The ATCA/VLA OH 1612 MHz survey. I. Observations of the galactic bulge Region

Abstract

We present observations of the region between and in the OH 1612.231 MHz line, taken in 1993 October and November with the Australia Telescope Compact Array. The region was systematically searched for OH/IR stars and was covered completely with 539 pointing centres separated by 30. The size of the dataset calls for a special reduction technique that is fast, reliable and minimizes the output (positions and velocities of possible stars only). Having developed such a reduction method we found 307 OH masing objects, 145 of which are new detections. Out of these, 245 have a standard double-peaked spectral profile, 58 a single-peaked profile and 4 have nonstandard or irregular profiles. In this article we analyse the data statistically and give classifications and identifications with known sources where possible. The astrophysical, kinematical, morphological and dynamical properties of subsets of the data will be addressed in future articles. These observations are part of a larger survey, covering and , with the Australia Telescope Compact Array and the Very Large Array.