Wide-Field Science – Regular
Susana Deustua / National Institute of Standards & Technology, Co-PI
Establishing Infrared Flux Standards for Roman Wide Field Instrument Science
The Nancy Grace Roman Space Telescope (Roman) is NASA’s next large flagship mission scheduled for launch by 2027. Roman’s Wide Field Instrument (WFI) will have a large field of view (0.28 sq deg), providing Hubble-like sensitivity and resolution in the infrared enabling transformational investigations in cosmology, exoplanet science and general astrophysics. The core community surveys include a High Latitude Wide Area survey, a High Latitude Time Domain survey, and a Galactic Bulge Time Domain survey.
In order to meet Roman’s dark energy goals, a requirement on the design of the imaging component of the High Latitude Wide Area Survey is to enable accurate measurements of the color to less than 0.5% as well as precision photometry over 11 mag in brightness of 0.3% of thousands of Type Ia Supernovae, and accurate photometric redshifts of millions of galaxies. These observations will be used to measure the accelerated expansion of the universe and to better constrain the nature of dark energy. Further, synergies with ground-based programs like the LSST with the Rubin Observatory and with space-based observatories like Euclid, will also require high fidelity for accurate cross-mission calibration.
At present the principal limitation to achieving these requirements is the paucity of standard stars that are both well characterized and have NIST-traceable spectral energy distribution in the critical brightness range between about V = 14- 20 mag. We propose to use a combination of ground-based and space-based assets to conduct a multi-year campaign to establish several hundred flux standards with an accuracy of a few millimags that will help Roman meet its demanding photometric requirements that enable transformational science.