THE LUMINOSITY FUNCTION AND SIZE DISTRIBUTION OF THE H II REGIONS IN M33

We present Hα fluxes and sizes for most of the H 2 regions in M33 listed in the catalog of Courtès et al. (1987). The observed bright end of the differential luminosity function is approximately a power law with exponent a = -2.40 ± 0.15, while the number counts turn over at an Hα luminosity of approximately 1036.4 erg s-1. After accounting for the effects of incompleteness in our sample, we find that the faint end of the corrected luminosity function remains almost constant instead of turning over. The cumulative size distribution approximately follows an exponential law with scale size D0 = 32 ± 1 pc. We briefly discuss the implications of our results for our understanding of recent high-mass star formation in M3.