Submillimeter arcsecond-resolution mapping of the highly collimated protostellar jet HH 211
Por:
Lee C.-F., Ho P.T.P., Palau A., Hirano N., Bourke T.L., Shang H., Zhang Q.
Publicada:
1 ene 2007
Resumen:
We have mapped the protostellar jet HH 211 in 342 GHz continuum, SiO(J = 8-7), and CO (J = 3-2) emission at ? 1? resolution with the Submillimeter Array. Thermal dust emission is seen in continuum at the center of the jet, tracing an envelope and a possible optically thick compact disk (with a size <130 AU) around the protostar. A knotty jet is seen in CO and SiO as in H2, but extending closer to the protostar. It consists of a chain of knots on each side of the protostar, with an interknot spacing of ?2?-3? or 600-900 AU and the innermost pair of knots at only ?1.7? or 535 AU from the protostar. These knots likely trace unresolved internal (bow) shocks (i.e., working surfaces) in the jet, with a velocity range up to ?25 km s-1. The two-sided mass-loss rate of the jet is estimated to be ?(0.7-2.8) × 10-6 M ? yr-1. The jet is episodic, precessing, and bending. A velocity gradient is seen consistently across two bright SiO knots(BK3 and RK2) perpendicular to the jet axis, with ?1.5 ± 0.8 km s-1 at?30 ±15 AU, suggesting the presence of jet rotation. The launching radius of the jet, derived from the potential jet rotation, is ?0.15-0.06 AU in the inner disk. © 2007. 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
Harvard-Smithsonian Center for Astrophysics, Submillimeter Array, 645 North A'ohoku, Hilo, HI 96720, United States
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
Palau A.:
Laboratorio de Astrofísica Espacial y Física Fundamental, INTA, Apartado 50727, E-28080 Madrid, Spain
Hirano N.:
Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan
Bourke T.L.:
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, United States
Shang H.:
Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan
Zhang Q.:
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, United States
All Open Access; Green
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