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The rotational emission-line spectrum of Orion A between 247 and 263 GHz

Blake, Geoffrey A. and Sutton, E. C. and Masson, C. R. and Phillips, T. G. (1986) The rotational emission-line spectrum of Orion A between 247 and 263 GHz. Astrophysical Journal Supplement Series, 60 (1). pp. 357-374. ISSN 0067-0049.

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Results are presented from a molecular line survey of the core of the Orion molecular cloud between 247 and 263 GHz. The spectrum contains a total of 243 resolvable lines from 23 different chemical species. When combined with the earlier survey of Orion from 215 to 247 GHz by Sutton et al. (1985), the complete data set includes over 780 emission features from 29 distinct molecules. Of the 23 molecules detected in this survey, only NO, CCH, and HCO^+ were not identified in the lower frequency data. As a result of the supporting laboratory spectroscopy performed to supplement existing millimeter-wave spectral line catalogs, only 33 of the more than 780 lines remain unidentified, of which 16 occur in the upper frequency band. A significant chance remains that a number of these unidentified lines are due to transitions between states of either isotopically substituted or highly excited abundant and complex molecules such as CH_3OH, CH_3OCH_3, and HCOOCH_3, whose rotational spectra are poorly known at present. The very small percentage and weak strength of the unidentified lines implies that the dominant chemical constituents visible at millimeter wavelengths have been identified in the Orion molecular cloud.

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Blake, Geoffrey A.0000-0003-0787-1610
Additional Information:© 1986 American Astronomical Society. Provided by the NASA Astrophysics Data System. Received 1985 May 23; accepted 1985 July 15. The authors are especially grateful to F. C. De Lucia, E. Herbst, G. M. Plummer, F. J. Lovas, and H. M. Pickett for undertaking the large body of supporting laboratory work necessary for the successful completion of the Orion surveys, and for allowing us to use their spectra line catalogs. We would also like to thank D.P. Woody and S. L. Scott for their efforts in ensuring successful observations, and R. E. Miller of AT&T Bell Laboratories, Murray Hill, for supplying the junctions used in this work. Single-dish millimeter-wave astronomy at the Owens Valley Radio Observatory is supported by NSF grants AST-8214693 and 8311849.
Group:UNSPECIFIED, Division of Geological and Planetary Sciences
Funding AgencyGrant Number
Subject Keywords:interstellar: molecules; line identifications; nebulae: Orion Nebula
Issue or Number:1
Record Number:CaltechAUTHORS:20120912-073534077
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Official Citation:The rotational emission-line spectrum of Orion A between 247 and 263 GHz Blake, G. A.; Masson, C. R.; Phillips, T. G.; Sutton, E. C.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:34012
Deposited By: Ruth Sustaita
Deposited On:12 Sep 2012 15:05
Last Modified:03 Oct 2019 04:15

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