Variation of average Lorentz factors in degenerate and non-degenerate relativistic plasmas (original) (raw)

Study of the O-mode in a relativistic degenerate electron plasma

Plasma Science and Technology, 2017

Using the linearized relativistic Vlasov-Maxwell equations, a generalized expression for the plasma conductivity tensor is derived. The dispersion relation for the O-mode in a relativistic degenerate electron plasma is investigated by employing the Fermi-Dirac distribution function. The propagation characteristics of the O-mode (cut offs, resonances, propagation regimes, harmonic structure) are examined by using specific values of the density and the magnetic field that correspond to different relativistic dense environments. Further, it is observed that due to the relativistic effects the cut off and the resonance points are shifted to low frequency values, as a result the propagation regime is reduced. The dispersion relations for the non-relativistic and the ultra-relativistic limits are also presented.

Kinetic theory of the plasma-dynamical modes and the transport coefficients of a relativistic plasma

Physica A: Statistical Mechanics and its Applications, 1975

The kinetic equation of an inhomogeneous relativistic plasma, consisting of an electron gas and a radiation field, is studied with particular regard to its eigenvalues in the hydrodynamical limit. The treatment is classical for the particles and quantum-mechanical for the field oscillators. After a suitable regularization, the eigenvalues are obtained by a perturbation theory through second order in the strength of the gradients. It is shown that these eigenvalues are in exact correspondence with the macroscopic relativistic plasma-dynamical modes. The important role played by the Vlassov operator in building up the peculiar structure of these modes is underlined. From a comparison of the macroscopic and microscopic eigenvalues we obtain general expressions for the thermal conductivity, the shear viscosity and the bulk viscosity of a relativistic plasma. The contribution of the radiation field to these quantities is a noteworthy feature of these expressions.

On the dispersion characteristics of extraordinary mode in a relativistic fully degenerate electron plasma

Physics of Plasmas, 2018

The study of relativistic degenerate plasmas is important in many astrophysical and laboratory environments. Using linearized relativistic Vlasov–Maxwell equations, a generalized expression for the plasma conductivity tensor is derived. Employing Fermi-Dirac distribution at zero temperature, the dispersion relation of the extraordinary mode in a relativistic degenerate electron plasma is investigated. The propagation characteristics are examined in different relativistic density ranges. The shifting of cutoff points due to relativistic effects is observed analytically and graphically. Non-relativistic and ultra-relativistic limiting cases are also presented.

Relativistic Scalar Plasma

Physical Review, 1968

The behavior of the relativistic scalar plasma in the Viasov approximation is analyzed. Equilibrium properties are discussed (equation of state, Debye-Huckel law"phase transitions). A dispersion relation for the propagation of a small disturbance is derived. Hydrodynamical equations are obtained. A number of ambiguities inherent in the theory are emphasized and discussed.

Lorentz ratio of quantum plasmas

Physics of Plasmas, 1994

A quantum collective approach is developed to investigate linear transport properties of a system of highly degenerate weakly coupled electrons and strongly coupled semiclassical ions. The basic formalism rests upon suitable extention of the Boltzmann-Bloch quantum transport equation. The model considers electron-ion (e-i) and electron-electron (e-e) collisions in a unified scheme of both long-and short-range Coulomb interactions. The e-e collisions contribute to the thermal conductivity calculation in the low coupling regime. Even though they can be insignificant for strongly coupled systems, the extensively used Lorentz gas approximation cannot be justified for plasmas of astrophysical interests. It is shown that the Lorentz ratio of high-density plasma may exhibit substantial negative deviation from the ideal Sommerfeld value, due to some nonidealities, such as e-e interaction and quantum effects. Results are presented under analytical and compact forms allowing numerical applications, as well as comparisons with existing theories.

Relativistic Quantum Response of a Strongly Magnetised Plasma. I. Mildly Relativistic Electron Gas

Australian Journal of Physics, 1992

Approximate analytic expressions are derived for the linear response 4-tensor of a strongly magnestised, mildly relativistic electron plasma. The results are obtained within the framework of quantum plasma dynamics, thus the response contains relativistic and quantum effects that are essential in a super-strong magnetic field. The response is obtained in terms of relativistic plasma dispersion functions known as Shkarofsky functions. These functions allow the wave properties of the plasma to be studied without resorting to complicated numerical schemes. The response derived is valid for radiation with frequency up to about the cyclotron frequency and is of use in the theory of spectra formation in X-ray pulsars. In addition, a simple graphical technique is introduced that allows one to visually locate the roots of the resonant denominator occurring in the response, as well as determine the conditions under which both roots are valid and contribute to absorption.

Dispersion relations in ultradegenerate relativistic plasmas

Physical Review D, 2000

The propagation of excitation modes in a relativistic ultradegenerate plasma is modified by their interactions with the medium. These modifications can be computed by evaluating their on-shell self-energy, which gives (gaugeindependent) dispersion relations. For modes with momentum close to the Fermi momentum, the one-loop fermion self-energy is dominated by a diagram with a soft photon in the loop. We find the one-loop dispersion relations for quasiparticles and antiquasiparticles, which behave differently as a consequence of their very different phase-space restrictions when they scatter with the electrons of the Fermi sea. In a relativistic system, the unscreened magnetic interactions spoil the normal Fermi liquid behavior of the plasma. For small values of the Fermi velocity, we recover the non-relativistic dispersion relations of condensed matter systems.

On the relativistic plasma-dynamical and hydrodynamical normal modes

Physica A: Statistical Mechanics and its Applications, 1975

A plasma and a neutral fluid behave in very different ways in the so-called hydrodynamical limit, when submitted to a long-wavelength disturbance. Both cases can be treated however in the same way if the plasma-dynamical equations are properly regularized. The frequencies and damping rates of both relativistic neutral-fluid modes and relativistic plasma modes are discussed in detail. A new relativistic plasma effect is exhibited as an anomalous, wavelength-independent damping coefficient of longitudinal and transverse plasma oscillations. This effect originates from the contribution of the electric field to the heat flow in a relativistic plasma.

Introduction: Plasma Parameters and Simplest Models

Plasma Science [Working Title], 2020

Plasma is ionized gas (partially or fully). Overwhelming majority of matter in the universe is in plasma state (stars, Sun, etc.). Basic parameters of plasma state are given briefly as well as classification of plasma types: classic-quantum, idealnonideal, etc. Differences between plasma and neutral gas are presented. Plasma properties are determined by long distance electrostatic forces. If spatial dimensions of a system of charged particles exceed the so-called Debye radius, the system may be considered as plasma, that is, a medium with qualitatively new properties. The expressions for Debye radius for classical and quantum plasma are carried out. Basic principles of plasma description are presented. It is shown that plasma is a subject to specific electrostatic (or Langmuir) oscillations and instabilities. Simplest plasma models are given briefly: the model of "test" particle and model of two (electron and ion) fluids. As an example, Buneman instability is presented along with qualitative analysis of its complicate dispersion relation. Such analysis is typical in plasma theory. It allows to easily obtain the growth rate.