Vibrationally excited CH/sub 3/CN and HC/sub 3/N in orion

Journal Article · Tue Nov 01 04:00:00 EST 1983 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/161436· OSTI ID:6860906

Goldsmith, P F; Krotkov, R; Snell, R L; Brown, R D; Godfrey, P

We report the detection of vibrationally excited CH/sub 3/CN (methyl cyanide) in the ..nu../sub 8/ vibrational state, which lies approximately 520 K above the ground state. The line velocities (approx.6 km s/sup -1/) and widths (approx.10 km s/sup -/)/sup / indicate that this emission is being produced in the hot core region located in the central portion of the Orion molecular cloud. The vibrational excitation temperature is estimated to be between 200 and 350 K, which could be produced by infrared radiation within a region approx.3'' (2 x 10/sup 16/ cm) of an L = 10/sup 5/ L. IR source. The density required for collisional excitation, 10/sup 10/-10/sup 11/ cm/sup -3/, seems excessive for the minimum source size which is also approximately 3''. Detection of the J = 12..-->..11 rotational transition of HC/sub 3/N (cyanoacetylene) in the 2..nu../sub 7/ state confirms the degree of vibrational excitation determined previously (Goldsmith et al.); the HC/sub 3/N excitation (T/sub EX/approx.150 K) is somewhat less than that of CH/sub 3/CN and the source size is approx.6'' in diameter. SO/sub 2/ emission in the ..nu../sub 2/ vibrationally excited state was searched for, but not detected.

• Research Organization: Five Collect Astronomy Observatory, University of Massachusetts, Amherst
• OSTI ID: 6860906
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 274:1; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CYANOGEN
EMISSION SPECTRA
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXCITED STATES
INTERSTELLAR GRAINS
NEBULAE
NITRILES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PARTICLES
PROPIOLONITRILE
ROTATIONAL STATES
SPECTRA
VIBRATIONAL STATES