The AGB population of NGC 6822

التفاصيل البيبلوغرافية
العنوان: The AGB population of NGC 6822
المؤلفون: Sibbons, L. F., Cioni, M. -R. L., Irwin, M., Rejkuba, M.
سنة النشر: 2010
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Solar and Stellar Astrophysics
الوصف: The metallicity gradient and the stellar distribution within the Local Group dwarf galaxy NGC 6822 has been studied photometrically using asymptotic branch stars (AGB). In order to study the stellar and metallicity distribution, the carbon- and oxygen-rich AGB stars have been isolated using deep high-quality near-infrared UKIRT photometry. The ratio between them, the C/M ratio, has been used to derive the [Fe/H] abundance within the galaxy. The [Fe/H] abundance and stellar distribution were analysed as a function of galactic radius. A mean C/M ratio of 0.288 +/- 0.014 has been found which corresponds to an iron abundance of [Fe/H] =-1.14 +/-0.08 dex, with variations in the north and south, as well as at larger galactocentric distances. Variations in the magnitude of the tip of the red giant branch has also been detected.
Comment: Conference proceedings, Vienna 2010, 'Why Galaxies care about AGB stars? II'
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/1011.4464
رقم الأكسشن: edsarx.1011.4464
قاعدة البيانات: arXiv