Data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The observatory was made possible for studies by the generous support of the W. M. Keck Foundation.
High-resolution near-infrared spectra of NGC 6624 and 6569★
Article first published online: 15 APR 2011
© 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS
Monthly Notices of the Royal Astronomical Society
Volume 414, Issue 3, pages 2690–2695, July 2011
How to Cite
Valenti, E., Origlia, L. and Rich, R. M. (2011), High-resolution near-infrared spectra of NGC 6624 and 6569. Monthly Notices of the Royal Astronomical Society, 414: 2690–2695. doi: 10.1111/j.1365-2966.2011.18580.x
- Issue published online: 21 JUN 2011
- Article first published online: 15 APR 2011
- Accepted 2011 February 22. Received 2011 February 21; in original form 2010 November 17
- techniques: spectroscopic;
- stars: abundances;
- stars: late-type;
- Galaxy: bulge;
- globular clusters: individual: NGC 6569;
- globular clusters: individual: NGC 6624
We present the first abundance analysis based on high-resolution infrared (IR) echelle spectra of NGC 6569 and 6624, two moderately reddened globular clusters located in the outer bulge of the Galaxy.
We find [Fe/H]=−0.79 ± 0.02 and −0.69 ± 0.02 dex for NGC 6569 and 6624, respectively, and an average α-element enhancement of ≈+0.43 ± 0.02 and +0.39 ± 0.02 dex, consistent with previous measurements on other metal-rich bulge clusters. We measure accurate radial velocities of 〈vr〉=−47 ± 4 and +51 ± 3 km s−1 and velocity dispersions of ≈8 and 6 km s−1 for NGC 6569 and 6624, respectively.
Finally, we find very low 12C/13C isotopic ratio (≤7 in NGC 6624 and ≈5 in NGC 6569), confirming the presence of extramixing mechanisms during the red giant branch evolution phase.