Resolved stellar populations of super-metal-rich star clusters in the bulge of M 31

Citation
P. Jablonka et al., Resolved stellar populations of super-metal-rich star clusters in the bulge of M 31, ASTRON ASTR, 359(1), 2000, pp. 131-137
Citations number
29
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY AND ASTROPHYSICS
ISSN journal
00046361 → ACNP
Volume
359
Issue
1
Year of publication
2000
Pages
131 - 137
Database
ISI
SICI code
0004-6361(200007)359:1<131:RSPOSS>2.0.ZU;2-0
Abstract
We have applied the MCS image deconvolution algorithm (Magain et al. 1998) to HST/WFPC2 V, I data of three M 31 bulge globular clusters (G170, G177, a nd G198) and control fields near each cluster. All three clusters are clear ly detected, with an increase in stellar density with decreasing radius fro m the cluster centers: this is the first time that stars have been resolved in bulge clusters in the inner regions of another galaxy. From the RGB slo pes of the clusters and the difference in I magnitude between the HE and th e top of the RGB, we conclude that these three clusters all have roughly so lar metallicity, in agreement with earlier integrated-light spectroscopic m easurements. Our data support a picture whereby the M 31 bulge clusters and field stars were born from the same metal-rich, gas, early in the galaxy f ormation.