Quantum Zakharov-Kuznetsov equation for pair ion plasma in the presence of quantized magnetic field

We derive Quantum Zakharov-Kuznetsov to study ion acoustic solitons propagating in electron positron (hole) ion degenerate plasma with quantized magnetic field and exchange corelation effects

Lattice modes in a dusty plasma crystal

A model is presented to explain the normal mode features of dust particles in a planar zigzag crystal chain for the first and second neighbors. The degrees of freedom of particles are the longitudinal and transverse displacements in plane coupled by the first and second neighbor harmonic forces in two-dimensions (2D). The constant electric force duded to the electrodes to keep the zigzag structure is calculated. The coupling between transverse and longitudinal dust-lattice (DL) modes is derived. The latter is considered due to the energy of the electrostatic (Yukawa) potential. Moreover coupled (acoustic and optical) and decoupled (longitudinal and transverse) branches of dust lattice modes for different lattice parameters and structures are studied. Propagation of the longitudinal and acoustic modes is found to be strictly dependent on the value of the distance between the two chains; below that value mode may not propagate Finally it is shown that the frequencies of the acoustic (optical) branches increase (decrease) with increasing the distance between the two chains

Weibel instability in relativistic asymmetric electron positron plasma

We consider a situation in when the interaction of relativistically intense EM waves with an isotropic electron positron plasma takes place, i.e.,we consider short pulse lasers with intensity up to 1021 W/cm2, in which the photon density is of the order of 1030cm3 and the strength of electric field E = 10^9 statvolt/cm. Such a situation is possible in astrophysical and laboratory plasma which are subject to intense laser radiation, thus leading to non thermal equilibrium field radiations. Such interaction of the super-strong laser radiation with an isotropic pair plasma leads to the generation of low frequency electromagnetic EM waves and in particular a quasistationary magnetic field. When the relativistic circularly polarized transverse EM wave propagates along z- axis, it creates a ponderomotive force, which affects the motion of particles along the direction of its propagation. On the other hand, motion of the particles across the direction of propagation is defined by the ponderomotive potential. Moreover dispersion relation for the transverse EM wave using a special distribution function, which has an anisotropic form, is derived and is subsequently investigated for a number of special cases. In general, it is shown that the growth rate of the EM wave strongly depends upon its intensity

A modified orbital motion limited (OML) theory

The validity of the orbital motion limited (OML) theory is reviewed with reference to the floating potential acquired by a spherical object immersed in a plasma. A new and perhaps more realistic approach for obtaining the floating potential is introduced by including the current outward from the spherical object and the current coming from infinity. This novel approach is also valid for cases where the standard OML theory ceases to apply.Comment: 4 pages, 2 figure

Modulation instability of lower hybrid waves leading to cusp solitons in electron-positron-ion Thomas Fermi plasma

Following the idea of three wave resonant interactions of lower hybrid waves it is shown that quantum -modified lower hybrid (QLH) wave in electron positron ion plasma with spatial dispersion can decay into another QLH wave ( where electron and positrons are activated whereas ions remain in the background) and another ultra low frequency QULH (where ions are mobile). Quantum effects like Bohm potential, exchange correlation and Fermi pressure on the lower hybrid wave significantly reshaped the dispersion properties of lower hybrid waves. Later a set of nonlinear Zakharov equations have been derived to consider the formation of QLH wave solitons with the nonlinear contribution coming from the QLH waves. Further, modulational instability of the lower hybrid wave solitons is investigated and consequently it's growth rates are examined for different limiting cases. Since the growth rate associated with the three-wave resonant interaction are generally smaller than the growth associated with the modulational instability, therefore only latter have been investigated. Soliton solutions from the set of coupled Zakharov and NLS equations in the quasi-stationary regime have been studied. Ordinary solitons are attribute of nonlinearity whereas a cusp soliton solution featured by nonlocal nonlinearity have also studied. Such an approach to lower hybrid waves and cusp solitons study in Fermi gas comprising electron positron and ions is new and important. The general results obtained in this quantum plasma theory will have widespread applicability, particularly for processes in high energy plasma-laser interactions set for laboratory astrophysics and solid state plasmas.Comment: 16 page

Gravitational Instability Analysis in Multi-Ion Dense Quantum Magnetoplasma

Electrostatic Gravitational or Rayleigh-Taylor (RT) instability in an inhomogeneous magnetized multi-ions plasma with some fraction of quantum mechanical electrons. The effect of Bohm potential, temperature degeneracy and magnetic field are carried out. A generalized dispersion relation is deduced under the drift approximation. The presence of negative ions with their different streaming velocities make the dispersion relation a cubic equation. Different roots of both real and imaginary parts of the RT mode are studied by using the Cardano method of solving the cubic equation. The growth rates of RT instability are examined analytically and numerically. It is shown that the basic features of these waves are significantly modified by the positive and negative ions drift speed as well as by the magnetic field and density. Relevance of the work regarding to dense astrophysical plasmas is pointed out.Comment: We submitted this article to a couple of journals but it got rejected. Because this model is fundamentally wrong. So we request for the withdrawal of this articl

Bernstein Waves in Symmetric and Asymmetric Pair Ions Plasma

Positive and negative ions forming so-called pair plasma differing in sign of their charge and asymmetric in mass and temperature support a new electrostatic mode. Bernstein mode for a pair ions and pair ions with contribution of electrons in pair plasma both cases are investigated. By solving the linearized Vlasov equation along Maxwell equations, a generalized expression for the Bernstein waves is derived by employing the Maxwell distribution function. In paper we discuss the different types of ions Bernstein waves and comparison of the symmetry and asymmetry on these ions Bernstein waves. We also apply the fluid limit on these Bernstein waves and we different fluid results from kinetic theory.Comment: 10 page

Effects of quantum statistical pressure and exchange correlation on the low frequency electromagnetic waves in degenerate Fermi-Dirac pair-ion plasma

The low frequency, long wavelength electromagnetic waves, viz, shear Alfven wave in quantum electron-positron-ion magneto plasmas, have been examined using quantum magneto hydrodynamic model. In this model, we have considered electrons and positrons are to be magnetized as well as degenerate whereas ions are magnetized but classical. We have also included the effects of exchange correlation terms which appear entirely the dynamic equations of electrons and positrons. The whole treatment is done using multi-fluid model. Our object is to study the shear Alfv\'en waves propagating in above said system of plasma. For that we have derived the modified dispersion relation of the shear Alfv\'en waves. Results are relevant to the terrestrial laboratory astrophysics.Comment: 13 pages, 4 figure

Shocklets in the Comet Halley Plasma

Dust acoustic (DA) waves evolving into shocklets are investigated in the Comet Halley plasma system relaxing to Maxwellian, Kappa and Cairns distributions. Here dynamics of dust is described by the fully nonlinear continuity and momentum equations. A set of two characteristic wave nonlinear equations is obtained and numerically solved to examine the DA solitary pulse which develops into oscillatory shocklets with the course of time such as at time {\tau}=0, symmetric solitary pulses are formed, which develop into oscillatory shocklets. It has been observed that variation in superthermality strongly affects the profiles of nonlinear DA structures in terms of negative potential, dust velocity and density

Acceleration of dust particles by vortex ring

It is shown that nonlinear interaction between large amplitude circularly polarized EM wave and dusty plasma leads to a nonstationary ponderomotive force which in turn produces a vortex ring, and magnetic field. Then the ensuing vortex ring in the direction of propagation of the pump wave can accelerate the micron-size dust particles which are initially at rest and eventually form a non relativistic dust jet. This effect is purely nonstationary and unlike linear vortices, dust particles do not rotate here. Specifically, it is pointed out that the vortex ring or closed filament can become potential candidate for the acceleration of dust in tokamak plasmas