FUNDAMENTAL PARAMETERS, INTEGRATED RED GIANT BRANCH MASS LOSS, AND DUST PRODUCTION IN THE GALACTIC GLOBULAR CLUSTER 47 TUCANAE

Journal Article · Fri Apr 01 04:00:00 EDT 2011 · Astrophysical Journal, Supplement Series

DOI:https://doi.org/10.1088/0067-0049/193/2/23· OSTI ID:21560421

McDonald, I; Zijlstra, A A ^[1]; Boyer, M L; Gordon, K; Meixner, M; Sewilo, M; Shiao, B; Whitney, B ^[2]; Van Loon, J Th ^[3]; Hora, J L; Robitaille, T ^[4]; Babler, B; Meade, M ^[5]; Block, M; Misselt, K ^[6]

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1. Jodrell Bank Centre for Astrophysics, Alan Turing Building, Manchester, M13 9PL (United Kingdom)
2. STScI, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
3. Lennard-Jones Laboratories, Keele University, ST5 5BG (United Kingdom)
4. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 65, Cambridge, MA 02138-1516 (United States)
5. Department of Astronomy, University of Wisconsin, Madison, 475 North Charter Street, Madison, WI 53706-1582 (United States)
6. Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tuscon, AZ 85721 (United States)

Fundamental parameters and time evolution of mass loss are investigated for post-main-sequence stars in the Galactic globular cluster 47 Tucanae (NGC 104). This is accomplished by fitting spectral energy distributions (SEDs) to existing optical and infrared photometry and spectroscopy, to produce a true Hertzsprung-Russell diagram. We confirm the cluster's distance as d = 4611{sup +213}{sub -200} pc and age as 12 {+-} 1 Gyr. Horizontal branch models appear to confirm that no more red giant branch mass loss occurs in 47 Tuc than in the more metal-poor {omega} Centauri, though difficulties arise due to inconsistencies between the models. Using our SEDs, we identify those stars that exhibit infrared excess, finding excess only among the brightest giants: dusty mass loss begins at a luminosity of {approx}1000 L{sub sun}, becoming ubiquitous above L = 2000 L{sub sun}. Recent claims of dust production around lower-luminosity giants cannot be reproduced, despite using the same archival Spitzer imagery.

• OSTI ID: 21560421
• Journal Information: Astrophysical Journal, Supplement Series, Journal Name: Astrophysical Journal, Supplement Series Journal Issue: 2 Vol. 193; ISSN 0067-0049; ISSN APJSA2
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
DIAGRAMS
DUSTS
ENERGY SPECTRA
HERTZSPRUNG-RUSSELL DIAGRAM
INFORMATION
LUMINOSITY
MAIN SEQUENCE STARS
MASS TRANSFER
OPTICAL PROPERTIES
PHOTOMETRY
PHYSICAL PROPERTIES
SPECTRA
SPECTROSCOPY
STARS