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Related papers: Magnetic Braiding and Parallel Electric Fields

200 papers

We estimate the energy input into the solar corona from photospheric footpoint motions, using observations of a plage region by the Hinode Solar Optical Telescope. Assuming a perfectly ideal coronal evolution, two alternative lower bounds…

Solar and Stellar Astrophysics · Physics 2014-05-08 A. R. Yeates , F. Bianchi , B. T. Welsch , P. J. Bushby

Parker's coronal braiding and nanoflaring scenario predicts the development of tangential discontinuities and highly misaligned magnetic field lines, as a consequence of random buffeting of their footpoints due to the action of…

Solar and Stellar Astrophysics · Physics 2018-08-17 M. J. Aschwanden , A. A van Ballegooijen

Magnetic reconnection is a fundamental process in a plasma that facilitates the release of energy stored in the magnetic field by permitting a change in the magnetic topology. In this article we present a review of the current state of…

Solar and Stellar Astrophysics · Physics 2012-07-04 D. I. Pontin

The dynamics of magnetic fields in closed regions of solar and stellar coronae are investigated with a reduced magnetohydrodynamic (MHD) model in the framework of Parker scenario for coronal heating. A novel analysis of reduced MHD…

Solar and Stellar Astrophysics · Physics 2015-12-04 A. F. Rappazzo

In laboratory and natural plasmas of practical interest, the spatial scale $\Delta_d$ at which magnetic field lines lose distinguishability differs enormously from the scale $a$ of magnetic reconnection across the field lines. In the solar…

Plasma Physics · Physics 2021-06-30 Allen H Boozer , Todd Elder

Context: The majority of studies on stressed 3D magnetic null points consider magnetic reconnection driven by an external perturbation, but the formation of a genuine current sheet equilibrium remains poorly understood. This problem has…

Solar and Stellar Astrophysics · Physics 2012-09-07 Jorge Fuentes-Fernandez , Clare E. Parnell

We use a numerical nonlinear multigrid magnetic relaxation technique to investigate the generation of current sheets in three-dimensional magnetic flux braiding experiments. We are able to catalogue the relaxed nonlinear force-free…

Astrophysics · Physics 2009-10-31 A. W. Longbottom , G. J. Rickard , I. J. D. Craig , A. D. Sneyd

Using superposition and numerical approximations of a published analytical expression for the magnetic field generated by a finite solenoid, we show that the magnetic field external to parallel identical solenoids can be nearly uniform and…

Classical Physics · Physics 2017-12-05 Melody Xuan Lim , Henry Greenside

We demonstrate that conservation of global helicity plays only a minor role in determining the nature and consequences of magnetic reconnection in the solar atmosphere. First, we show that observations of the solar coronal magnetic field…

Astrophysics · Physics 2015-06-24 Spiro K. Antiochos , C. Richard DeVore

Magnetic fields and flows in coronal structures, for example, in gradual phases in flares, can be described by 2D and 3D magnetohydrostatic (MHS) and steady magnetohydrodynamic (MHD) equilibria. Within a physically simplified, but exact…

Solar and Stellar Astrophysics · Physics 2014-09-17 D. H. Nickeler , M. Karlicky , T. Wiegelmann , M. Kraus

Twisted coronal loops should be ubiquitous in the solar corona. Twisted magnetic fields contain excess magnetic energy, which can be released during magnetic reconnection, causing solar flares. The aim of this work is to investigate…

Solar and Stellar Astrophysics · Physics 2015-01-27 Mykola Gordovskyy , Philippa Browning , Eduard Kontar , Nicolas Bian

We present the results of a set of three-dimensional numerical simulations of magnetic flux emergence from below the photosphere into the corona that include a uniform and horizontal coronal magnetic field mimicking a pre-existing…

Astrophysics · Physics 2009-11-10 K. Galsgaard , F. Moreno-Insertis , V. Archontis , A. Hood

In this paper, we investigate a simple model where two, initially unconnected, flux systems are forced to interact in response to the imposed boundary driving by solving the non-ideal 3D MHD equations numerically. The reconnection rate of…

Astrophysics · Physics 2007-05-23 K. Galsgaard , C. Parnell

Magnetic-field reconnection is believed to play a fundamental role in magnetized plasma systems throughout the Universe1, including planetary magnetospheres, magnetars and accretion disks around black holes. This letter present extreme…

Solar and Stellar Astrophysics · Physics 2015-02-06 Yang Su , Astrid M. Veronig , Gordon D. Holman , Brian R. Dennis , Tongjiang Wang , Manuela Temmer , Weiqun Gan

We use our semi-analytic solution of the nonlinear force-free field equation to construct three-dimensional magnetic fields that are applicable to the solar corona and study their statistical properties for estimating the degree of braiding…

Solar and Stellar Astrophysics · Physics 2017-12-05 A. Mangalam , A. Prasad

We present a model for separator reconnection due to an isolated reconnection process. Separator reconnection is a process which occurs in the neighbourhood of a distinguished field line (the separator) connecting two null points of a…

Solar and Stellar Astrophysics · Physics 2015-05-28 A. L. Wilmot-Smith , G. Hornig

Numerous observations have revealed that power-law distributions are ubiquitous in energetic solar processes. Hard X-rays, soft X-rays, extreme ultraviolet radiation, and radio waves all display power-law frequency distributions. Since…

Solar and Stellar Astrophysics · Physics 2018-02-14 Kalman J. Knizhnik , Vadim M. Uritsky , James A. Klimchuk , C. Richard DeVore

We investigate electron acceleration resulting from 3D magnetic reconnection between an emerging, twisted magnetic flux rope and a pre-existing weak, open magnetic field. We first follow the rise of an unstable, twisted flux tube with a…

Solar and Stellar Astrophysics · Physics 2012-11-07 G. Baumann , Å. Nordlund

Solar flares are accessible to a broad variety of observational methods to see and investigate the {\em magnetic reconnection} phenomenon in high-temperature strongly-magnetized plasma of the solar corona. An analysis of the topological…

Solar and Stellar Astrophysics · Physics 2009-01-30 Boris V. Somov

Forced magnetic reconnection, a reconnection event triggered by external perturbation, should be ubiquitous in the solar corona. Energy released during such cases can be much greater than that which was introduced by the perturbation. It is…

Solar and Stellar Astrophysics · Physics 2019-02-27 Max Potter , Philippa Browning , Mykola Gordovskyy