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Related papers: Magnetohydrodynamics dynamical relaxation of coron…

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Starting from an exact, steady-state, force-free solution of the magnetohydrodynamic (MHD) equations, we investigate how resistive current layers are induced by perturbing line-tied three-dimensional magnetic equilibria. This is achieved by…

Solar and Stellar Astrophysics · Physics 2016-01-12 Frederic Effenberger , I. J. D. Craig

Context: Coronal magnetic null points have been implicated as possible locations for localised heating events in 2D models. We investigate this possibility about fully 3D null points. Aims: We investigate the nature of the fast…

Solar and Stellar Astrophysics · Physics 2012-08-30 J. O. Thurgood , J. A. McLaughlin

We report here, for the first time, an observed instability of a Kelvin-Helmholtz (KH) nature occurring in a fully three-dimensional (3D) current-vortex sheet at the fan plane of a 3D magnetic null point. The current-vortex layer forms…

Solar and Stellar Astrophysics · Physics 2013-04-09 P. F. Wyper , D. I. Pontin

Context: Magnetic null points are associated with high-energy coronal phenomena such as solar flares and are often sites of reconnection and particle acceleration. Dynamic twisting of a magnetic null point can generate a Kelvin-Helmholtz…

Solar and Stellar Astrophysics · Physics 2021-06-23 James Quinn , David MacTaggart , Radostin Simitev

Context: The strong electric fields associated with magnetic reconnection in solar flares are a plausible mechanism to accelerate populations of high energy, non-thermal particles. One such reconnection scenario occurs at a 3D magnetic null…

Solar and Stellar Astrophysics · Physics 2015-06-03 Adam J. Stanier , Philippa K. Browning , Silvia Dalla

Three-dimensional (3D) magnetohydrodynamic simulations are carried out to explore magnetic reconnections in the presence of 3D magnetic nulls and quasi-separatrix layers (QSLs). The initial magnetic fields are created by superposing uniform…

Solar and Stellar Astrophysics · Physics 2021-02-10 Sanjay Kumar , Sushree S. Nayak , Avijeet Prasad , Ramit Bhattacharyya

Many magnetic structures in the solar atmosphere evolve rather slowly so that they can be assumed as (quasi-)static or (quasi-)stationary and represented via magneto-hydrostatic (MHS) or stationary magneto-hydrodynamic (MHD) equilibria,…

Solar and Stellar Astrophysics · Physics 2017-03-15 Dieter H. Nickeler , Thomas Wiegelmann , Marian Karlicky , Michaela Kraus

Three-dimensional magnetic null points are ubiquitous in the solar corona, and in any generic mixed-polarity magnetic field. We consider magnetic reconnection at an isolated coronal null point, whose fan field lines form a dome structure.…

Solar and Stellar Astrophysics · Physics 2013-08-29 D. I. Pontin , E. R. Priest , K. Galsgaard

We study the magnetic field and current structure associated with a coronal loop. Through this we investigate to what extent the assumptions of a force-free magnetic field break down and where they might be justified. We analyse a 3D MHD…

Solar and Stellar Astrophysics · Physics 2017-12-05 Jörn Warnecke , Feng Chen , Sven Bingert , Hardi Peter

Context: MHD waves and magnetic null points are both prevalent in many astrophysical plasmas, including the solar atmosphere. Interaction between waves and null points has been implicated as a possible mechanism for localised heating…

Solar and Stellar Astrophysics · Physics 2015-06-16 J. O. Thurgood , J. A. McLaughlin

Here we detail the dynamic evolution of localised reconnection regions about three-dimensional (3D) magnetic null points by using numerical simulation. We demonstrate for the first time that reconnection triggered by the localised collapse…

Solar and Stellar Astrophysics · Physics 2017-07-26 J. O. Thurgood , D. I. Pontin , J. A. McLaughlin

Coronal rain, observed in 3D spine-fan magnetic configurations, results from thermal instability in the solar corona, where runaway in-situ cooling causes plasma to condense and drain along the magnetic lines. The reconnection of the…

Solar and Stellar Astrophysics · Physics 2025-06-18 Beatrice Popescu Braileanu , Rony Keppens

Coronal heating has been a long-standing conundrum in solar physics. Parker's conjecture that spontaneous current singularities lead to nanoflares that heat the corona has been controversial. In ideal magnetohydrodynamics (MHD), can genuine…

Plasma Physics · Physics 2017-08-30 Yao Zhou

Magnetohydrodynamics of the solar corona is simulated numerically. The simulation is initialized with an extrapolated non-force-free magnetic field using the vector magnetogram of the active region (AR) NOAA 12192 obtained on the solar…

Solar and Stellar Astrophysics · Physics 2018-06-26 A. Prasad , R. Bhattacharyya , Qiang Hu , Sanjay Kumar , Sushree S. Nayak

We study the propagation and dissipation of magnetohydrodynamic waves in a set of numerical models that each include a solar--like stratified atmosphere and a magnetic field with a null point. All simulations have the same magnetic field…

Solar and Stellar Astrophysics · Physics 2019-07-24 Lucas A. Tarr , Mark Linton

We present a numerical study in resistive magnetohydrodynamics where the initial equilibrium configuration contains adjacent, oppositely directed, parallel current channels. Since oppositely directed current channels repel, the equilibrium…

Solar and Stellar Astrophysics · Physics 2015-06-22 Rony Keppens , Oliver Porth , Chun Xia

We present a new MHD wave decomposition method that overcomes the limitations of existing wave identification methods. Our method allows to investigate the energy fluxes in different MHD modes at different locations of the solar atmosphere…

Solar and Stellar Astrophysics · Physics 2022-04-20 N. Yadav , Rony Keppens , B. Popescu Braileanu

This paper is a demonstration of how the WKB approximation can be used to help solve the linearised 3D MHD equations. Using Charpit's Method and a Runge-Kutta numerical scheme, we have demonstrated this technique for a potential 3D magnetic…

Astrophysics · Physics 2009-11-13 J. A. McLaughlin , J. S. L. Ferguson , A. W. Hood

Implosive formation of current sheets is a fundamental plasma process. Previous studies focused on the early time evolution, while here our primary aim is to explore the longer-term evolution, which may be critical for determining the…

Plasma Physics · Physics 2018-07-12 J. O. Thurgood , D. I. Pontin , J. A. McLaughlin

We address the formation of 3D nullpoint topologies in the solar corona by combining Hinode/XRT observations of a small dynamic limb event, which occurred beside a non-erupting prominence cavity, with a 3D zero-beta MHD simulation. To this…

Solar and Stellar Astrophysics · Physics 2014-11-20 T. Toeroek , G. Aulanier , B. Schmieder , K. K. Reeves , L. Golub