High-resolution UKIRT observations of circumnuclear star formation in M100

We present high-resolution, near-infrared imaging of the circumnuclear regi on of the barred spiral galaxy M100 (NGC 4321), accompanied by near-infrare d spectroscopy. We identify a total of 43 distinct regions in the K-band im age, and determine magnitudes and colours for 41 of them. By comparison wit h other near-infrared maps we also derive colour excesses and K-band extinc tions for the knots. Combining the imaging and spectroscopic results, we co nclude that the knots are the result of bursts of star formation within the last 15-25 Myr. We discuss the implications of these new results for our d ynamical and evolutionary understanding of this galaxy.