We have used images from the Advanced Camera for Surveys on the Hubble Space Telescope in H{alpha}, and in the neighboring continuum, to produce flux-calibrated images of the large spiral galaxy M51 and the dwarf irregular NGC 4449. From these images, we have derived the absolute luminosities in H{alpha}, the areas, and the positions with respect to the galactic centers as reference points of over 2600 HII regions in M51 and over 270 HII regions in NGC 4449.
Cone search capability for table J/AJ/141/113/table2 (Brightest HII regions in M51)
Cone search capability for table J/AJ/141/113/table3 (Brightest HII regions in NGC 4449)