The field population towards the globular cluster NGC 6553

Citation
A. Vallenari et S. Ortolani, The field population towards the globular cluster NGC 6553, ASTRON ASTR, 380(2), 2001, pp. L35-L38
Citations number
18
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY & ASTROPHYSICS
ISSN journal
14320746 → ACNP
Volume
380
Issue
2
Year of publication
2001
Pages
L35 - L38
Database
ISI
SICI code
1432-0746(200112)380:2<L35:TFPTTG>2.0.ZU;2-0
Abstract
We analyze the colour magnitude diagram of the field population in the dire ction of the bulge cluster NGC 6553 to discuss the stellar field component projected towards the cluster. In particular we investigate the nature of a peculiar feature, called "red flare" which appears as a faint turnoff, loc ated 2 mag about below the turnoff of the cluster, with a sparse trace of a sub-giant branch just above. A detailed modeling shows that the red are is consistent with the expected location of the turnoff and sub-giant branch of the bulge population, once that the appropriate metallicity range and sp atial distribution of the bulge stars are adopted. From the data, hints can be derived about the spatial shape and the basic stellar parameters of the bulge.