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Related papers: Nonlinear force-free coronal magnetic stereoscopy

200 papers

We study the magnetic field and current structure associated with a coronal loop. Through this we investigate to what extent the assumptions of a force-free magnetic field break down and where they might be justified. We analyse a 3D MHD…

Solar and Stellar Astrophysics · Physics 2017-12-05 Jörn Warnecke , Feng Chen , Sven Bingert , Hardi Peter

Photospheric magnetic vector maps from two different instruments are used to model the nonlinear force-free coronal magnetic field above an active region. We use vector maps inferred from polarization measurements of the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2015-06-15 J. K. Thalmann , S. K. Tiwari , T. Wiegelmann

The solar magnetic field is key to understanding the physical processes in the solar atmosphere. Nonlinear force-free codes have been shown to be useful in extrapolating the coronal field from underlying vector boundary data [see Schrijver…

Astrophysics · Physics 2008-01-21 T. Wiegelmann , J. K. Thalmann , C. J. Schrijver , M. L. DeRosa , T. R. Metcalf

The variation of the vector magnetic field along structures in the solar corona remains unmeasured. Using a unique combination of spectropolarimetry and stereoscopy, we infer and compare the vector magnetic field structure and…

Solar and Stellar Astrophysics · Physics 2016-12-14 Thomas A. Schad , Matthew J. Penn , Haosheng Lin , Philip G. Judge

Global magnetic field models use as input synoptic data, which usually show "aging effects" as the longitudinal 360{\deg} information is not obtained simultaneously. Especially during times of increased solar activity, the evolution of the…

Solar and Stellar Astrophysics · Physics 2021-10-04 Stephan G. Heinemann , Manuela Temmer , Stefan J. Hofmeister , Aleksandar Stojakovic , Laurent Gizon , Dan Yang

The Solar Orbiter mission, with an orbit outside the Sun Earth line and leaving the ecliptic plane, opens up opportunities for the combined analysis of measurements obtained by solar imagers and spectrometers. For the first time, different…

Solar and Stellar Astrophysics · Physics 2021-11-24 O. Podladchikova , L. Harra , K. Barczynski , C. H. Mandrini , F. Auchere , D. Berghmans , E. Buchlin , L. Dolla , M. Mierla , S. Parenti , L. Rodriguez

We investigate the change in stellar magnetic topology across the fully-convective boundary and its effects on coronal properties. We consider both the magnitude of the open flux that influences angular momentum loss in the stellar wind and…

Solar and Stellar Astrophysics · Physics 2012-07-11 Pauline Lang , Moira Jardine , Jean-Francois Donati , Julien Morin , Aline Vidotto

With the development of new instrumentation providing measurements of solar photospheric vector magnetic fields, we need to develop our understanding of the effects of current density on coronal magnetic field configurations. The object is…

Astrophysics · Physics 2009-11-13 S. Regnier , E. R. Priest

Optical observations of solar corona provide key information on its magnetic geometry. The large-scale open field of the corona plays an important role in shaping the ambient solar wind and constraining the propagation dynamics of the…

Solar and Stellar Astrophysics · Physics 2025-06-19 Vadim M. Uritsky , Christopher E. Rura , Cooper Downs , Shaela I. Jones , Charles Nickolos Arge , Nathalia Alzate

The coronal magnetic field cannot be directly observed, but in principle it can be reconstructed from the comparatively well observed photospheric magnetic field. A popular approach uses a nonlinear force-free model. Non-magnetic forces at…

Solar and Stellar Astrophysics · Physics 2016-10-28 S. A. Gilchrist , M. S. Wheatland

The coronal magnetic field plays a fundamental role in governing coronal activities, driving space-weather events, and shaping the heliosphere. Due to a lack of direct observations, extrapolation models such as the Potential Field Source…

Solar and Stellar Astrophysics · Physics 2026-04-02 Ziqi Wu , Jiansen He , Chuanpeng Hou , Tom van Doorsselaere , Rui Zhuo , Tianhang Chen , Liping Yang , David Pontin , Daniel Verscharen , Fang Shen

We demonstrate the sensitivity of magnetic energy and helicity computations regarding the quality of the underlying coronal magnetic field model. We apply the method of Wiegelmann & Inhester (2010) to a series of SDO/HMI vector…

Solar and Stellar Astrophysics · Physics 2019-07-24 Julia K. Thalmann , Luis Linan , Etienne Pariat , Gherardo Valori

The solar atmosphere being magnetic in nature, the understanding of the structure and evolution of the magnetic field in different regions of the solar atmosphere has been an important task over the past decades. This task has been made…

Solar and Stellar Astrophysics · Physics 2015-06-16 S. Regnier

We use rotation stereoscopy to estimate the height of a steady-state solar feature relative to the photosphere, based on its apparent motion in the image plane recorded over several days of observation. The stereoscopy algorithm is adapted…

Solar and Stellar Astrophysics · Physics 2015-05-28 Gelu M. Nita , Gregory D. Fleishman , Ju Jing , Sergey V. Lesovoi , Vladimir M. Bogod , Leonid V. Yasnov , Haimin Wang , Dale E. Gary

We present a careful assess of the forced field extrapolation using Solar Dynamics Observatory/Helioseismic and Magnetic Imager (SDO/HMI) magnetogram. The convergence property is checked by several metrics. The extrapolated field lines…

Solar and Stellar Astrophysics · Physics 2017-03-22 Xiaoshuai Zhu , Huaning Wang , Zhanle Du , Han He

Understanding the three-dimensional evolution of coronal magnetic fields during solar flares remains challenging due to the lack of direct coronal field measurements. Here we combine data-driven MHD simulations of NOAA AR 11158 (Fan et al.,…

Solar and Stellar Astrophysics · Physics 2026-01-08 Maria D. Kazachenko , Yuhong Fan , Andrey N. Afanasyev

The rapid, irreversible change of the photospheric magnetic field has been recognized as an important element of the solar flare process. This Letter reports such a rapid change of magnetic fields during the 2011 February 13 M6.6 flare in…

Solar and Stellar Astrophysics · Physics 2015-06-03 Chang Liu , Na Deng , Rui Liu , Jeongwoo Lee , Thomas Wiegelmann , Ju Jing , Yan Xu , Shuo Wang , Haimin Wang

We performed a detailed analysis of the magnetic structure and asymmetric eruption of a large (about 500 Mm) inverse S-shaped filament partially located in AR 13229 on February 24, 2023. We linked the filament's pre-eruptive magnetic…

Solar and Stellar Astrophysics · Physics 2025-08-26 Stefan Purkhart , Astrid M. Veronig , Robert Jarolim , Karin Dissauer , Julia K. Thalmann

The 3D structure of an active region (AR) filament is studied using nonlinear force-free field (NLFFF) extrapolations based on simultaneous observations at a photospheric and a chromospheric height. To that end, we used the Si I 10827 \AA\…

Solar and Stellar Astrophysics · Physics 2015-06-03 L. Yelles Chaouche , C. Kuckein , V. Martínez Pillet , F. Moreno-Insertis

Context. On the sun, the magnetic field vector is measured routinely only in the photosphere. By using these photospheric measurements as boundary condition, we developed the magnetohydrostatic (MHS) extrapolation to model the solar…

Solar and Stellar Astrophysics · Physics 2019-11-20 Xiaoshuai Zhu , Thomas Wiegelmann
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