English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Dynamo cycles in global convection simulations of solar-like stars

Warnecke, J. (2018). Dynamo cycles in global convection simulations of solar-like stars. Astronomy and Astrophysics, 616: A72. doi:10.1051/0004-6361/201732413.

Item is

Basic

show hide
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Warnecke, Jörn1, 2, Author              
Affiliations:
1Department Sun and Heliosphere, Max Planck Institute for Solar System Research, Max Planck Society, ou_1832287              
2Max Planck Research Group in Solar and Stellar Magnetic Activity (Mag Activity) – SOLSTAR, Max Planck Institute for Solar System Research, Max Planck Society, Justus-von-Liebig-Weg 3, 37077 Göttingen, DE, ou_2265638              

Content

show
hide
Free keywords: magnetohydrodynamics / turbulence / dynamo / Sun: magnetic fields / stars: activity / stars: magnetic field
 Abstract: Context. Several solar-like stars exhibit cyclic magnetic activity similar to the Sun as found in photospheric and chromospheric emission. Aims. We seek to understand the physical mechanism involved in rotational dependence of these activity cycle periods. Methods. We used three-dimensional magnetohydrodynamical simulations of global convective dynamos models of solar-like stars to investigate the rotational dependency of dynamos. We further applied the test-field method to determine the α effect in these simulations. Results. We find dynamos with clear oscillating mean magnetic fields for moderately and rapidly rotating runs. For slower rotation, the field is constant or exhibit irregular cycles. In the moderately and rapidly rotating regime the cycle periods increase weakly with rotation. This behavior can be well explained with a Parker–Yoshimura dynamo wave traveling equatorward. Even though the α effect becomes stronger for increasing rotation, the shear decreases more steeply, causing this weak dependence on rotation. Similar to other numerical studies, we find no indication of activity branches that have been postulated in former observational studies. However, our simulations seem to agree more with the transitional branch suggested by more recent observational studies. If the Sun exhibited a dynamo wave similar to that which we find in our simulations, it would operate deep inside the convection zone.

Details

show
hide
Language(s): eng - English
 Dates: 2018
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1051/0004-6361/201732413
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Astronomy and Astrophysics
  Other : Astron. Astrophys.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Les Ulis Cedex A France : EDP Sciences
Pages: - Volume / Issue: 616 Sequence Number: A72 Start / End Page: - Identifier: Other: 1432-0746
ISSN: 0004-6361
CoNE: https://pure.mpg.de/cone/journals/resource/954922828219_1