| Issue |
Astron. Astrophys. Suppl. Ser.
Volume 139, Number 3, November I 1999
|
|
|---|---|---|
| Page(s) | 625 - 628 | |
| DOI | https://doi.org/10.1051/aas:1999410 | |
| Published online | 15 November 1999 | |
Hyperfine population measurement of excited
OH from 
photodissociation by microwave stimulation – first results
1
Angewandte Laserphysik, University of Bielefeld, Universitaetsstr. 25, D-33615 Bielefeld, Germany
2
Department of Molecular and Laser Physics, University Nijmegen, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands
Corresponding author: Send offprint request to: T. ThissenAngewandte Laserphysik, University of Bielefeld, Universitaetsstr. 25, 33615 Bielefeld, Germany.
Received:
17
February
1999
Accepted:
22
July
1999
In this paper the first measurement of the hyperfine population of a photofragment is presented.
The population of the hyperfine levels of the 
state of OH out of
photodissociation of cold turns out to be statistical.
After photodissociation of water at 157 nm within a Fabry-Perot microwave cavity the nascent OH
formed in the 
, 
state (probed by LIF) is stimulated by microwave radiation. From saturation data
the population in each hyperfine level in both Λ-doublets is determined.
Key words: masers / molecular data / ISM: molecules / radio lines: ISM
© European Southern Observatory (ESO), 1999