Star formation in the center of spiral galaxy ngc 4736

We estimate the star formation properties of the center and circumnuclear ring of spiral galaxy NGC 4736 (M94) using its population of observed young star clusters. We use Hubble Space Telescope (HST) observations to identify clusters in the center and the ring. We compare the observed photometry of the sources in our cluster catalog to those predicted by stellar evolutionary models to estimate masses, M , ages, τ , and extinctions, AV , for each. We observe the mass function of clusters in the ring and center to both be well-approximated by a power law function, dN/d logM ∝ M with β ∼-1.8. We use masses extrapolated from these mass functions to estimate the star formation rates (SFR) in a 100 Myr timescale. We find the surface density of star formation, ΣSFR to be about 7 times as high in the ring as in the center, despite very similar surface gas densities, Σgas. Subject headings: galaxies: individual: NGC 4736 – galaxies: starburst – galaxies: star clusters: general – stars: formation