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Title: Multiscale Pressure-Balanced Structures in Three-dimensional Magnetohydrodynamic Turbulence

Abstract

Observations of solar wind turbulence indicate the existence of multiscale pressure-balanced structures (PBSs) in the solar wind. In this work, we conduct a numerical simulation to investigate multiscale PBSs and in particular their formation in compressive magnetohydrodynamic turbulence. By the use of the higher-order Godunov code Athena, a driven compressible turbulence with an imposed uniform guide field is simulated. The simulation results show that both the magnetic pressure and the thermal pressure exhibit a turbulent spectrum with a Kolmogorov-like power law, and that in many regions of the simulation domain they are anticorrelated. The computed wavelet cross-coherence spectra of the magnetic pressure and the thermal pressure, as well as their space series, indicate the existence of multiscale PBSs, with the small PBSs being embedded in the large ones. These multiscale PBSs are likely to be related to the highly oblique-propagating slow-mode waves, as the traced multiscale PBS is found to be traveling in a certain direction at a speed consistent with that predicted theoretically for a slow-mode wave propagating in the same direction.

Authors:
; ;  [1]; ; ;  [2];  [3];  [4];  [5]
  1. SIGMA Weather Group, State Key Laboratory for Space Weather, National Space Science Center, Chinese Academy of Sciences, 100190, Beijing (China)
  2. School of Earth and Space Sciences, Peking University, 100871 Beijing (China)
  3. Theoretical Division, MS B284, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)
  4. Institute for Experimental and Applied Physics, Christian Albrechts University at Kiel, D-24118 Kiel (Germany)
  5. School of Space and Environment, Beihang University, 100191 Beijing (China)
Publication Date:
OSTI Identifier:
22663848
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 836; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BALANCES; COMPUTERIZED SIMULATION; MAGNETOHYDRODYNAMICS; SOLAR WIND; SPACE; SPECTRA; THREE-DIMENSIONAL CALCULATIONS; TURBULENCE; VELOCITY

Citation Formats

Yang, Liping, Zhang, Lei, Feng, Xueshang, He, Jiansen, Tu, Chuanyi, Wang, Linghua, Li, Shengtai, Marsch, Eckart, and Wang, Xin, E-mail: jshept@gmail.com. Multiscale Pressure-Balanced Structures in Three-dimensional Magnetohydrodynamic Turbulence. United States: N. p., 2017. Web. doi:10.3847/1538-4357/836/1/69.
Yang, Liping, Zhang, Lei, Feng, Xueshang, He, Jiansen, Tu, Chuanyi, Wang, Linghua, Li, Shengtai, Marsch, Eckart, & Wang, Xin, E-mail: jshept@gmail.com. Multiscale Pressure-Balanced Structures in Three-dimensional Magnetohydrodynamic Turbulence. United States. doi:10.3847/1538-4357/836/1/69.
Yang, Liping, Zhang, Lei, Feng, Xueshang, He, Jiansen, Tu, Chuanyi, Wang, Linghua, Li, Shengtai, Marsch, Eckart, and Wang, Xin, E-mail: jshept@gmail.com. Fri . "Multiscale Pressure-Balanced Structures in Three-dimensional Magnetohydrodynamic Turbulence". United States. doi:10.3847/1538-4357/836/1/69.
@article{osti_22663848,
title = {Multiscale Pressure-Balanced Structures in Three-dimensional Magnetohydrodynamic Turbulence},
author = {Yang, Liping and Zhang, Lei and Feng, Xueshang and He, Jiansen and Tu, Chuanyi and Wang, Linghua and Li, Shengtai and Marsch, Eckart and Wang, Xin, E-mail: jshept@gmail.com},
abstractNote = {Observations of solar wind turbulence indicate the existence of multiscale pressure-balanced structures (PBSs) in the solar wind. In this work, we conduct a numerical simulation to investigate multiscale PBSs and in particular their formation in compressive magnetohydrodynamic turbulence. By the use of the higher-order Godunov code Athena, a driven compressible turbulence with an imposed uniform guide field is simulated. The simulation results show that both the magnetic pressure and the thermal pressure exhibit a turbulent spectrum with a Kolmogorov-like power law, and that in many regions of the simulation domain they are anticorrelated. The computed wavelet cross-coherence spectra of the magnetic pressure and the thermal pressure, as well as their space series, indicate the existence of multiscale PBSs, with the small PBSs being embedded in the large ones. These multiscale PBSs are likely to be related to the highly oblique-propagating slow-mode waves, as the traced multiscale PBS is found to be traveling in a certain direction at a speed consistent with that predicted theoretically for a slow-mode wave propagating in the same direction.},
doi = {10.3847/1538-4357/836/1/69},
journal = {Astrophysical Journal},
number = 1,
volume = 836,
place = {United States},
year = {Fri Feb 10 00:00:00 EST 2017},
month = {Fri Feb 10 00:00:00 EST 2017}
}
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