Mayama, S, Akiyama, E, Panic, O orcid.org/0000-0002-6648-2968 et al. (15 more authors) (2018) ALMA Reveals a Misaligned Inner Gas Disk inside the Large Cavity of a Transitional Disk. Astrophysical Journal Letters, 868 (1). ARTN L3. ISSN 2041-8205
Abstract
Pairs of azimuthal intensity decrements at near-symmetric locations have been seen in a number of protoplanetary disks. They are most commonly interpreted as the two shadows cast by a highly misaligned inner disk. Direct evidence of such an inner disk, however, remains largely illusive, except in rare cases. In 2012, a pair of such shadows were discovered in scattered-light observations of the near face-on disk around 2MASS J16042165-2130284, a transitional object with a cavity ~60 au in radius. The star itself is a "dipper," with quasi-periodic dimming events on its light curve, commonly hypothesized as caused by extinctions by transiting dusty structures in the inner disk. Here, we report the detection of a gas disk inside the cavity using Atacama Large Millimeter/submillimeter Array (ALMA) observations with ~0farcs2 angular resolution. A twisted butterfly pattern is found in the moment 1 map of the CO (3–2) emission line toward the center, which is the key signature of a high misalignment between the inner and outer disks. In addition, the counterparts of the shadows are seen in both dust continuum emission and gas emission maps, consistent with these regions being cooler than their surroundings. Our findings strongly support the hypothesized misaligned inner disk origin of the shadows in the J1604-2130 disk. Finally, the inclination of the inner disk would be close to −45° in contrast with 45°; it is possible that its internal asymmetric structures cause the variations on the light curve of the host star.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2018. The American Astronomical Society. All rights reserved. Uploaded in accordance with the publisher's self archiving policy. |
Keywords: | planetary systems; protoplanetary disks; stars: pre-main sequence |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Physics and Astronomy (Leeds) > Astrophysics (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 16 Jan 2019 13:43 |
Last Modified: | 18 Feb 2019 11:23 |
Status: | Published |
Publisher: | American Astronomical Society |
Identification Number: | 10.3847/2041-8213/aae88b |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:141091 |