Astronomy Seminar: "Supernova Cosmology: From DES to Roman"

Benjamin Rose (Duke University)
- | David Rittenhouse Laboratory, 4C6

The Dark Energy Survey (DES) is in the process of finalizing its ultimate scientific analyses. Later this year, we expect the DES Supernova survey to release a constraint on the dark energy equation of state to less than 3%. This will be the most precise measurement of dark energy using Type Ia Supernovae (SN Ia). These results are systematic uncertainty dominated, meaning a more precise measurement requires more than simply continuing to collect data. NASA's Nancy Grace Roman Space Telescope, to be launched before mid 2027, has a mission goal of measuring dark energy approximately two times better than DES. Supernova cosmology with Roman will use the High Latitude Extragalactic Time Domain core community survey, and observe ~12,000 SNe Ia with most of them being above a redshift of one. In addition to this large data set, Roman will need to control both hardware and astrophysical systematics. In this talk, I will explain the current efforts to ensure Roman's calibration as well as improved analysis models and methods will allow Roman to make this extremely precise measurement of dark energy.