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Related papers: Nanoflare Heating: Observations and Theory

200 papers

A full 3-dimensional compressible magnetohydrodynamic (MHD) simulation is conducted to investigate the thermal responses of a coronal loop to the dynamic dissipation processes of MHD waves. When the foot points of the loop are randomly and…

Solar and Stellar Astrophysics · Physics 2018-03-14 Takuma Matsumoto

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

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…

All theories that attempt to explain the heating of the high temperature plasma observed in the solar corona are based on short bursts of energy. The intensities and velocities measured in the cores of quiescent active regions, however, can…

Solar and Stellar Astrophysics · Physics 2015-06-05 Fana M. Mulu-Moore , Amy R. Winebarger , Harry P. Warren

One candidate-model for heating the solar corona is magnetic reconnection that embodies Ohmic dissipation of current sheets. When numerous small-scaled magnetic reconnection occur, then it is possible to heat the corona. Due to the…

Solar and Stellar Astrophysics · Physics 2018-09-19 Charalambos Kanella , Boris V. Gudiksen

It is largely agreed that many coronal loops---those observed at a temperature of about 1 MK--- are bundles of unresolved strands that are heated by storms of impulsive nanoflares. The nature of coronal heating in hotter loops and in the…

Solar and Stellar Astrophysics · Physics 2015-05-28 Nicholeen M. Viall , James A. Klimchuk

We model nanoflare heating of extrapolated active-region coronal loops via the acceleration of electrons and protons in Harris-type current sheets. The kinetic energy of the accelerated particles is estimated using semi-analytical and…

Solar and Stellar Astrophysics · Physics 2015-06-16 C. Gontikakis , S. Patsourakos , C. Efthymiopoulos , A. Anastasiadis , M. K. Georgoulis

Alfven waves created by sub-photospheric motions or by magnetic reconnection in the low solar atmosphere seem good candidates for coronal heating. However, the corona is also likely to be heated more directly by magnetic reconnection, with…

Solar and Stellar Astrophysics · Physics 2015-05-13 P. Antolin , K. Shibata , T. Kudoh , D. Shiota , D. Brooks

The corona is a layer of hot plasma that surrounds the Sun, traces out its complex magnetic field, and ultimately expands into interplanetary space as the supersonic solar wind. Although much has been learned in recent decades from advances…

Solar and Stellar Astrophysics · Physics 2019-09-11 Steven R. Cranmer , Amy R. Winebarger

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

The question why the solar corona is much hotter than the visible solar surface still puzzles solar researchers. Most theories of the coronal heating involve a tight coupling between the coronal magnetic field and the associated thermal…

Solar and Stellar Astrophysics · Physics 2021-03-17 Gregory D. Fleishman , Sergey A. Anfinogentov , Alexey G. Stupishin , Alexey A. Kuznetsov , Gelu M. Nita

We investigate the spatial and temporal evolution of the heating of the corona of a cool star such as our Sun in a three-dimensional magneto-hydrodynamic (3D MHD) model. We solve the 3D MHD problem numerically in a box representing part of…

Space Physics · Physics 2015-05-27 Sven Bingert , Hardi Peter

The properties expected of "hot" non-flaring plasmas due to nanoflare heating in active regions are investigated using hydrodynamic modeling tools, including a two-fluid development of the EBTEL code. Here we study a single nanoflare and…

Solar and Stellar Astrophysics · Physics 2016-09-28 W. T. Barnes , P. J. Cargill , S. J. Bradshaw

We present a detailed analysis of a 3D MHD simulation of a subset of the magnetic flux in an active region. The simulation models the generation of nanoflares and response of the plasma to imposed photospheric motions. Our study focuses on…

Solar and Stellar Astrophysics · Physics 2025-09-26 Shanwlee Sow Mondal , Lars K. S. Daldorff , James A. Klimchuk , Craig D. Johnston

The solar corona, the tenuous outer atmosphere of the Sun, is orders of magnitude hotter than the solar surface. This 'coronal heating problem' requires the identification of a heat source to balance losses due to thermal conduction,…

Solar and Stellar Astrophysics · Physics 2015-10-06 Ineke De Moortel , Philippa Browning

We analyzed the occurrence rates of flares on stars of spectral types K, G, F, and A, observed by Kepler. We found that the histogram of occurrence frequencies of stellar flares is systematically shifted towards a high-energy tail for…

Solar and Stellar Astrophysics · Physics 2017-03-15 M. Svanda , M. Karlicky

It has been proposed that the million degree temperature of the corona is due to the combined effect of barely-detectable energy releases, so called nanoflares, that occur throughout the solar atmosphere. Alas, the nanoflare density and…

Solar and Stellar Astrophysics · Physics 2015-05-27 M. R. Bareford , P. K. Browning , R. A. M. Van der Linden

The corona is a structure possessed by stars, including the sun. The abnormal heating of the solar corona and chromosphere is one of the greatest mysteries in modern astronomy. While state-of-the-art observations have identified some…

Solar and Stellar Astrophysics · Physics 2024-01-08 K. J. Li , J. C. Xu , W. F eng , J. L. Xie , X. J. Shi , L. H. Deng

The coronal heating problem is one of the most critical challenges in solar physics. Recent observations have revealed that small-scale swirls are ubiquitous in the photosphere and chromosphere, suggesting that they may play a significant…

Solar and Stellar Astrophysics · Physics 2025-08-21 Hidetaka Kuniyoshi , Shinsuke Imada , Takaaki Yokoyama

In a recent computational campaign [Ng et al., Astrophys. J. 747, 109, 2012] to investigate a three-dimensional model of coronal heating using reduced magnetohydrodynamics (RMHD), we have obtained scaling results of heating rate versus…

Solar and Stellar Astrophysics · Physics 2015-06-05 C. S. Ng , L. Lin