Constraining convection across the AGB with high-angular-resolution observations

Author(s)
Claudia Paladini, Fabien Baron, A. Jorissen, J.-B. Le Bouquin, B. Freytag, Sophie Van Eck, M. Wittkowski, J. Hron, A. Chiavassa, J.-P. Berger, C. Siopis, A. Mayer, G. Sadowski, K. Kravchenko, S. Shetye, F. Kerschbaum, J. Kluska, S. Ramstedt
Abstract

We present very detailed images of the photosphere of an AGB star obtained with the PIONIER instrument, installed at the Very Large Telescope Interferometer (VLTI). The images show a well defined stellar disc populated by a few convective patterns. Thanks to the high precision of the observations we are able to derive the contrast and granulation horizontal scale of the convective pattern for the first time in a direct way. Such quantities are then compared with scaling relations between granule size, effective temperature, and surface gravity that are predicted by simulations of stellar surface convection.

Organisation(s)
Department of Astrophysics
External organisation(s)
European Southern Observatory (Chile), Georgia State University, Université Libre de Bruxelles, University of Grenoble Alpes, University of Michigan, Uppsala University, European Southern Observatory (Germany), Université Nice-Sophia-Antipolis, Katholieke Universiteit Leuven
Volume
14
Pages
27-30
No. of pages
4
DOI
https://doi.org/10.1017/S1743921318007378
Publication date
12-2019
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Keywords
ASJC Scopus subject areas
Astronomy and Astrophysics, Space and Planetary Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/001aa86f-d30e-4e1f-9fe1-621772b75371