Three-Dimensional Coronal Magnetic Field Based on the Photospheric Magnetic Field by Hinode/SP Observation

AbstractMagnetism defines the complex and dynamic solar corona. Twists and tangles in coronal magnetic fields build up energy and ultimately erupt, hurling plasma into interplanetary space. These coronal mass ejections (CMEs) are transient riders on the ever-outflowing solar wind, which itself possesses a three-dimensional morphology shaped by the global coronal magnetic field. Coronal magnetism is thus at the heart of any understanding of the origins of space weather at the Earth. However, we have historically been limited by the difficulty of directly measuring the magnetic fields of the corona, and have turned to observations of coronal plasma to trace out magnetic structure. This approach is complicated by the fact that plasma temperatures and densities vary among coronal magnetic structures, so that looking at any one wavelength of light only shows part of the picture. In fact, in some regimes it is the lack of plasma that is a significant indicator of the magnetic field. Such a case is the coronal cavity: a dark, elliptical region in which strong and twisted magnetism dwells. I will elucidate these enigmatic features by presenting observations of coronal cavities in multiple wavelengths and from a variety of observing vantages, including unprecedented coronal magnetic field measurements now being obtained by the Coronal Multichannel Polarimeter (CoMP). These observations demonstrate the presence of twisted magnetic fields within cavities, and also provide clues to how and why cavities ultimately erupt as CMEs.

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ROAM: A Radial-Basis-Function Optimization Approximation Method for Diagnosing the Three-Dimensional Coronal Magnetic Field

Frontiers in Astronomy and Space Sciences ◽

10.3389/fspas.2016.00024 ◽

2016 ◽

Vol 3 ◽

Cited By ~ 9

Author(s):

Kevin Dalmasse ◽

Douglas W. Nychka ◽

Sarah E. Gibson ◽

Yuhong Fan ◽

Natasha Flyer

Keyword(s):

Magnetic Field ◽

Radial Basis Function ◽

Approximation Method ◽

Basis Function ◽

Three Dimensional ◽

Coronal Magnetic Field ◽

Function Optimization ◽

Radial Basis

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Diagnostics of plasma jets in the solar corona

Solnechno-Zemnaya Fizika ◽

10.12737/szf-72202101 ◽

2021 ◽

Vol 7 (2) ◽

pp. 3-11

Author(s):

Sergey Anfinogentov ◽

Tatyana Kaltman ◽

Alexey Stupishin ◽

Valery Nakariakov ◽

Maria Lukitcheva

Keyword(s):

Magnetic Field ◽

Solar Corona ◽

Extreme Ultraviolet ◽

Three Dimensional ◽

Statistical Processing ◽

Coronal Magnetic Field ◽

Plasma Jets ◽

Dimensional Structure ◽

Lower Corona ◽

Diagnostic Capabilities

The paper discusses the diagnostics of plasma jets in the solar corona with the use of data from modern space- and ground-based telescopes observing the Sun in the extreme ultraviolet (EUV) and micro- wave bands. We examine observational parameters of EUV and radio emission in events associated with plasma jets, depending on the mechanism of formation, initiation conditions, and evolution of the jets. The opportunities provided by the study of plasma jets, which relies on simultaneous observations in different bands, are highlighted. For a number of jets, we have measured their primary parameters; and in this paper we present preliminary results of statistical processing of the data obtained. Microwave observations of several specific events, made by ground-based instruments RATAN-600, SRH, and Nobeyama Radioheliograph, are considered in detail. The diagnostic capabilities of these instruments for studying coronal jets are shown. To analyze the three-dimensional structure of the coronal magnetic field, we have used SDO/HMI data, which allowed for the reconstruction of the field in the lower corona. The information gained is compared with the results of diagnostics of the magnetic field at the base of the corona according to RATAN-600 data. The purpose of the methods developed is to determine the physical mechanisms responsible for the generation, collimation, and dynamics of plasma jets in the solar atmosphere.

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Sympathetic Filament Eruptions within a Fan-spine Magnetic System

The Astrophysical Journal ◽

10.3847/1538-4357/ac28a0 ◽

2021 ◽

Vol 923 (1) ◽

pp. 45

Author(s):

Chengrui Zhou ◽

Yuandeng Shen ◽

Xinping Zhou ◽

Zehao Tang ◽

Yadan Duan ◽

...

Keyword(s):

Magnetic Field ◽

Large Scale ◽

Magnetic System ◽

Three Dimensional ◽

Coronal Magnetic Field ◽

Time Interval ◽

Short Time Interval ◽

Flare Loop ◽

Filament Eruption ◽

Large Filament

Abstract It is unclear whether successive filament eruptions at different sites within a short time interval are physically connected or not. Here, we present the observations of successive eruptions of a small and a large filament in a tripolar magnetic field region whose coronal magnetic field showed as a fan-spine magnetic system. By analyzing the multiwavelength observations taken by the Solar Dynamic Observatory and the extrapolated three-dimensional coronal magnetic field, we find that the two filaments resided respectively in the two lobes that make up the inner fan structure of the fan-spine magnetic system. In addition, a small fan-spine system was also revealed by the squashing factor Q map, which located in the east lobe of the fan structure of the large fan-spine system. The eruption of the small filament was a failed filament eruption, which did not cause any coronal mass ejection (CME) except for three flare ribbons and two post-flare-loop systems connecting the three magnetic polarities. The eruption of the large filament not only caused similar post-flare-loop systems and flare ribbons, as observed in the small filament eruption, but also a large-scale CME. Based on our analysis results, we conclude that the two successive filament eruptions were physically connected, in which the topology change caused by the small filament eruption is thought to be the physical linkage. In addition, the eruption of the small fan-spine structure further accelerated the instability and violent eruption of the large filament.

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Diagnostics of plasma jets in the solar corona

Solar-Terrestrial Physics ◽

10.12737/stp-72202101 ◽

2021 ◽

Vol 7 (2) ◽

pp. 3-10

Author(s):

Sergey Anfinogentov ◽

Tatyana Kaltman ◽

Alexey Stupishin ◽

Valery Nakariakov ◽

Maria Lukitcheva

Keyword(s):

Magnetic Field ◽

Solar Corona ◽

Extreme Ultraviolet ◽

Three Dimensional ◽

Statistical Processing ◽

Coronal Magnetic Field ◽

Plasma Jets ◽

Dimensional Structure ◽

Lower Corona ◽

Diagnostic Capabilities

The paper discusses the diagnostics of plasma jets in the solar corona with the use of data from modern space- and ground-based telescopes observing the Sun in the extreme ultraviolet (EUV) and micro- wave bands. We examine observational parameters of EUV and radio emission in events associated with plasma jets, depending on the mechanism of formation, initiation conditions, and evolution of the jets. The opportunities provided by the study of plasma jets, which relies on simultaneous observations in different bands, are highlighted. For a number of jets, we have measured their primary parameters; and in this paper we present preliminary results of statistical processing of the data obtained. Microwave observations of several specific events, made by ground-based instruments RATAN-600, SRH, and Nobeyama Radioheliograph, are considered in detail. The diagnostic capabilities of these instruments for studying coronal jets are shown. To analyze the three-dimensional structure of the coronal magnetic field, we have used SDO/HMI data, which allowed for the reconstruction of the field in the lower corona. The information gained is compared with the results of diagnostics of the magnetic field at the base of the corona according to RATAN-600 data. The purpose of the methods developed is to determine the physical mechanisms responsible for the generation, collimation, and dynamics of plasma jets in the solar atmosphere.

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An elliptic expansion of the potential field source surface model

Astronomy and Astrophysics ◽

10.1051/0004-6361/202037734 ◽

2020 ◽

Vol 638 ◽

pp. A109

Author(s):

M. Kruse ◽

V. Heidrich-Meisner ◽

R. F. Wimmer-Schweingruber ◽

M. Hauptmann

Keyword(s):

Magnetic Field ◽

Potential Field ◽

Three Dimensional ◽

Coronal Magnetic Field ◽

Magnetic Configuration ◽

Surface Model ◽

Source Surface ◽

Field Source ◽

Numerical Solver ◽

Elliptical Models

Context. The potential field source surface model is frequently used as a basis for further scientific investigations where a comprehensive coronal magnetic field is of importance. Its parameters, especially the position and shape of the source surface, are crucial for the interpretation of the state of the interplanetary medium. Improvements have been suggested that introduce one or more additional free parameters to the model, for example, the current sheet source surface model. Aims. Relaxing the spherical constraint of the source surface and allowing it to be elliptical gives modelers the option of deforming it to more accurately match the physical environment of the specific period or location to be analyzed. Methods. A numerical solver is presented that solves Laplace’s equation on a three-dimensional grid using finite differences. The solver is capable of working on structured spherical grids that can be deformed to create elliptical source surfaces. Results. The configurations of the coronal magnetic field are presented using this new solver. Three-dimensional renderings are complemented by Carrington-like synoptic maps of the magnetic configuration at different heights in the solar corona. Differences in the magnetic configuration computed by the spherical and elliptical models are illustrated.

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