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Related papers: Torsional Oscillations in a Global Solar Dynamo

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Flux-dominated solar dynamo models have demonstrated to reproduce the main features of the large scale solar magnetic cycle, however the use of a solar like differential rotation profile implies in the the formation of strong toroidal…

Astrophysics · Physics 2009-11-13 G. A. Guerrero , E. M. de G. Dal Pino

We present detailed numerical calculations of the fast solar tachocline based on the assumption that the dynamo field dominates over the dynamics of the tachocline. In the present paper of the series, we focus on three shortfalls of the…

Astrophysics · Physics 2007-05-23 E. Forgacs-Dajka

The solar convection zone rotates differentially, with its equatorial region rotating more rapidly than the polar regions. This form of differential rotation, also observed in many other low-mass stars, is understood to arise when Coriolis…

Solar and Stellar Astrophysics · Physics 2022-10-26 Maria E. Camisassa , Nicholas A. Featherstone

We investigate the confinement and long-term dynamics of the magnetised solar tachocline. Starting from first principles, we derive the values of turbulent transport coefficients and then explore the implications for the confinement and…

Astrophysics · Physics 2008-11-26 Eun-Jin Kim , Nicolas Leprovost

We investigate the role of magnetic helicity in promoting cyclic magnetic activity in a global, 3D, magnetohydrodynamic (MHD) simulation of a convective dynamo. This simulation is characterized by coherent bands of toroidal field that exist…

Solar and Stellar Astrophysics · Physics 2016-06-15 Mark S. Miesch , Mei Zhang , Kyle C. Augustson

The dynamo mechanism, responsible for the solar magnetic activity, is still an open problem in astrophysics. Different theories proposed to explain such phenomena have failed in reproducing the observational properties of the solar…

Solar and Stellar Astrophysics · Physics 2020-09-30 G Guerrero

We study the evolution of turbulence in the solar wind by solving numerically the full 3D magneto-hydrodynamic (MHD) equations embedded in a radial mean wind. The corresponding equations (expanding box model or EBM) have been considered…

Solar and Stellar Astrophysics · Physics 2015-06-22 Yue Dong , Andrea Verdini , Roland Grappin

The differential rotation of the sun, as deduced from helioseismology, exhibits a prominent radial shear layer near the top of the convection zone wherein negative radial gradients of angular velocity are evident in the low- and…

Astrophysics · Physics 2009-11-07 M. L. DeRosa , P. A. Gilman , J. Toomre

Context. Solar eruptions and high flare activity often accompany the rapid rotation of sunspots. The study of sunspot rotation and the mechanisms driving this motion are therefore key to our understanding of how the solar atmosphere attains…

Solar and Stellar Astrophysics · Physics 2015-10-14 Z. Sturrock , A. W. Hood , V. Archontis , C. M. McNeill

The exact location of the solar dynamo remains uncertain--whether it operates primarily in the near-surface shear layer, throughout the entire convection zone, or near the tachocline, a region of sharp transition in the solar rotation,…

Solar and Stellar Astrophysics · Physics 2026-01-07 Krishnendu Mandal , Alexander G. Kosovichev

We present results from compressible Cartesian convection simulations with and without imposed shear. In the former case the dynamo is expected to be of $\alpha^2\varOmega$ type which is generally expected to be relevant for the Sun,…

Solar and Stellar Astrophysics · Physics 2013-11-19 P. J. Käpylä , M. J. Mantere , A. Brandenburg

Young solar-type stars rotate rapidly and are very magnetically active. The magnetic fields at their surfaces likely originate in their convective envelopes where convection and rotation can drive strong dynamo action. Here we explore…

Solar and Stellar Astrophysics · Physics 2011-01-04 Benjamin P Brown , Matthew K Browning , Allan Sacha Brun , Mark S Miesch , Juri Toomre

We present a formalism for investigating the interaction between pmode oscillations and convection by analyzing realistic, three-dimensional simulations of the near-surface layers of the solar convection zone. By choosing suitable…

Astrophysics · Physics 2009-10-31 Å. Nordlund , R. F. Stein

In this paper we discuss a dynamic flux-transport dynamo model that includes the feedback of the induced magnetic field on differential rotation and meridional flow. We consider two different approaches for the feedback: meanfield Lorentz…

Astrophysics · Physics 2009-11-11 Matthias Rempel

We present the results of 3--D nonlinear simulations of magnetic dynamo action by core convection within A-type stars of 2 solar masses, at a range of rotation rates. We consider the inner 30% by radius of such stars, with the spherical…

Astrophysics · Physics 2009-11-10 Matthew Browning , Allan Sacha Brun , Juri Toomre

In this paper, we present a model for the effects of the tachocline on the differential rotation in the solar convection zone. The mathematical technique relies on the assumption that entropy is nearly constant ("well-mixed") in isorotation…

Solar and Stellar Astrophysics · Physics 2015-05-19 Steven A. Balbus , Henrik N. Latter

Solar eruptions are the leading driver of space weather, and it is vital for space weather forecast to understand in what conditions the solar eruptions can be produced and how they are initiated. The rotation of sunspots around their…

Solar and Stellar Astrophysics · Physics 2023-08-15 Chaowei Jiang , Xueshang Feng , Xinkai Bian , Peng Zou , Aiying Duan , Xiaoli Yan , Qiang Hu , Wen He , Xinyi Wang , Pingbing Zuo , Yi Wang

We use the three-dimensional hydrodynamic code of Stein and Nordlund to realistically simulate the upper layers of the solar convection zone in order to study physical characteristics of solar oscillations. Our first result is that the…

Astrophysics · Physics 2009-10-31 D. Georgobiani , A. G. Kosovichev , R. Nigam , A. Nordlund , R. F. Stein

We use three-dimensional direct numerical simulations of the helically forced magnetohydrodynamic equations in spherical shell segments in order to study the effects of changes in the geometrical shape and size of the domain on the growth…

Astrophysics · Physics 2010-01-15 Dhrubaditya Mitra , Reza Tavakol , Axel Brandenburg , David Moss

In the outer envelope of the Sun and in other stars, differential rotation and meridional circulation are maintained via the redistribution of momentum and energy by convective motions. In order to properly capture such processes in a…

Astrophysics · Physics 2009-11-13 M. S. Miesch