Astronomy and Astrophysics – Astronomy
Scientific paper
Mar 1995
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995aj....109.1019s&link_type=abstract
Astronomical Journal (ISSN 0004-6256), vol. 109, no. 3, p. 1019-1032
Astronomy and Astrophysics
Astronomy
49
Abundance, Galactic Halos, Globular Clusters, Metallicity, Star Formation, Stellar Color, Stellar Composition, Stellar Luminosity, Color-Magnitude Diagram, Data Reduction, Spatial Distribution, Stellar Spectrophotometry
Scientific paper
We have obtained metal abundances from Washington photometry (C, T1) for a large sample of globular clusters around NGC 3311, the central cD in the Hydra I (A1060) galaxy cluster. Our spatial coverage extends out to a galactocentric radius approximately 2.2 arcmin (about 30 kpc for H0 = 75). Analysis of the metallicity distribution function (MDF) reveals a median metallicity of (Fe/H)C-T1 = -0.31 with a dispersion of 0.35 dex; the MDF is skewed, with a small but definite low-metallicity tail extending down to (Fe/H)C-T1 approximately -1.8 dex. It may also be bimodal, with significant peaks near (Fe/H)C-T1 = -0.5 and 0.15 dex. We estimate that 30 percent of the clusters exceed solar abundance, based upon a linear extrapolation of the galactic calibrating relation between (c-T(sub1))0 and (Fe/H)C-T1. Perhaps most notably, the population of clusters near (Fe/H)C-T1 approximately -1 that dominates the MDF in order giant E galaxies is almost totally missing in NGC 3311 making it the most metal-rich system known. Finally, we find a significant radial gradient in mean metallicity, Delta (Fe/H)C-T1/ Delta (log Rgc = -0.78+/-0.60. It is suggested that virtually all the protostellar gas in this cD galaxy went through a considerable amount of pre-enrichment everywhere in the halo, before almost any stars or clusters formed. These data provide a strong challenge to any model which requires low metallicity for globular cluster formation.
Geisler Doug
Harris William E.
McLaughlin Dean E.
Secker Jeff
No associations
LandOfFree
Washington photometry of the globular cluster system around NGC 3311. 1: Analysis of the metallicities 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 Washington photometry of the globular cluster system around NGC 3311. 1: Analysis of the metallicities, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Washington photometry of the globular cluster system around NGC 3311. 1: Analysis of the metallicities will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-883859