Work

Metal Abundances in Extremely Distant Galactic Old Open Clusters. I. Berkeley 29 and Saurer 1

Year: 2004

Type: article

Abstract: We report on high-resolution spectroscopy of four giant stars in the Galactic old open clusters Berkeley 29 and Saurer 1 obtained with HIRES at the Keck Telescope. These two clusters possess the largest Galactocentric distances yet known for open star clusters and therefore are crucial objects to probe the chemical pattern and evolution of the outskirts of the Galactic disk. We find that [Fe/H] = -0.38 ± 0.14 and -0.44 ± 0.18 for Saurer 1 and Berkeley 29, respectively. On the basis of these data, we first revise the fundamental parameters of the clusters and then discuss them in the context of the Galactic disk radial abundance gradients. Both clusters seem to significantly deviate from the general trend, suggesting that the outer part of the Galactic disk underwent a completely different evolution compared with the inner disk. In particular, Berkeley 29 is clearly associated with the Monoceros stream, whereas Saurer 1 exhibits very different properties. The abundance ratios suggest that the chemical evolution of the outer disk was dominated by the Galactic halo.

Source: The Astronomical Journal

DOI: 10.1086/423912

Authors: Giovanni Carraro, Fabio Bresolin, Sandro Villanova, Francesca Matteucci, Ferdinando Patat, Martino Romaniello

Institutions: University of Padua, Yale University, University of Chile, Osservatorio Astronomico di Padova, University of Trieste, European Southern Observatory

Language: English

Topic: Stellar, planetary, and galactic studies

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: bronze

Funders: National Aeronautics and Space Administration, W. M. Keck Foundation, California Institute of Technology

OpenAlex ID: W2014537323

FWCI: 4.501

Cites: 25

Cited by: 85

Related to: 10