The recent cluster formation histories of NGC 5253 and NGC 3077: Environmental impact on star formation

We present multicolor photometry of bright star cluster candidates in the nearby starburst galaxies NGC 3077 and NGC 5253, observed with the Hubble Space Telescope Wide Field Planetary Camera 2 in both broadband (F300W, F547M, and F814W) and narrowband (F487N and F656N) filters. By comparing the photometry with theoretical population synthesis models, we estimate the age and mass of each star cluster, which provides constraints on the recent star formation histories of the host galaxies. We compare the star cluster populations in these dwarf starburst galaxies with those of the nuclear starburst in the barred spiral M83 and discuss the implications for our understanding of the nature and evolution of starburst events.