http://digitalrepository.fccollege.edu.pk/handle/123456789/96 Physics 2026-06-22T18:50:12Z http://digitalrepository.fccollege.edu.pk/handle/123456789/2603 Title: Brief Communication: A modified Korteweg–de Vries equation for Rossby–Khantadze waves in a sheared zonal flow of the ionospheric E layer Authors: Zafar Kahlon, Dr. Laila; Amir Shah, Dr. Hassan; David Kaladze, Tamaz; Tul Ain, Qura; Assad Bukhari, Syed Abstract: The system of non-linear equations for electromagnetic Rossby–Khantadze waves in a weakly ionized conductive ionospheric E-layer plasma with sheared zonal flow is given. Use of multiple-scale analysis allows reduction of an obtained set of equations to a (1C1)D non-linear modified KdV (mKdV) equation with cubic non-linearity describing the propagation of solitary Rossby–Khantadze solitons. Description: The system of non-linear equations for electromagnetic Rossby–Khantadze waves in a weakly ionized conductive ionospheric E-layer plasma with sheared zonal flow is given. Use of multiple-scale analysis allows reduction of an obtained set of equations to a (1C1)D non-linear modified KdV (mKdV) equation with cubic non-linearity describing the propagation of solitary Rossby–Khantadze solitons. 2024-01-01T00:00:00Z http://digitalrepository.fccollege.edu.pk/handle/123456789/2602 Title: Effect of trapping in coupled kinetic Alfven-acoustic waves in a partially degenerate plasma with quantizing magnetic !eld Authors: Zafar Kahlon, Dr. Laila; Masood, W; Iqbal, Zeeshan; Amir Shah, Dr. Hassan; A Bukhari, S; Asam, MT Abstract: Inclusion of a quantizing magnetic !eld in a partially degenerate plasma has interesting effects on the propagation of solitary and nonlinear periodic structures in coupled kinetic Alfven acoustic waves. In this paper, we use two-potential theory to investigate the nonlinear structures using Sagdeev potential approach and further analyze it using nonlinear dynamical methods. It is shown that the existence of solitary structure is sensitive to small temperature effects and quantizing magnetic !eld in a dense plasma with adiabatically trapped electrons. The work presented here is useful in understanding the low frequency wave propagation in a dense astrophysical environment like white dwarf stars and in low beta laboratory plasmas e.g. intense laser-plasma interactions. Description: Inclusion of a quantizing magnetic !eld in a partially degenerate plasma has interesting effects on the propagation of solitary and nonlinear periodic structures in coupled kinetic Alfven acoustic waves. In this paper, we use two-potential theory to investigate the nonlinear structures using Sagdeev potential approach and further analyze it using nonlinear dynamical methods. It is shown that the existence of solitary structure is sensitive to small temperature effects and quantizing magnetic !eld in a dense plasma with adiabatically trapped electrons. The work presented here is useful in understanding the low frequency wave propagation in a dense astrophysical environment like white dwarf stars and in low beta laboratory plasmas e.g. intense laser-plasma interactions. 2023-01-01T00:00:00Z http://digitalrepository.fccollege.edu.pk/handle/123456789/2190 Title: The impact of quantized magnetic pressure on the stimulated Brillouin scattering of electromagnetic waves Authors: Rozina, Ch; Maroosh, A; Poedts, S; Shah, H. A. Abstract: Within the frame work of Landau quantization theory of Fermi gas, we formulate here the exotic physics of magnetic stimulated Brillouin scattering instability (MSBS) arising due to the nonlinear interaction of high frequency electromagnetic waves(EMWs)with degenerate, strongly magnetized electron-ion plasma. Quantum magneto hydrodynamic model (QMHD)is followed to develop the basic differential equations of quantized magnetosonic waves(QMWs)in the presence of super strong magnetic (SSH) field, whereas Maxwell equations are used to derive the governing differential equation of pump EMWs. The nonlinear interaction of EMWs and QMWs is addressed by employing the phasor matching technique. The obtained dispersion relation of MSBS shows that for a fixed density of fermions, the SSH field alone suppresses the MSBS instability as a function of quantized magneto ion velocity (CHe) and the Alfven speed (VA) via three-wave decay and modulational instabilities. However, for particular condition the MSBS instability is found to increase as a function of SSH field. Next, the analytical results are verified numerically and graphically for soft x-rays in the environment of neutron star. The present MSBS analysis may be critical in neutron stars, radio pulsars and magnetars having super strong magnetic field i.e. even larger than the quantum threshold value i.e, H ∼ 4.4 × 1013G, or in any application where the enhancement or suppression of SBS may be important. 2023-08-16T00:00:00Z http://digitalrepository.fccollege.edu.pk/handle/123456789/2189 Title: Fast and slow magnetosonic shock waves in non-Maxwellian plasmas Authors: Izhar, Navaira; Qureshi, M.N.S.; Shi, J.K.; Shah, H. A. Abstract: Obliquely propagating nonlinear fast and slow magnetosonic wave modes in a hot non-Maxwellian dissipative plasma are investigated in the current work. Modified temperatures have been derived for the non-extensive Q- and (r, q)-distributions that correspond to the physical properties of such non-Maxwellian plasmas. The reductive perturbation technique has been employed to derive the linear dispersion relation (LDR) and Kadomstev-Petvashvilli-Burgers (KPB) equation for slow and fast magnetosonic wave modes in two dimensions. We then investigated the effect of non-extensive parameter Q, spectral indices (r, q) and kinematic viscosity ν on the LDR and nonlinear propagation of KPB shock profiles for both the slow and fast mode magnetosonic waves. We found that linear and nonlinear propagation of fast and slow magnetosonic wave modes have been considerably modified in such non-Maxwellian plasmas. The results presented here would depict a realistic picture of the propagation of linear and nonlinear fast and slow magnetosonic wave modes in non-Maxwellian plasmas. 2023-10-12T00:00:00Z