Modelling the atmosphere of the carbon-rich Mira RU Virginis

Autor(en)

Gioia Rau, Claudia Paladini, Josef Hron, Bernhard Aringer, Martin A. T. Groenewegen, Walter Nowotny-Schipper

Abstrakt

Context: We study the atmosphere of the carbon-rich Mira RU Vir using the mid-infrared high spatial resolution interferometric observations from VLTI/MIDI.
Aims: The aim of this work is to analyse the atmosphere of the carbon-rich Mira RU Vir with hydrostatic and dynamic models, in this way deepening the knowledge of the dynamic processes at work in carbon-rich Miras.
Methods: We compare spectro-photometric and interferometric measurements of this carbon-rich Mira AGB star with the predictions of different kinds of modelling approaches (hydrostatic model atmospheres plus MOD-More Of Dusty, self-consistent dynamic model atmospheres). A geometric model fitting tool is used for a first interpretation of the interferometric data.
Results: The results show that a joint use of different kinds of observations (photometry, spectroscopy, interferometry) is essential for shedding light on the structure of the atmosphere of a carbon-rich Mira. The dynamic model atmospheres fit the ISO spectrum well in the wavelength range λ = [2.9,25.0] μm. Nevertheless, a discrepancy is noticeable both in the SED (visible) and in the interferometric visibilities (shape and level), which is a possible explanation are intra-/inter-cycle variations in the dynamic model atmospheres, as well as in the observations. The presence of a companion star and/or a disk or a decrease in mass loss within the past few hundred years cannot be excluded, but these explanations are considered unlikely.
Based on observations made with ESO telescopes at La Silla Paranal Observatory under programme IDs: 085.D-0756 and 093. D-0708.Appendix A is available in electronic form at www.aanda.org

Organisation(en)

Institut für Astrophysik

Externe Organisation(en)

INAF - Osservatorio Astronomico di Padova, Royal Observatory of Belgium, Université Libre de Bruxelles

Journal

Astronomy & Astrophysics

Band

583

Anzahl der Seiten

14

ISSN

0004-6361

DOI

https://doi.org/10.1051/0004-6361/201526418

Publikationsdatum

11-2015

Peer-reviewed

Ja

ÖFOS 2012

103003 Astronomie, 103004 Astrophysik

Schlagwörter

ASJC Scopus Sachgebiete

Astronomy and Astrophysics, Space and Planetary Science

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/modelling-the-atmosphere-of-the-carbonrich-mira-ru-virginis(e8089797-738a-4e65-a331-4b788d17b76f).html