Accurate OH maser positions from the SPLASH pilot region
  We report on high spatial resolution observations, using the Australia
Telescope Compact Array (ATCA), of ground-state OH masers. These observations
were carried out toward 196 pointing centres previously identified in the
Southern Parkes Large-Area Survey in Hydroxyl (SPLASH) pilot region, between
Galactic longitudes of $334^{\circ}$ and $344^{\circ}$ and Galactic latitudes
of $-2^{\circ}$ and $+2^{\circ}$. Supplementing our data with data from the
MAGMO (Mapping the Galactic Magnetic field through OH masers) survey, we find
maser emission towards 175 of the 196 target fields. We conclude that about
half of the 21 non-detections were due to intrinsic variability. Due to the
superior sensitivity of the follow-up ATCA observations, and the ability to
resolve nearby sources into separate sites, we have identified 215 OH maser
sites towards the 175 fields with detections. Among these 215 OH maser sites,
111 are new detections. After comparing the positions of these 215 maser sites
to the literature, we identify 122 (57 per cent) sites associated with evolved
stars (one of which is a planetary nebula), 64 (30 per cent) with star
formation, two sites with supernova remnants and 27 (13 per cent) of unknown
origin. The infrared colors of evolved star sites with symmetric maser profiles
tend to be redder than those of evolved star sites with asymmetric maser
profiles, which may indicate that symmetric sources are generally at an earlier
evolutionary stage.
