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Related papers: Coronal heating in multiple magnetic threads

200 papers

The high densities, long lifetimes, and narrow emission measure distributions observed in coronal loops with apex temperatures near 1 MK are difficult to reconcile with physical models of the solar atmosphere. It has been proposed that the…

Solar and Stellar Astrophysics · Physics 2010-04-08 Harry P. Warren , David M. Kim , Amanda M. DeGiorgi , Ignacio Ugarte-Urra

Using full three-dimensional magnetohydrodynamic numerical simulations, we study the effects of magnetic field sigmoidity or helicity on the properties of the fundamental kink oscillation of solar coronal loops. Our model consists of a…

Solar and Stellar Astrophysics · Physics 2020-05-20 N. Magyar , V. M. Nakariakov

In this paper we further develop a model for the heating of coronal loops by Alfven wave turbulence (AWT). The Alfven waves are assumed to be launched from a collection of kilogauss flux tubes in the photosphere at the two ends of the loop.…

Solar and Stellar Astrophysics · Physics 2017-11-08 Adriaan A. van Ballegooijen , Mahboubeh Asgari-Targhi , Alexander Voss

We study the modes and stability of non - isothermal coronal loop models with different intensity values of the equilibrium magnetic field. We use an energy principle obtained via non - equilibrium thermodynamic arguments. The principle is…

Astrophysics · Physics 2008-11-26 Andrea Costa , Rafael Gonzalez

The recent realization that Sweet-Parker current sheets are violently unstable to the secondary tearing (plasmoid) instability implies that such current sheets cannot occur in real systems. This suggests that, in order to understand the…

Solar and Stellar Astrophysics · Physics 2016-03-23 Dmitri A. Uzdensky , Nuno F. Loureiro

The hot solar corona exists because of the balance between radiative and conductive cooling and some counteracting heating mechanism which remains one of the major puzzles in solar physics. The coronal thermal equilibrium is perturbed by…

Solar and Stellar Astrophysics · Physics 2020-11-25 D. Y. Kolotkov , T. J. Duckenfield , V. M. Nakariakov

We investigate the evolution of coronal loop emission in the context of the coronal magnetic field topology. New modeling techniques allow us to investigate the magnetic field structure and energy release in active regions. Using these…

Solar and Stellar Astrophysics · Physics 2015-05-19 J. -Y. Lee , Graham Barnes , K. D. Leka , Katharine K. Reeves , K. E. Korreck , L. Golub , E. E. DeLuca

We have investigated the relaxation of a hydrostatic hot plasma column containing toroidal magnetic field by the Current-Driven (CD) kink instability as a model of pulsar wind nebulae. In our simulations the CD kink instability is excited…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Yosuke Mizuno , Yuri Lyubarsky , Ken-Ichi Nishikawa , Philip E. Hardee

Kinetic Riemann simulations have been completed to explore particle heating during guide field reconnection in the low-$\beta$ environment of the inner heliosphere and the solar corona. The reconnection exhaust is bounded by two rotational…

Plasma Physics · Physics 2019-09-04 Qile Zhang , J. F. Drake , M. Swisdak

This work analyzes the Hall magnetohydrodynamics (HMHD) and magnetohydrodynamics (MHD) numerical simulations of a flaring solar active region as a testbed while idealizing the coronal Alfv\'en speed to be of two orders of magnitude lesser.…

Solar and Stellar Astrophysics · Physics 2022-02-16 Kamlesh Bora , Ramit Bhattacharyya , Avijeet Prasad , Bhuwan Joshi , Qiang Hu

In the context of the solar atmosphere, we re-examine the role of of neutral and ionized species in dissipating the ordered energy of intermediate-mode MHD waves into heat. We solve conservation equations for the hydrodynamics and for…

Solar and Stellar Astrophysics · Physics 2020-09-09 Philip G. Judge

Prominences show a surprising amount of fine structure and it is widely believed that their threads, as seen in H$\alpha$ observations, provide indirect information concerning magnetic field topology. We investigate the spontaneous…

Solar and Stellar Astrophysics · Physics 2020-04-29 Niels Claes , Rony Keppens , Chun Xia

A simplified non-linear numerical model for the development of incompressible magnetohydrodynamics (MHD) in the presence of a strong magnetic field B0 and stratification, nicknamed Shell-Atm, is presented. In planes orthogonal to the mean…

Astrophysics · Physics 2011-02-11 E. Buchlin , M. Velli

We present two-dimensional resistive magnetohydrodynamic simulations of line-tied asymmetric magnetic reconnection in the context of solar flare and coronal mass ejection current sheets. The reconnection process is made asymmetric along the…

Solar and Stellar Astrophysics · Physics 2015-06-04 N. A. Murphy , M. P. Miralles , C. L. Pope , J. C. Raymond , H. D. Winter , K. K. Reeves , D. B. Seaton , A. A. van Ballegooijen , J. Lin

One of the greatest challenges in solar physics is understanding the heating of the Sun's corona. Most theories for coronal heating postulate that free energy in the form of magnetic twist/stress is injected by the photosphere into the…

Solar and Stellar Astrophysics · Physics 2019-09-25 Kalman J. Knizhnik , Spiro K. Antiochos , James A. Klimchuk , C. Richard DeVore

We present results from 3D magnetohydrodynamic (MHD) simulations of the emergence of a twisted convection zone flux tube into a pre-existing coronal dipole field. As in previous simulations, following the partial emergence of the…

Solar and Stellar Astrophysics · Physics 2015-06-18 J. E. Leake , M. G. Linton , S. K. Antiochos

Slow magnetosonic waves associated with flares were observed in coronal loops by SOHO/SUMER, SDO/AIA in various EUV bandpasses, and other instruments. The excitation and damping of slow magnetosonic waves provides information on the…

Solar and Stellar Astrophysics · Physics 2022-02-23 Leon Ofman , Tongjiang Wang

Long-lasting, intense, stellar X-ray flares may approach conditions of breaking magnetic confinement and evolving in open space. We explore this hypothesis with hydrodynamic simulations of flares occurring in a non-confined corona: model…

Astrophysics · Physics 2009-11-07 F. Reale , F. Bocchino , G. Peres

Magnetic reconnection in the quiet Sun is a phenomenon that is consistently observed, and it has recently become feasible to simulate via 3D numerical models of realistically stratified and convection-driven reconnection. We aim to…

Solar and Stellar Astrophysics · Physics 2022-12-21 Rebecca Robinson , Mats Carlsson , Guillaume Aulanier

Coronal heating refers to the physical processes that shape and structure the corona of the Sun and are responsible for its multi-million Kelvin temperatures. These processes are revealed in a number of different observational…

Solar and Stellar Astrophysics · Physics 2024-09-23 Iñigo Arregui , Tom Van Doorsselaere