Presentation #628.16 in the session Future Missions and Instrumentation.
The Astro2020 Decadal Survey has recommended that NASA realize a large (~6 m aperture), space-based infrared/optical/ultraviolet (IR/O/UV) telescope capable of high-contrast (10-10) imaging and spectroscopy in order to search for biosignatures from ~25 habitable zone planets. Starting from the NASA ExEP Mission Star List (EMSL) for the Habitable Worlds Observatory (HWO), we construct a catalog of 164 nearby stars whose hypothetical Earth-analogs would be the most accessible for a direct-imaging survey of habitable zones with HWO. Our catalog includes 1744 stellar abundance measurements of 14 different elements, archival photometry in 18 bandpasses spanning far-UV to mid-IR wavelengths, variability metrics for 78 stars, X-ray detections for 41 stars, and flare rate estimates for 44 stars. Using the photometry obtained from the literature, we independently derive and verify stellar parameters by fitting the SEDs of all of the stars in the catalog. Using our catalog, we identify and discuss key areas of precursor science that will be necessary to inform HWO mission design trade studies. These include investigating the depth of previous planet searches for these systems, assessing the dynamical stability of exo-Earths in systems with previously known planets, and analyzing the effects of flares, high-energy flux, and stellar composition on potential habitability. This work is the first in a series of precursor science efforts that will maximize our knowledge of the most promising HWO targets.