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The first 8-13 micron spectra of globular cluster red giants: circumstellar silicate dust grains in 47 Tucanae (NGC 104)

Jacco Th. van Loon·Iain McDonald·Joana M. Oliveira·A. Evans·Martha L. Boyer·Robert D. Gehrz·Elisha Polomski·Charles E. Woodward
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Abstract

We present 8-13 micron spectra of eight red giants in the globular cluster 47 Tucanae (NGC 104), obtained at the European Southern Observatory 3.6m telescope. These are the first mid-infrared spectra of metal-poor, low-mass stars. The spectrum of at least one of these, namely the extremely red, large-amplitude variable V1, shows direct evidence of circumstellar grains made of amorphous silicate.

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Jacco Th. van Loon, Iain McDonald, Joana M. Oliveira, A. Evans, Martha L. Boyer, Robert D. Gehrz, Elisha Polomski, Charles E. Woodward. 2006-01-04. The first 8-13 micron spectra of globular cluster red giants: circumstellar silicate dust grains in 47 Tucanae (NGC 104). https://doi.org/10.1051/0004-6361%3A20054702

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