LIGHT-ELEMENT ABUNDANCES OF GIANT STARS IN THE GLOBULAR CLUSTER M71 (NGC 6838)

Journal Article · Tue Feb 10 04:00:00 EST 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/800/1/3· OSTI ID:22364280

Cordero, M. J. ^[1]; Pilachowski, C. A.; Vesperini, E. ^[2]

---

1. Zentrum für Astronomie der Universität Heidelberg, Landessternwarte, Königstuhl 12, Heidelberg (Germany)
2. Astronomy Department, Indiana University Bloomington, Swain West 319, 727 East 3rd Street, Bloomington, IN 47405-7105 (United States)

Aluminum is the heaviest light element displaying large star-to-star variations in Galactic globular clusters (GCs). This element may provide additional insight into the origin of the multiple populations, now known to be common place in GCs, and also the nature of the first-generation stars responsible for a cluster's chemical inhomogeneities. In a previous analysis, we found that unlike more metal-poor GCs, 47 Tuc did not exhibit a strong Na-Al correlation, which motivates a careful study of the similar metallicity but less massive GC M71. We present chemical abundances of O, Na, Al, and Fe for 33 giants in M71 using spectra obtained with the WIYN-Hydra spectrograph. Our spectroscopic analysis finds that similar to 47 Tuc and in contrast with more metal-poor GCs, M71 stars do not exhibit a strong Na-Al correlation and span a relatively narrow range in [Al/Fe], which are characteristics that GC formation models must reproduce.

• OSTI ID: 22364280
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 800; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ALUMINIUM
CORRELATIONS
ELEMENT ABUNDANCE
GIANT STARS
IRON
METALLICITY
MILKY WAY
ORIGIN
SODIUM
STAR CLUSTERS
STAR EVOLUTION
STAR MODELS
VARIATIONS
VISIBLE RADIATION