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arXiv · 2004.03135

GW Ori: Interactions Between a Triple-star System and its Circumtriple Disk in Action

Jiaqing Bi·Nienke van der Marel·Ruobing Dong·Takayuki Muto·Rebecca G. Martin·Jeremy L. Smallwood·Jun Hashimoto·Hauyu Baobab Liu·Hideko Nomura·Yasuhiro Hasegawa·Michihiro Takami·Mihoko Konishi·Munetake Momose·Kazuhiro D. Kanagawa·Akimasa Kataoka·Tomohiro Ono·Michael L. Sitko·Sanemichi Z. Takahashi·Kengo Tomida·Takashi Tsukagoshi
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Abstract

GW Ori is a hierarchical triple system which has a rare circumtriple disk. We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of 1.3 mm dust continuum and 12CO J=2-1 molecular gas emission of the disk. For the first time, we identify three dust rings in the disk at ~46, 188, and 338 AU, with estimated dust mass of ~70-250 Earth masses, respectively. To our knowledge, the outer ring in GW Ori is the largest dust ring ever found in protoplanetary disks. We use visibility modelling of dust continuum to show that the disk has misaligned parts and the innermost dust ring is eccentric. The disk misalignment is also suggested by the CO kinematics modelling. We interpret these substructures as evidence of ongoing dynamical interactions between the triple stars and the circumtriple disk.

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Jiaqing Bi, Nienke van der Marel, Ruobing Dong, Takayuki Muto, Rebecca G. Martin, Jeremy L. Smallwood, Jun Hashimoto, Hauyu Baobab Liu, Hideko Nomura, Yasuhiro Hasegawa, Michihiro Takami, Mihoko Konishi, Munetake Momose, Kazuhiro D. Kanagawa, Akimasa Kataoka, Tomohiro Ono, Michael L. Sitko, Sanemichi Z. Takahashi, Kengo Tomida, Takashi Tsukagoshi. 2020-04-07. GW Ori: Interactions Between a Triple-star System and its Circumtriple Disk in Action. https://doi.org/10.3847/2041-8213%2Fab8eb4

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