Key points are not available for this paper at this time.
An extensive search for emission from the 8.7 GHz hyperfine line of 3He+ in 17 Galactic H II regions has yielded new detections in six regions and significant upper limits for the others. The authors derive the (3He/H) abundance ratios for their sources and find the largest (3He/H) abundance ratio is more than 10 times greater than their smallest limit. This observation gives strong support for source-to-source variations. There is a marginal tendency for sources outside the solar circle to have larger abundances. For the nine sources where 3He+ was detected, the average (3He/H) abundance ranges from 1.2 to 14.7×10-5 by number; for sources with limits, the lowest values are about 1×10-5. The authors discuss briefly the utility of 3He+ as a probe of cosmology or the chemical evolution of the Milky Way.
Bania et al. (Tue,) studied this question.