Galactic distributions of carbon- and oxygen-rich AGB stars revealed by the AKARI mid-infrared all-sky survey

Ishihara, D., Kaneda, H., Onaka, T., Matsuura, M. ORCID: https://orcid.org/0000-0002-5529-5593 and Matsunaga, N. 2011. Galactic distributions of carbon- and oxygen-rich AGB stars revealed by the AKARI mid-infrared all-sky survey. Astronomy & Astrophysics 534 , A79. 10.1051/0004-6361/201117626

Full text not available from this repository.

Abstract

Context. The environmental conditions for asympotic giant branch (AGB) stars to reach the carbon-rich (C-rich) phase are important to understand the evolutionary process of AGB stars. The difference between the spatial distributions of C-rich and oxygen-rich (O-rich) AGB stars is essential for the study of the Galactic structure and the chemical evolution of the interstellar medium. Aims: We quantitatively investigate the spatial distributions of C-rich and O-rich AGB stars in our Galaxy. We discuss the difference between them and its origin. Methods: We classify a large number of AGB stars newly detected by the AKARI mid-infrared all-sky survey. In the color-color diagrams, we define their occupation zones based on the locations of known objects. We then obtain the spatial distributions of C-rich and O-rich AGB stars, assuming that they have the same luminosity for a given mass-loss rate. Results: We find that O-rich AGB stars are concentrated toward the Galactic center and that the density decreases with Galactocentric distance, whereas C-rich AGB stars show a relatively uniform distribution within about 8 kpc of Sun. Conclusions: Our result confirms the trends reported in previous studies and extends them to a Galactic scale. We discuss the relations between our result, the Galactic metallicity gradient, and the chemical evolution of the ISM in our Galaxy....

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Physics and Astronomy
Publisher:	EDP Sciences
ISSN:	0004-6361
Date of Acceptance:	5 August 2011
Last Modified:	14 May 2024 16:00
URI:	https://orca.cardiff.ac.uk/id/eprint/168057

Actions (repository staff only)

Edit Item