Collaborative Research: The Last of FIRST: Completing Our View of the Radio Universe

University Of California-Davis, Davis CA

Investigators

Abstract

Collaborative Research: The Last of First: Completing Our View of the Radio Universe" AST-0098355 A ten-year program to use the world's most powerful radio telescope to provide Faint Images of the Radio Sky at Twenty-cm (FIRST) is nearing its goal of mapping the entire northern sky outside the Milky Way with a resolution and sensitivity that exceed previous surveys by a factor of fifty or more. Over three-quarters of a million radio emitters have been detected to date, ranging from nearby active stars to the most distant quasars known. The images and source catalogs are all available on the World-Wide Web, and have been used to date by more than three hundred astronomers. The FIRST team is pursuing a number of major projects with this massive new database. Matching the radio catalog to the near-infrared sources cataloged by the 2MASS survey, they have discovered a number of highly obscured quasars -- objects emitting a thousand times the energy of the whole Milky Way from a tiny region in a distant galaxy core that is so dust-ridden that no visible light escapes. Another major project is using the entire set of radio images to attempt to determine the distribution of the mysterious dark matter in the Universe. Recognizing Einstein's dictum that mass bends light, they look for the slight distortions in the shapes of distant radio galaxies caused by the passage of their radio waves through the mass distribution of the intervening space. While optical astronomers have been conducting such "weak lensing" experiments on patches of sky the size of the full moon and smaller, this research will study the clumpiness of the dark matter on scales ten to one hundred times larger, thus making a direct connection between the galaxy distribution in the local Universe and the fluctuations seen in the cosmic background radiation which tells us the distribution of matter at the earliest times.