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On the Iron content of NGC 1978 in the LMC: a metal rich, chemically homogeneous cluster

Francesco R. Ferraro·Alessio Mucciarelli·Eugenio Carretta·Livia Origlia
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Abstract

We present a detailed abundance analysis of giant stars in NGC 1978, a massive, intermediate-age stellar cluster in the Large Magellanic Cloud, characterized by a high ellipticity and suspected to have a metallicity spread. We analyzed 11 giants, all cluster members, by using high resolution spectra acquired with the UVES/FLAMES spectrograph at the ESO-Very Large Telescope. We find an iron content of [Fe/H]=-0.38 dex with very low (0.07 dex) dispersion, and a mean heliocentric radial velocity Vr=293.1 (with an error of 0.9 km/s) and a velocity dispersion (3.1 km/s), thus excluding the presence of a significant metallicity, as well as velocity, spread within the cluster.

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Francesco R. Ferraro, Alessio Mucciarelli, Eugenio Carretta, Livia Origlia. 2006-05-25. On the Iron content of NGC 1978 in the LMC: a metal rich, chemically homogeneous cluster. https://doi.org/10.1086/506178

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