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1.
In the presence of an applied uniform magnetic field Bo, the properties of 2-dimensional (2D) magnetosonic solitary waves of relativistic amplitude in the plasma containing electron, light ions He^+, and heavy ions O+ are presented. In the weakly relativistic limit, a Kadomtsev Petviashvili (KP) equation is derived by reductive perturbation method. We give the N-soliton solution of the KP equation and find dromion solutions of a potential of the physical field. The interaction law of the dromions is obtained, which shows there is no exchange of energy, momentum, and angular momentum before and after interaction of the dromions except for phase shifts.  相似文献   

2.
Solitary waves in relativistic electromagnetic plasmas are obtained numerically. The longitudinal momentum of electrons has been taken into account in the problem. It is found that in the moving frame with electromagnetic field propagating the solitary waves can exist in both cases, where the vector potential frequency is larger or smaller than the plasma characteristic frequency.  相似文献   

3.
Recently, laser and microwave scatterings have become one of the important diagnostic means for plasma. Laser and microwave correlative scattering spectrum is determined by particle-density fluctuations in a weak turbulent plasma. In a relativistic plasma, on the basis of complete electromagnetic interaction between particles, a general expression for particle density fluctuations and spectra of laser and microwave scattering from a magnetized plasma are derived. The laser and microwave scattering spectra provide information on electron density and temperature, ion temperature, resonance and nonresonance effects.  相似文献   

4.
Finite-Difference Time-Domain (FDTD) algorithms are applied to study the transformation of a pre-existing electromagnetic plane wave by prescribed time variation of a cold magnetoplasma with a magnetic field along the propagation direction. A one-dimensional FDTD code is used to verify the results obtained earlier using analytical approximations based on (a) WKB method for slow switching of the plasma medium and (b) Green's function technique for rapid switching of the plasma medium. A novel successive reduction method has been developed and applied to obtain the amplitudes and the frequencies of the new modes generated by the switching of the medium.  相似文献   

5.
Two-dimensional (2D) relativistic magnetosonic solitons in the negative-ion-rich plasma consisting of positive ions Ar+, negative ions SF6- and electrons are investigated in the presence of an applied magnetic field B0 and can be described by a Kadomtsev--Petviashvili (KP) equation in the weakly relativistic limit. The ratio of positive ion density to negative ion density has a marked influence on the amplitude Φm and width W of the steady-state KP soliton. The interaction law of the nontrivial solitons with rich web structure is studied by the Wronskian determinant method.  相似文献   

6.
丁荣源  陆全康 《光学学报》1996,16(4):12-415
激光在完全电解等离子体中集体散射截面等于单个电子的汤姆逊散射截面乘以结构因子,结构因子由电子密度涨落确定。在考虑电粒子间电磁相同作用基础上,给出激光在相对论磁化等离子体中散射的结构因子谱的解析表示式。  相似文献   

7.
The properties of waves propagating in amagnetized dusty plasma are analyzed for both high andlow values of the ion-cyclotron frequency. The electronsare considered to be hot. The dispersion relation for a wave propagating through the dusty plasmaat an arbitrary angle with the external magnetic fieldis derived. This rectifies some errors in the earliertreatment of Cramer and Vladimirov (1996). Effects of the presence of the dust on thecharacteristics of wave propagation arediscussed.  相似文献   

8.
The nonlinear propagation of cylindrical and spherical modified ion-acoustic (mIA) waves in an unmagnetized, collisionless, relativistic, degenerate multispecies plasma has been investigated theoretically. This plasma system is assumed to contain both relativistic degenerate electron and positron fluids, nonrelativistic degenerate positive and negative ions, and positively charged static heavy ions. The restoring force is provided by the degenerate pressures of the electrons and positrons, whereas the inertia is provided by the mass of positive and negative ions. The positively charged static heavy ions participate only in maintaining the quasi-neutrality condition at equilibrium. The nonplanar K-dV and mK-dV equations are derived by using reductive perturbation technique and numerically analyzed to identify the basic features (speed, amplitude, width, etc.) of mIA solitary structures. The basic characteristics of mIA solitary waves are found to be significantly modified by the effects of degenerate pressures of electron, positron, and ion fluids, their number densities, and various charge states of heavy ions. The implications of our results to dense plasmas in astrophysical compact objects (e.g., nonrotating white dwarfs, neutron stars, etc.) are briefly mentioned.  相似文献   

9.
Usually, only Coulomb interactions between charged particles which are independent of time are considered in BBGKY theory of a nonrelativistic plasma. In relativistic case, the induced electromagnetic forces between charged particles which are dependent on time obviously should be considered. A Lorentz-covariant generalized n-time Liouville equation for classical plasma is established. A convenient form applicable to the laboratory frame of this equation is also given. The relativistic BBGKY hierarchy is developed in which both Coulomb and electromagnetic forces between particles are included. A method for solving the relativistic pair correlation equation is given in polarization approximation. A new formula for calculating collision integral in terms of discrete particle Green functions is given. A number of generalized Boltzmann equations for relativistic plasmas are derived.  相似文献   

10.
By employing the reductive perturbation technique, the propagation of cylindrical and spherical ion acoustic solitary waves is studied in an unmagnetized dense relativistic plasma, consisting of relativistically degenerate electrons and cold fluid ions. A modified Korteweg-de-Vries equation is derived and its numerical solutions have been analyzed to identify the basic features of electrostatic solitary structures that may form in such a degenerate Fermi plasma. Different degrees of relativistic electron degeneracy are discussed and compared. It is found that increasing number density leads to decrease the amplitude the width of the ion acoustic solitary wave in both the cylindrical and spherical geometries. The relevance of the work to the compact astrophysical objects, particularly white dwarfs is pointed out.  相似文献   

11.
Absorbers and reflectors of electromagnetic waves have many applications, and so the interactions between electromagnetic waves and low-temperature plasma, particularly numerical analysis of reflection, absorption, and transmission of electromagnetic waves in unmagnetized, magnetized, nonuniform, and uniform plasma, have been a topic of intensive research. For instance, Laroussi numerically evaluated the interactions between electromagnetic waves and a uniform magnetized plasma cylinder, and Helaly and Yeh studied the scattering from nonuniform magnetized plasma cylinders.  相似文献   

12.
In this work, an adaptation of the tanh/tan-method that is discussed usually in the nonlinear partial differential equations is presented to solve nonlinear polynomial differential-difference equations. As a concrete example, several solitary wave and periodic wave solutions for the chain which is related to the relativistic Toda lattice are derived. Some systems of the differential-difference equations that can be solved using our approach are listed and a discussion is given in conclusion.  相似文献   

13.
The resonant interaction between three waves propagating perpendicularly to an external magnetic field in a plasma is considered. We present the explicit expressions for the three wave coupling coefficients of a warm multi‐component plasma. The results of previous work on the generation of THz radiation by laser plasma interaction are significantly improved. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

14.
A rigorous theoretical investigation has been made to study the existence and basic features of the ion-acoustic (IA) shock structures in an unmagnetized, collisionless multi-ion plasma system (containing degenerate electron fluids, inertial positively as well as negatively charged ions, and arbitrarily charged static heavy ions). This investigation is valid for both non-relativistic and ultra-relativistic limits. The reductive perturbation technique has been employed to derive the modified Burgers equation. The solution of this equation has been numerically examined to study the basic properties of shock structures. The basic features (speed, amplitude, width, etc.) of these electrostatic shock structures have been briefly discussed. The basic properties of the IA shock waves are found to be significantly modified by the effects of arbitrarily charged static heavy ions and the plasma particle number densities. The implications of our results in space and interstellar compact objects like white dwarfs, neutron stars, black holes, and so on have been briefly discussed.  相似文献   

15.
The relativistic two-body problem is considered for spinless particles subject to an external electromagnetic field. When this field is made of the monochromatic superposition of two counter-propagating plane waves (and provided the mutual interaction between particles is known), it is possible to write down explicitly a pair of coupled wave equations (corresponding to a pair of mass-shell constraints) which takes into account also the field contribution. These equations are manifestly covariant; constants of the motion are exhibited, so one ends up with a reduced problem involving five degrees of freedom.  相似文献   

16.
To describe the long time asymptotic behaviour of weakly nonlinear plasma waves propagating in a strongly magnetized plasmafilled cylindrical waveguide the usual KDV equation which is first order in wave amplitude is extended to second order including the effects of finite temperature, mobile ions and giving a proper treatment to the radial co-ordinate for all possible modes of propagation. The second-order effects on the first-order solitary wave profile, phase speed and first order correction to the wavelength are all determined and discussed.  相似文献   

17.
利用积分因子法对非均匀圆柱壳中传播孤立波的动力学稳定性进行详细的数值研究.以高斯波扰动、简谐波扰动和随机扰动作为初始扰动,考察受到这三种不同扰动的孤立波能否较长时间保持波形结构和传播速度而稳定传播的问题.结果表明:孤立波的稳定传播与扰动幅度、宽度和波长有关,只在受到幅度、宽度和波长都足够小的扰动下非均匀圆柱壳中传播的孤立波才能够表现出较强的抗干扰性,具有良好的动力学稳定性.  相似文献   

18.
A three-dimensional(3D)BurgersJ equation adopting perturbative methodology is derived to study the evolution of a shock wave with Landau quantized magnetic field in relativistic quantum plasma.The characteristics of a shock wave in such a plasma under the influence of magnetic quantization,relativistic parameter and degenerate electron density are studied with assistance of steady state solution.The magnetic field has a noteworthy control,especially on the shock wave's amplitude in the lower range of the electron density,whereas the amplitude in the higher range of the electron density reduces remarkably.The rate of increase of shock wave potential is much higher(lower)with a magnetic Held in the lower(higher)range of electron density.With the relativistic factor,the shock wave's amplitude increases significantly and the rate of increase is higher(lower)for lower(higher)electron density.The combined effect of the increase of relativistic factor and the magnetic field on the strength of the shock wave,results in the highest value of the wave potential in the lower range of the degenerate electron density.  相似文献   

19.
By using the relativistic quantum magnetohydrodynamic model, the extraordinary electromagnetic waves in magnetized quantum plasmas are investigated with the effects of particle dispersion associated with the quantum Bohm potential effects, the electron spin-1/2 effects, and the relativistic degenerate pressure effects. The electrons are treated as a quantum and magnetized species, while the ions are classical ones. The new general dispersion relations are derived and analyzed in some interesting special cases. Quantum effects are shown to affect the dispersion relations of the extraordinary electromagnetic waves. It is also shown that the relativistic degenerate pressure effects significantly modify the dispersive properties of the extraordinary electromagnetic waves. The present investigation should be useful for understanding the collective interactions in dense astrophysical bodies,such as the atmosphere of neutron stars and the interior of massive white dwarfs.  相似文献   

20.
The electromagnetic propagation through a magnetized plasma slab is studied using the finite-difference time-domain method by means of the z transform The reflection and transmission coefficients of the magnetoactive plasma for the right-hand circularly polarized wave are presented. The comparison of the results of the Z transform and recursive convolution algorithms with analytic values indicates that the Z transform algorithm is more accurate than the recursive convolution algorithm. The Z transform algorithm overcomes the drawback that the recursive algorithm cannot predict the transmission coefficient of the magnetized plasma slab for the right-hand circularly polarized wave in the stop band.  相似文献   

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