To be or not to be Asymmetric? VLTI/MIDI and the Mass-loss Geometry of AGB Stars
- Author(s)
- Claudia Paladini, Daniela Klotz, Stephane Sacuto, Josef Hron, Franz Kerschbaum, Gioia Rau, Eric Lagadec, Markus Wittkowski, Andrea Richichi, Alain Jorissen, Martin A. T. Groenewegen, Tijl Verhoelst, Hans Olofsson, R. Zhao-Geisler, Alexis Matter
- Abstract
The Mid-infrared Interferometric instrument (MIDI) at the Very Large Telescope Interferometer (VLTI) has been used to spatially resolve the dust-forming region of 14 asymptotic giant branch (AGB) stars with different chemistry (O-rich and C-rich) and variability types (Miras, semi-regular, and irregular variables). The main goal of the programme was to detect deviations from spherical symmetry in the dust-forming region of these stars. All the stars of the sample are well resolved with the VLTI, and five are asymmetric and O-rich. This finding contrasts with observations in the near-infrared, where the C-rich objects are found to be more asymmetric than the O-rich ones. The nature of the asymmetric structures so far detected (dusty discs versus blobs)remains uncertain and will require imaging on milli-arcsecond scales.
- Organisation(s)
- Department of Astrophysics
- External organisation(s)
- Université Libre de Bruxelles, Uppsala University, Université Côte d'Azur, Royal Belgian Institute for Space Aeronomy, Chalmers University of Technology, European Southern Observatory (Germany), National Astronomical Research Institute of Thailand, Royal Observatory of Belgium, National Taiwan Normal University
- Journal
- The Messenger
- Volume
- 168
- Pages
- 28-31
- No. of pages
- 4
- ISSN
- 0722-6691
- DOI
- https://doi.org/10.18727/0722-6691/5022
- Publication date
- 06-2017
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103004 Astrophysics, 103003 Astronomy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/d9a6b08d-7795-4568-b11a-6d5105b5e8af