New Results from the Cosmic Origins Spectrograph: Missing Baryons, AGN, and Reionization Epochs of H and He

Colloquium: Astronomy Colloquia | November 8 | 4 p.m. | 2 LeConte Hall

Speaker/Performer: Michael Shull, University of Colorado

Sponsor: Department of Astronomy

I present a survey of recent ultraviolet spectroscopic observations with the Cosmic Origins Spectrograph, installed on the Hubble Space Telescope in May 2009. I will describe the current status of the local baryon census, observations and theoretical modeling of thermal phases of the intergalactic medium (IGM) and circumgalactic medium (CGM), and the extent of heavy element transport away from galaxy halos. Other new results include the COS composite UV spectrum of quasars, measurements of metal reservoirs in galactic halos, and probes of the Helium-II epoch of reionization at redshifts z = 2.5 to 3.3. We have also used COS "parallel observations" with the new Wide-Field Camera-3 to discover galaxies at z = 8, likely responsible for the IGM reionization of hydrogen.

Event Contact: rhelgens@astro.berkeley.edu, 510-642-5275