Distributions, equivalent widths and metallicities of the H II regions in the spiral galaxies NGC 5457 and NGC 4395

Using CCD observations in the narrow band filters in Hα ,H β ,( O), (O ), (S  )a nd (S) lines we have compiled a catalogue of 338 H  regions for the inner parts of NGC 5457 and 158 for NGC 4395. The extinction, equivalent widths, distributions, excitations, ionization hardness, ionization parameters and metallicities for these regions, a distinction being made between arm and inter-arm zones, are presented here with the first results of a study of stellar formation.

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