Weak ice absorption features at 7.24 and 7.41 mu m in the spectrum of the obscured young stellar object W 33A
| Autor: | Schutte, WA, Boogert, ACA, Tielens, AGGM, Whittet, DCB, Gerakines, PA, Chiar, JE, Ehrenfreund, P, Greenberg, JM, van Dishoeck, EF, de Graauw, T |
|---|---|
| Přispěvatelé: | Kapteyn Astronomical Institute |
| Jazyk: | angličtina |
| Rok vydání: | 1999 |
| Předmět: |
DENSE MOLECULAR CLOUDS
stars : individual : NGC 7538 : IRS 9 SWS OBSERVATIONS ISM : abundances MICRON ABSORPTION INFRARED-SPECTROSCOPY IR-SPECTRA ISM : molecules infrared : ISM : lines and bands INTERSTELLAR ICES SOLID-PHASE LABORATORY SIMULATIONS stars : individual : W 33A TIME-DEPENDENT CHEMISTRY GRAIN SURFACE-REACTIONS methods : laboratory |
| Zdroj: | Astronomy & astrophysics, 343(3), 966-976. EDP Sciences |
| ISSN: | 0004-6361 |
| Popis: | ISO-SWS observations of the highly obscured young stellar object W 33A reveal two broad absorption features centered at 7.24 and 7.41 mu m. Comparison to interstellar ice analogs shows that the 7.24 mu m band can be well matched by the CH deformation mode of formic acid(HCOOH), while the 7.41 mu m band can be fitted both by the formate ion (HCOO-) and acetaldehyde (CH3HCO) The laboratory spectra reveal additional strong features of these molecules which should make a more definite identification straightforward. While an assignment of the 7.24 mu m band to the -CH3 deformation mode of aliphatic species maybe considered, the absence of a corresponding strong CH stretching mode argues against this possibility;These results and the earlier tentative detection of HCOOH towards NGC7538:IRS9 suggest that formic acid is a general component of the ices in the vicinity of embedded high-mass young stellar objects. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|