Please use this identifier to cite or link to this item:
http://hdl.handle.net/20.500.12386/23522
Title: | Exploring Anticorrelations and Light Element Variations in Northern Globular Clusters Observed by the APOGEE Survey | Authors: | Mészáros, Szabolcs Martell, Sarah L. Shetrone, Matthew LUCATELLO, Sara Troup, Nicholas W. Bovy, Jo Cunha, Katia García-Hernández, Domingo A. Overbeek, Jamie C. Allende Prieto, Carlos Beers, Timothy C. Frinchaboy, Peter M. García Pérez, Ana E. Hearty, Fred R. Holtzman, Jon Majewski, Steven R. Nidever, David L. Schiavon, Ricardo P. Schneider, Donald P. Sobeck, Jennifer S. Smith, Verne V. Zamora, Olga Zasowski, Gail |
Issue Date: | 2015 | Journal: | THE ASTRONOMICAL JOURNAL | Number: | 149 | Issue: | 5 | First Page: | 153 | Abstract: | We investigate the light-element behavior of red giant stars in northern globular clusters (GCs) observed by the SDSS-III Apache Point Observatory Galactic Evolution Experiment. We derive abundances of 9 elements (Fe, C, N, O, Mg, Al, Si, Ca, and Ti) for 428 red giant stars in 10 GCs. The intrinsic abundance range relative to measurement errors is examined, and the well-known C-N and Mg-Al anticorrelations are explored using an extreme-deconvolution code for the first time in a consistent way. We find that Mg and Al drive the population membership in most clusters, except in M107 and M71, the two most metal-rich clusters in our study, where the grouping is most sensitive to N. We also find a diversity in the abundance distributions, with some clusters exhibiting clear abundance bimodalities (for example M3 and M53) while others show extended distributions. The spread of Al abundances increases significantly as cluster average metallicity decreases as previously found by other works, which we take as evidence that low metallicity, intermediate mass AGB polluters were more common in the more metal-poor clusters. The statistically significant correlation of [Al/Fe] with [Si/Fe] in M15 suggests that <SUP>28</SUP>Si leakage has occurred in this cluster. We also present C, N, and O abundances for stars cooler than 4500 K and examine the behavior of A(C+N+O) in each cluster as a function of temperature and [Al/Fe]. The scatter of A(C+N+O) is close to its estimated uncertainty in all clusters and independent of stellar temperature. A(C+N+O) exhibits small correlations and anticorrelations with [Al/Fe] in M3 and M13, but we cannot be certain about these relations given the size of our abundance uncertainties. Star-to-star variations of α-element (Si, Ca, Ti) abundances are comparable to our estimated errors in all clusters. | Acknowledgments: | Szabolcs Mészáros is especially grateful for the technical expertise and assistance provided by the Department of Astronomy at Indiana University. We thank Eileen D. Friel, Catherine A. Pilachowski, and Enrico Vesperini for their detailed comments during the development of autosynth. Sarah Martell acknowledges the support of the Australian Research Council through DECRA Fellowship DE140100598. Sara Lucatello acknowledges partial support from grant PRIN MIUR 2010-2011 “Chemical and dynamical evolution of the Milky Way and Local Group Galaxies.” Jo Bovy was supported by NASA through Hubble Fellowship grant HST -HF-51285.01 from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Timothy C. Beers acknowledges partial support for this work from grants PHY 08-22648; Physics Frontier Center/Joint Institute or Nuclear Astrophysics (JINA), and PHY 14-30152; Physics Frontier Center/JINA Center for the Evolution of the Elements (JINA-CEE), awarded by the US National Science Foundation. Katia Cunha acknowledges support for this research from the National Science Foundation (AST-0907873). Verne V. Smith acknowledges partial support for this research from the National Science Foundation (AST-1109888). D. A. García-Hernández and Olga Zamora acknowledge support provided by the Spanish Ministry of Economy and Competitiveness under grant AYA-2011-27754. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. The SDSS-III website is http://sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, University of Cambridge, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University. | URI: | http://hdl.handle.net/20.500.12386/23522 | URL: | https://iopscience.iop.org/article/10.1088/0004-6256/149/5/153 | ISSN: | 0004-6256 | DOI: | 10.1088/0004-6256/149/5/153 | Bibcode ADS: | 2015AJ....149..153M | Fulltext: | open |
Appears in Collections: | 1.01 Articoli in rivista |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
Mészáros_2015_AJ_149_153.pdf | 1.78 MB | Adobe PDF | View/Open |
Page view(s)
59
checked on Sep 19, 2024
Download(s)
18
checked on Sep 19, 2024
Google ScholarTM
Check
Altmetric
Altmetric
Items in DSpace are published in Open Access, unless otherwise indicated.