Data-Optimized Coronal Field Model: I. Proof of Concept

Abstract

Deriving the strength and direction of the three-dimensional (3D) magnetic field in the solar atmosphere is fundamental for understanding its dynamics. Volume information on the magnetic field mostly relies on coupling 3D reconstruction methods with photospheric and/or chromospheric surface vector magnetic fields. Infrared coronal polarimetry could provide additional information to better constrain magnetic field reconstructions. However, combining such data with reconstruction methods is challenging, e.g., because of the optical-thinness of the solar corona and the lack and limitations of stereoscopic polarimetry. To address these issues, we introduce the Data-Optimized Coronal Field Model (DOCFM) framework, a model-data fitting approach that combines a parametrized 3D generative model, e.g., a magnetic field extrapolation or a magnetohydrodynamic model, with forward modeling of coronal data. We test it with a parametrized flux rope insertion method and infrared coronal polarimetry where synthetic observations are created from a known "ground truth" physical state. We show that this framework allows us to accurately retrieve the ground truth 3D magnetic field of a set of force-free field solutions from the flux rope insertion method. In observational studies, the DOCFM will provide a means to force the solutions derived with different reconstruction methods to satisfy additional, common, coronal constraints. The DOCFM framework therefore opens new perspectives for the exploitation of coronal polarimetry in magnetic field reconstructions and for developing new techniques to more reliably infer the 3D magnetic fields that trigger solar flares and coronal mass ejections.

14 pages, 6 figures; Accepted for publication in ApJ

References in corpus (10)

• Optimization code with weighting function for the reconstruction of coronal magnetic fields
• The Magnetic Field in the Solar Atmosphere
• Modelling the Global Solar Corona: Filament Chirality Observations and Surface Simulations
• How did a Major Confined Flare Occur in Super Solar Active Region 12192?
• A global view of velocity fluctuations in the corona below 1.3 $R_{\odot }$ with CoMP
• Regularized Biot-Savart Laws for Modeling Magnetic Flux Ropes
• Coronal cavities: observations and implications for the magnetic environment of prominences
• Diagnostics of Coronal Magnetic Fields Through the Hanle Effect in UV and IR Lines
• Magnetic nulls and super-radial expansion in the solar corona
• ROAM: a Radial-basis-function Optimization Approximation Method for diagnosing the three-dimensional coronal magnetic field