An Old Cluster in NGC 6822

Details An Old Cluster in NGC 6822 An Old Cluster in NGC 6822

1998-03-04

arxiv.org/abs/astro-ph/9803041v1

Astronomy and Astrophysics

Astrophysics

8 pages; accepted for publication in AJ

Scientific paper

10.1086/300389

We present spectroscopy of two clusters in the dwarf irregular galaxy NGC 6822. From these we deduce an age for Cluster VII of 11 Gyr and [Fe/H] = -1.95 +/- 0.15 dex. Cluster VII appears to be an analog of the metal-poor galactic globular clusters. Cluster VI is found to be much younger and more metal rich, with an age of approximately 2 Gyr. Its derived metallicity, [Fe/H], of approximately -1.0 dex is comparable to that of the gas seen today in NGC 6822. The existence of a metal-poor old cluster in NGC 6822 rules out models for the chemical evolution of this galaxy with significant prompt initial enhancement. We find that a star formation rate which is constant with time and is within a factor of two of the present star formation rate can reproduce the two points on the age-metallicity relationship for NGC 6822 over the past 10 Gyr defined by these two clusters.

Affiliated with

Also associated with

No associations

Rating

An Old Cluster in NGC 6822 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 An Old Cluster in NGC 6822, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An Old Cluster in NGC 6822 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-679508