Volume 509, January 2010
|Number of page(s)||11|
|Section||Stellar structure and evolution|
|Published online||14 January 2010|
Exploring the P vs. P relation with flux transport dynamo models of solar-like stars
Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot,
IRFU/SAp, 91191 Gif-sur-Yvette, France e-mail: firstname.lastname@example.org
2 D.A.M.T.P., Centre for Mathematical Sciences, University of Cambridge, Cambridge CB03 0WA, UK
3 JILA and Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309-0440, USA
Accepted: 5 November 2009
Aims. Understand stellar magnetism and test the validity of the Babcock-Leighton flux transport mean field dynamo models with stellar activity observations
Methods. 2-D mean field dynamo models at various rotation rates are computed with the STELEM code to study the sensitivity of the activity cycle period and butterfly diagram to parameter changes and are compared to observational data. The novelty is that these 2-D mean field dynamo models incorporate scaling laws deduced from 3-D hydrodynamical simulations for the influence of rotation rate on the amplitude and profile of the meridional circulation. These models make also use of observational scaling laws for the variation of differential rotation with rotation rate.
Results. We find that Babcock-Leighton flux transport dynamo models are able to reproduce the change in topology of the magnetic field (i.e. toward being more toroidal with increasing rotation rate) but seem to have difficulty reproducing the cycle period vs activity period correlation observed in solar-like stars if a monolithic single cell meridional flow is assumed. It may however be possible to recover the vs. relation with more complex meridional flows, if the profile changes in a particular assumed manner with rotation rate.
Conclusions. The Babcock-Leighton flux transport dynamo model based on single cell meridional circulation does not reproduce the vs. relation unless the amplitude of the meridional circulation is assumed to increase with rotation rate which seems to be in contradiction with recent results obtained with 3-D global simulations.
Key words: magnetohydrodynamics / stars: activity / stars: magnetic fields / Sun: activity / methods: numerical
© ESO, 2010
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.