An Infrared Perspective on Cosmic Star Formation
Caitlin Casey
Institute for Astronomy, University of Hawai'i
Whether many of the Universe's stars are formed in galaxy mergers or quiescent, secularly evolving disk galaxies is fiercely debated. Whatever the formation mechanism, about half of all star formation activity is emitted in the infrared by dusty galaxies. Observing the most luminous star-forming galaxies -- galaxies which are rare but produce huge numbers of stars very rapidly -- provides an important method of studying galaxy evolution and the stellar mass assembly of the early Universe. Infrared observations are uniquely useful since they probe star formation directly, as seen from dust-reprocessed emission of ultraviolet light from young stars. I will describe some of the latest research surrounding infrared-luminous starburst galaxies, from low to high redshift, and present some of the conundrums of the field (from sample selection biases, observational limitations, to disagreements over galaxies' evolution). With a plethora of new observational tools just becoming available in the infrared and sub-millimeter (e.g. Herschel Space Observatory, SCUBA2, and ALMA), distant galaxies will soon be studied in exquisite detail in both dust and gas, filling in gaps of information which cannot be answered by detailed studies of their stellar emission. Our eventual goal is to reach an understanding of the triggering mechanisms for star formation episodes in extreme, ultraluminous starburst environments, how they relate to star formation in more common "Milky Way" type galaxies at high-redshift, and what the implications are for galaxy evolution today.
Date: Mercredi, 13 mars 2013 Time: 10:30 Where: Université de Montréal Pavillon Claire-McNicoll, local Z-337