Chemical abundances in the metal-intermediate GC NGC 6723
Abstract
We have performed a detailed spectral analysis of the inner halo Galactic globular cluster (GC) NGC 6723 using high-resolution (R 22000-48000) spectra for for 11 red giant branch stars collected with MIKE (Magellan) and FEROS (MPG/ESO). This globular is located at the minimum of the bimodal metallicity distribution of GCs, which suggests that it might be an excellent transitional system between metal-intermediate and metal-rich GCs. In spite of its metal-intermediate status, it is characterized by an extended horizontal branch and by a large number of RR Lyrae stars. We investigated abundances of a variety of species, including light, -, Fe-peak, and neutron-capture elements. We found a mean metallicity dex and typical -enrichment () that follows the trend of metal-poor and metal-intermediate GCs. The same outcome applies for light metals (Na, Al), Fe-peak (V, Cr, Mn, Fe, Co, Ni, Cu) and s/r-process elements (Ba, Eu), and for the classical anticorrelation: Na-O and Mg-Al. The current findings further support the evidence that the chemical enrichment of NGC 6723 is more in line with metal-intermediate GCs and their lower metallicity counterparts, and it does not bring forward the prodrome of the metal-rich regime.
Más información
Título según WOS: | Chemical abundances in the metal-intermediate GC NGC 6723 |
Título según SCOPUS: | Chemical abundances in the metal-intermediate GC NGC 6723 |
Título de la Revista: | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY |
Volumen: | 487 |
Número: | 4 |
Editorial: | OXFORD UNIV PRESS |
Fecha de publicación: | 2019 |
Página de inicio: | 5463 |
Página final: | 5474 |
Idioma: | English |
DOI: |
10.1093/mnras/stz1674 |
Notas: | ISI, SCOPUS |