Astron. Astrophys. 335, 1070-1076 (1998)
5. Conclusions
We have searched for several lines of the water dimer,
(H2O)2, toward Galactic hot cores and for one
line toward one Galactic dark cloud and toward comet Hale-Bopp. Our
main conclusions are:
-
No emission of water dimer lines was detected. This leads to upper
limits of the (H2O)2/H2O abundance of
typically 10-4 and in the case of Orion of
. Together with the limits for the
CO-H2 given by Allen et al. (1997) these are the most
stringent limits given for van der Waals complexes in the ISM.
-
Our nondetection of the water dimer toward comet Hale-Bopp limits
the production rate to at perihelion, and the
(H2O)2/H2O abundance to
. We suggest to look for serendipitous
detections of (H2O)2 in archived observations of
Hale-Bopp.
© European Southern Observatory (ESO) 1998
Online publication: June 26, 1998
helpdesk.link@springer.de  |