X-Shooter acc disc properties of Sco-Cen stars

Studies of nearby star-forming regions of different ages and properties provide the information needed to understand the processes governing their evolution. This paper presents the results of a spectroscopic study of the stellar and accretion properties of a large sample of 127 stars with protoplanetary discs in the Upper Scorpius region, a relatively old (5-10Myr), nearby (~145pc) star-forming region, with disc dust masses inferred from ALMA continuum measurements.

We derived the accretion luminosity from the excess UV continuum emission with respect to the photospheric and chromospheric emission self-consistently with the stellar spectral types, extinction, and luminosity, using the FitteR for Accretion ProPErties of T Tauri stars (FRAPPE) code. We applied a new method to evaluate upper limits on the accretion luminosity. In ~50% of cases, we could only evaluate upper limits on the accretion luminosity, either because the signal-to-noise ratio of the data was insufficient or because the measured value of the accretion luminosity was below the statistical estimate of the emission due to chromospheric activity.