NUMERICAL EXPERIMENTS ON FINE STRUCTURE WITHIN RECONNECTING CURRENT SHEETS IN SOLAR FLARES

Solar energetic particles are an integral part of the physical processes related with space weather. We present a review for the acceleration mechanisms related to the explosive phenomena (flares and/or coronal mass ejections, CMEs) inside the solar corona. For more than 40 years, the main two-dimensional cartoon representing our understanding of the explosive phenomena inside the solar corona remained almost unchanged. The acceleration mechanisms related to solar flares and CMEs also remained unchanged and were part of the same cartoon. In this review, we revise the standard cartoon and present evidence from recent global magnetohydrodynamic simulations that support the argument that explosive phenomena will lead to the spontaneous formation of current sheets in different parts of the erupting magnetic structure. The evolution of the large-scale current sheets and their fragmentation will lead to strong turbulence and turbulent reconnection during solar flares and turbulent shocks. In other words, the acceleration mechanism in flares and CME-driven shocks may be the same, and their difference will be the overall magnetic topology, the ambient plasma parameters, and the duration of the unstable driver. This article is part of the theme issue ‘Solar eruptions and their space weather impact’.

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Spontaneous formation of electric current sheets and the origin of solar flares

The Astrophysical Journal ◽

10.1086/165918 ◽

1988 ◽

Vol 324 ◽

pp. 574 ◽

Cited By ~ 146

Author(s):

B. C. Low ◽

R. Wolfson

Keyword(s):

Electric Current ◽

Solar Flares ◽

Current Sheets ◽

Spontaneous Formation

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Recent progress made in numerical experiments on magnetic reconnection and the related solar activities

10.5194/egusphere-egu21-16423 ◽

2021 ◽

Author(s):

Jun Lin ◽

Jing Ye

Keyword(s):

Magnetic Reconnection ◽

Solar Flares ◽

Numerical Experiments ◽

Recent Progress ◽

Magnetic Energy ◽

Solar Physics ◽

Plasma Heating ◽

Mhd Turbulence ◽

2D And 3D ◽

Made In

<p>Magnetic reconnection plays a crucial role in the process of solar flares and coronal mass ejections, in which large amounts of magnetic energy (10^29-10^32 ergs) are converted into kinetic energy and thermal energy, even allowing for particle acceleration. On the platform of the Computational Solar Physics Laboratory of Yunnan Observatories, we have performed a series of numerical experiments on magnetic reconnection related to solar eruption events as well as numerical method developments both in 2D and 3D. In this talk, we will present some recent studies on the topic of plasma heating by reconnection, MHD turbulence, wave structures and complicate structures of CMEs, etc. Our numerical results have great potentials to explain and predict many related solar activities in the corona.&#160;</p>

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Investigating the Mechanism of the Acceleration of Cosmic Rays during Solar Flares Using the Electric Field in Current Sheets of the Solar Corona

Bulletin of the Russian Academy of Sciences Physics ◽

10.3103/s1062873821080207 ◽

2021 ◽

Vol 85 (8) ◽

pp. 925-927

Author(s):

A. I. Podgorny ◽

I. M. Podgorny ◽

A. V. Borisenko ◽

E. V. Vashenyuk ◽

Yu. V. Balabin ◽

...

Keyword(s):

Cosmic Rays ◽

Electric Field ◽

Solar Corona ◽

Solar Flares ◽

Current Sheets

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Theories of Small-Scale Magnetic Fields

Symposium - International Astronomical Union ◽

10.1017/s0074180900022932 ◽

1971 ◽

Vol 43 ◽

pp. 457-474 ◽

Cited By ~ 2

Author(s):

P. A. Sweet

Keyword(s):

Fine Structure ◽

Magnetic Fields ◽

Solar Flares ◽

Large Scale ◽

Large Scale Structure ◽

Energetic Particles ◽

Scale Structure ◽

Small Scale ◽

Solar Chromosphere

This review is concerned with the origin of the fine structure of the fields and their relationship to the heating of the solar chromosphere and corona, the structure of prominences and the production of energetic particles in solar flares. The dynamics of sunspot formation, and the large-scale structure of individual sunspots have not been dealt with, although the evolution of AR fields has been considered insofar as it affects the flare problem.

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