The Supernova Survey for the Roman Space Telescope

The Roman Space Telescope is a NASA flag ship mission, due to be launched in the mid-2020’s. One of the mission’s goals is to help us to understand the nature of dark energy through the examination and study of multiple cosmological probes, including Type Ia supernovae (SNe Ia), which will be observed through a dedicated SN survey. This survey is expected to take six months of observing time over a two-year period. Roman’s Wide Field Imager has several broad-band filters from the optical to the near infrared and a prism/grisms for slitless spectroscopy over its 0.28 deg² field of view, all of which are accessible for the SN survey. The combination of wide field and NIR sensitivity is unique to Roman’s design and allow for the first large-scale high-redshift infrared SN survey. In this poster we present a baseline supernova survey strategy which consists of shallow-wide and deep tiers for both imaging and spectroscopy. The relative depths and areas of the tiers are designed to have a flatter redshift distribution extending up to and beyond z=2. The cadence of the survey will be five days with approximately 30 hours per visit. Within this baseline survey strategy variations are available, such as the ratio of time devoted to prism spectroscopy vs. imaging, the number and choice of filters per imaging tier (the baseline starts with four filters for each tier, with redder filters for the deeper tier), how best to include photometric redshifts, and how best to coordinate and incorporate information from other surveys occurring during the Roman era. We will discuss the supernova studies and planning studies over the upcoming years that will have bearing on the settings of these variations that are employed during the survey.