LABORATORY CHARACTERIZATION AND ASTROPHYSICAL DETECTION OF VIBRATIONALLY EXCITED STATES OF ETHYL CYANIDE

Journal Article · Wed May 01 00:00:00 EDT 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/768/1/81· OSTI ID:22126780

Daly, A. M.; Bermudez, C.; Alonso, J. L. ^[1]; Lopez, A.; Tercero, B.; Cernicharo, J. ^[2]; Pearson, J. C. ^[3]

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1. Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Area de Quimica-Fisica, Laboratorios de Espectroscopia y Bioespectroscopia, Unidad Asociada del CSIC, Universidad de Valladolid, E-47005 Valladolid (Spain)
2. Department of Astrophysics, CAB, INTA-CSIC, Crta Torrejon, E-28850 Torrejon de Ardoz, Madrid (Spain)
3. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Padadena, CA 91109 (United States)

Ethyl cyanide, CH{sub 3}CH{sub 2}CN, is an important interstellar molecule with a very dense rotational-vibrational spectrum. On the basis of new laboratory data in the range of 17-605 GHz and ab initio calculations, two new vibrational states, {nu}{sub 12} and {nu}{sub 20}, have been detected in molecular clouds of Orion. Laboratory data consist of Stark spectroscopy (17-110 GHz) and frequency-modulated spectrometers (GEM laboratory in Valladolid: 17-170, 270-360 GHz; Toyama: 26-200 GHz; Emory: 200-240 GHz; Ohio State: 258-368 GHz; and JPL: 270-318, 395-605 GHz). More than 700 distinct lines of each species were measured in J up to 71 and in K{sub a} up to 25. The states were fitted with Watson's S-reduction Hamiltonian. The two new states have been identified in the interstellar medium toward the Orion Nebula (Orion KL). The ground state, the isotopologues of CH{sub 3}CH{sub 2}CN, and the vibrationally excited states have been fitted to obtain column densities and to derive vibrational temperatures. All together, ethyl cyanide is responsible for more than 2000 lines in the observed frequency range of 80-280 GHz.

• OSTI ID: 22126780
• Journal Information: Astrophysical Journal, Vol. 768, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ASTROPHYSICS
CLOUDS
CYANIDES
DENSITY
DETECTION
GHZ RANGE
GROUND STATES
HAMILTONIANS
NEBULAE
SPECTRA
SPECTROMETERS
SPECTROSCOPY
VIBRATIONAL STATES