A spectroscopic study of the Globular Cluster NGC 4147

Abstract

We present the abundance analysis for a sample of 18 red giant branch stars in the metal-poor globular cluster NGC 4147 based on medium and high resolution spectra. This is the first extensive spectroscopic study of this cluster. We derive abundances of C, N, O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Y, Ba, and Eu. We find a metallicity of [Fe/H]=-1.84+-0.02 and an alpha-enhancement of +0.38+-0.05 (errors on the mean), typical of halo globular clusters in this metallicity regime. A significant spread is observed in the abundances of light elements C, N, O, Na, and Al. In particular we found a Na-O anti-correlation and Na-Al correlation. The cluster contains only 15% of stars that belong to the first generation (Na-poor and O-rich). This implies that it suffered a severe mass loss during its lifetime. Its [Ca/Fe] and [Ti/Fe] mean values agree better with the Galactic Halo trend than with the trend of extragalactic environments at the cluster metallicity. This possibly suggests that NGC 4147 is a genuine Galactic object at odd with what claimed by some author that proposed the cluster to be member of the Sagittarius dwarf galaxy. A anti-relation between the light s-process element Y and Na may also be present.

10 pages, 12 figures, accepted for publication on MNRAS

References in corpus (10)

• Formation and Dynamical Evolution of Multiple Stellar Generations in Globular Clusters
• Spectroscopic and Photometric evidence of two stellar populations in the Galactic Globular Cluster NGC6121 (M4)
• First Stars VIII -- Enrichment of the neutron-capture elements in the early Galaxy
• Evolution, nucleosynthesis and yields of AGB stars at different metallicities (III): intermediate mass models, revised low mass models and the ph-FRUITY interface
• The exotic chemical composition of the Sagittarius dwarf Spheroidal galaxy
• The Highly Unusual Chemical Composition of the Hercules Dwarf Spheroidal Galaxy
• Looking outside the Galaxy: the discovery of chemical anomalies in 3 old Large Magellanic Cloud clusters
• The chemical composition of red giant stars in four intermediate-age clusters of the Large Magellanic Cloud
• Chemical abundances of giant stars in NGC 5053 and NGC 5634, two globular clusters associated with the Sagittarius dwarf Spheroidal galaxy?
• Dynamical Constraints on the Origin of Multiple Stellar Populations in Globular Clusters

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