How The Inner Disk Communicates to the Outer Disk

Abstract

We investigated how evolution in the outer disk has an influence on the inner disk of a protoplanetary disk system. Thanks to two‐layer models that give the theoretical platform of disk geometry, we now have a good handle on how dust evolves in outer protoplanetary disks (>10 AU). It has long been thought that the outer and inner disks dissipate on roughly the same time scale as sub‐mm observations of nearby T Tauri systems has suggested. However, new high spatial resolution observations point toward the dissipation of an inner disk as not being a simple extension of the outer disk. We performed preliminary tests of the differential disk evolution in gas and dust in the inner disks of Herbig Ae/Be stars using the CO vibrational band as the gas probe. The line luminosity of CO v = 1−0 P(30) has a reasonable correlation with the near‐infrared excess over the stellar photosphere. It guarantees that the CO vibration band is a secure probe of the inner disk, as is expected from its high critical density, high ...