Magneto-modulational instability of a relativistic electron-positron plasma

It is shown that a magneto-modulational instability can develop in an electron-positron plasma. The main characteristics of this instability are presented in a fully relativistic treatment. The mechanism of the instability is associated with an anisotropy of the nonlinear plasma permittivity.     

Solitons in a relativistic plasma with negative ions

The interaction of the nonlinearity and the dispersiveness causing the solitary waves is studied in a relativistic plasma with negative ions through the derivation of a nonlinear partial-differential equation known as the Korteweg-de Vries equation. The negative ions play a salient part in the existence and behavior of the solitons and could be of interest in laboratory plasmas. First, the observations are made in a nonisothermal plasma, and later the reduction to the nonisothermality of the plasma shows entirely different characteristics as compared to the solitons in the isothermal plasmas. Comparison with the various solitons is emphasized     

Neutrino interaction with strongly magnetized electron-positron plasma

A study is made of a complete set of neutrino-electron processes in a magnetized plasma. It is shown that processes involving neutrinos in the initial and final states ve ^? → ve ^? and v ? ve ^? e ⁺ have kinematic amplification in the ultrarelativistic limit. Relatively simple expressions are obtained for the probability and average neutrino energy-momentum loss which are convenient for quantitative analysis. It is observed that the total contribution of ve processes did not depend on the chemical potential of the magnetized electron-positron plasma.     

Ion acoustic soliton propagation in a magnetized relativistic plasma

Summary The Korteweg-de Vries equation for ion acoustic waves in the presence of weakly relativistic ion streaming velocity is derived in a magnetic plasma. It is found that relativistic effects are important in the solitary wave propagation for both fast and slow modes. Earlier results are reconfirmed. To speed up publication, the authors of this paper have agreed to not receive the proofs for correction.     

Particle energization in an expanding magnetized relativistic plasma

Using a 21 / 2-dimensional particle-in-cell (PIC) code to simulate the relativistic expansion of a magnetized collisionless plasma into a vacuum, we report a new mechanism in which the magnetic energy is efficiently converted into the directed kinetic energy of a small fraction of surface particles. We study this mechanism for both electron-positron and electron-ion (m(i)/m(e)=100, m(e) is the electron rest mass) plasmas. For the electron-positron case, the pairs can be accelerated to ultrarelativistic energies. For electron-ion plasmas, most of the energy gain goes to the ions.     

Quasi-linear relativistic treatment of electron cyclotron fluctuations in a magnetized plasma

Summary The relativistic quasi-linear theory of electron cyclotron fluctuations is developed for a homogeneous plasma. Expressions are given for the absorption and emission coefficients, consistently with the currently employed linear theory. The extension to the inhomogeneousplasma case is considered and shown to allow the analysis of wave propagation, absorption and emission in plasmas of physical interest.

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Riassunto Si sviluppa la teoria quasi lineare relativistica per le fluttuazioni di onde elettroniche di ciclotrone per un plasma omogeneo. Si otteggono inoltre le espressioni dei coefficienti d'assorbimento ed emissione del plasma, consistentemente con la teoria lineare correntemente usata. Si considera infine l'estensione della teoria ad un plasma disomogeneo, applicandola all'analisi quantitativa di propagazione, assorbimento ed emissione di onde di ciclotrone.

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Резюме Для однородной плазмы развивается релятивистская квазилинейная теория электронных циклотронных флуктуаций. Приводятся вйражения для коэффициентов поглощения и испускания, соответствующих повсеместно используемой линейной теории. Рассматривается обобщения и излучения волн в плазме в физическн интересных случаях.

     

Statistical mechanics of a relativistic magnetized plasma and its radiation field

A relativistic BBGKY hierarchy for the system of a magnetized plasma plus radiation is developed in a manifestly covariant way. It is based on the Abraham-Lorentz-Dirac equation. Simple kinetic equations are obtained and briefly analysed.     

Bifurcation and Lorentz-factor scaling of relativistic magnetized plasma expansion

We report the long-term results of 2 1/2-dimensional particle-in-cell simulations of the relativistic expansion of strongly magnetized electron-positron plasmas. When the simulation is carried to >150 light-crossing time of the initial plasma, the plasma pulse exhibits a number of remarkable properties. These include the repeated bifurcation of the pulse profile, development of a power-law momentum distribution with low-energy cutoff, and a simple scaling law for the peak Lorentz factor.     

Solitons in relativistic laser-plasma interactions

Single or/and multipeak solitons in plasma under relativistic electromagnetic field are reviewed. The incident electromagnetic field is allowed to have a zero or/and nonzero initial constant amplitude. Some interesting numerical results are obtained that include a high-number multipeak laser pulse and single or/and low-number multipeak plasma wake structures. It is also shown that there exists a combination of soliton and oscillation waves for plasma wake field. Also, the electron density exhibits multi-caviton structure or the combination of caviton and oscillation. A complete eigenvalue spectrum of parameters is given wherein some higher peak numbers of multipeak electromagnetic solitons in the plasma are included. Moreover, some interesting scaling laws are presented for field energy via numerical approaches. Some implications of results are discussed.      

Electromagnetic wave scattering from a magnetized plasma column including a thin annular magnetized relativistic rotating electron beam (TAMRREB)

The problem of the scattering of electromagnetic waves from a magnetized plasma column including a thin annular magnetized relativistic rotating electron beam is discussed theoretically. The backscattering cross-section and scattering pattern are presented for a transverse electric (TE) polarization. An investigation on the effects of system parameters on the backscattering cross-section and scattering pattern is done and the corresponding polarized charge density plots are presented.     

Solitons in relativistic mean field models

Assuming that the nucleus can be treated as a perfect fluid we study the conditions for the formation and propagation of Korteweg–de Vries (KdV) solitons in nuclear matter. The KdV equation is obtained from the Euler and continuity equations in nonrelativistic hydrodynamics. The existence of these solitons depends on the nuclear equation of state, which, in our approach, comes from well-known relativistic mean field models. We reexamine early works on nuclear solitons, replacing the old equations of state by new ones, based on QHD and on its variants. Our analysis suggests that KdV solitons may indeed be formed in the nucleus with a width which, in some cases, can be smaller than one Fermi.     

Electrostatic solitary waves associated with relativistic nonextensive electrons in magnetized fusion plasma

Properties of nonlinear electrostatic solitary waves in a magnetized multicomponent system of plasma containing of warm fluid ions, weakly relativistic warm fluid electrons and q-nonextensive distributed electrons using reductive perturbation method, have been surveyed. For this purpose, a KdV soliton type solution has been employed. The dependence of solitary wave structure, solitary wave maximum amplitude, and phase velocity of soliton on the plasma parameters is defined numerically.     

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导出了无磁化无碰撞各向同性相对论正负电子对等离子体纵波的色散关系。使用逐次近似的标准技术,对两种极限情况下的纵波色散方程进行了解析研究。将完全色散方程进行变换,使它们完全适用于在需要完全相对论处理的温度范围内进行数值计算。用数值模拟方法得到了用解析方法不能得到的完全的色散曲线。     

Production of electron-positron pairs by a photon propagating in a strongly magnetized thermal bath

The production of electron-positron pairs by a photon propagating in a thermal bath in both zero and strong (B ≫ 4.41 × 10¹³ G) magnetic fields has been considered. The mean free path has been calculated for the high-energy photon propagating through a thermodynamically equilibrium photon gas along the magnetic field lines so that the γ → e ⁻ e ⁺ decay is kinematically forbidden. It has been shown that the strong magnetic field suppresses the probability of the γγ′ → e ⁻ e ⁺ process. The analyzed process can be useful for analysis of possible mechanisms of the generation of the e ⁻ e ⁺ plasma in the regions of the polar caps of magnetars.     

Ultrarelativistic electron-positron plasma

Ultrarelativistic electron-positron plasmas can be produced in high-intensity laser fields and play a role in various astrophysical situations. Their properties can be calculated using QED at finite temperature. Here we will use perturbative QED at finite temperature for calculating various important properties, such as the equation of state, dispersion relations of collective plasma modes of photons and electrons, Debye screening, damping rates, mean free paths, collision times, transport coefficients, and particle production rates, of ultrarelativistic electron-positron plasmas. In particular, we will focus on electron-positron plasmas produced with ultra-strong lasers.     

Ballooning vortex in a magnetized plasma

The existence of a ballooning solitary vortex in an inhomogeneous plasma immersed in crossed magnetic and gravitational fields is demonstrated.