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