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Related papers: Three-Layer Magnetoconvection

200 papers

Magnetic fields play a crucial role at all stages of the formation of low mass stars and planetary systems. In the final stages, in particular, they control the kinematics of in-falling gas from circumstellar discs, and the launching and…

Solar and Stellar Astrophysics · Physics 2015-05-19 S. G. Gregory , M. Jardine , C. G. Gray , J. -F. Donati

A completely new mechanism to generate the observed amount of large-scale cosmological magnetic fields is introduced in the context of three-form inflation. The amplification of the fields occurs via fourth order dynamics of the vector…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-17 Tomi S. Koivisto , Federico R. Urban

We investigate an intensification mechanism for the magnetic field near the base of the solar convection zone that does not rely on differential rotation. Such mechanism in addition to differential rotation has been suggested by studies of…

Solar and Stellar Astrophysics · Physics 2015-06-11 H. Hotta , M. Rempel , T. Yokoyama

Various types of magnetic fields occur in stars: small scale fields, large scale fields, and internal toroidal fields. While the latter may be ubiquitous in stars due to differential rotation, small scale fields (spots) may be associated…

Solar and Stellar Astrophysics · Physics 2015-06-18 N. Langer

Large-scale dipolar surface magnetic fields have been detected in a fraction of OB stars, however only few stellar evolution models of massive stars have considered the impact of these fossil fields. We are performing 1D hydrodynamical…

Solar and Stellar Astrophysics · Physics 2017-11-15 Z. Keszthelyi , G. A. Wade , V. Petit

A-type stars have a complex internal structure with the possibility of multiple convection zones. If not sufficiently separated, such zones will interact through the convectively stable regions that lie between them. It is therefore of…

Astrophysics · Physics 2009-11-13 L. J. Silvers , M. R. E. Proctor

The topology and dynamics of the three-dimensional magnetic field in the solar atmosphere govern various solar eruptive phenomena and activities, such as flares, coronal mass ejections, and filaments/prominences. We have to observe and…

Solar and Stellar Astrophysics · Physics 2017-06-20 Yang Guo , Xin Cheng , M. D. Ding

The goal of this research is to investigate how magnetic field affects the dynamics of granular convection and excitation of solar oscillations by means of realistic numerical simulations. We have used a 3D, compressible, non-linear…

Astrophysics · Physics 2008-05-27 L. Jacoutot , A. G. Kosovichev , A. Wray , N. N. Mansour

We examine the impact of the magnetic field on Population III star formation by varying the magnetic field strength. We perform simulations with magnetic field strengths ranging from $10^{-20}$ G to $10^{-4}$ G, in addition to a model…

Solar and Stellar Astrophysics · Physics 2025-05-28 Masahiro N. Machida , Shingo Hirano , Shantanu Basu

The 3D thermal convection in the Boussinesq approximation with heating from below and dynamo in the cube are considered. We study dependence of the convection intensity and magnetic field generation on the latitude in $\beta$-plane…

Fluid Dynamics · Physics 2018-03-06 M. Yu. Reshetnyak

Magneto-convection simulations with two scenarios have been performed: In one, horizontal magnetic field is advected into the computational domain by fluid entering at the bottom. In the other, an initially uniform vertical magnetic field…

Astrophysics · Physics 2010-11-11 Robert F. Stein , David Bercik , Aake Nordlund

This talk summarizes results from recent MHD simulations of the role of a dipole magnetic field in inducing large-scale structure in the line-driven stellar winds of hot, luminous stars. Unlike previous fixed-field analyses, the MHD…

Astrophysics · Physics 2007-05-23 Asif ud-Doula , Stan Owocki

Subsurface convection zones are ubiquitous in early-type stars. Driven by narrow opacity peaks, these thin convective regions transport little heat but play an important role in setting the magnetic properties and surface variability of…

Solar and Stellar Astrophysics · Physics 2022-03-09 Adam S. Jermyn , Evan H. Anders , Matteo Cantiello

A fully three-dimensional computation of induction processes in a disk is performed to investigate the evolution of a large-scale magnetic field in gas-rich barred and spiral galaxies in the presence of field diffusion. As input parameters…

Astrophysics · Physics 2007-05-23 S. von Linden , K. Otmianowska-Mazur , H. Lesch , G. Skupniewicz

We investigate numerically magnetic field generation by thermal convection with square periodicity cells in a rotating horizontal layer of electrically-conducting fluid with stress-free electrically perfectly conducting boundaries for…

Chaotic Dynamics · Physics 2010-04-12 V. Zheligovsky

Convection is ubiquitous in stars and occurs under many different conditions. Here we explore convection in main-sequence stars through two lenses: dimensionless parameters arising from stellar structure and parameters which emerge from the…

Solar and Stellar Astrophysics · Physics 2022-08-31 Adam S. Jermyn , Evan H. Anders , Daniel Lecoanet , Matteo Cantiello

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

Magnetic fields have been detected in most if not all types of stars across the Hertzsprung-Russell diagram. Where present, these fields have the potential to significantly impact the evolution of their host stars. Furthermore, they…

Solar and Stellar Astrophysics · Physics 2017-12-21 A. J. Martin

Magnetic fields are hypothesized to inflate the radii of low-mass stars---defined as less massive than 0.8$M_\odot$---in detached eclipsing binaries (DEBs). We investigate this hypothesis using the recently introduced magnetic Dartmouth…

Solar and Stellar Astrophysics · Physics 2013-12-09 Gregory A. Feiden , Brian Chaboyer

Primordial magnetic fields could explain the large-scale magnetic fields present in the Universe. Inflation and phase transitions in the early Universe could give rise to such fields with unique characteristics. We investigate the…