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arXiv · 2011.06345

A triple star in disarray -- Multi-epoch observations of T Tauri with VLT-SPHERE and LBT-LUCI

M. Kasper·K. K. R. Santhakumari·T. M. Herbst·R. van Boekel·F. Menard·R. Gratton·R. G. van Holstein·M. Langlois·C. Ginski·A. Boccaletti·J. de Boer·P. Delorme·S. Desidera·C. Dominik·J. Hagelberg·T. Henning·R. Koehler·D. Mesa·S. Messina·A. Pavlov·C. Petit·E. Rickman·A. Roux·F. Rigal·A. Vigan·Z. Wahhaj·A. Zurlo
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Abstract

T Tauri remains an enigmatic triple star for which neither the evolutionary state of the stars themselves, nor the geometry of the complex outflow system is completely understood. Eight-meter class telescopes equipped with state-of-the-art adaptive optics provide the spatial resolution necessary to trace tangential motion of features over a timescale of a few years, and they help to associate them with the different outflows. We used J-, H-, and K-band high-contrast coronagraphic imaging with VLT-SPHERE recorded between 2016 and 2018 to map reflection nebulosities and obtain high precision near-infrared (NIR) photometry of the triple star. We also present molecular hydrogen emission maps of the 1-0 S(1) line at 2.122 micron obtained with LBT-LUCI during its commissioning period at the end of 2016. The data reveal a number of new features in the system, some of which are seen in reflected light and some are seen in H2 emission; furthermore, they can all be associated with the main outflows. The tangential motion of the features provides compelling evidence that T Tauri Sb drives the southeast-northwest outflow. T Tauri Sb has recently faded probably because of increased extinction as it passes through the southern circumbinary disk. While T Tauri Sb is approaching periastron, T Tauri Sa instead has brightened and is detected in all our J-band imagery for the first time.

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M. Kasper, K. K. R. Santhakumari, T. M. Herbst, R. van Boekel, F. Menard, R. Gratton, R. G. van Holstein, M. Langlois, C. Ginski, A. Boccaletti, J. de Boer, P. Delorme, S. Desidera, C. Dominik, J. Hagelberg, T. Henning, R. Koehler, D. Mesa, S. Messina, A. Pavlov, C. Petit, E. Rickman, A. Roux, F. Rigal, A. Vigan, Z. Wahhaj, A. Zurlo. 2020-11-12. A triple star in disarray -- Multi-epoch observations of T Tauri with VLT-SPHERE and LBT-LUCI. https://doi.org/10.1051/0004-6361/202039186

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