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arXiv · 2109.06128

Modeling of CO ro-vibrational line emission of HD 141569

Stanley K. Jensen Jr.·Sean D. Brittain·Joan R. Najita·John S. Carr
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Abstract

HD 141569 is a Herbig Ae/Be star that straddles the boundary between the transition disks and debris disks. It is a low dust mass disk that reveals numerous structural elements (e.g. gaps and rings) that may point to young planets. It also exhibits a reservoir of CO gas observed at both millimeter and IR wavelengths. Previous observations (Goto et al. 2006) reported a possible asymmetry in the CO gas emission. Herein the IR ro-vibrational emission lines are analyzed and modeled both spectroscopically and spectroastrometrically. We find emission features from both 12CO and 13CO isotopologues heated to a temperature of approximately 200 K in the radial extent of 13 to 60 au. We do not see evidenceof the previously reported asymmetry in CO emission, our results being consistent with a Keplerian, axisymmetric emitting region. This raises the question of whether the emission profile may be evolving in time, possibly as a result of an orbiting feature in the inner disk such as a planet.

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Stanley K. Jensen Jr., Sean D. Brittain, Joan R. Najita, John S. Carr. 2021-09-13. Modeling of CO ro-vibrational line emission of HD 141569. https://doi.org/10.1088/1538-3873%2Fac21a2

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