Stellar abundances and ages for metal-rich Milky Way globular clusters - Stellar parameters and elemental abundances for 9 HB stars in NGC6352

TL;DR

This study provides detailed elemental abundances and stellar parameters for nine HB stars in the metal-rich globular cluster NGC6352, enhancing understanding of Galactic formation and calibration of extragalactic stellar populations.

Contribution

First high-resolution spectroscopic analysis of nine HB stars in NGC6352, offering new metallicity and elemental abundance data for a metal-rich globular cluster.

Findings

NGC6352 has [Fe/H] = -0.55 and alpha-element enhancement of +0.2 dex.

Solar values for iron-peak elements in NGC6352.

Refined reddening and distance modulus estimates for NGC6352.

Abstract

[ABRIDGED] Metal-rich globular clusters provide important tracers of the formation of our Galaxy. Moreover, and not less important, they are very important calibrators for the derivation of properties of extra-galactic metal-rich stellar populations. Nonetheless, only a few of the metal-rich globular clusters in the Milky Way have been studied using high-resolution stellar spectra to derive elemental abundances. In this paper we present elemental abundances for nine HB stars in the metal-rich globular cluster NGC6352. The elemental abundances are based on high-resolution, high signal-to-noise spectra obtained with VLT/UVES. The elemental abundances have been derived using standard LTE calculations. We find that NGC6352 has [Fe/H]= -0.55, is enhanced in the alpha-elements to about +0.2 dex for Ca, Si, and Ti relative to Fe. For the iron-peak elements we find solar values. Based on the spectroscopically derived stellar parameters we find that an E(B-V)=0.24 and (m-M) roughly equal to 14.05 better fits the data than the nominal values. An investigation of log(gf)-values for suitable FeI lines lead us to the conclusion that the commonly used correction to the May et al.(1974) data should not be employed. Note: only the postscript reproduces the finding chart correctly.