2024-03-29T07:08:11Z
https://nagoya.repo.nii.ac.jp/oai
oai:nagoya.repo.nii.ac.jp:00023130
2023-01-16T04:45:35Z
879:880:881
MHD-IPS analysis of relationship among solar wind density, temperature, and flow speed
Hayashi, Keiji
68578
Tokumaru, Munetoshi
68579
Fujiki, Ken’ichi
68580
The solar wind properties near the Sun are a decisive factor of properties in the rest of heliosphere. As such, determining realistic plasma density and temperature near the Sun is very important in models for solar wind, specifically magnetohydrodynamics (MHD) models. We had developed a tomographic analysis to reconstruct three-dimensional solar wind structures that satisfy line-of-sight-integrated solar wind speed derived from the interplanetary scintillation (IPS) observation data and nonlinear MHD equations simultaneously. In this study, we report a new type of our IPS-MHD tomography that seeks three-dimensional MHD solution of solar wind, matching additionally near-Earth and/or Ulysses in situ measurement data for each Carrington rotation period. In this new method, parameterized relation functions of plasma density and temperature at 50 Rs are optimized through an iterative forward model minimizing discrepancy with the in situ measurements. Satisfying three constraints, the derived 50 Rs maps of plasma quantities provide realistic observation-based information on the state of solar wind near the Sun that cannot be well determined otherwise. The optimized plasma quantities exhibit long-term variations over the solar cycles 21 to 24. The differences in plasma quantities derived from the optimized and original IPS-MHD tomography exhibit correlations with the source-surface magnetic field strength, which can in future give new quantitative constrains and requirements to models of coronal heating and acceleration.
journal article
Wiley
2016-08
application/pdf
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
8
121
7367
7384
http://doi.org/10.1002/2016JA022750
http://hdl.handle.net/2237/25324
2169-9402
https://nagoya.repo.nii.ac.jp/record/23130/files/Hayashi_et_al-2016-Journal_of_Geophysical_Research_Space_Physics.pdf
eng
https://doi.org/10.1002/2016JA022750
© 2016 American Geophysical Union