It is pointed out that electrostatic and electromagnetic waves propagating in perpendicular direction to the density gradient $\nabla n_0=\hat{x} |\frac{dn_0}{dx}|$ and external magnetic field $\vec{B}_0=B_0 \hat{z}$ in hybrid frequency... more
It is pointed out that electrostatic and electromagnetic waves propagating in perpendicular direction to the density gradient $\nabla n_0=\hat{x} |\frac{dn_0}{dx}|$ and external magnetic field $\vec{B}_0=B_0 \hat{z}$ in hybrid frequency range $\Omega_i \ll \omega \ll \Omega_e$ (where $\Omega_j=\frac{eB_0}{m_j c}$ and $j=e,i$) have several applications in space and laboratory plasmas. The electron plasma waves are important for the future experiments on heavier ion plasmas as well as the results are applicable to the experiments performed to create pure pair ion fullerene plasmas. The electrostatic modes are shown to exist in upper F-region of terrestrial ionosphere and electromagnetic waves are applied to cylindrically bounded heavy ion plasmas.
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A theoretical model for the generation of 'seed' magnetic field and plasma flow on galactic scales driven by externally given baro-clinic vectors is presented. The incompressible plasma fields can grow from zero values at... more
A theoretical model for the generation of 'seed' magnetic field and plasma flow on galactic scales driven by externally given baro-clinic vectors is presented. The incompressible plasma fields can grow from zero values at initial time t = 0 from a non-equilibrium state Te != Ti (where Te(Ti) are electron(ion) temperatures, respectively) due to pressure gradients. An exact analytical solution of the set of two fluid equations is obtained which is valid for both small and large plasma beta-values. The magnetic field generated by this mechanism has three dimensional structure. Weaknesses of previous single fluid models for seed magnetic field generation are also pointed out. The estimate of the magnitude of the galactic seed magnetic field turns out to be 10-15 G and may vary depending upon the scale lengths of the density and temperature gradients. The seed magnetic field may be amplified later by alphaomega-dynamo (or by some other mechanism) to the present observed values of ~ (2 - 10)muG. The theory has been applied to laser-induced plasmas as well and the estimate of the magnetic field's magnitude is in agreement with the experimentally observed values.
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Abstract We present nonlinear properties of the low-frequency nonlinear electrostatic waves in a nonuniform bounded magneto-plasma with the equilibrium density and parallel ion velocity gradients along the radial direction. The existence... more
Abstract We present nonlinear properties of the low-frequency nonlinear electrostatic waves in a nonuniform bounded magneto-plasma with the equilibrium density and parallel ion velocity gradients along the radial direction. The existence of electrostatic global vortices in a cylindrical magnetoplasma is established. The present results should help to understand the properties of coherent vortical structures in the presence of a magnetic field-aligned ion flow with a radial ion velocity gradient in laboratory magnetoplasmas that are bounded and nonuniform.
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... OAPokhotelov, OGOnishchenko, PKShukla, and L.Stenflo, Drift-Alfv[e-acute]n vortices in dusty plasmas, J. Geophys. Res., [Atmos.] 104, 19797 (1999). Q.Haque and H.Saleem, J. Geophys. Res., [Atmos.] 108, 1433 (2003). W.Horton and... more
... OAPokhotelov, OGOnishchenko, PKShukla, and L.Stenflo, Drift-Alfv[e-acute]n vortices in dusty plasmas, J. Geophys. Res., [Atmos.] 104, 19797 (1999). Q.Haque and H.Saleem, J. Geophys. Res., [Atmos.] 108, 1433 (2003). W.Horton and J.Liu, Drift waves in rotating plasmas ...
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Linear and nonlinear inertial Alfvén waves are studied in the presence of positively and negatively charged dust in electron-ion plasmas. The Sagdeev potential approach is employed to obtain solitary inertial Alfvén waves in such a... more
Linear and nonlinear inertial Alfvén waves are studied in the presence of positively and negatively charged dust in electron-ion plasmas. The Sagdeev potential approach is employed to obtain solitary inertial Alfvén waves in such a multicomponent plasma. It is found that electron density dips are formed in the super Alfvénic region, which has behavior similar to the case of electron-ion
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A shear flow instability in a nonuniform partially ionized magnetoplasma has been investigated and the angular momentum transport of charged particles caused by drift waves has been estimated. The angular momentum transport of the... more
A shear flow instability in a nonuniform partially ionized magnetoplasma has been investigated and the angular momentum transport of charged particles caused by drift waves has been estimated. The angular momentum transport of the electrons and ions is not equal because the system is not conservative. The present investigation should help to understand the origin of fluctuations and associated parallel
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ABSTRACT It is pointed out that the local drift wave instabilities can be suppressed by injecting positrons in the usual electron–ion plasmas. It has been found also that the global mode frequency in a bounded cylindrical plasma can be... more
ABSTRACT It is pointed out that the local drift wave instabilities can be suppressed by injecting positrons in the usual electron–ion plasmas. It has been found also that the global mode frequency in a bounded cylindrical plasma can be extremely reduced if the positron concentration is increased. The amplitude of the mode is not dependent upon the eigen-frequency. The local drift wave behavior in a sheared magnetic field has also been presented using Cartesian geometry. This investigation can be useful for future laboratory experiments.
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The Korteweg-de Vries electrostatic solitons are studied in the presence of anisotropic ion pressure in a strongly magnetized plasma. The anisotropic ion pressure is defined using double adiabatic Chew-Golberger-Low (CGL) theory. It is... more
The Korteweg-de Vries electrostatic solitons are studied in the presence of anisotropic ion pressure in a strongly magnetized plasma. The anisotropic ion pressure is defined using double adiabatic Chew-Golberger-Low (CGL) theory. It is found that for the case when perpendicular ion pressure is greater than the parallel pressure, the increase in perpendicular pressure increases the width of the structure, while
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Pair-ion plasma in the presence of dust particles and electrons has been studied. A coupled linear dispersion relation containing dust ion acoustic, dust acoustic and drift waves has been found. Many standard dispersion relations have... more
Pair-ion plasma in the presence of dust particles and electrons has been studied. A coupled linear dispersion relation containing dust ion acoustic, dust acoustic and drift waves has been found. Many standard dispersion relations have been discussed in different limits. In the nonlinear regime, the stationary solution in the form of dipolar vortices has been obtained. It is noticed that
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Nonlinear set of equations for inertial or slow shear Alfvén wave (SSAW) in ideal electron-positron-ion (epi) plasmas are presented. The analytical solution for arbitrary amplitude SSAW in such multi-component plasmas is obtained using... more
Nonlinear set of equations for inertial or slow shear Alfvén wave (SSAW) in ideal electron-positron-ion (epi) plasmas are presented. The analytical solution for arbitrary amplitude SSAW in such multi-component plasmas is obtained using Sagdeev potential approach. ...
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We investigate the effects of a slowly rotating compact gravitational source on electron oscillations in a homogeneous electrically neutral plasma in the absence of an external electric or magnetic field. Neglecting the random thermal... more
We investigate the effects of a slowly rotating compact gravitational source on electron oscillations in a homogeneous electrically neutral plasma in the absence of an external electric or magnetic field. Neglecting the random thermal motion of the electrons we assume the ...