Multi-epoch Direct Imaging and Time-Variable Scattered Light Morphology of the HD 163296 Protoplanetary Disk
Abstract
We present H-band polarized scattered light imagery and JHK high-contrast spectroscopy of the protoplanetary disk around HD 163296 observed with the HiCIAO and SCExAO/CHARIS instruments at Subaru Observatory. The polarimetric imagery resolve a broken ring structure surrounding HD 163296 that peaks at a distance along the major axis of 0.65 (66 AU) and extends out to 0.98 (100 AU) along the major axis. Our 2011 H-band data exhibit clear axisymmetry, with the NW- and SE- side of the disk exhibiting similar intensities. Our data are clearly different than 2016 epoch H-band observations from VLT/SPHERE that found a strong 2.7x asymmetry between the NW- and SE-side of the disk. Collectively, these results indicate the presence of time variable, non-azimuthally symmetric illumination of the outer disk. Based on our 3D-MCRT modeling of contemporaneous IR spectroscopic and H-band polarized intensity imagery of the system, we suggest that while the system could plausibly host an inclined inner disk component, such a component is unlikely to be responsible for producing the observed time-dependent azimuthal variations in the outer scattered light disk of the system. While our SCExAO/CHARIS data are sensitive enough to recover the planet candidate identified from NIRC2 in the thermal IR, we fail to detect an object with a corresponding JHK brightness estimated from the atmospheric models of Baraffe et al. 2003. This suggests that the candidate is either fainter in JHK bands than model predictions, possibly due to extinction from the disk or atmospheric dust/clouds, or that it is an artifact of the dataset/data processing. Our SCExAO/CHARIS data lower the IR mass limits for planets inferred at larger stellocentric separations; however, these ALMA-predicted protoplanet candidates are currently still consistent with direct imaging constraints.
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Cite
@article{arxiv.1811.07785,
title = {Multi-epoch Direct Imaging and Time-Variable Scattered Light Morphology of the HD 163296 Protoplanetary Disk},
author = {Evan A. Rich and John P. Wisniewski and Thayne Currie and Misato Fukagawa and Carol A. Grady and Michael L. Sitko and Monika Pikhartova and Jun Hashimoto and Lyu Abe and Wolfgang Brandner and Timothy D. Brandt and Joseph C. Carson and Jeffrey Chilcote and Ruobing Dong and Markus Feldt and Miwa Goto and Tyler Groff and Olivier Guyon and Yutaka Hayano and Masahiko Hayashi and Saeko S. Hayashi and Thomas Henning and Klaus W. Hodapp and Miki Ishii and Masanori Iye and Markus Janson and Nemanja Jovanovic and Ryo Kandori and Jeremy Kasdin and Gillian R. Knapp and Tomoyuki Kudo and Nobuhiko Kusakabe and Masayuki Kuzuhara and Jungmi Kwon and Julien Lozi and Frantz Martinache and Taro Matsuo and Satoshi Mayama and Michael W. McElwain and Shoken Miyama and Jun-Ichi Morino and Amaya Moro-Martin and Takao Nakagawa and Tetsuo Nishimura and Tae-Soo Pyo and Eugene Serabyn and Hiroshi Suto and Ray W. Russel and Ryuji Suzuki and Michihiro Takami and Naruhisa Takato and Hiroshi Terada and Christian Thalmann and Edwin L. Turner and Taichi Uyama and Kevin R. Wagner and Makoto Watanabe and Toru Yamada and Hideki Takami and Tomonori Usuda and Motohide Tamura},
journal= {arXiv preprint arXiv:1811.07785},
year = {2019}
}
Comments
19 pages, 13 figures, 2 tables