Flare Energy Release at the Magnetic Field Polarity Inversion Line during the M1.2 Solar Flare of 2015 March 15. I. Onset of Plasma Heating and Electron Acceleration

Primordial release of solar flare energy high in corona (at altitudes 1/40 - 1/20 of the solar radius) is explained by release of the magnetic energy of the current sheet. The observed manifestations of the flare are explained by the electrodynamical model of a solar flare proposed by I. M. Podgorny. To study the flare mechanism is necessary to perform MHD simulations above a real active region (AR). MHD simulation in the solar corona in the real scale of time can only be carried out thanks to parallel calculations using CUDA technology. Methods have been developed for stabilizing numerical instabilities that arise near the boundary of the computational domain. Methods are applicable for low viscosities in the main part of the domain, for which the flare energy is effectively accumulated near the singularities of the magnetic field. Singular lines of the magnetic field, near which the field can have a rather complex configuration, coincide or are located near the observed positions of the flare.

Download Full-text

New data-driven method of simulating coronal mass ejections

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935225 ◽

2019 ◽

Vol 626 ◽

pp. A91 ◽

Cited By ~ 1

Author(s):

Cheng’ao Liu ◽

Tao Chen ◽

Xinhua Zhao

Keyword(s):

Magnetic Field ◽

Coronal Mass Ejections ◽

Three Dimensional ◽

Flux Rope ◽

Mhd Equations ◽

Data Driven ◽

Flux Emergence ◽

Polarity Inversion ◽

Polarity Inversion Line ◽

The Magnetic Field

Context. Coronal mass ejections (CMEs) are large eruptions of plasma and magnetic field from the Sun’s corona. Understanding the evolution of the CME is important to evaluate its impact on space weather. Using numerical simulation, we are able to reproduce the occurrence and evolution process of the CME. Aims. The aim of this paper is to provide a new data-driven method to mimic the coronal mass ejections. By using this method, we can investigate the phsical mechanisms of the flux rope formation and the cause of the CME eruption near the real background. Methods. Starting from a potential magnetic field extrapolation, we have solved a full set of magnetohydrodynamic (MHD) equations by using the conservation element and solution element (CESE) numerical method. The bottom boundary is driven by the vector magnetograms obtained from SDO/HMI and vector velocity maps derived from DAVE4VM method. Results. We present a three-dimensional numerical MHD data-driven model for the simulation of the CME that occurred on 2015 June 22 in the active region NOAA 12371. The numerical results show two elbow-shaped loops formed above the polarity inversion line (PIL), which is similar to the tether-cutting picture previously proposed. The temporal evolutions of magnetic flux show that the sunspots underwent cancellation and flux emergence. The signature of velocity field derived from the tracked magnetograms indicates the persistent shear and converging motions along the PIL. The simulation shows that two elbow-shaped loops were reconnected and formed an inverse S-shaped sigmoid, suggesting the occurrence of the tether-cutting reconnection, which was supported by observations of the Atmospheric Imaging Assembly (AIA) telescope. Analysis of the decline rate of the magnetic field indicates that the flux rope reached a region where the torus instability was triggered. Conclusions. We conclude that the eruption of this CME was caused by multiple factors, such as photosphere motions, reconnection, and torus instability. Moreover, our simulation successfully reproduced the three-component structures of typical CMEs.

Download Full-text

Rapid Disappearance of Penumbra-Like Features near a Flaring Polarity Inversion Line: The Hinode Observations

Advances in Astronomy ◽

10.1155/2012/735879 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

B. Ravindra ◽

Sanjay Gosain

Keyword(s):

Magnetic Field ◽

Vertical Component ◽

Vector Magnetic Field ◽

Polarity Inversion ◽

X Ray ◽

Horizontal Flows ◽

Before And After ◽

Polarity Inversion Line ◽

The Magnetic Field ◽

Class Flare

We present the observations of penumbra-like features (PLFs) near a polarity inversion line (PIL) of flaring region. The PIL is located at the moat boundary of active region (NOAA 10960). The PLFs appear similar to sunspot penumbrae in morphology but occupy small area, about6×107 km2, and are not associated with sunspot or pore. We observed a rapid disappearance of the PLFs after a C1.7 class flare, which occurred close to the PIL. The local correlation tracking (LCT) of these features shows presence of horizontal flows directed away from the end-points of the PLFs, similar to the radial outward flow found around regular sunspots, which is also known as the moat flow. Hard X-ray emission, coincident with the location of the PLFs, is found in RHESSI observations, suggesting a spatial correlation between the occurrence of the flare and decay of the PLFs. Vector magnetic field derived from the observations obtained by Hinode spectropolarimeter SOT/SP instrument, before and after the flare, shows a significant change in the horizontal as well as the vertical component of the field, after the flare. The weakening of both the components of the magnetic field in the flare interval suggests that rapid cancellation and/or submergence of the magnetic field in PLFs occurred during the flare interval.

Download Full-text

Improved and Interpretable Solar Flare Predictions with Spatial & Topological Features of the Polarity-Inversion-Line Masked Magnetograms

10.1002/essoar.10507540.1 ◽

2021 ◽

Author(s):

Hu Sun ◽

Ward Beecher Manchester IV ◽

Yang Chen

Keyword(s):

Solar Flare ◽

Polarity Inversion ◽

Topological Features ◽

Polarity Inversion Line

Download Full-text

Regions of primary energy release of solar flares associated with singularities in the magnetic field

Astronomy Reports ◽

10.1134/s1063772910050094 ◽

2010 ◽

Vol 54 (5) ◽

pp. 456-464 ◽

Cited By ~ 2

Author(s):

O. G. Den ◽

I. V. Zimovets

Keyword(s):

Magnetic Field ◽

Energy Release ◽

Solar Flares ◽

Primary Energy ◽

The Magnetic Field

Download Full-text

An Energy Storage Mechanism for a Solar Flare by Shearing the Magnetic Field

Highlights of Astronomy ◽

10.1007/978-94-010-9376-7_117 ◽

1986 ◽

pp. 767-768

Author(s):

Xinping Liu

Keyword(s):

Magnetic Field ◽

Energy Storage ◽

Solar Flare ◽

Storage Mechanism ◽

The Magnetic Field

Download Full-text

The Tearing Mode Instability in a Partially Ionized Plasma

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000026114 ◽

1979 ◽

Vol 3 (6) ◽

pp. 367-368 ◽

Cited By ~ 3

Author(s):

N. F. Cramer ◽

I. J. Donnelly

Keyword(s):

Magnetic Field ◽

Star Formation ◽

Solar Flare ◽

Experimental Evidence ◽

Energy Release ◽

Release Mechanism ◽

Tearing Mode ◽

Mode Instability ◽

Laboratory Plasma ◽

Tearing Instability

The resistive tearing mode instability is a mechanism that in some cases will render unstable a magnetohydrodynamic equilibrium of a plasma that is ideally stable, i.e. stable if no dissipative oiesses are taken into account. There is much experimental evidence that this instability is the cause of the current disruptions observed in laboratory plasma devices (von Goeler et al. 1974). In the astrophysical context, the instability has been invoked in connection with the solar flare energy release mechanism (Coppi and Friedland 1971) and the problem of the disconnection of the protostar matter from the interstellar magnetic field during star formation (Mestel 1966). In the latter problem the tearing instability gives rise to a much smaller timescale for magnetic reconnection than does ordinary resistive diffusion.

Download Full-text

Excitation of kinetic Alfvén turbulence by MHD waves and energization of space plasmas

Nonlinear Processes in Geophysics ◽

10.5194/npg-11-535-2004 ◽

2004 ◽

Vol 11 (5/6) ◽

pp. 535-543 ◽

Cited By ~ 23

Author(s):

Y. Voitenko ◽

M. Goossens

Keyword(s):

Magnetic Field ◽

Large Scale ◽

Energy Transport ◽

Plasma Heating ◽

Alfven Wave ◽

Mhd Waves ◽

Space Plasmas ◽

Small Scale ◽

The Magnetic Field ◽

Dissipation Range

Abstract. There is abundant observational evidence that the energization of plasma particles in space is correlated with an enhanced activity of large-scale MHD waves. Since these waves cannot interact with particles, we need to find ways for these MHD waves to transport energy in the dissipation range formed by small-scale or high-frequency waves, which are able to interact with particles. In this paper we consider the dissipation range formed by the kinetic Alfvén waves (KAWs) which are very short- wavelengths across the magnetic field irrespectively of their frequency. We study a nonlocal nonlinear mechanism for the excitation of KAWs by MHD waves via resonant decay AW(FW)→KAW1+KAW2, where the MHD wave can be either an Alfvén wave (AW), or a fast magneto-acoustic wave (FW). The resonant decay thus provides a non-local energy transport from large scales directly in the dissipation range. The decay is efficient at low amplitudes of the magnetic field in the MHD waves, B/B0~10-2. In turn, KAWs are very efficient in the energy exchange with plasma particles, providing plasma heating and acceleration in a variety of space plasmas. An anisotropic energy deposition in the field-aligned degree of freedom for the electrons, and in the cross-field degrees of freedom for the ions, is typical for KAWs. A few relevant examples are discussed concerning nonlinear excitation of KAWs by the MHD wave flux and consequent plasma energization in the solar corona and terrestrial magnetosphere.

Download Full-text