Radial decoupling of small and large dust grains in the transitional disk RX J1615.3-3255

Robin Kooistra, Inga Kamp, Misato Fukagawa, François Ménard, Munetake Momose, Takashi Tsukagoshi, Tomoyuki Kudo, Nobuhiko Kusakabe, Jun Hashimoto, Lyu Abe, Wolfgang Brandner, Timothy D. Brandt, Joseph C. Carson, Sebastian E. Egner, Markus Feldt, Miwa Goto, Carol A. Grady, Olivier Guyon, Yutaka Hayano, Masahiko Hayashi, Saeko S. Hayashi, Thomas Henning, Klaus W. Hodapp, Miki Ishii, Masanori Iye, Markus Janson, Ryo Kandori, Gillian R. Knapp, Masayuki Kuzuhara, Jungmi Kwon, Taro Matsuo, Michael W. McElwain, Shoken Miyama, Jun-Ichi Morino, Amaya Moro-Martin, Tetsuo Nishimura, Tae-Soo Pyo, Eugene Serabyn, Takuya Suenaga, Hiroshi Suto, Ryuji Suzuki, Yasuhiro H. Takahashi, Michihiro Takami, Naruhisa Takato, Hiroshi Terada, Christian Thalmann, Daigo Tomono, Edwin L. Turner, Makoto Watanabe, John Wisniewski, Toru Yamada, Hideki Takami, Tomonori Usuda, Motohide Tamura, Thayne Currie, Eiji Akiyama, Satoshi Mayama, Katherine B. Follette, Takao Nakagawa

We present H-band (1.6 μm) scattered light observations of the transitional disk RX J1615.3-3255, located in the 1 Myr old Lupus association. From a polarized intensity image, taken with the HiCIAO instrument of the Subaru Telescope, we deduce the position angle and the inclination angle of the disk. The disk is found to extend out to 68 ± 12 AU in scattered light and no clear structure is observed. Our inner working angle of 24 AU does not allow us to detect a central decrease in intensity similar to that seen at 30 AU in the 880 μm continuum observations. We compare the observations with multiple disk models based on the spectral energy distribution (SED) and submm interferometry and find that an inner rim of the outer disk at 30 AU containing small silicate grains produces a polarized intensity signal which is an order of magnitude larger than observed. We show that a model in which the small dust grains extend smoothly into the cavity found for large grains is closer to the actual H-band observations. A comparison of models with different dust size distributions suggests that the dust in the disk might have undergone significant processing compared to the interstellar medium.

Astronomy & Astrophysics

EDP Sciences

597

A132

10.1051/0004-6361/201628696