Optimization code with weighting function for the reconstruction of coronal magnetic fields

By T. Wiegelmann. 2008

379 citations recorded by the source corpus.

We developed a code for the reconstruction of nonlinear force-free and non-force-free coronal magnetic fields. The 3D magnetic field is computed numerically with the help of an optimization principle. The force-free and non-force-free codes are compiled in one program. The force-free approach needs photospheric vector magnetograms as input. The non-force-free code additionally requires the line-of-sight integrated coronal density distribution in combination with a tomographic inversion code. Previously the optimization approach has been used to compute magnetic fields using all six boundaries of a computational box. Here we extend this method and show how the coronal magnetic field can be reconstructed only from the bottom boundary, where the boundary conditions are measured with vector magnetographs. The program is planed for use within the Stereo mission.

Subfields: Astronomy and Astrophysics, Molecular Biology

View Paper: https://www.semanticscholar.org/paper/1328270fd195bc9a95800c16b627d820c724732f

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Citations in the corpus

The Helioseismic and Magnetic Imager (HMI) Investigation for the Solar Dynamics Observatory (SDO) (2012, methodology): “The optimization code for inference of non-linear force-free coronal magnetic fields is based on work by Wiegelmann (2004) and Wiegelmann, Inhester, and Sakurai (2006).”
Nonlinear Force-Free Modeling of Coronal Magnetic Fields Part I: A Quantitative Comparison of Methods (2006, methodology): “The fastest-converging, best-performing model for these analytical test cases is the Wheatland, Sturrock, and Roumeliotis (2000) optimization algorithm as implemented by Wiegelmann (2004).”
A CRITICAL ASSESSMENT OF NONLINEAR FORCE-FREE FIELD MODELING OF THE SOLAR CORONA FOR ACTIVE REGION 10953 (2009, methodology): “…field is evolved to minimize a volume integral such that, if it becomes zero, the field is divergence- and force-free (Wheatland et al. 2000; Wiegelmann 2004); (2) the evolutionary magnetofrictional method, which solves the magnetic induction equation using a velocity field that advances…”
Preprocessing of Vector Magnetograph Data for a Nonlinear Force-Free Magnetic Field Reconstruction (2006, methodology): “…1996; Amari et al., 1997; Yan and Sakurai, 2000; Wheatland et al., 2000; Wheatland, 2004; Régnier et al., 2002; Wiegelmann and Neukirch, 2003; Wiegelmann, 2004; Valori et al., 2005) is challenging both theoretically due to the non-linearity of the underlying mathematical problem and…”
Nonlinear Force-Free Modeling of Coronal Magnetic Fields. II. Modeling a Filament Arcade and Simulated Chromospheric and Photospheric Vector Fields (2008, methodology): “Wiegelmann: Weighted Optimization The details of the Wiegelmann method were described by Wiegelmann (2004) and summarized in our first NLFFF paper.”
Solar Force-free Magnetic Fields (2012, methodology): “Nevertheless, it was shown that the optimization method as proposed by Wheatland et al. (2000) and as implemented by Wiegelmann (2004) was the fastest-converging and best-performing one for this analytical test case.”
How Should One Optimize Nonlinear Force-Free Coronal Magnetic Field Extrapolations from SDO/HMI Vector Magnetograms? (2012, methodology): “We solve the force-free equations (1) - (3) by an optimization principle as proposed by (Wheatland, Sturrock, and Roumeliotis, 2000) and extended by (Wiegelmann, 2004; Wiegelmann and Inhester, 2010) in the form: L = ∫ V wf |(∇×B)×B|2 B2 + wd |∇ ·B|2 d3V 2The values refer to other Active Regions and…”
WHY IS THE GREAT SOLAR ACTIVE REGION 12192 FLARE-RICH BUT CME-POOR? (2015, methodology): “We study the coronal field by extrapolating a nonlinear force-free field (NLFFF; Wiegelmann 2004; Wiegelmann et al. 2006) and a potential field (PF; e.g., Sakurai 1989) from each vector magnetogram (Sun et al. 2012).”
EVOLUTION OF MAGNETIC FIELD AND ENERGY IN A MAJOR ERUPTIVE ACTIVE REGION BASED ON SDO/HMI OBSERVATION (2011, methodology): “We use an optimization-based NLFFF algorithm (Wiegelmann 2004) to extrapolate the coronal field from the magnetograms in a Cartesian domain.”
COEXISTING FLUX ROPE AND DIPPED ARCADE SECTIONS ALONG ONE SOLAR FILAMENT (2010, methodology): “The principle of the method is to minimize the objective function, L = ∫ V ω(x, y, z) [ B−2 | (∇ × B) × B |2 + | ∇ · B |2] dV, (1) where ω(x, y, z) is the weighting function (Wheatland et al. 2000; Wiegelmann 2004).”