The Evolution of the Cosmic Supernova Rates

Through a combination of deep wideeld imaging and near-IR spectroscopy, the NGST will be able to chart with unprecedented accuracy the evolution of cosmic structures after the `dark ages' (z < 5), when galaxies are thought to assemble and form the bulk of their stars. In particular, accurate measurements at all redshifts of the frequencies of Type II and Ia SNe could be used as a probe of the star formation and heavy element enrichment history of the universe, and improve our understanding of the intrinsic nature and age of the populations involved in SN explosions. The deep imaging programs targeted at eld galaxies and gravitational lenses will nd of order 20 Type II SN per 4 4 arcmin eld per year in the redshift range 2 < z < 5 (at peak brightness). The derived SN II number counts in the JKLM bands for SCDM and LCDM cosmological models show that NGST will be able to detect 75% 50% (respectively) of the supernovae occurring up to z = 15 in the J band. Follow-up spectroscopy at R = 300 for 200 candidates at AB = 28 29 mag will provide an adequate sample for constraining the nature of Type Ia progenitors and the evolution of the stellar birthrate in the Universe. ASWG DRM Proposal The Evolution of the Cosmic Supernova Rates Observing Summary: Target RA Dec KAB Con guration/mode Days N/A N/A NIR/SPEC 0 Grand total days 0 NOTE: The search for SNe is a by-product of the deep galaxy and gravitational lens surveys that are also part of the DRM.