Detection of Interstellar Vibrationally Excited HCN
Abstract
Vibrationally excited HCN has been observed for the first time in the interstellar medium. The J = 3-2 rotational transitions of the l-doubled (0,11d,1c,0) bending mode of HCN have been detected toward Orion-KL and IRC +10216. In Orion, the overall column density in the (0,1,0) mode, which exclusivley samples the "hot core", is 1.7×1016cm-2 and can be understood in terms of the "doughnut" model for Orion. Radiative excitation by 14 μm flux from IRc2 accounts for the (0,1,0) population, provided the hot core is ≡ 6 - 7×1016cm distant from IRc2. Toward IRC +10216 the authors have detected J = 3-2 transitions of both (0,11c,1d,0) and (0,20,0) excited states.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1986
- DOI:
- 10.1086/184595
- Bibcode:
- 1986ApJ...300L..19Z
- Keywords:
-
- Abundance;
- Hydrocyanic Acid;
- Interstellar Matter;
- Molecular Oscillations;
- Orion Nebula;
- Electron Transitions;
- Stellar Envelopes;
- Astrophysics;
- INTERSTELLAR: ABUNDANCES;
- INTERSTELLAR: MOLECULES;
- NEBULAE: ORION NEBULA;
- STARS: CIRCUMSTELLAR SHELLS