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Related papers: Fluctuation dynamo based on magnetic reconnections

200 papers

We develop a new model of the fluctuation dynamo in which the magnetic field is confined in thin flux ropes advected by a multi-scale flow modeling turbulence. Magnetic dissipation occurs only via reconnection of the flux ropes. We…

Solar and Stellar Astrophysics · Physics 2010-06-16 Andrew W. Baggaley , Carlo F. Barenghi , Anvar Shukurov , Kandaswamy Subramanian

Twisted magnetic flux ropes are reservoirs of free magnetic energy. In a highly-conducting plasma such as the solar corona, energy release through multiple magnetic reconnections can be modelled as a helicity-conserving relaxation to a…

Solar and Stellar Astrophysics · Physics 2023-08-17 Philippa Browning , Mykola Gordovskyy , Alan Hood

A theory for the heating of coronal magnetic flux ropes is developed. The dissipated magnetic energy has two distinct contributions: (1) energy injected into the corona as a result of granule-scale, random footpoint motions, and (2) energy…

Astrophysics · Physics 2009-11-13 A. A. van Ballegooijen , S. R. Cranmer

The presence of magnetic fields in many astrophysical objects is due to dynamo action, whereby a part of the kinetic energy is converted into magnetic energy. A turbulent dynamo that produces magnetic field structures on the same scale as…

Astrophysics of Galaxies · Physics 2020-03-19 Amit Seta , Paul J. Bushby , Anvar Shukurov , Toby S. Wood

Twisted magnetic flux ropes are ubiquitous in space and laboratory plasmas, and the merging of such flux ropes through magnetic reconnection is an important mechanism for restructuring magnetic fields and releasing free magnetic energy. The…

Plasma Physics · Physics 2015-12-09 P. K. Browning , S. Cardnell , M. Evans , F. Arese Lucini , V. S. Lukin , K. G. McClements , A. Stanier

In this work we study the process of energy dissipation triggered by a slow large scale motion of a magnetized conducting fluid. Our consideration is motivated by the problem of heating the solar corona, which is believed to be governed by…

Solar and Stellar Astrophysics · Physics 2015-10-14 P. Pongkitiwanichakul , F. Cattaneo , S. Boldyrev , J. Mason , J. C. Perez

We present a model for plasma heating produced by time-dependent, spatially localized reconnection within a flare current sheet separating skewed magnetic fields. The reconnection creates flux tubes of new connectivity which subsequently…

Solar and Stellar Astrophysics · Physics 2015-05-19 Silvina Guidoni , Dana Longcope

A magnetically dominated plasma driven by motions on boundaries at which magnetic field lines are anchored is forced to dissipate the work being done upon it, no matter how small the electrical resistivity. Numerical experiments have…

Astrophysics · Physics 2007-05-23 Aake Nordlund

Fluctuation dynamos provide a robust mechanism for amplifying weak seed magnetic fields in turbulent astrophysical plasmas. However, their behaviour in the highly compressible regimes characteristic of the interstellar medium remains…

Astrophysics of Galaxies · Physics 2026-02-18 Ameya Uday Nagdeo , Sharanya Sur , Bhargav Vaidya

Magnetic fields in several astrophysical objects are amplified and maintained by a dynamo mechanism, which is the conversion of the turbulent kinetic energy to magnetic energy. A dynamo that amplifies magnetic fields at scales $<$ the…

Astrophysics of Galaxies · Physics 2021-09-27 Amit Seta , Christoph Federrath

Self-organization in continuous systems is associated with dissipative processes. In particular, for magnetized plasmas, it is known as magnetic relaxation, where the magnetic energy is converted into heat and kinetic energy of flow through…

Solar and Stellar Astrophysics · Physics 2024-01-23 Satyam Agarwal , Ramit Bhattacharyya , Shangbin Yang

We perform direct numerical simulations of an externally driven two-dimensional magnetohydrodynamic system over extended periods of time to simulate the dynamics of a transverse section of a solar coronal loop. A stationary and large-scale…

Astrophysics · Physics 2009-10-30 Pablo Dmitruk , Daniel O. Gomez

Magnetic reconnection is a fundamental plasma process that converts magnetic energy into bulk flow energy, thermal energy, and nonthermal particle acceleration. Despite its importance, the statistical properties of the turbulent…

Astrophysics of Galaxies · Physics 2025-12-16 Yue Hu , Luca Comisso , Lorenzo Sironi , Siyao Xu

We perform a high-resolution two-dimensional fully-kinetic numerical simulation of a turbulent plasma system with observation-driven conditions, in order to investigate the interplay between turbulence, magnetic reconnection, and particle…

The structure of electric current and magnetic helicity in the solar corona is closely linked to solar activity over the 11-year cycle, yet is poorly understood. As an alternative to traditional current-free "potential field"…

Solar and Stellar Astrophysics · Physics 2015-05-18 A. R. Yeates , J. A. Constable , P. C. H. Martens

Energy dissipation in collisionless plasmas is one of the most outstanding open questions in plasma physics. Magnetic reconnection and turbulence are two phenomena that can produce the conditions for energy dissipation. These two phenomena…

Solar coronal mass ejections are the most energetic events in the Solar System. In their standard formation model, a magnetic flux rope builds up into a coronal mass ejection through magnetic reconnection that continually converts…

Solar and Stellar Astrophysics · Physics 2023-05-08 Tingyu Gou , Rui Liu , Astrid M. Veronig , Bin Zhuang , Ting Li , Wensi Wang , Mengjiao Xu , Yuming Wang

Magnetic reconnection at the interface between coronal holes and loops, so-called interchange reconnection, can release the hotter, denser plasma from magnetically confined regions into the heliosphere, contributing to the formation of the…

Solar and Stellar Astrophysics · Physics 2015-03-13 A. F. Rappazzo , W. H. Matthaeus , D. Ruffolo , S. Servidio , M. Velli

The structure of magnetic flux ropes injected into the solar wind during reconnection in the coronal atmosphere is explored with particle-in-cell simulations and compared with in situ measurements of magnetic "switchbacks" from the Parker…

The discrete nature of the solar magnetic field as it emerges into the corona through the photosphere indicates that it exists as isolated flux tubes in the convection zone, and will remain as discrete flux tubes in the corona until it…

Astrophysics · Physics 2009-11-10 M. G. Linton , S. K. Antiochos
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