Vol. 568
In section 6. Interstellar and circumstellar matter

Gas content of transitional disks: a VLT/X-Shooter study of accretion and winds

Transitional disks are thought to be a late evolutionary stage of protoplanetary disks whose inner regions have been depleted of dust. Using X-Shooter broad band - UV to NIR - medium-resolution spectroscopy, the authors derive the stellar, accretion, and wind properties of a sample of 22 transitional disks chosen among the largest accretors. The analysis of these properties allows the authors to constrain the gas content in a region very close to the star (≲ 0.2 AU) that is not accessible with any other observational technique. They find that the accretion rates and wind properties of 80% of the transitional disks in their sample are comparable to those of classical T Tauri stars. These results suggest that there is a gas-rich inner disk in these strongly accreting transitional disks with a density similar to that of classical T Tauri disks, even though the dust has been cleared from that same region.