DUST PRODUCTION AND MASS LOSS IN THE GALACTIC GLOBULAR CLUSTER 47 TUCANAE

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

DOI:https://doi.org/10.1088/0004-637X/730/2/71· OSTI ID:21574864

McDonald, I; Zijlstra, A A ^[1]; Boyer, M L ^[2]

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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)

Dust production among post-main-sequence stars is investigated in the Galactic globular cluster 47 Tucanae (NGC 104) based on infrared photometry and spectroscopy. We identify metallic iron grains as the probable dominant opacity source in these winds. Typical evolutionary timescales of asymptotic giant branch stars suggest the mass-loss rates we report are too high. We suggest that this is because the iron grains are small or elongated and/or that iron condenses more efficiently than at solar metallicity. Comparison to other works suggests metallic iron is observed to be more prevalent toward lower metallicities. The reasons for this are explored, but remain unclear. Meanwhile, the luminosity at which dusty mass loss begins is largely invariant with metallicity, but its presence correlates strongly with long-period variability. This suggests that the winds of low-mass stars have a significant driver that is not radiation pressure, but may be acoustic driving by pulsations.

• OSTI ID: 21574864
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 730; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
DUSTS
ELECTROMAGNETIC RADIATION
INFRARED RADIATION
LOSSES
MASS
PHOTOMETRY
RADIATIONS
STAR CLUSTERS
STARS
WIND