Target Selection and Observation Modeling Tools for the Roman Coronagraph Technology Demonstration and Beyond

Dmitry Savransky / Cornell University, PI

The Space Imaging and Optical System Laboratory (SIOSlab) at Cornell University has been actively supporting the Nancy Grace Roman Space Telescope Coronagraph Instrument since pre-Phase A activities. We currently maintain two open-source, community resources: a one-to-one port of the internal JPL Exposure Time Calculator (ETC) for the Roman coronagraph (available as a module of the publicly distributed EXOSIMS software framework) and a publicly accessible database of known planetary companions that could potentially be imaged by the Roman coronagraph (the Imaging Mission Database). We propose a suite of activities under the Coronagraph Community Participation Program aimed to further develop and expand both of these resources, and specifically targeting topic areas A (modeling of astrophysical targets), B (selecting suitable observing targets), D (planning observations) and M (enabling activities for possible further use of the coronagraph).

Specifically, we will continue development and maintenance of the EXOSIMS Roman coronagraph ETC to account for improvements in the instrument model and new characterizations of the flight instrument. For each ETC update, we will recompute detection probabilities for all targets in the Imaging Mission Database. The database will also continuously be updated with new targets as they are discovered, and with new orbital fits for current targets as they appear in the literature. We will augment the existing photometric model grids used in the database to provide better predictions of known planet detection probabilities with the coronagraph, and will add optimal observation times for all targets observable by the coronagraph. Optimal observing times will be computed by applying new methodologies, recently published by our group, for the use of radial velocity data to optimize imaging observations. We will also expand these methodologies to work with all relevant targets in the database. Finally, we will continue development of the EXOSIMS blind search simulation capabilities for the Roman coronagraph to prepare for any potential science program following a successful technology demonstration, and similarly update the blind search (and unknown companion) search targets in the database.

In addition to these specific activities, the PI and members of the proposing team have broad expertise and experience in coronagraphic exoplanet imaging and instrumentation, and could support multiple other activities, as required by the final makeup of the CPP team.