Dr. Wilson and his team will carry out a research program to analyze and understand recent data taken with their 1mm wavelength bolometer camera (called AzTEC) to measure millimeter continuum dust emission from submillimeter galaxies (SMGs) within, or lensed by, galaxy clusters in the COSMOS field (a region of the sky that has been studied extensively at many wavebands). This is the largest survey to date of the SMG population. The team will study hierarchical structure formation and evolution via the evolution of the SMG population in cluster environments. The work will utilize panchromatic observations resulting from a number of radio, millimeter, and optical telescopes. The resulting dataset will guide numerical simulations and semi-analytic structure formation theories. The project will also map the small-scale Sunyaev-Zeldovich emission in a suite of large clusters in order to quantify the importance of mergers.
Distant galaxies discovered in maps of the sky made at millimeter and submillimeter wavelengths (hereafter "submm galaxies" or SMGs) are some of the most massive and prolific galaxies in the Universe and yet, because of their extreme dust content, are extremely difficult to detect with optical telescopes such as the Hubble Space Telescope and the Keck telescopes. In this sense, observations of these galaxies open an entirely new view of the different populations of galaxies present in our Universe. The primary goals of our project were to 1) analyze a series of deep images of the mm-wavelength sky made with the AzTEC camera in order to detect the population of SMGs, 2) characterize the detected SMG population in a statistical sense using far more galaxies than any previous study, 3) characterize individual galaxies in the population via their emission at other wavelengths, 4) characterize the population as a function of the environment they were found in (that is, high galactic density regions of the Universe vs. low galactic density regions) and 5) to use these same images to study the diffuse gas inhabiting clusters of galaxies. Overall we made great progress in all these goals with substantial intellectual merit. During the project period we produced the tightest constraints ever made on the numbers of SMGs found in each area of the sky – in both low and high density regions – forcing theoreticians to re-think their models of SMG formation. In two widely publicized studies we discovered clusters of SMGs in the very early Universe – again, pushing theoretical models of galaxy formation to account for our data. We have characterized the contamination by SMGs to important experiments studying the Dark Energy in our Universe and we have published new statistical methods for constraining galaxy parameters. The broader impacts of our work have also been substantial. By providing our source catalogs to the public in our publications, we have allowed many addition studies of the SMG population by other astronomers and at complementary facilities. Our largest map of the COSMOS field was made public to the COSMOS and Herschel survey groups and will eventually be made public to the wider astronomy community. Finally, our new statistical software suite for honestly characterizing galaxy parameters based on observations at different wavelengths, SATMC, has been made available to the astronomical community through a public astronomy software sharing site.
