SO Webloquio: Star-forming Complexes in Local Mergers and High Redshift Galaxies

Disk galaxies at high redshift contain star-forming complexes, or clumps, whose masses and sizes far exceed those of clumps in local non-interacting galaxies. However, our recent Hubble Space Telescope observations reveal that local merging galaxies can form massive clumps like those at high z, with the same range of physical size, surface density, age, and star formation rate. These similarities, combined with the loss at high redshift of low surface brightness merger signatures such as tidal tails due to cosmological dimming, suggest that some clumpy high-z galaxies that appear isolated could be mergers. We find that giant clumps in local mergers contain many star clusters, with a range of ages and with standard luminosity functions. We infer from this that high redshift clumps contain (unresolved) normal bound clusters also, as a consequence of a hierarchy of star formation.

30/03/2021 - 12:30
Dr. Debra Elmegreen
Vassar College, NY, USA