On nonlinear evolution of lowfrequency Alfvén waves in weaklyexpanding solar wind plasmas
Abstract
A multidimensional nonlinear evolution equation for Alfvén waves in weaklyexpanding solar wind plasmas is derived by using the reductive perturbation method. The expansion of solar wind plasma parcels is modeled by an expanding box model, which includes the accelerating expansion. It is shown that the resultant equation agrees with the WentzelKramersBrillouin prediction of the lowfrequency Alfvén waves in the linear limit. In the cold and onedimensional limit, a modified derivative nonlinear Schrodinger equation is obtained. Direct numerical simulations are carried out to discuss the effect of the expansion on the modulational instability of monochromatic Alfvén waves and the propagation of Alfvén solitons. By using the instantaneous frequency, it is quantitatively shown that as far as the expansion rate is much smaller than wave frequencies, effects of the expansion are almost adiabatic. It is also confirmed that while shapes of Alfvén solitons temporally change due to the expansion, some of them can stably propagate after their collision in weaklyexpanding plasmas.
 Authors:
 Faculty of Human Development, University of Toyama, 3190 Toyama City, Toyama 9308555 (Japan)
 Publication Date:
 OSTI Identifier:
 22408092
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ALFVEN WAVES; BOX MODELS; COLLISIONS; COMPUTERIZED SIMULATION; INSTABILITY; MATHEMATICAL EVOLUTION; MONOCHROMATIC RADIATION; NONLINEAR PROBLEMS; ONEDIMENSIONAL CALCULATIONS; PERTURBATION THEORY; PLASMA; SCHROEDINGER EQUATION; SOLAR WIND; SOLITONS; WKB APPROXIMATION
Citation Formats
Nariyuki, Y. On nonlinear evolution of lowfrequency Alfvén waves in weaklyexpanding solar wind plasmas. United States: N. p., 2015.
Web. doi:10.1063/1.4908544.
Nariyuki, Y. On nonlinear evolution of lowfrequency Alfvén waves in weaklyexpanding solar wind plasmas. United States. doi:10.1063/1.4908544.
Nariyuki, Y. 2015.
"On nonlinear evolution of lowfrequency Alfvén waves in weaklyexpanding solar wind plasmas". United States.
doi:10.1063/1.4908544.
@article{osti_22408092,
title = {On nonlinear evolution of lowfrequency Alfvén waves in weaklyexpanding solar wind plasmas},
author = {Nariyuki, Y.},
abstractNote = {A multidimensional nonlinear evolution equation for Alfvén waves in weaklyexpanding solar wind plasmas is derived by using the reductive perturbation method. The expansion of solar wind plasma parcels is modeled by an expanding box model, which includes the accelerating expansion. It is shown that the resultant equation agrees with the WentzelKramersBrillouin prediction of the lowfrequency Alfvén waves in the linear limit. In the cold and onedimensional limit, a modified derivative nonlinear Schrodinger equation is obtained. Direct numerical simulations are carried out to discuss the effect of the expansion on the modulational instability of monochromatic Alfvén waves and the propagation of Alfvén solitons. By using the instantaneous frequency, it is quantitatively shown that as far as the expansion rate is much smaller than wave frequencies, effects of the expansion are almost adiabatic. It is also confirmed that while shapes of Alfvén solitons temporally change due to the expansion, some of them can stably propagate after their collision in weaklyexpanding plasmas.},
doi = {10.1063/1.4908544},
journal = {Physics of Plasmas},
number = 2,
volume = 22,
place = {United States},
year = 2015,
month = 2
}

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