Evidence of a SiO collimated outflow from a massive YSO in IRAS 17233–3606

¹ Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
e-mail: sleurini@mpifr.de
² INAF – Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy
³ LERMA, UMR 8112 du CNRS, Observatoire de Paris, École Normale Supérieure, 24 rue Lhomond, 75231 Paris Cedex 05, France
⁴ Centro de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, 58090 Morelia, Mexico
⁵ ESO, Karl-Schwarzschild Strasse 2, 85748 Garching-bei-München, Germany
⁶ Caltech, 1200 E. California Blvd, Pasadena, CA 91125, USA

Received: 26 September 2011
Accepted: 3 April 2013

Abstract

Studies of molecular outflows in high-mass young stellar objects reveal important information about the formation process of massive stars. We therefore selected the close-by IRAS 17233–3606 massive star-forming region to perform SiO observations with the SMA interferometer in the (5−4) line and with the APEX single-dish telescope in the (5−4) and (8–7) transitions. In this paper, we present a study of one of the outflows in the region, OF1, which shows several properties similar to jets driven by low-mass protostars, such as HH211 and HH212. It is compact and collimated, and associated with extremely high velocity CO emission, and SiO emission at high velocities. We used a state-of-the-art shock model to constrain the pre-shock density and shock velocity of OF1. The model also allowed us to self-consistently estimate the mass of the OF1 outflow. The shock parameters inferred by the SiO modelling are comparable with those found for low-mass protostars, only with higher pre-shock density values, yielding an outflow mass in agreement with those obtained for molecular outflows driven by early B-type young stellar objects. Our study shows that it is possible to model the SiO emission in high-mass star-forming regions in the same way as for shocks from low-mass young stellar objects.