2003/11/04 by Fiona McGroarty, F. McGroarty, T. P. Ray +2 · 3 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:20034202
published as Astron.Astrophys. 415 (2004) 189-201 · 26 pages, 17 of which contain only images of poor resolution. Accepted by A&A. Full resolution draft available at http://www.dias.ie/dias/cosmic/astrophysics/general/Staff/homepages/fmcg/publ ications.html/McGroarty.ps.gz
arxiv created 2003/11/04 · openalex publication_date 2004/02/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
While there are many parsec–scale Herbig-Haro (HH) outflows known to be driven by low–mass young stars, few are associated with their intermediate mass counterparts. Here we present the discovery of five such bipolar outflows. Of these, LkHα 198, 1548C27 IRS 1, LkHα 233 and LkHα 234 were previously known to possess small-scale HH flows, while no such activity was observed before near IRAS 19395+2313. The largest of the newly discovered outflows are seen in the vicinity of LkHα 234 and 1548C27 IRS 1, and stretch (in projection) 8 pc and 7.5 pc respectively. LkHα 233 which was previously known to power a spectroscopically detected small-scale (≤10´´) jet is now seen to drive a 3 pc outflow and LkHα 198 is shown here to power a 2 pc outflow. Two HH objects in the vicinity of IRAS 19395+2313 lead us to suggest that it may also be responsible for a 5 pc outflow. In total, 27 new HH objects/complexes were discovered. Examination of these parsec–scale outflows show that they have similar lengths, morphologies, and dynamical timescales as those from low–mass sources. Many appear to have blown out of the parent cloud, suggesting that their total lengths are much greater than optically observed. The degree of collimation of these outflows is similar to those from low–mass sources suggesting that the transition to more poorly–collimated outflows must occur at higher masses than the sources observed here.