Volume 573, January 2015
|Number of page(s)||5|
|Published online||18 December 2014|
Observatorio Astronómico Nacional (IGN),
Alfonso XII 3,
2 Univ. Grenoble Alpes, IPAG, 38000 Grenoble, France
3 CNRS, IPAG, 38000 Grenoble, France
4 CESBIO (UMR 5126), Obs. de Midi-Pyrénées (CNES, CNRS, Univ. Paul Sabatier, IRD), 31401 Toulouse, France
5 INAF, Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy
6 Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
Received: 31 October 2014
Accepted: 25 November 2014
Context. L1157-mm powers a molecular outflow that is well-known for its shock-induced chemical activity in several hot-spots.
Aims. We have studied the molecular emission toward L1157-mm searching for a jet component responsible for these spots.
Methods. We used the IRAM 30 m telescope to observe the vicinity of L1157-mm in several lines of SiO.
Results. The SiO(5–4) and SiO(6–5) spectra toward L1157-mm present blue and red detached components about 45 km s-1 away from the ambient cloud. These extremely high-velocity (EHV) components are similar to those found in the L1448 and IRAS 04166+2706 outflows and probably arise from a molecular jet driven by L1157-mm. Observations of off-center positions indicate that the jet is unresolved in SiO(5–4) (< 11′′).
Conclusions. The EHV jet seen in SiO probably excites L1157-B1 and the other chemically active spots of the L1157 outflow.
Key words: stars: formation / ISM: abundances / ISM: jets and outflows / ISM: molecules
Based on IRAM 30 m Telescope observations. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).
Tables 1 and 2 are available in electronic form at http://www.aanda.org
© ESO, 2014
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.