Boston University HII Region Catalog

This catalog contains all 298 Galactic HII regions with measured radio recombination lines over the extent of the Galactic Ring Survey (l = 15-57°, |b| ≤ 1°. We compiled this catalog from the catalogs of ultra compact (UC) regions (Araya et al. 2002, Watson et al. 2003, Sewilo et al. 2004), classical regions (Lockman 1989), and regions that are truly diffuse (Lockman, Pisano, & Howard 1996). All sources were verified as being HII regions based on the infrared (MIPSGAL and GLIMPSE) and 20cm continuum (MAGPIS) emission.