Eur. Phys. J. D 64, 419-426 (2011)
https://doi.org/10.1140/epjd/e2011-20374-x

Regular Article

Arbitrary magnetosonic solitary waves in spin 1/2 degenerate quantum plasma

¹ TPPD, PINSTECH, P.O. Nilore, 44000 Islamabad, Pakistan
² School of Physics, University of Sydney, 2006 NSW, Australia

^a e-mail: msherpao@gmail.com

Received: 24 June 2011
Received in final form: 4 August 2011
Published online: 6 October 2011

Abstract

Linear and nonlinear compressional magnetosonic waves are studied in magnetized degenerate spin-1/2 Fermi plasmas. Starting from the basic equations of a quantum magnetoplasma we develop the system of quantum magnetohydrodynamic (QMHD) equations. Spin effects are incorporated via spin force and macroscopic spin magnetization current. Sagdeev potential approach is employed to derive the nonlinear energy integral equation which admits the rarefactive solitary structure in the subAlfvenic region. The quantum diffraction due to Bohm potential does not affect the amplitude of soliton but has a direct effect on its width. The width of soliton is broadened with the increase in the quantization of the system due to quantum diffraction. However, the nonlinear wave amplitude is reduced with the increase in the value of magnetization energy due to electron spin-1/2 effects. The degeneracy effect due to quantum plasma beta enhances the amplitude of magnetosonic soliton. The importance of the work relevant to compact astrophysical bodies is pointed out.