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Related papers: Fluctuation dynamo based on magnetic reconnections

200 papers

It is generally believed that the magnetic free energy accumulated in the corona serves as a main energy source for solar explosions such as coronal mass ejections (CMEs). In the framework of the flux rope catastrophe model for CMEs, the…

Astrophysics · Physics 2009-06-23 Y. Chen , Y. Q. Hu , S. J. Sun

Magnetic neutral points, where the magnitude of the magnetic field vanishes locally, are potential locations for energy conversion in the solar corona. The fact that the magnetic field is identically zero at these points suggests that for…

Solar and Stellar Astrophysics · Physics 2012-02-02 Jorge Fuentes-Fernández , Clare E. Parnell , Alan W. Hood , Eric R. Priest , Dana W. Longcope

We demonstrate that a magneto-convection simulation incorporating essential physical processes governing solar surface convection exhibits turbulent small-scale dynamo action. By presenting a derivation of the energy balance equation and…

Solar and Stellar Astrophysics · Physics 2010-04-23 Jonathan Pietarila Graham , Robert Cameron , Manfred Schuessler

Context: Recent satellite measurements in the turbulent magnetosheath of Earth have given evidence of an unusual reconnection mechanism that is driven exclusively by electrons. This newly observed process was called electron-only…

Plasma Physics · Physics 2020-10-07 Giuseppe Arrò , Francesco Califano , Giovanni Lapenta

Intermittent large-scale high-shear flows are found to occur frequently and spontaneously in direct numerical simulations of statistically stationary turbulent Boussinesq magnetohydrodynamic (MHD) convection. The energetic steady-state of…

Solar and Stellar Astrophysics · Physics 2013-09-06 J. Pratt , A. Busse , W. -C. Mueller

During the last few decades, the most widely favored models for coronal heating have involved the in situ dissipation of energy, with footpoint shuffling giving rise to multiple current sheets (the "nanoflare" model) or to Alfv{\'e}n waves…

Solar and Stellar Astrophysics · Physics 2022-10-04 Y. -M. Wang

We analyze particle acceleration in explosive reconnection events in magnetically dominated proton-electron plasmas. Reconnection is driven by large-scale magnetic stresses in interacting current-carrying flux tubes. Our model relies on…

High Energy Astrophysical Phenomena · Physics 2019-02-07 B. Ripperda , O. Porth , C. Xia , R. Keppens

Whether a solar eruption is successful or failed depends on the competition between different components of the Lorentz force exerting on the flux rope that drives the eruption. The present models only consider the strapping force generated…

Solar and Stellar Astrophysics · Physics 2021-05-18 Ze Zhong , Yang Guo , Mingde Ding

Magnetic flux ropes are a bundle of twisted magnetic field lines produced by internal electric currents, which are responsible for solar eruptions and are the major drivers of geomagnetic storms. As such, it is crucial to develop a…

Solar and Stellar Astrophysics · Physics 2023-10-31 J. H. Guo , Y. W. Ni , Y. Guo , C. Xia , B. Schmieder , S. Poedts , Z. Zhong , Y. H. Zhou , F. Yu , P. F. Chen

Combined action of helical motions of plasma (the $\alpha$ effect) and non-uniform (differential) rotation is a key dynamo mechanism of solar and galactic large-scale magnetic fields. Dynamics of magnetic helicity of small-scale fields is a…

Solar and Stellar Astrophysics · Physics 2022-09-20 N. Kleeorin , I. Rogachevskii

In this paper, the magneto-heating coupling model is studied in details, with turbulent convection zone and the flow field involved. Our main work is to analyze the well-posed property of this model with the regularity techniques. For the…

Numerical Analysis · Mathematics 2017-12-07 Changhui Yao , Yanping Lin , Lixiu Wang , Xuefan Jia

The magnetic field plays a crucial role in heating the solar corona, but the exact energy release mechanism(s) is(are) still unknown. Here, we investigate in detail, the process of magnetic energy release in a situation where two initially…

Astrophysics · Physics 2009-11-10 K. Galsgaard , C. E. Parnell

Solar flares can release coronal magnetic energy explosively and may impact the safety of near-earth space environments. Their structures and properties on macroscale have been interpreted successfully by the generally-accepted…

Solar and Stellar Astrophysics · Physics 2023-09-11 Yulei Wang , Xin Cheng , Mingde Ding , Zhaoyuan Liu , Jian Liu , Xiaojue Zhu

A 2.5-dimensional magnetohydrodynamics simulation analysis of the energy release for three different reconnection regimes is presented. The system under investigation consists in a current-sheet located in a medium with a strong density…

Solar and Stellar Astrophysics · Physics 2011-02-24 Lapo Bettarini , Giovanni Lapenta

We present 3D numerical simulations and an analytic model of reflection-driven MHD turbulence in the solar wind. Our simulations describe transverse, non-compressive MHD fluctuations within a narrow magnetic flux tube that extends from the…

Space Physics · Physics 2019-09-04 Benjamin D. G. Chandran , Jean C. Perez

Understanding magnetic-field generation and amplification in turbulent plasma is essential to account for observations of magnetic fields in the universe. A theoretical framework attributing the origin and sustainment of these fields to the…

With the observations of the Solar Dynamics Observatory, we present the slipping magnetic reconnections with multiple flare ribbons (FRs) during an X1.2 eruptive flare on 2014 January 7. A center negative polarity was surrounded by several…

Solar and Stellar Astrophysics · Physics 2016-06-08 Ruisheng Zheng , Yao Chen , Bing Wang

We present simulations modeling closed regions of the solar corona threaded by a strong magnetic field where localized photospheric vortical motions twist the coronal field lines. The linear and nonlinear dynamics are investigated in the…

Solar and Stellar Astrophysics · Physics 2013-06-20 A. F. Rappazzo , M. Velli , G. Einaudi

We investigate which scalar quantity or quantities can best predict the loss of equilibrium and subsequent eruption of magnetic flux ropes in the solar corona. Our models are initialized with a potential magnetic arcade, which is then…

Solar and Stellar Astrophysics · Physics 2023-08-29 Oliver E. K. Rice , Anthony R. Yeates

It has recently been shown that a significant slowdown of many stars can be attributed to the emergence of a strong magnetic field within the radiative region, where heat is transferred through radiation in a stably stratified layer. Here,…

Fluid Dynamics · Physics 2023-11-30 Florentin Daniel , Ludovic Petitdemange , Christophe Gissinger