Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-25T17:10:19.839Z Has data issue: false hasContentIssue false

Magnetic fields in M-dwarfs from high-resolution infrared spectroscopy

Published online by Cambridge University Press:  07 August 2014

D. Shulyak
Affiliation:
Institute of Astrophysics, Georg-August University, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
A. Reiners
Affiliation:
Institute of Astrophysics, Georg-August University, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
U. Seemann
Affiliation:
Institute of Astrophysics, Georg-August University, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
O. Kochukhov
Affiliation:
Department of Physics and Astronomy, Uppsala University, Box 515, 751 20, Uppsala, Sweden
N. Piskunov
Affiliation:
Department of Physics and Astronomy, Uppsala University, Box 515, 751 20, Uppsala, Sweden
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Accurate spectroscopic measurements of magnetic fields in low mass stars remain challenging because of their cool temperatures, strong line blending, and often fast rotation. This is why previous estimates were based either on the analysis of only a few lines or made use of some indirect techniques. This frequently led to noticeable scatter in obtained results. In this talk I will present and discuss new results on the determination of the intensity and geometry of the magnetic fields in M-dwarfs using IR observations obtained with CRIRES@VLT. The instrument provides unprecedented data of high resolution (R = 100 000) which is crucial for resolving individual magnetically broadened molecular and atomic lines. Such an in-depth analysis based on direct magnetic spectral synthesis opens a possibility to deduce both field intensity and geometry avoiding most of the limitation and assumptions made in previous studies.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2014 

References

Afram, N., Berdyugina, S. V., Fluri, D. M., Solanki, S. K., & Lagg, A. 2008, A&A, 482, 387Google Scholar
Asensio Ramos, A. & Trujillo Bueno, J. 2006, ApJ, 636, 548Google Scholar
Berdyugina, S. V. & Solanki, S. K. 2002, A&A, 385, 701Google Scholar
Crozet, P., Tourasse, G., Ross, A., Paletou, F. & López Ariste, A. 2012, EAS Publications Series, 58, 63Google Scholar
Johns-Krull, C. M. & Valenti, J. A. 2000, Stellar Clusters and Associations: Convection, Rotation, and Dynamos, 198, 371Google Scholar
Johns-Krull, C. M. & Valenti, J. A. 1996, ApJ, 459, L95Google Scholar
Harrison, J. J. & Brown, J. M. 2008, ApJ, 686, 1426CrossRefGoogle Scholar
Kochukhov, O., Heiter, U., Piskunov, N., et al. 2009, 15 th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, 1094, 124CrossRefGoogle Scholar
Leroy, B. 2004, Molecular Zeeman Library Reference Manual (avalaible on-line at http://bass2000.obspm.fr/mzl/download/mzl-ref.pdf)Google Scholar
Morin, J., Donati, J.-F., Petit, P., et al. 2010, MNRAS, 407, 2269CrossRefGoogle Scholar
Reiners, A. 2012, Living Reviews in Solar Physics, 9, 1Google Scholar
Reiners, A., Basri, G., & Browning, M. 2009, ApJ, 692, 538CrossRefGoogle Scholar
Reiners, A. & Basri, G. 2007, ApJ, 656, 1121CrossRefGoogle Scholar
Reiners, A. & Basri, G. 2006, ApJ, 644, 497Google Scholar
Shulyak, D., Reiners, A., Seemann, U., Kochukhov, O., & Piskunov, N. 2013, A&A, submittedGoogle Scholar
Saar, S. H. & Linsky, J. L. 1985, ApJ, 299, L47Google Scholar
Shulyak, D., Reiners, A., Wende, S., et al. 2010, A&A, 523, A37Google Scholar
Valenti, J. A., Johns-Krull, C. M., & Piskunov, N. E. 2001, 11th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun, 223, 1579Google Scholar