Investigating the Properties of Granulation in the Red Giants Observed by Kepler
- Author(s)
- S. Mathur, S. Hekker, R. Trampedach, J. Ballot, T. Kallinger, D. Buzasi, R. A. García, D. Huber, A. Jiménez, B. Mosser, T. R. Bedding, Y. Elsworth, C. Régulo, D. Stello, W. J. Chaplin, J. De Ridder, S. J. Hale, K. Kinemuchi, H. Kjeldsen, F. Mullally, S. E. Thompson
- Abstract
More than 1000 red giants have been observed by NASA/Kepler missionduring a nearly continuous period of ˜ 13 months. The resultinghigh-frequency resolution (<0.03 μHz) allows us to study thegranulation parameters of these stars. The granulation pattern resultsfrom the convection motions leading to upward flows of hot plasma anddownward flows of cooler plasma. We fitted Harvey-like functions to thepower spectra, to retrieve the timescale and amplitude of granulation.We show that there is an anti-correlation between both of theseparameters and the position of maximum power of acoustic modes, while wealso find a correlation with the radius, which agrees with the theory.We finally compare our results with 3D models of the convection.
- Organisation(s)
- Department of Astrophysics
- External organisation(s)
- National Center for Atmospheric Research (NCAR), University of Amsterdam (UvA), University of Birmingham, University of Colorado, Boulder, University of Toulouse, Katholieke Universiteit Leuven, Eureka Scientific Inc., Université Paris VII - Paris-Diderot, The University of Sydney, University of La Laguna, Université de recherche Paris Sciences et Lettres, National Aeronautics & Space Administration (NASA), Aarhus University
- Journal
- Astronomical Society of the Pacific Conference Series
- Volume
- 462
- Pages
- 375
- ISSN
- 1050-3390
- Publication date
- 09-2012
- Austrian Fields of Science 2012
- 103004 Astrophysics
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/306906a5-752d-4ccb-ac16-e3866c223b17