Modulation of cylindrical (spherical) waves in a plasma with vortex electron distribution
Yükleniyor...
Dosyalar
Tarih
2018-07-01
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
American Institute of Physics Inc.
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
In the present work, employing cylindrically (spherically) symmetric field equations of a plasma consisting of a cold electron fluid, hot electrons obeying a trapped/vortex-like distribution and stationary ions, we studied the amplitude modulation of electron-acoustic waves. Due to the physical nature of the problem under investigation, the nonlinearity of the field equations is of order (3/2), which causes considerable difficulty in the analysis of modulation problems. To solve this difficulty, we expanded this nonlinear term into the Fourier cosine series of the phase function and obtained the modified cylindrical (spherical) nonlinear Schrodinger (NLS) equation. A consistent analysis for the modulational instability is presented and a criterion between the time parameter tau and the wave number K is established. In addition, motivated with the solitonic solution of modified NLS equation for planar case and utilizing the "weighted residual method," we proposed a harmonic wave of variable frequency with progressive wave amplitude to the evolution equation. It is found that the modified cylindrical (spherical) NLS equation assumes an envelope type of progressive wave solution in the sense weighted residual. The numerical results reveal that the amplitude of spherical wave is much larger than that of the cylindrical wave and that both amplitudes decrease with increasing time parameter tau. It is further observed that the wave profiles get distorted with progressing time.
Açıklama
Anahtar Kelimeler
Ion-acoustic-waves, De-vries Equation, Instability, Acoustics, Dust, Dust acoustic, Control nonlinearities, Electrons, Fourier series, Hot electrons, Modulation, Nonlinear equations, Spheres, Trapped ions, Electron acoustic waves, Electron distributions, Evolution equations, Modulational instability, Progressive wave solutions, Solitonic solutions, Variable frequencies, Weighted residual method
Kaynak
Physics of Plasmas
WoS Q Değeri
Q3
Scopus Q Değeri
Q1
Cilt
25
Sayı
7
Künye
Demiray, H. (2018). Modulation of cylindrical (spherical) waves in a plasma with vortex electron distribution. Physics of Plasmas, 25(7), 1-6. doi:10.1063/1.5040795
