Three-dimensional MHD simulation of CMEs in three-dimensional background solar wind with the self-consistent structure on the source surface as input: Numerical simulation of the January 1997 Sun-Earth connection event

Three-dimensional (3-d) magnetohydrodynamics (MHD) modeling is a key method for studying the interplanetary solar wind. In this paper, we introduce a new 3-d MHD solar wind model driven by the self-consistent boundary condition obtained from multiple observations and the Artificial Neural Network (ANN) machine learning technique. At the inner boundary, the magnetic field is derived using the magnetogram and potential field source surface extrapolation; the electron density is derived from the polarized brightness (pB) observations, the velocity can be deduced by an ANN using both the magnetogram and pB observations, and the temperature is derived from the magnetic field and electron density by a self-consistent method. Then, the 3-d interplanetary solar wind from CR2057 to CR2062 is modeled by the new model with the self-consistent boundary conditions. The modeling results present various observational characteristics at different latitudes, and are in better agreement with both the OMNI and Ulysses observations compared to our previous MHD model based only on photospheric magnetic field observations.

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On the self-consistent algorithm for numerical simulation of the global geomagnetic disturbances and associated electric current spreading to low latitudes

IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229) ◽

10.1109/aps.2001.960048 ◽

2002 ◽

Author(s):

L. Alperorich ◽

B. Fidel

Keyword(s):

Numerical Simulation ◽

Electric Current ◽

The Self ◽

Geomagnetic Disturbances ◽

Current Spreading ◽

Low Latitudes ◽

Self Consistent

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Full compressible 3D MHD simulation of solar wind

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3533 ◽

2020 ◽

Vol 500 (4) ◽

pp. 4779-4787

Author(s):

Takuma Matsumoto

Keyword(s):

Solar Wind ◽

Transition Region ◽

Solar Physics ◽

Mass Loss Rate ◽

Three Dimensional ◽

Lower Atmosphere ◽

Fast Solar Wind ◽

Solar Mass ◽

Mhd Simulation ◽

Driving Mechanisms

ABSTRACT Identifying the heating mechanisms of the solar corona and the driving mechanisms of solar wind are key challenges in understanding solar physics. A full three-dimensional compressible magnetohydrodynamic (MHD) simulation was conducted to distinguish between the heating mechanisms in the fast solar wind above the open field region. Our simulation describes the evolution of the Alfvénic waves, which includes the compressible effects from the photosphere to the heliospheric distance s of 27 solar radii (R⊙). The hot corona and fast solar wind were reproduced simultaneously due to the dissipation of the Alfvén waves. The inclusion of the transition region and lower atmosphere enabled us to derive the solar mass-loss rate for the first time by performing a full three-dimensional compressible MHD simulation. The Alfvén turbulence was determined to be the dominant heating mechanism in the solar wind acceleration region (s > 1.3 R⊙), as suggested by previous solar wind models. In addition, shock formation and phase mixing are important below the lower transition region (s < 1.03 R⊙) as well.

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