Southern HII Region Discovery Survey. II. Full cat

For this data release, we reprocess all previously published SHRDS data and include an additional ~450hr of observations. The search for new HII regions is now complete over the range 259{deg}<l<346{deg}, |b|<4{deg} for HII region candidates with predicted 6GHz continuum peak brightnesses >~30mJy/beam.

We detect radio continuum emission toward 730 targets altogether including previously known nebulae and HII region candidates. By averaging ~18 RRL transitions, we detect RRL emission toward 206 previously known HII regions and 436 HII region candidates. Including the northern sky surveys, over the last decade the HII Region Discovery Surveys have more than doubled the number of known Galactic HII regions.