Data and input supporting: Evolutionary dynamics of counter-helical magnetic flux ropes
Data files
Nov 13, 2024 version files 2.20 GB
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CH1d5TR.dat
349.88 KB
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CH1d5Tx0.dat
702.69 KB
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CH1d5Tx1.dat
1.26 MB
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CH3dT00h.zip
150.30 MB
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CL3dT00h.zip
150.31 MB
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CS3dT00h.zip
249.63 MB
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CS3dT01h.zip
461.42 MB
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CS3dT02h.zip
505.41 MB
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CS3dT03h.zip
546.38 MB
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README.md
2 KB
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RL3dT00h.zip
135.86 MB
Abstract
Upon interaction, a pair of magnetic flux ropes can merge to form a new pair, each consisting of opposite helicity along their axis. Magnetic helicity along such new structures may annihilate and release the energy of the azimuthal magnetic field. In this study, we model the deformation dynamics of such structures within the solar wind at 1 AU. The perturbation front of deformation propagates along the rope axis at approximately the Alfvén speed. However, the process to annihilate 90% of the azimuthal components is much slower and is affected by the screw pitch of the magnetic field. Such a deformation process causes the plasma in the transition region between the two opposite chiralities to spin about the rope axis, and plasma heating is discussed accordingly. Our results provide insights for estimating the lifetimes of such flux ropes, facilitating observational efforts to identify them. This process may also apply to the behavior of magnetic flux ropes in other space and astronomical plasma environments.
Description of the data and file structure
These data are used to plot figures 1-7
Each data is in a zip file.
Data format: ASCII
data files: CS3dT0h.zip to CS3dT03h.zip: 3-D SK type MFR models at t=00, 01, 02, and 03h, as indicated in file names
RL3dT00h.zip: 3d initial condition for Figure 2a, 3a.
CL3dT00h.zip: 3d initial condition for Figure 2b, 3b.
CH3dT00h.zip: 3d initial condition for Figure 2c, 3c.
CH1d5TR.dat: line plot data for Figure8a
CH1d5Tx0.dat: line plot data for Figure7b
CH1d5Tx1.dat: line plot data for Figure8b
VARIABLES = “Rho [amu/cm^3]”
“U_x [km/s]” ”U_y [km/s]” ”U_z [km/s]”
“B_x [nT]” ”B_y [nT]” ”B_z [nT]”
“P [nPa]” ”J_x [`mA/m^2]" "J_y [
mA/m^2]" "J_z [
mA/m^2]”
“x [Mm]” ”y [Mm]” ”z [Mm]”
`mA is miuA, 1e-6Amp
These data are generated by simulating the time-evolution of a counter-helical magnetic flux rope initially in the solar wind.
More detailed description please refer to the ApJ paper with the same title and author list.
Parameters used to run the simulation:
Table 1. Parameters And Characteristic Scales in The Model, based on 1 AU nominal solar wind characteristics.
Parameters | Values | Scales* | Values |
---|---|---|---|
Plasma density n (/cc) | 5 | Ion inertial length di (Mm) | 0.1 |
Initial velocity shear u0 (km/s) | 0 | Proton Gyro radius rg (Mm) | 0.1 |
Plasma temperature T (K) | 4´105 | Thermal velocity vth (km/s) | 60 |
Max field B0 (nT) | 9 | Alfvén Speed VA (km/s) | 50 |
MFR Radius R0 (Mm) | 127 | Sound Speed Cs (km/s) | 45 |
MFR traverse time (Minutes) | 10 | Plasma b | ~1 |
Normalized pitch q | 4 | Domain Size (Mm) | 2000 |
Ideal MHD simulation of the evolution of counter-helical flux ropes interacting in the 1Au solar wind.
BATS-R-Us code is used to simulate this evolution (SWMF, 2024):
SWMF. (2024). University of Michigan space weather modeling framework (SWMF) [Software]. https://clasp.engin.umich.edu/research/theory-computational-methods/swmf-downloadable-software/
The data file is stored on Dryad, with input parameters on Zenodo.
We want to thank the American Astronomical Society (AAS) Data Editor and Dryad editors for their assistance with presenting this submission.