Polycyclic Aromatic Hydrocarbons Orbiting Hd 233517, an Evolved Oxygen-rich Red Giant
نویسندگان
چکیده
We report spectra obtained with the Spitzer Space Telescope in the λ = 5 – 35 μm range of HD 233517, an evolved K2 III giant with circumstellar dust. For λ > 13 μm, the flux is a smooth continuum that varies approximately as ν. For λ < 13 μm, although the star is oxygen-rich, PAH features produced by carbon-rich species at 6.3 μm, 8.2 μm, 11.3 μm and 12.7 μm are detected along with likely broad silicate emission near 20 μm. These results can be explained if there is a passive, flared disk orbiting HD 233517. Our data support the hypothesis that organic molecules in orbiting disks may be synthesized in situ as well as being incorporated from the interstellar medium. Subject headings: circumstellar matter – stars, red giant
منابع مشابه
ar X iv : a st ro - p h / 05 12 37 1 v 1 1 4 D ec 2 00 5 POLYCYCLIC AROMATIC HYDROCARBONS ORBITING HD 233517 , AN EVOLVED OXYGEN - RICH RED GIANT
We report spectra obtained with the Spitzer Space Telescope in the λ = 5 – 35 μm range of HD 233517, an evolved K2 III giant with circumstellar dust. For λ > 13 μm, the flux is a smooth continuum that varies approximately as ν. For λ < 13 μm, although the star is oxygen-rich, PAH features produced by carbon-rich species at 6.3 μm, 8.2 μm, 11.3 μm and 12.7 μm are detected along with likely broad...
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