Disk Evolution Study Through Imaging of Nearby Young Stars (DESTINYS): Characterization of the young star T CrA and its circumstellar environment^★,★★

¹ INAF/Osservatorio Astronomico di Padova, Vicolo dell'osservatorio 5, 35122 Padova. Italy
e-mail: elisabetta.rigliaco@inaf.it
² Dipartimento di Fisica, Università Degli Studi di Milano, Via Celoria, 16, Milano 20133, Italy
³ Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands
⁴ Leiden Observatory, Leiden University, PO Box 9513, 2300 RA, Leiden, The Netherlands
⁵ Unidad Mixta Internacional Franco-Chilena de Astronomia, CNRS/INSU UMI 3386, Departamento de Astronomia, Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago, Chile
⁶ Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
⁷ University Observatory, Faculty of Physics, Ludwig-Maximilians-Universität München, Scheinerstr. 1, 81679 Munich, Germany
⁸ Exzellenzcluster ORIGINS, Boltzmannstr. 2, 85748 Garching, Germany
⁹ INAF, Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy
¹⁰ Department of Astronomy, University of Florida, Gainesville, FL 32611, USA
¹¹ CRAL, UMR 5574, CNRS, Université Lyon 1, 9 avenue Charles André, 69561 Saint-Genis-Laval Cedex, France
¹² Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA
¹³ European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, Germany
¹⁴ Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, UK
¹⁵ Nucleo de Astronomia, Facultad de Ingenieria y Ciencias, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile
¹⁶ Escuela de Ingenieria Industrial, Facultad de Ingenieria y Ciencias, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile
¹⁷ Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France

Received: 12 October 2022
Accepted: 22 December 2022

Abstract

Context. In recent years, a new hot topic has emerged in the star and planet formation field, namely, the interaction between the circumstellar disk and its birth cloud. The birth environments of young stars leave strong imprints on the star itself and their surroundings. In this context, we present a detailed analysis of the rich circumstellar environment around the young Herbig Ae/Be star T CrA.

Aims. Our aim is to understand the nature of the stellar system and the extended circumstellar structures, as seen in scattered light images.

Methods. We conducted our analysis on the basis of a set of combined archival data and new adaptive optics images at a high contrast and high resolution.

Results. The scattered light images reveal the presence of a complex environment around T CrA, composed of a bright, forward-scattering rim of the disk's surface that is seen at very high inclinations, along with a dark lane of the disk midplane, bipolar outflows, and streamer features that are likely tracing infalling material from the surrounding birth cloud onto the disk. The analysis of the light curve suggests that the star is a binary with a period of 29.6 yr, confirming previous assertions based on spectro-astrometry. The comparison of the scattered light images with the ALMA continuum and ¹²CO (2–1) line emission shows that the disk is in Keplerian rotation and the northern side of the outflowing material is receding, while the southern side is approaching the observer. The overall system lies on different geometrical planes. The orbit of the binary star is perpendicular to the outflows and is seen edge on. The disk is itself seen edge-on, with a position angle of ~7°. The direction of the outflows seen in scattered light is in agreement with the direction of the more distant molecular hydrogen emission-line objects (MHOs) associated with the star. Modeling of the spectral energy distribution using a radiative transfer scheme is in good agreement with the proposed configuration, as well as the hydrodynamical simulation performed using a smoothed particle hydrodynamics code.

Conclusions. We find evidence of streamers of accreting material around T CrA. These streamers connect the filament, along which T CrA is forming along with the outer parts of the disk, suggesting that the strong misalignment between the inner and outer disk is due to a change in the direction of the angular momentum of the material accreting on the disk during the late phase of star formation. This impacts the accretion taking place in the components of the binary, favoring the growth of the primary with respect the secondary, in contrast to the case of aligned disks.