RT Journal Article
T1 Magnetic fields in M dwarfs from the CARMENES survey
A1 Cortés Contreras, Miriam
A1 Montes Gutiérrez, David
AB Context. M dwarfs are known to generate the strongest magnetic fields among main-sequence stars with convective envelopes, but we are still lacking a consistent picture of the link between the magnetic fields and underlying dynamo mechanisms, rotation, and activity.Aims. In this work we aim to measure magnetic fields from the high-resolution near-infrared spectra taken with the CARMENES radial-velocity planet survey in a sample of 29 active M dwarfs and compare our results against stellar parameters.Methods. We used the state-of-the-art radiative transfer code to measure total magnetic flux densities from the Zeeman broadening of spectral lines and filling factors.Results. We detect strong kG magnetic fields in all our targets. In 16 stars the magnetic fields were measured for the first time. Our measurements are consistent with the magnetic field saturation in stars with rotation periods P < 4 d. The analysis of the magnetic filling factors reveal two different patterns of either very smooth distribution or a more patchy one, which can be connected to the dynamo state of the stars and/or stellar mass. Conclusions. Our measurements extend the list of M dwarfs with strong surface magnetic fields. They also allow us to better constrain the interplay between the magnetic energy, stellar rotation, and underlying dynamo action. The high spectral resolution and observations at near-infrared wavelengths are the beneficial capabilities of the CARMENES instrument that allow us to address important questions about the stellar magnetism.
PB EDP Sciences S A
SN 1432-0746
YR 2019
FD 2019-06
LK https://hdl.handle.net/20.500.14352/13570
UL https://hdl.handle.net/20.500.14352/13570
LA eng
NO © D. Shulyak et al. 2019. Artículo firmado por 24 autores. CARMENES is an instrument for the Centro Astronómico Hispano-Alemán de Calar Alto (CAHA, Almeria, Spain). CARMENES is funded by the German Max-Planck-Gesellschaft (MPG), the Spanish Consejo Superior de Investigaciones Cientificas (CSIC), the European Union through FEDER/ERF FICTS-2011-02 funds, and the members of the CARMENES Consortium (Max-Planck-Institut für Astronomie, Instituto de Astrofisica de Andalucia, Landessternwarte Königstuhl, Institut de Ciéncies de l’Espai, Insitut für Astrophysik Göttingen, Universidad Complutense de Madrid, Thüringer Landessternwarte Tautenburg, Instituto de Astrofisica de Canarias, Hamburger Sternwarte, Centro de Astrobiologia and Centro Astronómico Hispano-Alemán), with additional contributions by the Spanish Ministry of Economy, the German Science Foundation through the Major Research Instrumentation Programme and DFG Research Unit FOR2544 “Blue Planets around Red Stars”, the Klaus Tschira Stiftung, the states of Baden-Württemberg and Niedersachsen, and by the Junta de Andalucia. L.T.-O. acknowledges support from the Israel Science Foundation (grant No. 848/16). This work has made use of the VALD database, operated at Uppsala University, the Institute of Astronomy RAS in Moscow, and the University of Vienna. We also acknowledge the use of electronic database.
NO FEDER/ERF FICTS-2011-02
NO German Max-Planck-Gesellschaft (MPG)
NO Consejo Superior de Investigaciones Cientificas (CSIC)
NO Max-Planck-Institut für Astronomie
NO Instituto de Astrofísica de Andalucía
NO Landessternwarte Königstuhl
NO Institut de Ciéncies de l’Espai
NO Insitut für Astrophysik Göttingen
NO Universidad Complutense de Madrid
NO Thüringer Landessternwarte Tautenburg
NO Instituto de Astrofísica de Canarias
NO Hamburger Sternwarte
NO Centro de Astrobiología and Centro Astronómico Hispano-Alemán
NO Spanish Ministry of Economy
NO the German Science Foundation through the Major Research Instrumentation Programme
NO DFG Research Unit FOR2544 “Blue Planets around Red Stars”
NO Klaus Tschira Stiftung
NO the states of Baden-Württemberg and Niedersachsen
NO Junta de Andalucía
NO Israel Science Foundation
DS Docta Complutense
RD 22 abr 2025