# An Intensive HST Survey for z>1 Supernovae by Targeting Galaxy Clusters

## TL;DR

This paper introduces a targeted HST survey strategy focusing on galaxy clusters at z>0.9 to efficiently discover high-redshift Type Ia supernovae, reducing systematic uncertainties in cosmological measurements.

## Contribution

The study demonstrates that targeting galaxy clusters significantly improves the efficiency and yield of high-redshift SN discoveries compared to field surveys.

## Key findings

- Discovered 16 SNe at z>0.95, including 9 in galaxy clusters.
- Achieved twofold increase in SN detection efficiency.
- Reduced systematic uncertainties in SN cosmology.

## Abstract

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<z<1.5, we obtain a twofold improvement in the efficiency of finding SNe compared to an HST 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.