CO Observations of the -Orionis Ring

Observations

Using the 1.2m radiotelescope at the Harvard-Smithsonian Center for Astrophysics, we have surveyed a 1011 area covering the -Orionis OB-association (Murdin & Penston, 1977), the HII region S264 (eg. Reich 1978) and the prominent surrounding ring of dust (Zhang et al. 1989) and gas (Wade 1957, Maddalena & Morris 1987 - henceforth `MM'). The data were taken on a uniform grid in Galactic Coordinates with half-beamwidth sampling. The telescope HPBW is 8.4' at 115 GHz, corresponding to 1.16 pc at 400 pc, the estimated distance to the -Ori association. The 28,855 spectra each have a sensitivity per channel of 0.25K (T), and velocity resolution is 0.65 km s. The resulting datacube (v,l,b) is smoothed to 10' resolution at 0.12K sensitivity, covering the velocity range [-10,+20] km s with respect to the LSR.

© Copyright Astronomical Society of Australia 1997