the literature.

Novel features of electromagnetic waves in an isotropic degenerate electron-ion plasma

Within the framework of kinetic theory, the nonlinear interaction of electromagnetic waves (EMWs) with a degenerate electron-ion plasma is studied to account for the electron quantum mechanical effects. For this purpose, a specific quantum regime is considered, for which the degenerate electron Fermi velocity is assumed to be of the order of the group velocity of EMWs. This eventually leads to the existence of a nonlinear Landau damping rate for the EMWs in the presence of electron ponderomotive force. The electron–ion density oscillations may have arisen from the nonlinear interaction of EMWs, leading to a new type of nonlinear Schrödinger equation in terms of a complex amplitude for electromagnetic pump waves. The profiles of nonlinear damping rates reveal that EMWs become less damped for increasing the quantum tunneling effects. The electrostatic response of the linear electrostatic waves is also investigated and derived from a linear dispersion for the ion-acoustic damping rate. The latter is a direct function of the electron Fermi speed and does not rely on the Bohm tunneling effect. The obtained results are numerically analyzed for two microwaves of different harmonics in the context of nonrelativistic astrophysical dense plasma environments, e.g. white dwarfs, where the electron quantum corrections cannot be ignored.

Impacts of Strongly Magnetized Degenerate Plasma on the Electron-capture Rates

The strongly magnetized degenerate astrophysical plasma is investigated.Arelativistic Hartree self-consistent field method is applied to calculate the screening potential. A profile froma15M⊙ core collapsing supernova (SN) progenitor is applied to evaluate the electron-capture rates of 54Fe. It is found that the screening potential at high field is enhanced compared with the previous study. If the field is high enough and only the lowest Landau level is allowed, two orders of magnitude reduction of the capture rates are found in the high-density region. Such deviations of the electron capture rates are essential since the rates determine the neutron richness of the progenitor model as well as the iron core mass, which are crucial for MHD-Jet SNe explosion calculation.

Low frequency Compressional modes in degenerate semiconductor plasmas

Properties of low frequency compressional electromagnetic wave pulse in a magnetized semiconductor hole-electron plasma, are investigated. The quantum mechanical effects such as Fermi pressure, quantum tunneling and exchange-correlation potential of inertialess electrons, inertial holes and stationary charged ion particulates are considered in the presence of the magnetic field. A new type of dispersion relation is derived for low-frequency compressional waves by employing quantum magneto-hydrodynamic model and Maxwell equations; the dispersion relation is then analyzed for parallel, perpendicular and oblique propagation of compressional electromagnetic wave pulse to the external magnetic field direction. We have analyzed the obtained dispersion relations numerically, for different semiconductor plasma such as GaAs, GaSb and, GaN, the graphs shows that the frequency of compressional electromagnetic wave pulse decreases with increase of electron-hole density concentration, whereas the frequency increases with the increase of angle of propagation compressional electromagnetic wave pulse. Our results are applicable to understanding the dynamics of semiconductor plasma to produce high power, high band-width devices in contrast to the existing gas plasma devices. Keywords: degenerate semiconductor plasma, quantum mechanical effects, compression electromagnetic wave, gas plasma device.