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arXiv · 0809.4300

The 16OH/18OH and OD/OH isotope ratios in comet C/2002 T7 (LINEAR)

D. Hutsemekers·J. Manfroid·E. Jehin·J. -M. Zucconi·C. Arpigny
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Abstract

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 A (0,0) and 3121 A (1,1) secured with the Very Large Telescope (VLT) feeding the Ultraviolet-Visual Echelle Spectrograph (UVES). From the 16OH/18OH ratio, we find 16O/18O = 425 +/- 55, 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 D/H = 2.5 +/- 0.7 10-4 in water. This value is compatible with the water D/H ratios evaluated in other comets and marginally higher than the terrestrial value.

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D. Hutsemekers, J. Manfroid, E. Jehin, J. -M. Zucconi, C. Arpigny. 2008-09-25. The 16OH/18OH and OD/OH isotope ratios in comet C/2002 T7 (LINEAR). https://doi.org/10.1051/0004-6361%3A200810833

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