Infrared interferometric observations of T Tauri stars

We present observations of several T Tauri stars using long baseline infrared interferometry from the Palomar Testbed Interferometer. The target sources, T Tau N, SU Aur, RY Tau and DR Tau, are all known to be surrounded by dusty circumstellar disks. The observations directly trace the inner regions (<1 AU) of the disk and can be used to constrain the physical properties of this material. For three of the sources observed, the size scale of the infrared emission is tenths of AU, which is considerably larger than predicted by flat disk models. We discuss the implications of these results for models of circumstellar material, in particular the recent theoretical work suggesting the presence of an extended vertical wall at the inner edge of the disk.