Letter to the Editor

ALMA detects a radial disk wind in DG Tauri^⋆

¹ University of Vienna, Dept. of Astrophysics, Türkenschanzstr. 17, 1180 Vienna, Austria
e-mail: manuel.guedel@univie.ac.at
² Department of Astronomy, University of Geneva, Ch. d’Ecogia 16, 1290 Versoix, Switzerland
³ University of Hertfordshire, Hatfield, Hertfordshire, UK
⁴ University of Exeter, School of Physics and Astronomy, Stocker Road, Exeter EX4 4QL, UK
⁵ Kapteyn Astronomical Institute, University of Groningen, PO Box 800 9700 AV Groningen, The Netherlands
⁶ Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg, Germany
⁷ Center for Astrophysics and Space Astronomy, University of Colorado, 389 UCB, Boulder, CO 80309-0389, USA
⁸ Research Institute of Physics, Southern Federal University, Stachki Ave. 194, Rostov-on-Don, Russia

Received: 18 September 2018
Accepted: 20 October 2018

Abstract

Aims. We aim to use the high spatial resolution of the Atacama Large Millimeter/submillimeter Array (ALMA) to map the flow pattern of molecular gas near DG Tauri and its disk, a young stellar object driving a jet and a molecular outflow.

Methods. We use observations from ALMA in the J = 2 − 1 transition of ¹²CO, ¹³CO, and C¹⁸O to study the Keplerian disk of DG Tauri and outflows that may be related to the disk and the jet.

Results. We find a new wind component flowing radially at a steep angle (≈25° from the vertical) above the disk with a velocity of ≈3.1 km s⁻¹. It continues the trend of decreasing velocity for increasing distance from the jet axis (“onion-like velocity structure”).

Conclusions. The new component is located close to the protostellar disk surface and may be related to photoevaporative winds.