Generation of wakefields and electromagnetic solitons in relativistic degenerate plasmas (original) (raw)
Related papers
Nondrifting relativistic electromagnetic solitons in plasmas
Laser and Particle Beams, 2003
Low-frequency, relativistic, subcycle solitary waves are found in two-dimensional and three-dimensional particle-in-cell~PIC! numerical simulations, as a result of the interaction of ultrashort, high-intensity laser pulses with plasmas. Moreover, nondrifting, subcycle relativistic electromagnetic solitons have been obtained as solutions of the hydrodynamic equations for an electron-ion warm plasma, by assuming the quasi-neutrality character of the plasma response. In addition, the formation of long-living macroscopic soliton-like structures has been experimentally observed by means of the proton imaging diagnostics. Several common features result from these investigations, as, for example, the quasi-neutral plasma response to the soliton radiation, in the long-term evolution of the system, which leads to the almost complete expulsion of the plasma from the region where the electromagnetic radiation is concentrated, even at subrelativistic field intensity. The results of the theoretical investigations are reviewed with special attention to these similarities.
Electromagnetic solitons in degenerate relativistic electron–positron plasma
Physica Scripta, 2015
The existence of soliton-like electromagnetic (EM) distributions in a fully degenerate electronpositron plasma is studied applying relativistic hydrodynamic and Maxwell equations. For circularly polarized wave it is found that the soliton solutions exist both in relativistic as well as nonrelativistic degenerate plasmas. Plasma density in the region of soliton pulse localization is reduced considerably. The possibility of plasma cavitation is also shown.
Journal of Experimental and Theoretical Physics Letters, 2004
The nonlinear interaction between the electron-positron pairs produced by an electromagnetic wave in plasma and the wave leads to damping of the wave, frequency upshift, change of polarization, and particle acceleration. The case of a circularly polarized wave is investigated in the framework of the relativistic Vlasov equation with a source term based on the Schwinger formula for the pair creation rate.
Contributions to Plasma Physics, 2019
The oblique propagation of the quantum electrostatic solitary waves in magnetized relativistic quantum plasma is investigated using the quantum hydrodynamic equations. The plasma consists of dynamic relativistic degenerate electrons and positrons and a weakly relativistic ion beam. The Zakharov-Kuznetsov equation is derived using the standard reductive perturbation technique that admits an obliquely propagating soliton solution. It is found that two types of quantum acoustic modes, that is, a slow acoustic mode and fast acoustic mode, could be propagated in our plasma model. The parameter that determines the nature of soliton, that is, compressive or rarefactive soliton, for slow mode is investigated. Our numerical results show that for the slow mode, the determining parameter is ion beam velocity in the case of relativistic degenerate electrons. We also have examined the effects of plasma parameters (like the beam velocity, the density ratio of positron to electron, the relativistic factor, and the propagation angle) on the characteristics of solitary waves.
Weakly relativistic solitons in a magnetized ion-beam plasma in presence of electron inertia
Physics of Plasmas, 2011
The relativistic compressive solitons of fast ion-acoustic mode are established in this magnetized plasma for the introduction of relativistic beam when QЈ͑=m b / m i ͒ Ͼ 1 or Ͻ1 subject to v s0 − v b0 = U d sin ͑v s0 = ion initial streaming, v b0 = beam initial streaming, and U d is the beam drift perpendicular to the direction of magnetic field͒. The lighter concentration of beam ions ͑QЈ Ͻ 1͒ in the plasma admits slower variation in amplitudes after some critical N b ͑=beam density͒ for all ͑cos ͒. Further, it is shown that under smaller relativistic effect ͑v b0 / c = 0.10 and v s0 / c = 0.10͒ for small concentration of beam ions ͑QЈ Ͻ 1͒ in the plasma, the growth of soliton amplitude becomes smaller with the increase of N b . But to the contrary, for heavier concentration of beam ions QЈ͑Ͼ1͒, the amplitudes of solitons decay considerably with QЈ growing sharply to a maximum in the vicinity of QЈ Ϸ 1.
Astrophysics and Space Science, 1980
The modulational instability of the weakly nonlinear longitudinal Langmuir as well as the transverse electromagnetic waves, propagation in the relativistic plasma without the static fields is described. The nonlinear Schr6dinger equation taking account of the nonlinear Landau damping for these waves has been derived by means of the relativistic Vlasov and Maxwell equations. The plasma with the weakly relativistic temperature and that with an ultrarelativistic one has been investigated. In the first case, for the electron-proton plasma with the temperature more than 2.3 KeV we found the regional change of the wave numbers for which the soliton of two types, subsonic and supersonic, can exist. The soliton of the transverse waves can exist when the group velocity of the waves is between the thermal velocity of the electron and ion and the length of the linear waves is less than 27rc/o~p~. In the second case the regions of the wave numbers, with the solitons of the Langmuir and transverse waves have been determined. The nonlinear waves in the electron-positron plasma and the waves with the phase velocity, which is about the light one, are also considered in the following paper.
Chaos, Solitons & Fractals, 2009
In some recent on board space observations, it has been studied that high streaming ions play a major role on the physical mechanism for nonlinear wave structures. We have investigated here ion-acoustic solitons in a plasma with nonthermal electrons and weakly relativistic ions. Such plasmas occur in plasma sheet boundary layer of earth's magnetosphere, Van-Allen belts. We have set up and solved KdV equation in a stationary frame to obtain the expression for the peak soliton amplitude and width. These quantities are significantly influenced by the relativistic effect, the nonthermal parameters and ratio of ion to electron temperatures. It is observed that for specific range of nonthermal parameter values, we observe compressive solitons and above which the rarefactive solitons are observed. The nonthermal parameter also affects the double layers.
Physics of Plasmas, 2006
A numerical fluid simulation investigation of the temporal evolution of a special class of traveling wave solutions of the one dimensional relativistic cold plasma model is reported. The solutions consist of coupled electromagnetic and plasma waves in a solitary pulse shape (Phys. Rev. Lett. 68, 3172 (1992); Phys. Plasmas 9, 1820 (2002)). Issues pertaining to their stability, mutual collisional interactions and propagation in an inhomogeneous plasma medium are addressed. It is found that solitary pulses that consist of a single light peak trapped in a modulated density structure are long lived whereas structures with multiple peaks of trapped light develop an instability at the trailing edge. The interaction properties of two single peak structures show interesting dependencies on their relative amplitudes and propagation speeds and can be understood in terms of their propagation characteristics in an inhomogeneous plasma medium.
Physics of Plasmas, 2016
A system of nonlinear one-dimensional equations of the electron hydrodynamics with Maxwell's equations was developed to describe electromagnetic (EM) solitons in plasma with nonthermal electrons. Equation of vector potential was derived in relativistic regime by implementing the multiple scales technique, and their solitonic answers were introduced. The allowed regions for bright and dark electromagnetic solitons were discussed in detail. Roles of number density of nonthermal electrons, temperature of electrons, and frequency of fast participate of vector potential on the Sagdeev potential and properties of EM soliton were investigated. Results show that with increasing the number of nonthermal electrons, the amplitude of vector potential of bright solitons increases. By increasing the number of nonthermal electrons, dark EM solitons may be changed to bright solitons. Increasing the energy of nonthermal electrons leads to generation of high amplitude solitons. Published by AIP Publishing.