Solar force-free magnetic fields
نویسندگان
چکیده
Abstract The structure and dynamics of the solar corona is dominated by magnetic field. In most areas in forces are so dominant that all non-magnetic such as plasma pressure gradients gravity can be neglected lowest order. This model assumption called force-free field assumption, Lorentz force vanishes. obtained either vanishing electric currents (leading to potential fields) or co-aligned with lines. First we discuss a mathematically simpler approach proportional one global constant, so-called linear approximation. generic case, however, relationship between fields nonlinear analytic solutions have been only found for special cases, like 1D 2D configurations. For constructing realistic coronal models 3D, sophisticated numerical computations required boundary conditions must from measurements vector photosphere. currently large area research, accurate photospheric available ground-based observatories Synoptic Optical Long-term Investigations Sun Daniel K. Inouye Solar Telescope (DKIST) space-born, e.g., Hinode Dynamics Observatory. If obtain calculate free energy corona, quantity which important prediction flares mass ejections. Knowledge 3D lines also help us interpret other observations, EUV images radiating plasma.
منابع مشابه
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ژورنال
عنوان ژورنال: Living Reviews in Solar Physics
سال: 2021
ISSN: ['2367-3648', '1614-4961']
DOI: https://doi.org/10.1007/s41116-020-00027-4