Chromospheric Magnetic Field: A Comparison of He i 10830 Å Observations with Nonlinear Force-free Field Extrapolation

@article{Kawabata2020ChromosphericMF,
  title={Chromospheric Magnetic Field: A Comparison of He i 10830 Å Observations with Nonlinear Force-free Field Extrapolation},
  author={Yusuke Kawabata and Andr{\'e}s Asensio Ramos and Satoshi Inoue and Toshifumi Shimizu},
  journal={arXiv: Solar and Stellar Astrophysics},
  year={2020}
}
The nonlinear force-free field (NLFFF) modeling has been extensively used to infer the three-dimensional (3D) magnetic field in the solar corona. One of the assumptions in the NLFFF extrapolation is that the plasma beta is low, but this condition is considered to be incorrect in the photosphere. We examine direct measurements of the chromospheric magnetic field in two active regions through spectropolarimetric observations at He I 10830 A, which are compared with the potential fields and NLFFFs… Expand
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