Comprehensive abundance analysis of red giants in the open clusters NGC 752, NGC 1817, NGC 2360 and NGC 2506

TL;DR

This study conducts a detailed chemical abundance analysis of red giants in four open clusters using high-resolution spectra, revealing that their elemental compositions are consistent with those of thin disk field stars, supporting the cluster disruption hypothesis.

Contribution

It provides precise abundance measurements for multiple elements in red giants across four open clusters, demonstrating their similarity to field stars and supporting cluster disruption theories.

Findings

Cluster metallicities range from -0.02 to -0.19 dex.

Elemental abundances match those of thin disk giants within errors.

Results support the idea that field stars originate from disrupted open clusters.

Abstract

We have analyzed high-dispersion echelle spectra ($R \ga 50,000$) of red giant members for four open clusters to derive abundances for many elements. The spread in temperatures and gravities being very small among the red giants nearly the same stellar lines were employed thereby reducing the random errors. The errors of average abundance for the cluster were generally in 0.02 to 0.07 dex range. Our present sample covers galactocentric distances of 8.3 to 10.5 kpc. The [Fe/H] values are $-0.02\pm$0.05 for NGC 752, $-0.07\pm$0.06 for NGC 2360, $-0.11\pm$0.05 for NGC 1817 and $-0.19\pm$0.06 for NGC 2506. Abundances relative to Fe for elements from Na to Eu are equal within measurement uncertainties to published abundances for thin disk giants in the field. This supports the view that field stars come from disrupted open clusters.