Deciphering the Cosmic Infrared Background

California Institute Of Technology, Pasadena CA

Investigators

Abstract

Among the potentially most important results of cosmology in the last decade is the realization that the star formation rate at redshifts z > 1 is higher than at present by about an order of magnitude, and that half of the energy produced since the surface of last scattering has been absorbed and reemitted by dust. Most of the light produced by stars at high redshift thus reaches us in the far infrared. This radiation is referred to as the cosmic infrared background (CIB) and is emitted primarily by dusty, star-forming galaxies at z = 1-3. Embedded in far infrared emission of the CIB is the history of star formation, dust production, and the growth of large scale structures. Most lately, several new observational projects (ACT, SPT, Planck, Herschel) released their first measurements of the CIB. This award will support the development of the theoretical understanding required to make the best of these new observations. The work promises original insights into the high redshift star formation history of the universe, directly at a period where the star formation peaked. Since this period of galaxy evolution is hard to probe by any other means, the research will help address fundamental issues, such as: (1) the fossil record of galaxy assembly from the first stars to present, (2) the connections between dark and luminous matter, and (3) the formation and evolution of cosmic structures. The results from the research will be broadly disseminated in scientific journals, conferences and public media. The research team will also participate in numerous outreach projects via the Caltech Classroom Connection.