Abstract
CCD images of a set of 52 bright barred spiral galaxies in the narrow band filter Hα and in the broadband I filter are presented. The sample was selected from the Shapley Ames Catalog, with IRAS fluxes characteristic of star formation and a dust temperature above Td >= 25 K. The study is aimed at identifying the global distribution and the underlying symmetries of the structures of ionized gas in barred galaxies. Thirty-two galaxies present Hα emission from the innermost central regions, but the emission from nuclear rings is observed only in ten galaxies. About half of the observed galaxies show Hα emission from several regions in the disk, and 18 galaxies display emission from along the bar. The Hα emission from inner and outer rings are easily identified in some galaxies. Some other galaxies present a more complicated spatial distributions, probably due to tidal or direct encounters with neighboring galaxies.
