THE HUBBLE HIGHER-z SUPERNOVA SEARCH: SUPERNOVAE TO z ≈ 1.6 AND CONSTRAINTS ON TYPE Ia PROGENITOR MODELS a a BASED ON OBSERVATIONS WITH THE NASA/ESA HUBBLE SPACE TELESCOPE, OBTAINED AT THE SPACE TELESCOPE SCIENCE INSTITUTE, WHICH IS OPERATED BY AURA, INC., UNDER NASA CONTRACT NAS 5-26555

We present results from the Hubble Higher-z Supernova Search, the first space-based open field survey for supernovae (SNe). In cooperation with the Great Observatories Origins Deep Survey, we have used the Hubble Space Telescope with the Advanced Camera for Surveys to cover ∼ 300 square arcmin in the area of the Chandra Deep Field South and the Hubble Deep Field North on five separate search epochs (separated by ∼ 45 day intervals) to a limiting magnitude of F850LP ≈ 26. These deep observations have allowed us to discover 42 SNe in the redshift range 0.2 95% confidence. We find that Gaussian models best fit the observed data for mean delay times in the range of 3 to 4 Gyr.