A&A Supplement Ser., Vol. 124, July 1997, 85-108
Received August 26; accepted October 29, 1996
V.I. Slysh 
-
A.M. Dzura 
-
I.E. Val'tts 
-
E. Gerard 
Send offprint request: E. Gerard
Astro Space Center of Lebedev Physical Institute, Profsoyuznaya
84/32, 117810 Moscow, Russia
Departement de Radioastronomie, Observatoire de Paris, Section de
Meudon, F-91195 Meudon Principal Cedex, France
Results of a continued search for OH main line emission from IRAS sources are
reported. Towards a sample of 182 sources which consists of IRAS sources
selected by the colour criterion for ultracompact HII region, and several IRAS
cores, 
masers and bipolar outflows, we detected 19 new OH masers of
Class I and 5 OH/IR candidates. The correlation between IR and OH maser flux is
confirmed. Also 51 thermal and 4 absorption sources were detected. The low
radial velocities and derived OH column densities suggest that the thermal OH
emission comes from nearby dark clouds. There is evidence that IRAS sources
towards which thermal emission was detected are connected with these dark
clouds.
keywords: ISM: clouds -- ISM: molecules -- masers -- radio lines: ISM -- surveys