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Related papers: Torsional Oscillations in a Global Solar Dynamo

200 papers

Young solar-type stars rotate rapidly and many are magnetically active; some undergo magnetic cycles similar to the 22-year solar activity cycle. We conduct simulations of dynamo action in rapidly rotating suns with the 3D MHD anelastic…

Solar and Stellar Astrophysics · Physics 2011-03-28 Benjamin P. Brown , Mark S. Miesch , Matthew K. Browning , Allen Sacha Brun , Juri Toomre

Rotational shear layers at the boundary between radiative and convective zones, tachoclines, play a key role in the process of magnetic field generation in solar-like stars. We present two sets of global simulations of rotating turbulent…

Solar and Stellar Astrophysics · Physics 2016-03-08 G. Guerrero , P. K. Smolarkiewicz , E. M. de Gouveia Dal Pino , A. G. Kosovichev , N. N. Mansour

The expansion of the rotating fluid will change the vorticity and rotational speed of the expanding region. In turbulent thermal convection, this microscopic effect is preserved. Tracking the fluid micelles shows that the average vorticity…

Solar and Stellar Astrophysics · Physics 2023-01-03 Haibin Chen , Rong Wu

We extend earlier models of turbulent dynamos with an upper, nearly force-free exterior to spherical geometry, and study how flux emerges from lower layers to the upper ones without being driven by magnetic buoyancy. We also study how this…

Solar and Stellar Astrophysics · Physics 2011-09-26 Jörn Warnecke , Axel Brandenburg , Dhrubaditya Mitra

Convective turbulent motions in the solar interior, as well as the mean flows resulting from them, determine the evolution of the solar magnetic field. With the aim to get a better understanding of these flows we study anelastic rotating…

Solar and Stellar Astrophysics · Physics 2015-06-12 G. Guerrero , P. K. Smolarkiewicz , A. Kosovichev , N. Mansour

Self-organization properties of sustained magnetized plasma are applied to selected solar data to understand solar magnetic fields. Torsional oscillations are speed-up and slow-down bands of the azimuthal flow that correlate with the solar…

Solar and Stellar Astrophysics · Physics 2018-07-26 T. R. Jarboe , T. E. Benedett , C. J. Everson , C. J. Hansen , A. C. Hossack , K. D. Morgan , B. A. Nelson , J. M. Penna , D. A. Sutherland

The form of the solar meridional circulation is a very important ingredient for mean field flux transport dynamo models. Yet a shroud of mystery still surrounds this large-scale flow, given that its measurement using current helioseismic…

Solar and Stellar Astrophysics · Physics 2015-02-17 Dario Passos , Paul Charbonneau , Mark Miesch

A model for the solar dynamo, consistent in global flow and numerical method employed with the differential rotation model, is developed. The magnetic turbulent diffusivity is expressed in terms of the entropy gradient, which is controlled…

Solar and Stellar Astrophysics · Physics 2017-06-28 L. L. Kitchatinov , A. A. Nepomnyashchikh

We live near a magnetic star whose cycles of activity are driven by dynamo action beneath the surface. In the solar convection zone, rotation couples with plasma motions to build highly organized magnetic fields that erupt at the surface…

Solar and Stellar Astrophysics · Physics 2015-05-20 Benjamin P Brown

For moderate and slow rotation, magnetic activity of solar-like stars is observed to strongly depend on rotation. These observations do not yet have a solid explanation in terms of dynamo theory. We aim to find such an explanation by…

Solar and Stellar Astrophysics · Physics 2020-10-07 J. Warnecke , M. J. Käpylä

The goal of this research is to investigate how well various turbulence models can describe physical properties of the upper convective boundary layer of the Sun. An accurate modeling of the turbulence motions is necessary for understanding…

Astrophysics · Physics 2009-11-13 L. Jacoutot , A. G. Kosovichev , A. Wray , N. N. Mansour

Three-dimensional magnetohydrodynamical large eddy simulations of solar surface convection using realistic model physics is conducted. The effects of magnetic fields on thermal structure of convective motions into radiative layers, the…

Astrophysics · Physics 2007-05-23 Sergey Ustyugov

We present axisymmetric simulations of the coupled convective and radiative regions in the Sun in order to investigate the angular momentum evolution of the radiative interior. Both hydrodynamic and magnetohydrodynamic models were run. We…

Solar and Stellar Astrophysics · Physics 2015-05-28 T. M. Rogers

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

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…

Simulating deep solar convection and its coupled mean-field motions is a formidable challenge where few observational results constrain models that suffer from the non-physical influence of the grid resolution. We present hydrodynamic…

Solar and Stellar Astrophysics · Physics 2022-12-07 G. Guerrero , A. M. Stejko , A. G. Kosovichev , P. K Smolarkiewicz , A. Strugarek

Inertial modes have been recently detected in the Sun via helioseismology, yet their origin, evolution, and role in the dynamics of the solar plasma and magnetic field remain poorly understood. In this study, we employ global numerical…

The solar dynamo and the solar Global internal Magnetic Structure (GMS) appear to be a thin ($\sim$2 Mm thick) structure near ($\sim$1 Mm below) the solar surface. Evidence for these properties are found from the amplitude of the torsional…

Solar and Stellar Astrophysics · Physics 2017-12-05 T. R. Jarboe , T. E. Benedett , C. J. Everson , C. J. Hansen , A. C. Hossack , K. D. Morgan , B. A. Nelson , J. M. Penna , D. A. Sutherland

(abidged) Context: Stellar convection zones are characterized by vigorous high-Reynolds number turbulence at low Prandtl numbers. Aims: We study the dynamo and differential rotation regimes at varying levels of viscous, thermal, and…

Solar and Stellar Astrophysics · Physics 2017-02-22 P. J. Käpylä , M. J. Käpylä , N. Olspert , J. Warnecke , A. Brandenburg

Increasing evidence is becoming available about not only the surface differential rotation of rapidly rotating cool stars but, in a small number of cases, also about temporal variations, which possibly are analogous to the solar torsional…

Astrophysics · Physics 2009-11-10 E. Covas , D. Moss , R. Tavakol