A Flexible Open-Source Framework for Rapid Stellar Classification in the Era of Roman

PI: Zucker, Catherine, Smithsonian Institution/Smithsonian Astrophysical Observatory
Wide-Field Science – Regular

All three Roman Core Community Surveys and the first announced General Astrophysics Survey (the Galactic Plane Survey) are together expected to obtain multi-band photometry for tens of billions of stars, constituting an order of magnitude more stars than all other existing surveys combined. The Roman photometry will enable stellar classification en masse across the Galactic disk and halo, underpinning a broad range of science investigations in Galactic structure, star formation, stellar populations, galaxy evolution, and exoplanet demographics. We propose to add Roman-centric functionality to a publicly available open-source stellar classification package called brutus, which has already been validated on a billion stars in the Galactic disk and halo. Using brutus, the community will be able to i) infer the stellar type, distance, and extinction of any star with multi-band photometry in Roman ii) generate synthetic photometry in the Roman filters as a function of stellar type and Galactic environment, and iii) evaluate the impact of number/choice of Roman filters on stellar parameter recovery to inform future Roman survey designs. To accomplish these objectives, we plan to incorporate the Roman filters alongside a suite of complementary filters from synergistic facilities, augment the range of stellar models to capture more diverse stellar populations, and incorporate a proper motion prior (alongside the photometry) to dramatically reduce errors on stellar parameter recovery. The key deliverable will be a new release of the brutus software with full documentation and accompanying tutorials that will enable the community to squeeze the maximum amount of information possible from the Roman photometry and astrometry, both in terms of planning observations and when processing future archival data.