The circumstellar water fountains of IRAS 16342-3814: a very high velocity bipolar outflow

Maser emission from OH and H/sub 2/O is observed to be present over an exceptionally wide range of velocities in the cold, stellar infrared source IRAS 16342-3814. OH emission at 1612, 1665, and 1667 MHz spans 130 km/s, a range far larger than in any other known OH/IR star. The H/sub 2/O emission features appear as two widely separated doublets with a full velocity spread of 259 km/s. Several lines of evidence point to the conclusion that IRAS 16342-3814 is an evolved star with a bipolar outflow, related to objects such as OH 231.8 + 4.2 and M1 - 92. The H/sub 2/O masers are interpreted as streams or clumps of molecular gas forced out the polar axes by, or as part of, a wind from an accretion disk, while the OH masers appear to arise from lower velocity material at intermediate latitudes. 20 references.