Observational constraints for C-rich AGB stars

Author(s)
Gioia Rau, Josef Hron, Claudia Paladini, Bernhard Aringer, Paola Marigo, Kjell Eriksson
Abstract

We modeled the atmospheres of six carbon-rich Asymptotic Giant Branch stars (R Lep, R Vol, Y Pav, AQ Sgr, U Hya, and X TrA) using VLTI/MIDI interferometric observations, together with spectro-photometric data, we compared them with self-consistent, dynamic model atmospheres. The results show that the models can reproduce the Spectral Energy Distribution (SED) data well at wavelengths longer than 1 mu m, and the interferometric observations between 8 mu m and 10 mu m. We found differences at wavelengths shorter than 1 mu m in the SED, and longer than 10 mu m in the visibilities. The discrepancies observed can be explained in terms of a combination of data- and model-related reasons. We derived some stellar parameters, and our findings agree well with literature values within the uncertainties. Also, when comparing the location of the stars in the H-R diagram, with evolutionary tracks, the results show that the main derived properties (L, Teff, C/O ratios and stellar masses) from the model fitting are in good agreement with TP-AGB evolutionary calculations.

Organisation(s)
Department of Astrophysics
External organisation(s)
Université Libre de Bruxelles, Osservatorio Astronomico
Journal
Memorie Societa Astronomica Italiana
Volume
88
Pages
455-458
No. of pages
4
ISSN
0037-8720
Publication date
01-2017
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Portal url
https://ucrisportal.univie.ac.at/en/publications/6c0dce4f-fa78-4a95-9dff-fe6790776af2