Program: GS-2008B-Q-26

We propose to observe a sample of low luminosity host galaxies of Type Ia supernovae using the GMOS-S spectrograph in order to obtain high-precision redshift measurements as well as information about the nature of supernova environments. The Nearby Supernova Factory (SNfactory) is working to anchor the low redshift end of the SN Ia Hubble diagram in the nearby smooth Hubble flow with observations of a large number of SNe Ia. The SNfactory uses an impartial search technique, and thus finds many SNe Ia in low luminosity galaxies, most of which have previously unknown redshifts. The typical low metallicity of low luminosity galaxies suggests the environments of SNe in these galaxies will be the most similar to those of SNe at higher redshifts, making their study important for future high-redshift SN programs. Redshifts from host galaxy spectra will facilitate the construction of the most accurate Hubble diagram to date, while the spectra themselves will allow us to probe the environments of the SNe in our sample.