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Related papers: Investigating 4D Coronal Heating Events In MHD Sim…

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Advanced 3D radiative MHD simulations now reproduce many properties of the outer solar atmosphere. When including a domain from the convection zone into the corona, a hot chromosphere and corona are self-consistently maintained. Here we…

Solar and Stellar Astrophysics · Physics 2015-10-07 Viggo Hansteen , Nuno Guerreiro , Bart De Pontieu , Mats Carlsson

Even in the absence of resolved flares, the corona is heated to several million degrees. However, despite its importance for the structure, dynamics, and evolution of the solar atmosphere, the origin of this heating remains poorly…

We investigate the thermal, kinematic and magnetic structure of small-scale heating events in an emerging flux region (EFR). We use high-resolution multi-line observations (including Ca II 8542~\AA, Ca II K, and Fe I 6301~\AA line pair) of…

Solar and Stellar Astrophysics · Physics 2023-09-14 Rahul Yadav , Maria D. Kazachenko , Andrey N. Afanasyev , Jaime de la Cruz Rodríguez , Jorrit Leenaarts

The existence of the million-degree corona above the cooler photosphere is an unsolved problem in astrophysics. Detailed study of quiescent corona that exists regardless of the phase of the solar cycle may provide fruitful hints towards…

Solar and Stellar Astrophysics · Physics 2022-12-07 Vishal Upendran , Durgesh Tripathi , N. P. S. Mithun , Santosh Vadawale , Anil Bhardwaj

Small-scale magnetic reconnection processes, in the form of nanoflares, have become increasingly hypothesized as important mechanisms for the heating of the solar atmosphere, for driving propagating disturbances along magnetic field lines…

Transition region explosive events are characterized by non-Gaussian profiles of the emission lines formed at transition region temperatures, and they are believed to be manifestations of small-scale reconnection events in the transition…

Solar and Stellar Astrophysics · Physics 2024-12-25 Yajie Chen , Hardi Peter , Damien Przybylski

The solar corona is much hotter than the photosphere and chromosphere, but the physical mechanism responsible for heating the coronal plasma remains unidentified yet. The thermal microwave emission, which is produced in strong magnetic…

Solar and Stellar Astrophysics · Physics 2025-08-27 Alexey A. Kuznetsov , Gregory D. Fleishman , Gelu M. Nita , Sergey A. Anfinogentov

We present the first results of three-dimensional (3D) numerical magnetohydrodynamic (MHD) simulations of the onset of magnetic reconnection via the tearing instability in dynamically thinning current sheets in the solar corona. In all our…

Solar and Stellar Astrophysics · Physics 2024-06-10 James Leake , Lars Daldorff , James Klimchuk

We highlight ten key aspects of coronal heating that must be understood before we can consider the problem to be solved. (1) All coronal heating is impulsive. (2) The details of coronal heating matter. (3) The corona is filled with…

Solar and Stellar Astrophysics · Physics 2015-04-13 James A. Klimchuk

Reconnection-driven nanoflares are widely considered a leading mechanism for coronal-loop heating, but their direct fingerprints in the tenuous coronal plasma remain elusive. The recently discovered coronal nanojets offer a potential probe…

Observations suggest a power-law relation between the coronal emission in X-rays, $L_{\rm{X}}$, and the total (unsigned) magnetic flux at the stellar surface, $\Phi$. The physics basis for this relation is poorly understood. We use…

Solar and Stellar Astrophysics · Physics 2021-08-04 J. Zhuleku , J. Warnecke , H. Peter

The content of hot material in the corona is not constant. Soft X-ray and high-temperature EUV line observations show that new material, apparently heated and evaporated from the chromosphere, is frequently injected into the corona both in…

Astrophysics · Physics 2016-08-30 Arnold O. Benz , Paolo C. Grigis

Microflares, one of small-scale solar activities, are believed to be caused by magnetic reconnection. Nevertheless, their three-dimensional (3D) magnetic structures, thermodynamic structures, and physical links to the reconnection have been…

Solar and Stellar Astrophysics · Physics 2022-05-18 Z. F. Li , X. Cheng , F. Chen , J. Chen , M. D. Ding

The energy input into the lower solar corona by flare evaporation events has been modeled according to the available observations for quiet regions. The question is addressed whether such heating events can provide the observed average…

Astrophysics · Physics 2008-11-26 U. Mitra-Kraev , A. O. Benz

Magnetic reconnection, a fundamentally important process in many aspects of astrophysics, is believed to be initiated by the tearing instability of an electric current sheet, a region where magnetic field abruptly changes direction and…

Solar and Stellar Astrophysics · Physics 2020-03-11 James Leake , Lars Daldorff , James Klimchuk

Nanoflare heating through small-scale magnetic reconnection events is one of the prime candidates to explain heating of the solar corona. However, direct signatures of nanoflares are difficult to determine, and unambiguous observational…

Solar and Stellar Astrophysics · Physics 2023-07-12 H. Bakke , L. Frogner , L. Rouppe van der Voort , B. V. Gudiksen , M. Carlsson

Context: It is thought likely that vast numbers of nanoflares are responsible for the corona having a temperature of millions of degrees. Current observational technologies lack the resolving power to confirm the nanoflare hypothesis. An…

Solar and Stellar Astrophysics · Physics 2015-05-19 Michael R. Bareford , Philippa. K. Browning , Ronald A. M. Van der Linden

The energy that heats the magnetically closed solar corona originates in the complex motions of the massive photosphere. Turbulent photospheric convection slowly displaces the footpoints of coronal field lines, causing them to become…

The evolution of a coronal loop is studied by means of numerical simulations of the fully compressible three-dimensional magnetohydrodynamic equations using the HYPERION code. The footpoints of the loop magnetic field are advected by random…

Solar and Stellar Astrophysics · Physics 2016-01-22 R. B. Dahlburg , G. Einaudi , B. D. Taylor , I. Ugarte-Urra , H. P. Warren , A. F. Rappazzo , M. Velli

The transport of waves and turbulence beyond the photosphere is central to the coronal heating problem. Turbulence in the quiet solar corona has been modeled on the basis of the nearly incompressible magnetohydrodynamic (NI MHD) theory to…

Solar and Stellar Astrophysics · Physics 2023-01-12 Mehmet Sarp Yalim , Gary P. Zank , Mahboubeh Asgari-Targhi