Letter to the Editor
The OH/OH and OD/OH isotope ratios in comet C/2002 T7 (LINEAR)*
Institut d'Astrophysique et de Géophysique, Université de Liège, Allée du 6 août 17, 4000 Liège, Belgique e-mail: firstname.lastname@example.org
2 Observatoire de Besançon, 25010 Besançon Cedex, France
Accepted: 23 September 2008
The 16OH/18OH and OD/OH isotope ratios are measured in the Oort-Cloud comet C/2002 T7 (LINEAR) through ground-based observations of the OH ultraviolet bands at 3063 Å (0, 0) and 3121 Å (1, 1) obtained with the Very Large Telescope (VLT) feeding the Ultraviolet-Visual Echelle Spectrograph (UVES). From the 16OH/18OH ratio, we find 16O/18O = , equal within the uncertainties to the terrestrial value and to the ratio measured in other comets, although marginally smaller. We also estimate OD/OH from which we derive in water. This value is compatible with the water D/H ratios evaluated in other comets and is marginally higher than the terrestrial value.
Key words: comets: general / comets: individual: C/2002 T7 (LINEAR)
© ESO, 2008