We present a new survey strategy to discover and study high redshift Type Ia supernovae (SNe Ia) using the Hubble Space Telescope (HST). By targeting massive galaxy clusters at 0.9<zHST field survey and a factor of three improvement in the total yield of SN detections in relatively dust-free red-sequence galaxies. In total, sixteen SNe were discovered at z>0.95, nine of which were in galaxy clusters. This strategy provides a SN sample that can be used to decouple the effects of host galaxy extinction and intrinsic color in high redshift SNe, thereby reducing one of the largest systematic uncertainties in SN cosmology.
K.S. Dawson, et al, (Supernova Cosmology Project). An Intensive HST Survey for z>1 Supernovae by Targeting Galaxy Clusters. Astronomical Journal, Volume 138, Issue 5, pp. 1271-1283 (2009). DOI: 10.1088/0004-6256/138/5/1271.