title: A SEEDs study of the transitional disk associated with RY Tau

authors: Hiro Takami, Jennifer L. Karr, Jun Hashimoto, Hyosun-Kim, Thomas Henning, Carol Grady, Ryo Kandori, John Wisniewski, Klaus W. Hodapp, the SEEDS team

abstract: We present observations of RY Tau by the SEEDs (Strategic Exploration of Exoplanets and DIsks) project with Subaru-HiCIAO. RY Tau is a young well-studied pre-main sequence star, associated with a relatively massive disk, an optical jet, and a scattering nebulosity due to a remnant of the envelope. Recent observations with radio interferometry have revealed the probable presence of a hole in the disk  at 1.3-mm with a radius of ~15 AU. This possibly results from ongoing planet formation, i.e. a protoplanet tidally interacting with the inner disk region. Such disks are called gtransitional disksh, however, RY Tau is atypical of the other transitional disks in that it (a) still drives a jet; and (b) has no evidence for a deficit of warm, thermal emission near 10 microns.
We have successfully obtained the distribution of polarization intensity (PI) and a lower limit of polarization in H-band (1.65 um). The observed distribution indicates that the PI flux is due to scattering on the surface of a geometrically thick disk, or perhaps an outflow cavity with a very large opening angle. In this talk we compare the observed PI distribution with Monte-Carlo simulations of the scattered light (see poster by Karr, Kim and Takami about the simulation code).