St Andrews Research Repository

St Andrews University Home
View Item 
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  • Login
JavaScript is disabled for your browser. Some features of this site may not work without it.

The energy budget of stellar magnetic fields

Thumbnail
View/Open
Vidotto_2015_MNRAS_Energy.pdf (700.9Kb)
Date
11/11/2015
Author
See, Wyke Chun Victor
Jardine, Moira Mary
Vidotto, Aline
Donati, J.-F.
Folsom, C. P.
Boro Saikia, S.
Bouvier, J.
Fares, Rim
Gregory, Scott
Hussain, Gaitee Ara Jaffer
Jeffers, Sandra Victoria
Marsden, S. C.
Morin, J.
Moutou, C.
do Nascimento, J. D.
Petit, P.
Rosén, L.
Waite, I. A.
Funder
Science & Technology Facilities Council
Science & Technology Facilities Council
Science & Technology Facilities Council
Grant ID
ST/J001651/1
ST/J003255/1
ST/M001296/1
Keywords
Techniques: polarimetric
Stars: activity
Stars: magnetic field
Stars: rotation
QB Astronomy
QC Physics
3rd-DAS
Metadata
Show full item record
Altmetrics Handle Statistics
Altmetrics DOI Statistics
Abstract
Spectropolarimetric observations have been used to map stellar magnetic fields, many of which display strong bands of azimuthal fields that are toroidal. A number of explanations have been proposed to explain how such fields might be generated though none are definitive. In this paper, we examine the toroidal fields of a sample of 55 stars with magnetic maps, with masses in the range 0.1–1.5 M⊙. We find that the energy contained in toroidal fields has a power-law dependence on the energy contained in poloidal fields. However the power index is not constant across our sample, with stars less and more massive than 0.5 M⊙ having power indices of 0.72 ± 0.08 and 1.25 ± 0.06, respectively. There is some evidence that these two power laws correspond to stars in the saturated and unsaturated regimes of the rotation-activity relation. Additionally, our sample shows that strong toroidal fields must be generated axisymmetrically. The latitudes at which these bands appear depend on the stellar rotation period with fast rotators displaying higher latitude bands than slow rotators. The results in this paper present new constraints for future dynamo studies.
Citation
See , W C V , Jardine , M M , Vidotto , A , Donati , J-F , Folsom , C P , Boro Saikia , S , Bouvier , J , Fares , R , Gregory , S , Hussain , G A J , Jeffers , S V , Marsden , S C , Morin , J , Moutou , C , do Nascimento , J D , Petit , P , Rosén , L & Waite , I A 2015 , ' The energy budget of stellar magnetic fields ' , Monthly Notices of the Royal Astronomical Society , vol. 453 , no. 4 , pp. 4301-4310 . https://doi.org/10.1093/mnras/stv1925
Publication
Monthly Notices of the Royal Astronomical Society
Status
Peer reviewed
DOI
https://doi.org/10.1093/mnras/stv1925
ISSN
0035-8711
Type
Journal article
Rights
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society, © 2015 The Authors, Published by Oxford University Press on behalf of the Royal Astronomical Society. This work is made available online in accordance with the publisher’s policies. This is the final published version of the work, which was originally published at https://dx.doi.org/10.1093/mnras/stv1925
Description
VS acknowledges the support of an Science & Technology Facilities Council (STFC) studentship. AAV acknowledges support from the Swiss National Science Foundation through an Ambizione Fellowship. SBS and SVJ acknowledge research funding by the Deutsche Forchungsgemeinschaft (DFG) under grant SFB, project A16. SGG acknowledges support from the STFC via an Ernest Rutherford Fellowship [ST/J003255/1]. This study was supported by the grant ANR 2011 Blanc SIMI5-6 020 01 ‘Toupies: Towards understanding the spin evolution of stars’ (http://ipag.osug.fr/Anr_Toupies/).
Collections
  • University of St Andrews Research
URL
http://adsabs.harvard.edu/abs/2015MNRAS.453.4301S
URI
http://hdl.handle.net/10023/7737

Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

Advanced Search

Browse

All of RepositoryCommunities & CollectionsBy Issue DateNamesTitlesSubjectsClassificationTypeFunderThis CollectionBy Issue DateNamesTitlesSubjectsClassificationTypeFunder

My Account

Login

Open Access

To find out how you can benefit from open access to research, see our library web pages and Open Access blog. For open access help contact: openaccess@st-andrews.ac.uk.

Accessibility

Read our Accessibility statement.

How to submit research papers

The full text of research papers can be submitted to the repository via Pure, the University's research information system. For help see our guide: How to deposit in Pure.

Electronic thesis deposit

Help with deposit.

Repository help

For repository help contact: Digital-Repository@st-andrews.ac.uk.

Give Feedback

Cookie policy

This site may use cookies. Please see Terms and Conditions.

Usage statistics

COUNTER-compliant statistics on downloads from the repository are available from the IRUS-UK Service. Contact us for information.

© University of St Andrews Library

University of St Andrews is a charity registered in Scotland, No SC013532.

  • Facebook
  • Twitter