RADIO OBSERVATIONS OF H II REGIONS WITH NARROW RADIO RECOMBINATION LINES

We report observations of the H110-alpha and H138-beta recombination lines and of the J = 1 - 0 rotational transition of CO toward H II regions suspected of having narrow radio recombination lines from the results of surveys with modest signal-to-noise ratio. Only one of the sources studied, G0.6-0.6, was found to have anomalously narrow recombination line emission, DELTA-upsilon (H110-alpha) congruent-to 14.4 +/- 0.4 km s-1. However, as a group, the sources studied by us have lines that are systematically narrower than "typical" H II regions. G0.6-0.6 and G19.5 + 0.1 are also unsual in having very little "turbulent" broadening in their recombination line emission. Another H II region in our sample, G19.6-0.1, seems to have created a blister-like cavity in its associated molecular cloud. There is no obvious difference between our selected sample of H II region-molecular cloud associations and the larger samples studied by others.