STUDY OF THE THREE-DIMENSIONAL CORONAL MAGNETIC FIELD OF ACTIVE REGION 11117 AROUND THE TIME OF A CONFINED FLARE USING A DATA-DRIVEN CESE-MHD MODEL

Characterizing the detailed structure of the magnetic field in the active corona is of crucial importance for determining the chain of events from the formation to the destabilisation and subsequent eruption and propagation of coronal structures in the heliosphere. A comprehensive methodology to address these dynamic processes is needed in order to advance our capabilities to predict the properties of coronal mass ejections (CMEs) in interplanetary space and thereby for increasing the accuracy of space weather predictions. A promising toolset to provide the key missing information on the magnetic structure of CMEs are time-dependent data-driven simulations of active region magnetic fields. This methodology permits self-consistent modeling of the evolution of the coronal magnetic field from the emergence of flux to the birth of the eruption and beyond.&#160;In this presentation, we discuss our modeling efforts in which time-dependent data-driven coronal modeling together with heliospheric physics-based modeling are employed to study and characterize CMEs, in particular their magnetic structure, at various stages in their evolution from the Sun to Earth.&#160;

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Data-driven model of the solar corona above an active region

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935385 ◽

2019 ◽

Vol 624 ◽

pp. L12 ◽

Cited By ~ 4

Author(s):

J. Warnecke ◽

H. Peter

Keyword(s):

Magnetic Field ◽

Active Region ◽

Extreme Ultraviolet ◽

Three Dimensional ◽

Data Driven ◽

Diffuse Emission ◽

Qualitative Level ◽

Induction Equation ◽

Hot Corona ◽

The Magnetic Field

Aims. We aim to reproduce the structure of the corona above a solar active region as seen in the extreme ultraviolet (EUV) using a three-dimensional magnetohydrodynamic (3D MHD) model. Methods. The 3D MHD data-driven model solves the induction equation and the mass, momentum, and energy balance. To drive the system, we feed the observed evolution of the magnetic field in the photosphere of the active region AR 12139 into the bottom boundary. This creates a hot corona above the cool photosphere in a self-consistent way. We synthesize the coronal EUV emission from the densities and temperatures in the model and compare this to the actual coronal observations. Results. We are able to reproduce the overall appearance and key features of the corona in this active region on a qualitative level. The model shows long loops, fan loops, compact loops, and diffuse emission forming at the same locations and at similar times as in the observation. Furthermore, the low-intensity contrast of the model loops in EUV matches the observations. Conclusions. In our model the energy input into the corona is similar as in the scenarios of fieldline-braiding or flux-tube tectonics, that is, energy is transported to the corona through the driving of the vertical magnetic field by horizontal photospheric motions. The success of our model shows the central role that this process plays for the structure, dynamics, and heating of the corona.

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Effects of optimisation parameters on data-driven magnetofrictional modelling

10.5194/egusphere-egu21-9500 ◽

2021 ◽

Author(s):

Anshu Kumari ◽

Daniel Price ◽

Emilia Kilpua ◽

Jens Pomoell ◽

Farhad Daei

Keyword(s):

Magnetic Field ◽

Active Region ◽

Large Scale ◽

Magnetic Energy ◽

Flux Rope ◽

Coronal Magnetic Field ◽

Early Evolution ◽

Data Driven ◽

Magnetic Field Magnitude ◽

Mass Ejection

The solar coronal magnetic field plays an important role in the formation, evolution, and dynamics of small and large-scale structures in the corona. Estimation of the coronal magnetic field, the ultimate driver of space weather, particularly in the &#8216;low&#8217; and &#8216;middle&#8217; corona, is presently limited due to practical difficulties. Data-driven time-dependent magnetofrictional modelling (TMFM) of active region magnetic fields has been proven as a tool to observe and study the corona. In this work, we present a detailed study of data-driven TMFM of active region 12473 to trace the early evolution of the flux rope related to the coronal mass ejection that occurred on 28 December 2015. Non-inductive electric field component in the photosphere is critical for energizing and introducing twist to the coronal magnetic field, thereby allowing unstable configurations to be formed. We estimate this component using an approach based on optimizing the injection of magnetic energy. We study the effects of these optimisation parameters on the data driven coronal simulations. By varying the free optimisation parameters, we explore the changes in flux rope formation and their early evolution, as well other parameters, e.g. axial flux, magnetic field magnitude.

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Analyses of magnetic field structures for active region 10720 using a data-driven 3D MHD model

Advances in Space Research ◽

10.1016/j.asr.2009.03.020 ◽

2009 ◽

Vol 44 (1) ◽

pp. 46-53 ◽

Cited By ~ 15

Author(s):

S.T. Wu ◽

A.H. Wang ◽

G. Allen Gary ◽

Ales Kucera ◽

Jan Rybak ◽

...

Keyword(s):

Magnetic Field ◽

Active Region ◽

Data Driven ◽

Mhd Model

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

First Ten Years of Hinode Solar On-Orbit Observatory - Astrophysics and Space Science Library ◽

10.1007/978-981-10-7742-5_11 ◽

2018 ◽

pp. 115-124

Author(s):

Satoshi Inoue

Keyword(s):

Magnetic Field ◽

Three Dimensional ◽

Coronal Magnetic Field ◽

Photospheric Magnetic Field

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Investigation of the Middle Corona with SWAP and a Data-Driven Non-Potential Coronal Magnetic Field Model

Solar Physics ◽

10.1007/s11207-020-01668-2 ◽

2020 ◽

Vol 295 (7) ◽

Author(s):

Karen A. Meyer ◽

Duncan H. Mackay ◽

Dana-Camelia Talpeanu ◽

Lisa A. Upton ◽

Matthew J. West

Keyword(s):

Magnetic Field ◽

Field Model ◽

Coronal Magnetic Field ◽

Data Driven ◽

Magnetic Field Model

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Data-driven Modeling of the Solar Corona by a New Three-dimensional Path-conservative Osher–Solomon MHD Model

The Astrophysical Journal Supplement Series ◽

10.3847/1538-4365/aa957a ◽

2017 ◽

Vol 233 (1) ◽

pp. 10 ◽

Cited By ~ 8

Author(s):

Xueshang Feng ◽

Caixia Li ◽

Changqing Xiang ◽

Man Zhang ◽

HuiChao Li ◽

...

Keyword(s):

Solar Corona ◽

Three Dimensional ◽

Data Driven ◽

Mhd Model ◽

Data Driven Modeling

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An integrated data-driven solar wind - CME numerical framework for space weather forecasting

Journal of Space Weather and Space Climate ◽

10.1051/swsc/2020068 ◽

2020 ◽

Author(s):

Nishant M. Narechania ◽

Ljubomir Nikolic ◽

Lucie Freret ◽

Hans De Sterck ◽

Clinton P. T. Groth

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Space Weather ◽

Weather Forecasting ◽

Coronal Magnetic Field ◽

Data Driven ◽

Source Surface ◽

Field Source ◽

Space Weather Forecasting ◽

Semi Empirical

The development of numerical models and tools which have operational space weather potential is an increasingly important area of research. This study presents recent Canadian efforts toward the development of a numerical framework for Sun-to-Earth simulations of solar wind disturbances. This modular three-dimensional (3D) simulation framework is based on a semi-empirical data-driven approach to describe the solar corona and an MHD-based description of the heliosphere. In the present configuration, the semi-empirical component uses the Potential Field Source Surface (PFSS) and Schatten Current Sheet (SCS) models to derive the coronal magnetic field based on observed magnetogram data. Using empirical relations, solar wind properties are associated with this coronal magnetic field. Together with a Coronal Mass Ejection (CME) model, this provides inner boundary conditions for a global MHD model which is used to describe interplanetary propagation of the solar wind and CMEs. The proposed MHD numerical approach makes use of advanced numerical techniques. The 3D MHD code employs a finite-volume discretization procedure with limited piecewise linear reconstruction to solve the governing partial-differential equations. The equations are solved on a body-fitted hexahedral multi-block cubed-sphere mesh and an efficient iterative Newton method is used for time-invariant simulations and an explicit time-marching scheme is applied for unsteady cases. Additionally, an efficient anisotropic block-based refinement technique provides significant reductions in the size of the computational mesh by locally refining the grid in selected directions as dictated by the flow physics. The capabilities of the framework for accurately capturing solar wind structures and forecasting solar wind properties at Earth are demonstrated. Furthermore, a comparison with previously reported results and future space weather forecasting challenges are discussed.

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Microwave indicator of potential geoeffectiveness and magnetic flux-rope structure of a solar active region

Solnechno-Zemnaya Fizika ◽

10.12737/szf-71202101 ◽

2021 ◽

Vol 7 (1) ◽

pp. 3-12

Author(s):

Anastasiia Kudriavtseva ◽

Ivan Myshyakov ◽

Arkadiy Uralov ◽

Victor Grechnev

Keyword(s):

Magnetic Field ◽

Active Region ◽

Magnetic Flux ◽

Neutral Line ◽

Flux Rope ◽

Coronal Magnetic Field ◽

Horizontal Magnetic Field ◽

Magnetic Flux Rope ◽

Magnetic Flux Ropes ◽

Class Flare

We analyze the presence of a microwave neutral-line-associated source (NLS) in a super-active region NOAA 12673, which produced a number of geo-effective events in September 2017. To estimate the NLS position, we use data from the Siberian Radioheliograph in a range 4–8 GHz and from the Nobeyama Radioheliograph at 17 GHz. Calculation of the coronal magnetic field in a non-linear force-free approximation has revealed an extended structure consisting of interconnected magnetic flux ropes, located practically along the entire length of the main polarity separation line of the photospheric magnetic field. NLS is projected into the region of the strongest horizontal magnetic field, where the main energy of this structure is concentrated. During each X-class flare, the active region lost magnetic helicity and became a CME source.

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Study of magnetic field topology of active region 12192 using an extrapolated non-force-free magnetic field

Proceedings of the International Astronomical Union ◽

10.1017/s1743921318001151 ◽

2018 ◽

Vol 13 (S340) ◽

pp. 81-82

Author(s):

A. Prasad ◽

R. Bhattacharyya ◽

Q. Hu ◽

S. S. Nayak ◽

Sanjay Kumar

Keyword(s):

Magnetic Field ◽

Active Region ◽

Free Field ◽

Coronal Magnetic Field ◽

Solar Photosphere ◽

Magnetic Field Topology ◽

Cycle 24 ◽

Magnetic Null ◽

The Magnetic Field ◽

Force Free Field

AbstractThe solar active region (AR) 12192 was one of the most flare productive region of solar cycle 24, which produced many X-class flares; the most energetic being an X3.1 flare on October 24, 2014 at 21:10 UT. Customarily, such events are believed to be triggered by magnetic reconnection in coronal magnetic fields. Here we use the vector magnetograms from solar photosphere, obtained from Heliospheric Magnetic Imager (HMI) to investigate the magnetic field topology prior to the X3.1 event, and ascertain the conditions that might have caused the flare. To infer the coronal magnetic field, a novel non-force-free field (NFFF) extrapolation technique of the photospheric field is used, which suitably mimics the Lorentz forces present in the photospheric plasma. We also highlight the presence of magnetic null points and quasi-separatrix layers (QSLs) in the magnetic field topology, which are preferred sites for magnetic reconnections and discuss the probable reconnection scenarios.

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