Astronomy and Astrophysics – Astrophysics
Scientific paper
2006-12-20
Astron.J.133:1658-1672,2007
Astronomy and Astrophysics
Astrophysics
22 pages, 29 figures, accepted for publication in The Astronomical Journal, April 2007. High resolution version available at
Scientific paper
10.1086/511979
We present the first results of a large ACS Survey of Galactic globular clusters. This Hubble Space Telescope (HST) Treasury project is designed to obtain photometry with S/N > ~10 for main sequence stars with masses > ~0.2Msun in a sample of globulars using the Advanced Camera for Surveys (ACS) Wide Field Channel. Here we focus on clusters without previous HST imaging data. These include NGC 5466, 6779, 5053, 6144, Palomar 2, E 3, Lynga 7, Palomar 1, and NGC 6366. Our CMDs extend reliably from the horizontal branch to as much as seven magnitudes fainter than the main sequence turnoff and represent the deepest CMDs published to-date for these clusters. Using fiducial sequences for three standard clusters (M92, NGC 6752, and 47 Tuc) with well-known metallicities and distances, we perform main sequence fitting on the target clusters in order to obtain estimates of their distances and reddenings. These comparisons along with fitting the cluster main sequences to theoretical isochrones yield ages for the target clusters. We find that the majority of the clusters have ages that are consistent with the standard clusters at their metallicities. The exceptions are E 3 which appears ~2 Gyr younger than 47 Tuc, and Pal 1, which could be as much as 8 Gyr younger than 47 Tuc.
Anderson Jeffrey
Aparicio Antonio
Bedin Luciano
Chaboyer Brian
Dotter Aaron
No associations
LandOfFree
The ACS Survey of Galactic Globular Clusters. I. Overview and Clusters Without Previous HST Photometry does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The ACS Survey of Galactic Globular Clusters. I. Overview and Clusters Without Previous HST Photometry, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The ACS Survey of Galactic Globular Clusters. I. Overview and Clusters Without Previous HST Photometry will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-241527