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Related papers: Coronal influence on dynamos

200 papers

We present the first results from three-dimensional spherical shell simulations of magnetic dynamo action realized by turbulent convection penetrating downward into a tachocline of rotational shear. This permits us to assess several…

Astrophysics · Physics 2011-02-11 Matthew Browning , Mark S. Miesch , Allan Sacha Brun , Juri Toomre

An integrated Magneto-Fluid model, that accords full treatment to the Velocity fields associated with the directed plasma motion, is developed to investigate the dynamics of coronal structures. It is suggested that the interaction of the…

Coronal holes are the darkest and least active regions of the Sun, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed…

Solar and Stellar Astrophysics · Physics 2015-05-14 Steven R. Cranmer

Aims. The goal is to employ a 3D magnetohydrodynamics (MHD) model including spectral synthesis to model the corona in an observed solar active region. This will allow us to judge the merits of the coronal heating mechanism built into the 3D…

Solar and Stellar Astrophysics · Physics 2017-09-19 Ph. -A. Bourdin , S. Bingert , H. Peter

We study extreme-ultraviolet emission line spectra derived from three-dimensional magnetohydrodynamic models of structures in the corona. In order to investigate the effects of increased magnetic activity at photospheric levels in a…

Solar and Stellar Astrophysics · Physics 2009-04-16 Pia Zacharias , Sven Bingert , Hardi Peter

The motivation for considering distributed large scale dynamos in the solar context is reviewed in connection with the magnetic helicity constraint. Preliminary accounts of 3-dimensional direct numerical simulations (in spherical shell…

Astrophysics · Physics 2011-11-10 A. Brandenburg , P. J. Käpylä , D. Mitra , D. Moss , R. Tavakol

The main object of the paper is to present the condition of the non-diffusive part of the Reynolds stress for driving the double-cell structure of the solar meridional circulation, which has been revealed by recent helioseismic…

Solar and Stellar Astrophysics · Physics 2017-01-25 Yuto Bekki , Takaaki Yokoyama

Coronal jets are collimated, dynamic events that occur over a broad range of spatial scales in the solar corona. In the open magnetic field of coronal holes, jets form quasi-radial spires that can extend far out into the heliosphere, while…

Solar and Stellar Astrophysics · Physics 2016-04-06 P. F. Wyper , C. R. DeVore

Given a known radial magnetic field distribution on the Sun's photospheric surface, there exist well-established methods for computing a potential magnetic field in the corona above. Such potential fields are routinely used as input to…

Solar and Stellar Astrophysics · Physics 2021-12-22 Oliver E. K. Rice , Anthony R. Yeates

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

Determining the mechanisms responsible for the heating of the coronal plasma and maintaining and accelerating the solar wind are long standing goals in solar physics. There is a clear need to constrain the energy, mass and momentum flux…

Solar and Stellar Astrophysics · Physics 2016-11-21 R. J. Morton , E. Scullion , D. S. Bloomfield , J. A. McLaughlin , S. Regnier , S. W. McIntosh , S. Tomczyk , P. Young

In the solar convection zone, rotation couples with intensely turbulent convection to drive a strong differential rotation and achieve complex magnetic dynamo action. Our sun must have rotated more rapidly in its past, as is suggested by…

In this chapter, we explore how gravitational interactions drive turbulent flows inside planetary cores and provide an interesting alternative to convection to explain dynamo action and magnetic fields around terrestrial bodies. In the…

Geophysics · Physics 2019-07-04 Thomas Le Reun , Michael Le Bars

We carry out a magneto-hydrodynamic (MHD) simulation of convective dynamo in the rotating solar convective envelope driven by the solar radiative diffusive heat flux. The simulation is similar to that reported in Fan & Fang (2014) but with…

Solar and Stellar Astrophysics · Physics 2016-01-12 Yuhong Fan , Fang Fang

Helioseismology has discovered a thin layer beneath the solar surface where the rotation rate increases rapidly with depth. The normalized rotational shear in the upper 10 Mm of the layer is constant with latitude. Differential rotation…

Solar and Stellar Astrophysics · Physics 2023-11-27 Leonid Kitchatinov

The canonical undestanding of stellar convection has recently been put under doubt due to helioseismic results and global 3D convection simulations. This "convective conundrum" is manifested by much higher velocity amplitudes in simulations…

Solar and Stellar Astrophysics · Physics 2024-12-25 Petri J. Käpylä

We present a new scenario for magnetic field amplification where an electrically conducting fluid is confined in a differentially rotating, spherical shell with thin aspect-ratio. When the angular momentum sufficiently decreases outwards,…

Fluid Dynamics · Physics 2016-06-14 Florence Marcotte , Christophe Gissinger

Spectropolarimetric observations show that many low-mass stars possess large-scale poloidal magnetic fields with considerable dipole component, which in some cases exhibit temporal dynamics - cycles or reversals. Although it is widely…

Solar and Stellar Astrophysics · Physics 2025-07-02 Anna Guseva , Ludovic Petitdemange , Charly Pinçon

Dynamo action refers to energy exchange processes through which magnetic fields are generated at the expense of kinetic energy of the plasma flows. Dynamos can generate magnetic fields across scales larger or smaller than the flows…

The coming decade will see the routine use of solar data of unprecedented spatial and spectral resolution, time cadence, and completeness. To capitalize on the new (or soon to be available) facilities such as SDO, ATST and FASR, and the…