IAU Symposium Abstract S186-088P

Galaxy Collision induced Starburst Arcs and Rings: Models and Observations compared.

Susan A. Lamb1
1 University of Illinois, Urbana, Illinois, USA < slamb@astro.uiuc.edu >

Optically identified collisionally produced 'ring-galaxies' usually display vigorous star formation in an expanding ring or arc of high density gas. This star formation dominates the appearance of these galaxies, the nucleus often being faint and sometimes not observed at optical wavelengths. Near-infrared images show that the older stellar disk population has also been swept into an outwardly expanding density/material wave. We compare our numerical models for these types of galaxy systems with observational data and obtain valuable information on timescales and the global dynamics of the collision. Further, we compare observations of star forming regions in interacting galaxies with the corresponding physical characteristics of the stars and gas in the models. In this way we can further our understanding of the parameters that determine the characteristics of global star formation in these and other density wave driven star forming systems. The results may be applicable to the interpretation of the bright star-forming arcs and rings observed in high-redshift clusters of galaxies.