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arXiv · 1804.02360

An inner warp in the DoAr 44 T Tauri transition disk

Simon Casassus·Henning Avenhaus·Sebastian Perez·Victor Navarro·Miguel Carcamo·Sebastian Marino·Lucas Cieza·Sascha P. Quanz·Felipe Alarcon·Alice Zurlo·Axel Osses·Fernando R. Rannou·Pablo E. Romaan·Marcelo Barraza
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Abstract

Optical/IR images of transition disks (TDs) have revealed deep intensity decrements in the rings of HAeBes HD142527 and HD100453, that can be interpreted as shadowing from sharply tilted inner disks, such that the outer disks are directly exposed to stellar light. Here we report similar dips in SPHERE+IRDIS differential polarized imaging (DPI) of TTauri DoAr44. With a fairly axially symmetric ring in the submm radio continuum, DoAr44 is likely also a warped system. We constrain the warp geometry by comparing radiative transfer predictions with the DPI data in H band (Q_ϕ(H)) and with a re-processing of archival 336GHz ALMA observations. The observed DPI shadows have coincident radio counterparts, but the intensity drops are much deeper in Q_ϕ(H) (~88%), compared to the shallow drops at 336GHz (~24%). Radiative transfer predictions with an inner disk tilt of ~30+-5deg approximately account for the observations. ALMA long-baseline observations should allow the observation of the warped gas kinematics inside the cavity of DoAr44.

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Simon Casassus, Henning Avenhaus, Sebastian Perez, Victor Navarro, Miguel Carcamo, Sebastian Marino, Lucas Cieza, Sascha P. Quanz, Felipe Alarcon, Alice Zurlo, Axel Osses, Fernando R. Rannou, Pablo E. Romaan, Marcelo Barraza. 2018-04-06. An inner warp in the DoAr 44 T Tauri transition disk. https://doi.org/10.1093/mnras%2Fsty894

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