2004/07/16 by Naomi Hirano, Hiroko Shinnaga, Dinh-V-Trung +9 · 2 citations
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Star Formation Studies #Gamma-ray bursts and supernovae #astro-ph
paper · pdf · doi:10.1086/424382
published as Astrophys.J. 616 (2004) L43-L46 · 11 pages, 4 figures, accepted by the ApJL
arxiv created 2004/07/16 · openalex publication_date 2004/10/28 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
Using the partially completed Submillimeter Array with five antennas, we have observed the CO J = 2-1 and 3-2 emission from the envelope surrounding the carbon star V Hya. The high angular resolution (2''-4'') maps show that V Hya is powering a bipolar molecular jet with an extreme velocity of 70-185 km s -1 . The axis of this high-velocity jet is perpendicular to the major axis of the flattened disklike envelope, which is expanding with a velocity of ~16 km s -1 . There is a third kinematic component, a medium-velocity wind with a deprojected velocity of 40-120 km s -1 moving along the disk plane. Both the high-velocity jet and the medium-velocity wind have a dynamical timescale of a few hundred years. The flattened structure and the collimated jet observed in V Hya suggest that the formation of asymmetrical structure proceeds while the central star is still in the asymptotic giant branch phase.