METHODS: DATA ANALYSIS; GALAXIES: FORMATION; GALAXIES: INDIVIDUAL: M 31; GALAXIES: SPIRAL; GALAXIES: STAR CLUSTERS; GALAXIES: STELLAR CONTENT
Abstract :
[en] 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, and G198) and control fields near each cluster. All three clusters are clearly detected, with an increase in stellar density with decreasing radius from 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 slopes of the clusters and the difference in I magnitude between the HB and the top of the RGB, we conclude that these three clusters all have roughly solar metallicity, in agreement with earlier integrated-light spectroscopic measurements. 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 formation.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Jablonka, P.; DAEC-URA 8631, Observatoire de Paris-Meudon, Place Jules Janssen, 92195 Meudon, France
Courbin, F.; Universidad Católica de Chile, Departamento de Astronomía y Astrofísica, Av. Vicuña Mackena 4860, Casilla 306, Santiago 22, Chile
Meylan, G.; European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching, Germany
Sarajedini, A.; Astronomy Department, Wesleyan University, Middletown, CT 06459, USA
Bridges, T. J.; Anglo- Australian Observatory, P.O. Box 296, Epping, NSW, 1710, Australia
Magain, Pierre ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique et traitement de l'image
Language :
English
Title :
Resolved stellar populations of super-metal-rich star clusters in the bulge of M 31
