The first 8 – 13 μ m spectra of globular cluster red giants : circumstellar silicate dust grains in 47 Tucanae ( NGC 104 )
نویسندگان
چکیده
We present 8–13 μm spectra of eight red giants in the globular cluster 47Tucanae (NGC104), 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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