Disk Material Inflates Gaia RUWE Values in Single Stars

Abstract An understanding of the dynamical evolution binary star systems, and their effects on stellar planetary evolution, requires well-characterized populations across ages. However, observational resources required to find characterize binaries are expensive. With release high-precision Gaia astrometry, re-normalized unit weight error (RUWE) statistic has been shown reveal presence with RUWE values greater than 1.2 indicating a companion within ∼1″. Our goal is assess whether this new diagnostic, which was developed for field-age systems (>1 Gyr), applies young systems; specifically, those that host circumstellar disks. control sample single-star compiled from high-contrast imagining surveys Taurus Upper Scorpius star-forming regions, we compare without We show protoplanetary disk alone can result in inflated values. Based distribution disk-bearing single stars, suggest more conservative single-star—binary threshold warranted material. place cutoff at distribution’s 95th percentile, = 2.5.