The reflection-symmetric wiggle of the young protostellar jet HH 211
Por:
Lee C.-F., Hasegawa T.I., Hirano N., Palau A., Shang H., Ho P.T.P., Zhang Q.
Publicada:
1 ene 2010
Resumen:
HH 211 is a highly collimated jet originating from a nearby young Class 0 protostar. Here is a follow-up study of the jet with our previous observations at unprecedented resolution up to 03 in SiO (J = 8-7), CO (J = 3-2), and SO (NJ = 89-78). SiO, CO, and SO can all be a good tracer of the HH 211 jet, tracing the internal shocks in the jet. Although the emissions of these molecules show roughly the same morphology of the jet, there are detailed differences. In particular, the CO emission traces the jet closer to the source than the SiO and SO emissions. In addition, in the better resolved internal shocks, both the CO and SO emission are seen slightly ahead of the SiO emission. The jet is clearly seen on both sides of the source with more than one cycle of wiggle. The wiggle is reflection-symmetric about the source and can be reasonably fitted by an orbiting source jet model. The best-fit parameters suggest that the source itself could be a very low mass protobinary with a total mass of 60 M Jup and a binary separation of 4.6AU. The abundances of SiO and SO in the gas phase are found to be highly enhanced in the jet as compared to the quiescent molecular clouds, even close to within 300AU from the source where the dynamical timescale is <10yr. The abundance enhancements of these molecules are closely related to the internal shocks. The detected SiO is either the consequence of the release of Si-bearing material from dust grains or of its formation via gas chemistry in the shocks. The SO, on the other hand, seems to form via gas chemistry in the shocks. © 2010. The American Astronomical Society. All rights reserved..
Filiaciones:
Lee C.-F.:
Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan
Hasegawa T.I.:
Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan
Hirano N.:
Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan
Palau A.:
Laboratorio de Astrofísica Estelar y Exoplanetas, Centro de Astrobiología (INTA-CSIC), LAEFF Campus, P.O. Box 78, E-28691 Villanueva de la Cãada (Madrid), Spain
Shang H.:
Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan
Ho P.T.P.:
Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, United States
Zhang Q.:
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, United States
All Open Access, Bronze
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