Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-18T09:59:06.512Z Has data issue: false hasContentIssue false

Magnetic field generation in PMS stars with and without radiative core

Published online by Cambridge University Press:  12 September 2017

B. Zaire*
Affiliation:
Physics Department, Universidade Federal de Minas Gerais Belo Horizonte, MG 31270-901, Brazil
G. Guerrero*
Affiliation:
Physics Department, Universidade Federal de Minas Gerais Belo Horizonte, MG 31270-901, Brazil
A. G. Kosovichev
Affiliation:
New Jersey Institute of Technology Newark, NJ 07103, USA
P. K. Smolarkiewicz
Affiliation:
European Centre for Medium-Range Weather ForecastsReading RG2 9AX, UK
N. R. Landin
Affiliation:
Campus UFV Florestal, Universidade Federal de Viosa Florestal, MG 35690-000, Brazil
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.

Recent observations of the magnetic field in pre-main sequence stars suggest that the magnetic field topology changes as a function of age. The presence of a tachocline could be an important factor in the development of magnetic field with higher multipolar modes. In this work we performed MHD simulations using the EULAG-MHD code to study the magnetic field generation and evolution in models that mimic stars at two evolutionary stages. The stratification for both stellar phases was computed by fitting stellar structure profiles obtained with the ATON stellar evolution code. The first stage is at 1.1Myr, when the star is completely convective. The second stage is at 14Myrs, when the star is partly convective, with a radiative core developed up to 30% of the stellar radius. In this proceedings we present a preliminary analysis of the resulting mean-flows and magnetic field. The mean-flow analysis shown that the star rotate almost rigidly on the fully convective phase, whereas at the partially convective phase there is differential rotation with conical contours of iso-rotation. As for the mean magnetic field both simulations show similarities with respect to the field evolution. However, the topology of the magnetic field is different.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2017 

References

Browning, M. K., 2008, The Astrophysical Journal, 676, 1262 CrossRefGoogle Scholar
Bessolaz, N. & Brun, A., 2011, Astronomische Nachrichten, 332, 1045 CrossRefGoogle Scholar
Donati, J.-F., Mengel, M., Carter, B. D., et al., 2000, Monthly Notices of the Royal Astronomical Society, 316, 3 CrossRefGoogle Scholar
Donati, J.-F., Jardine, M., Gregory, S., et al., 2007, Monthly Notices of the Royal Astronomical Society, 380, 1297 Google Scholar
Donati, J.-F., Jardine, M., Gregory, S., et al., 2008, Monthly Notices of the Royal Astronomical Society, 386, 1234 CrossRefGoogle Scholar
Donati, J.-F., Skelly, M., Bouvier, J., et al., 2010, Monthly Notices of the Royal Astronomical Society, 402, 1426 Google Scholar
Donati, J.-F., Bouvier, J., Walter, F., et al., 2011, Monthly Notices of the Royal Astronomical Society, 412, 2454 CrossRefGoogle Scholar
Donati, J.-F., Gregory, S., Alencar, S., et al., 2012, Monthly Notices of the Royal Astronomical Society, 425, 2948 CrossRefGoogle Scholar
Gallet, F. & Bouvier, J., 2013, Astronomy & Astrophysics, 556, A36 Google Scholar
Gastine, T., Duarte, L., & Wicht, J., 2012, Astronomy & Astrophysics, 546, A19 Google Scholar
Ghizaru, M., Charbonneau, P., & Smolarkiewicz, P. K., 2010, The Astrophysical Journal Letters, 715, L133 Google Scholar
Gregory, S. G., Donati, J.-F., Morin, J., et al., 2012, The Astrophysical Journal, 755, 97 CrossRefGoogle Scholar
Guerrero, G., Smolarkiewicz, P. K., Kosovichev, A. G., & Mansour, N. N., 2013, The Astrophysical Journal, 779, 176 CrossRefGoogle Scholar
Guerrero, G. and Smolarkiewicz, P. K. and de Gouveia Dal Pino, E. M., & Kosovichev, A. G. and Mansour, N. N., 2016, The Astrophysical Journal Letters, 828, L3 CrossRefGoogle Scholar
Guerrero, G., Smolarkiewicz, P. K., de Gouveia Dal Pino, M., Kosovichev, A. G., & Mansour, N. N., 2016, The Astrophysical Journal, 819, 104 CrossRefGoogle Scholar
Johns-Krull, C. M., 1996, Astronomy and Astrophysics, 306, 803 Google Scholar
Landin, N. R., Ventura, P., D’Antona, F., Mendes, L. T. S., & Vaz, L. P. R., 2006, Astronomy & Astrophysics, 456, 269 Google Scholar
Prusa, J. M., Smolarkiewicz, P. K., & Wyszogrodzki, A. A., 2008, Comput. Fluids, 37, 1193 Google Scholar
Racine, É., Charbonneau, P., Ghizaru, M., Bouchat, A., & Smolarkiewicz, P. K., 2011, The Astrophysical Journal, 735, 46 Google Scholar
Smolarkiewicz, P. K. & Charbonneau, P., 2013, J. Comput. Phys., 236, 608 Google Scholar
Vidotto, A., Gregory, S., Jardine, M., et al., 2014, Monthly Notices of the Royal Astronomical Society, 441, 2361 Google Scholar
Yadav, R. K., Christensen, U. R., Morin, J., et al., 2015, The Astrophysical Journal Letters, 813, L31 Google Scholar