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Earth, Moon, and Planets

, Volume 78, Issue 1–3, pp 13–20 | Cite as

New Molecular Species in Comet C/1995 O1 (Hale-Bopp) Observed with the Caltech Ssubmillimeter Observatory

  • D. C. Lis
  • D. M. Mehringer
  • D. Benford
  • M. Gardner
  • T. G. Phillips
  • D. Bockelée-Morvan
  • N. Biver
  • P. Colom
  • J. Crovisier
  • D. Despois
  • H. Rauer
Article

Abstract

We present millimeter-wave observations of HNCO, HC3N, SO, NH2CHO, H13CN, and H3O+ in comet C/1995 O1 (Hale-Bopp)obtained in February–April, 1997 with the Caltech Submillimeter Observatory (CSO). HNCO, first detected at the CSO in comet C/1996B2 (Hyakutake), is securely confirmed in comet Hale-Bopp via observations of three rotational transitions. The derived abundance with respect to H2O is (4-13) × 10-4. HC3N, SO, and NH2CHO are detected for the first time in a comet. The fractional abundance of HC3N based on observations of three rotational lines is (1.9 ± 0.2) × 10-4. Four transitions of SO are detected and the derived fractional abundance, (2-8) ×10-3, is higher than the upper limits derived from UV observations of previous comets. Observations of NH2CHO imply a fractional abundance of (1-8) × 10-4. H3O is detected for the first time from the ground. The H13CN (3-2)transition is also detected and the derived HCN/H13CN abundance ratio is 90 ± 15, consistent with the terrestrial12C/13C ratio. In addition, a number of other molecular species are detected, including HNC, OCS, HCO+, CO+, and CN(the last two are first detections in a comet at radio wavelengths).

Comets composition radio observations spectroscopy 

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Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • D. C. Lis
    • 1
  • D. M. Mehringer
    • 1
  • D. Benford
    • 1
  • M. Gardner
    • 1
  • T. G. Phillips
    • 1
  • D. Bockelée-Morvan
    • 3
  • N. Biver
    • 3
  • P. Colom
    • 3
  • J. Crovisier
    • 2
  • D. Despois
    • 3
  • H. Rauer
    • 4
  1. 1.Downs Laboratory of PhysicsCalifornia Institute of TechnologyPasadenaUSA
  2. 2.Observatoire de ParisMeudon Principal CedexFrance
  3. 3.Observatoire de BordeauxFloiracFrance
  4. 4.DLR, Institut füur PlanetenerkundungBerlinGermany

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