Volume 440, Number 2, September III 2005
|Page(s)||L21 - L24|
|Published online||01 September 2005|
Letter to the Editor
Isotopic abundances of carbon and nitrogen in Jupiter-family and Oort Cloud comets
Institut d'Astrophysique et de Géophysique, Université de Liège, Allée du 6 août 17, 4000 Liège, Belgium e-mail: email@example.com
2 European Southern Observatory, Casilla 19001, Santiago, Chile
3 Department of Astronomy and McDonald Observatory, University of Texas at Austin, C-1400, Austin, USA
4 ESA/RSSD, ESTEC, PO Box 299, 2200 AG Noordwijk, The Netherlands
5 Leiden Observatory, 2300 RA Leiden, The Netherlands
6 Observatoire de Besançon, 25010 Besançon Cedex, France
Accepted: 21 July 2005
The 12C14N/12C15N and 12C14N/13C14N isotopic ratios are determined for the first time in a Jupiter-family comet, 88P/1981 Q1 Howell, and in the chemically peculiar Oort Cloud comet C/1999 S4 (LINEAR). By comparing these measurements to previous ones derived for six other Oort Cloud comets (including one of Halley-type), we find that both the carbon and nitrogen isotopic ratios are constant within the uncertainties. The mean values are 12C/13C 90 and 14N/15N for the eight comets. These results strengthen the view that CN radicals originate from refractory organics formed in the protosolar molecular cloud and subsequently incorporated in comets.
Key words: comets: abundances / comets: individual: 88P/Howell / comets: individual: C/1999 S4 (LINEAR)
© ESO, 2005
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.