A High-resolution Optical Survey of Upper Sco: Evidence for Coevolution of Accretion and Disk Winds

Abstract

Magnetohydrodynamic (MHD) and photoevaporative winds are thought to play an important role in the evolution and dispersal of planet-forming disks. Here, we analyze high-resolution (Δ v ∼ 7 km s −1 ) optical spectra from a sample of 115 T Tauri stars in the ∼5–10 Myr Upper Sco association and focus on the [O i ] λ 6300 and H α lines to trace disk winds and accretion, respectively. Our sample covers a large range of spectral types and we divide it into warm (G0-M3) and cool (later than M3) to facilitate comparison with younger regions. We detect the [O i ] λ 6300 line in 45 out of 87 Upper Sco sources with protoplanetary disks and 32 out of 45 are accreting based on H α profiles and equivalent widths. All [O i ] λ 6300 Upper Sco profiles have low-velocity (centroid