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Related papers: Dipolar versus multipolar dynamos: the influence o…

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Simulations of magnetohydrodynamics convection in slowly rotating stars predict anti-solar differential rotation (DR) in which the equator rotates slower than poles. This anti-solar DR in the usual $\alpha \Omega$ dynamo model does not…

Solar and Stellar Astrophysics · Physics 2020-01-01 Bidya Binay Karak , Aparna Tomar , Vindya Vashishth

Rotation has a number of important effects on the evolution of stars. It decreases the surface gravity, causes enhanced mass loss and leads to surface abundance anomalies of various chemical isotopes. We have adapted the Cambridge stellar…

Solar and Stellar Astrophysics · Physics 2012-05-31 Adrian T. Potter

The outer areas of Jupiter and Saturn have multiple zonal winds, reaching the high latitudes, that penetrate deep into the planets' interiors, as suggested by gravity measurements. These characteristics are replicable in numerical…

Earth and Planetary Astrophysics · Physics 2024-02-02 Paula N. Wulff , Ulrich R. Christensen , Wieland Dietrich , Johannes Wicht

We present numerical simulations of a self-sustaining magnetic field in a differentially rotating non-convective stellar interior. A weak initial field is wound up by the differential rotation; the resulting azimuthal field becomes unstable…

Astrophysics · Physics 2009-11-11 J. Braithwaite , H. C. Spruit

Observations in polarized emission reveal the existence of large-scale coherent magnetic fields in a wide range of spiral galaxies. Radio-polarization data show that these fields are strongly inclined towards the radial direction, with…

Astrophysics · Physics 2009-11-13 Oliver Gressel , Udo Ziegler , Detlef Elstner , Günther Rüdiger

During stellar evolution, especially in the PMS, stellar structure and rotation evolve significantly causing major changes in the dynamics and global flows of the star. We wish to assess the consequences of these changes on stellar dynamo,…

Solar and Stellar Astrophysics · Physics 2017-09-15 Constance Emeriau-Viard , Allan Sacha Brun

M-dwarf stars are well known for the intense magnetic activity that many of them exhibit. In cool stars with near-surface convection zones, this magnetic activity is thought to be driven largely by the interplay of convection and the large…

Solar and Stellar Astrophysics · Physics 2022-03-30 Connor P. Bice , Juri Toomre

Context: Convectively-driven flows play a crucial role in the dynamo processes that are responsible for producing magnetic activity in stars and planets. It is still not fully understood why many astrophysical magnetic fields have a…

Solar and Stellar Astrophysics · Physics 2018-05-09 P. J. Bushby , P. J. Käpylä , Y. Masada , A. Brandenburg , B. Favier , C. Guervilly , M. J. Käpylä

We develop a model based on 3D mean-field MHD for the generation of large scale magnetic fields in fully convective objects like low-mass stars, brown dwarfs and possibly gaseous planets. The dynamo process is of alpha^2 type and thus…

Astrophysics · Physics 2016-08-30 Gilles Chabrier , Manfred Kueker

Despite progress in the observations of stellar magnetic fields, their physical mechanisms remain poorly understood. During the pre-main sequence (PMS) phase, the inner layers of stars contract and a radiative core gradually develops. In…

Solar and Stellar Astrophysics · Physics 2026-02-25 A. Guseva , L. Manchon , L. Petitdemange , C. Pinçon

To explore the physics of large-scale flows in solar-like stars, we perform 3D anelastic simulations of rotating convection for global models with stratification resembling the solar interior. The numerical method is based on an implicit…

Solar and Stellar Astrophysics · Physics 2013-12-10 G. Guerrero , P. K. Smolarkiewicz , A. G. Kosovichev , N. N. Mansour

This paper provides a brief overview of dynamo scaling relationships for the degree of equipartition between magnetic and kinetic energies. Three basic approaches are adopted to explore these scaling relationships, with a first look at two…

Solar and Stellar Astrophysics · Physics 2017-01-11 Kyle Augustson , Stéphane Mathis , Allan Sacha Brun

Convectively driven dynamos with rotation generating magnetic fields on scales large compared with the scale of the turbulent eddies are being reviewed. It is argued that such fields can be understood as the result of an alpha effect.…

Solar and Stellar Astrophysics · Physics 2011-08-19 A. Brandenburg , P. J. Käpylä , M. J. Korpi

Rotation evolution of late-type stars is dominated by magnetic braking and the underlying factors that control this angular momentum loss are important for the study of stellar spin-down. In this work, we study angular momentum loss as a…

Solar and Stellar Astrophysics · Physics 2015-11-04 Cecilia Garraffo , Jeremy J. Drake , Ofer Cohen

Late-type stars rotate differentially owing to anisotropic turbulence in their outer convection zones. The rotation is called solar-like (SL) when the equator rotates fastest and anti-solar (AS) otherwise. Hydrodynamic simulations show a…

Solar and Stellar Astrophysics · Physics 2015-03-25 Bidya Binay Karak , Petri J. Kapyla , Maarit J. Kapyla , Axel Brandenburg , N. Olspert , J. Pelt

The present study aims at studying the flow and field produced by a stellar radiative zone which is initially made to rotate differentially in the presence of a large-scale poloidal magnetic field threading the whole domain. We focus both…

Solar and Stellar Astrophysics · Physics 2020-09-02 L. Jouve , F. Lignières , M. Gaurat

A convection-driven MHD dynamo in a rotating spherical shell, with clearly defined structural elements in the flow and magnetic field, is simulated numerically. Such dynamos can be called deterministic, in contrast to those explicitly…

Astrophysics · Physics 2008-11-26 A. V. Getling , R. D. Simitev , F. H. Busse

Magnetic fields pervade astrophysical systems and strongly influence their dynamics. Because magnetic diffusion is usually much faster than system evolution, ancient fields cannot explain the present magnetization of planets, stars, and…

Earth and Planetary Astrophysics · Physics 2025-12-11 Albert Elias-López

Using a rotating flat layer heated from below as an example, we consider effects which lead to stabilizing an exponentially growing magnetic field in magnetostrophic convection in transition from the kinematic dynamo to the full non-linear…

Fluid Dynamics · Physics 2015-05-18 P. Hejda , M. Reshetnyak

One interpretation of the activity and magnetism of late-type stars is that these both intensify with decreasing Rossby number up to a saturation level, suggesting that stellar dynamos depend on both rotation and convective turbulence. Some…

Solar and Stellar Astrophysics · Physics 2020-03-23 Jyri J. Lehtinen , Federico Spada , Maarit J. Käpylä , Nigul Olspert , Petri J. Käpylä