Further studies of vibrationally excited cyanoacetylene near Orion IRc2 and other sources

Abstract

view Abstract Citations (24) References (41) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Further studies of vibrationally excited cyanoacetylene near Orion IRc2 and other sources. Goldsmith, P. F. ; Krotkov, R. ; Snell, R. L. Abstract The J = 12 to 11 transition of the v6 = 1 vibrationally excited state of HC3N has been detected in emission from the Orion molecular cloud. The upper level lies 750 K above the molecular ground state, and the emission can be produced only in regions of strong excitation such as the hot core; this identification is consistent with the line velocity and width. The vibrational excitation temperature of v6 = 1 is 150 K, essentially the same as that of the v7 = 1 and v7 = 2 states reported previously. The extremely rapid spontaneous emission rate, 0.12/s, demands unreasonably high particle densities for collisions to produce the observed excitation, but is in general agreement with excitation by absorption of infrared radiation at the 20 micron wavelength of the vibrational transition. A model of the infrared excitation in the shell outside of a cavity immediately surrounding IRc2 gives satisfactory agreement with the observed intensities for reasonable choices for parameters of the exciting source and the surrounding cloud. Publication: The Astrophysical Journal Pub Date: December 1985 DOI: 10.1086/163709 Bibcode: 1985ApJ...299..405G Keywords: Acetylene; Cyano Compounds; Interstellar Matter; Molecular Clouds; Orion Nebula; Cyanoacetylene; Infrared Spectra; Line Spectra; Molecular Collisions; Molecular Excitation; Vibrational Spectra; Astrophysics full text sources ADS | data products SIMBAD (16)