In the early universe, star formation is dominated by the most massive galaxies with stellar masses of 1012 M. Evidence for high density environments around massive galaxies may be crucial in understanding the rapid formation of their stellar population. We have begun a search for high redshift (z > 2) radio galaxies in the Southern Hemisphere, based on ultra-steep spectrum selection from the 408 MHz Revised Molonglo Reference Catalogue (MRCR), the 843 MHz Sydney University Molonglo Sky Survey (SUMSS) and the 1400MHz NRAO VLA Sky Survey (NVSS). Using very deep optical to near-infrared imaging, we have investigated the role of environmental density on the evolution of the galaxies that lie at z = 2 - 3.5, the epoch in which the overall star formation rate in the universe was at a peak.
展开▼
