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Title: Study of localized structures of kinetic Alfvén wave and generation of turbulence

Abstract

Localization of kinetic Alfvén waves (KAW) due to ponderomotive nonlinearity can be regarded as an important mechanism for heating the space plasmas. The present paper investigates the effect of background density fluctuations on the formation of large amplitude localized structures and turbulent spectrum of KAW applicable to magnetopause. The dynamical equations are derived, taking into account the ponderomotive nonlinearity of the KAW as well as the background fluctuations which are in the form of ion acoustic waves. The system is studied numerically as well as semi-analytically. The results reveal that the presence of density fluctuations affects the formation of localized structures. These fluctuations affecting the localization of KAW may also affect heating and acceleration of plasma. Respective turbulent scaling for the different amplitude of background fluctuations has also been studied. The relevance of the numerical results has been discussed with the THEMIS observations near the magnetopause [C. Chaston et al., Geophys. Res. Lett. 35, L17S08 (2008)].

Authors:
; ;  [1]
  1. Centre for Energy Studies, Indian Institute of Technology Delhi, Delhi-110016 (India)
Publication Date:
OSTI Identifier:
22490929
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 6; 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; ACCELERATION; ALFVEN WAVES; AMPLITUDES; HEATING; ION ACOUSTIC WAVES; MAGNETOPAUSE; NONLINEAR PROBLEMS; PLASMA; PONDEROMOTIVE FORCE; SPECTRA; TURBULENCE; TURBULENT FLOW

Citation Formats

Kumari, Anju, E-mail: anju.agrawal0986@gmail.com, Sharma, R. P., E-mail: rpsharma@ces.iitd.ac.in, and Yadav, Nitin, E-mail: nitnyadv@gmail.com. Study of localized structures of kinetic Alfvén wave and generation of turbulence. United States: N. p., 2015. Web. doi:10.1063/1.4922678.
Kumari, Anju, E-mail: anju.agrawal0986@gmail.com, Sharma, R. P., E-mail: rpsharma@ces.iitd.ac.in, & Yadav, Nitin, E-mail: nitnyadv@gmail.com. Study of localized structures of kinetic Alfvén wave and generation of turbulence. United States. doi:10.1063/1.4922678.
Kumari, Anju, E-mail: anju.agrawal0986@gmail.com, Sharma, R. P., E-mail: rpsharma@ces.iitd.ac.in, and Yadav, Nitin, E-mail: nitnyadv@gmail.com. Mon . "Study of localized structures of kinetic Alfvén wave and generation of turbulence". United States. doi:10.1063/1.4922678.
@article{osti_22490929,
title = {Study of localized structures of kinetic Alfvén wave and generation of turbulence},
author = {Kumari, Anju, E-mail: anju.agrawal0986@gmail.com and Sharma, R. P., E-mail: rpsharma@ces.iitd.ac.in and Yadav, Nitin, E-mail: nitnyadv@gmail.com},
abstractNote = {Localization of kinetic Alfvén waves (KAW) due to ponderomotive nonlinearity can be regarded as an important mechanism for heating the space plasmas. The present paper investigates the effect of background density fluctuations on the formation of large amplitude localized structures and turbulent spectrum of KAW applicable to magnetopause. The dynamical equations are derived, taking into account the ponderomotive nonlinearity of the KAW as well as the background fluctuations which are in the form of ion acoustic waves. The system is studied numerically as well as semi-analytically. The results reveal that the presence of density fluctuations affects the formation of localized structures. These fluctuations affecting the localization of KAW may also affect heating and acceleration of plasma. Respective turbulent scaling for the different amplitude of background fluctuations has also been studied. The relevance of the numerical results has been discussed with the THEMIS observations near the magnetopause [C. Chaston et al., Geophys. Res. Lett. 35, L17S08 (2008)].},
doi = {10.1063/1.4922678},
journal = {Physics of Plasmas},
number = 6,
volume = 22,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}
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