Zakia Rahim - Academia.edu (original) (raw)
Uploads
Papers by Zakia Rahim
Physical Review E, 2019
The quantum hydrodynamic model is used to study the linear and nonlinear properties of small ampl... more The quantum hydrodynamic model is used to study the linear and nonlinear properties of small amplitude magnetosonic shock waves in dissipative plasma with degenerate inertialess spin-up and spin-down electrons and inertial classical ions. Spin effects are considered via spin pressure and macroscopic spin magnetization current. A linear dispersion relation is derived analytically and plotted numerically for different plasma parameters such as spin density, polarization ratio, plasma beta, quantum diffraction, spin magnetization energy, and magnetic diffusivity. Employing the standard reductive perturbation technique, a Korteweg-de Vries-Burgerstype equation is derived for small amplitude waves and studied numerically. We have observed that an oscillatory and monotonic shock waves are generated depending upon the plasma configurations. The phase portraits of both oscillatory and monotonic shock waves are also presented. Interestingly, different plasma parameters are found to play a significant role in the transition of oscillatory to monotonic shock waves or vice versa. Most importantly it is found that, the magnetosonic excitations obtained with spin-up and spin-down electrons are significantly different from the usual electron ion quantum plasma. The work presented is related to magnetosonic waves in dense astrophysical environments such as a pulsar magnetosphere and neutron stars.
Journal of the Physical Society of Japan, 2020
We investigate the wave propagation characteristics and head-on collision of low-frequency magnet... more We investigate the wave propagation characteristics and head-on collision of low-frequency magnetosonic waves in a dissipative plasma consisting of classical ions and degenerate inertia-less spin-up and spin-down electrons. Spin features are modeled via the macroscopic spin magnetization current and spin pressure. Employing the extended Poincare-Lighthill-Kuo perturbation method, a couple of Korteweg-de Vries-Burgers (KdVB) type equations are derived for small amplitude counter traveling magnetosonic waves. We traced out the parametric regime of compressive and rarefactive magnetosonic waves based on our plasma configurations. The phase shift effects of magnetosonic shock waves post-collision are also shown. We observe that the colliding process and phase shifts are significantly affected by various system configurational parameters, such as spin polarization, quantum diffraction, spin magnetization energy, and magnetic diffusivity. Importantly, we noticed that the head-on collision of two counter traveling magnetosonic shocks waves bearing spin polarization effect is significantly different from the usual electron-ion quantum plasma case. The work presented is related to the study of collective phenomena related to magnetosonic wave interaction, which is of great importance in dense astrophysical environments.
Physical Review E, 2019
The quantum hydrodynamic model is used to study the linear and nonlinear properties of small ampl... more The quantum hydrodynamic model is used to study the linear and nonlinear properties of small amplitude magnetosonic shock waves in dissipative plasma with degenerate inertialess spin-up and spin-down electrons and inertial classical ions. Spin effects are considered via spin pressure and macroscopic spin magnetization current. A linear dispersion relation is derived analytically and plotted numerically for different plasma parameters such as spin density, polarization ratio, plasma beta, quantum diffraction, spin magnetization energy, and magnetic diffusivity. Employing the standard reductive perturbation technique, a Korteweg-de Vries-Burgerstype equation is derived for small amplitude waves and studied numerically. We have observed that an oscillatory and monotonic shock waves are generated depending upon the plasma configurations. The phase portraits of both oscillatory and monotonic shock waves are also presented. Interestingly, different plasma parameters are found to play a significant role in the transition of oscillatory to monotonic shock waves or vice versa. Most importantly it is found that, the magnetosonic excitations obtained with spin-up and spin-down electrons are significantly different from the usual electron ion quantum plasma. The work presented is related to magnetosonic waves in dense astrophysical environments such as a pulsar magnetosphere and neutron stars.
Journal of the Physical Society of Japan, 2020
We investigate the wave propagation characteristics and head-on collision of low-frequency magnet... more We investigate the wave propagation characteristics and head-on collision of low-frequency magnetosonic waves in a dissipative plasma consisting of classical ions and degenerate inertia-less spin-up and spin-down electrons. Spin features are modeled via the macroscopic spin magnetization current and spin pressure. Employing the extended Poincare-Lighthill-Kuo perturbation method, a couple of Korteweg-de Vries-Burgers (KdVB) type equations are derived for small amplitude counter traveling magnetosonic waves. We traced out the parametric regime of compressive and rarefactive magnetosonic waves based on our plasma configurations. The phase shift effects of magnetosonic shock waves post-collision are also shown. We observe that the colliding process and phase shifts are significantly affected by various system configurational parameters, such as spin polarization, quantum diffraction, spin magnetization energy, and magnetic diffusivity. Importantly, we noticed that the head-on collision of two counter traveling magnetosonic shocks waves bearing spin polarization effect is significantly different from the usual electron-ion quantum plasma case. The work presented is related to the study of collective phenomena related to magnetosonic wave interaction, which is of great importance in dense astrophysical environments.