9320049 Partridge The cosmic microwave background radiation (CBR) reaches us from a time near the Big Bang origin of the Universe. As a consequence, it encodes unique information about the physical properties of the early Universe and about the early evolution of structure within the Universe. A recent satellite detection of angular variations in the CBR has provided important clues to the origin and evolution of very large-scale structure in the cosmos. The research to be conducted in this award is a study of the CBR on smaller scales, better matched to the size of structures we see in the Universe today, such as galaxies and clusters of galaxies. The Principal Investigator will make a deep radio map of a region of the sky at microwave frequencies. This will be the most sensitive radio "portrait" of the sky ever made. He will study the same area using the Hubble Space Telescope and other instruments to provide complementary information. In particular, it is hoped this research will provide a much clearer picture of when and how galaxies formed. In addition this work will enable studies of the properties of foreground sources, including radio galaxies. These sources are of interest in their own right. In addition, their emission interferes with attempts to study the CBR itself. The observations will help astronomers characterize and minimize this interference. Undergraduate students will be fully involved in all the observations and analysis. The Principal Investigator is regarded as a leader in this research area. ***
