TY - JOUR
T1 - Submillimeter emission from the hot molecular jet HH 211
AU - Palau, A.
AU - Ho, P. T.P.
AU - Zhang, Q.
AU - Estalella, R.
AU - Hirano, N.
AU - Shang, H.
AU - Lee, C. F.
AU - Bourke, T. L.
AU - Beuther, H.
AU - Kuan, Y. J.
N1 - Funding Information:
We appreciate the collaboration of the SMA staff in the observation and reduction process, specially from Chunhua Qi and Mark Gurwell. We wish to thank Mark McCaughrean and Jenniffer Wiseman for kindly providing the H2 and NH3images, respectively. A. P. is grateful to J. M. Girart for useful discussions. A. P. and R. E. are supported by MEC grant AYA2005-08523 and FEDER funds. H. B. acknowledges financial support from the Emmy-Noether-Program of the Dutsche Forschungsgemeinschaft (DFG, grant BE2578).
Funding Information:
1 Departament d’Astronomia i Meteorologia, Universitat de Barcelona, Av. Diagonal 647, E-08028 Barcelona, Spain. 2Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138. 3 Academia Sinica, Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei, 106, Taiwan. 4Max-Planck-Institut for Astronomy, Koenigstuhl 17, 69117 Heidelberg, Germany. 5Departament of Earth Science, National Taiwan Normal University, 88 Sec. 4, Ting-Chou Road, Taipei, 116, Taiwan. 6The Submillimeter Array is a joint project between the Smithsonian Astrophysical Observatory and the Academia Sinica Institute of Astronomy and Astrophysics, and is funded by the Smithsonian Institution and the Academia Sinica.
PY - 2006/1/10
Y1 - 2006/1/10
N2 - We observed the HH 211 jet in the submillimeter continuum and the CO (3-2) and SiO (8-7) transitions with the Submillimeter Array. The continuum source detected at the center of the outflow shows an elongated morphology, perpendicular to the direction of the outflow axis. The high-velocity emission of both molecules shows a knotty and highly collimated structure. The SiO (8-7) emission at the base of the outflow, close to the driving source, spans a wide range of velocities, from -20 up to 40 km s-1. This suggests that a wide-angle wind may be the driving mechanism of the HH 211 outflow. For distances ≥5″ (∼1500 AU) from the driving source, emission from both transitions follows a Hubble-law behavior, with SiO (8-7) reaching higher velocities than CO (3-2) and being located upstream of the CO (3-2) knots. This indicates that the SiO (8-7) emission is likely tracing entrained gas very close to the primary jet, while the CO (3-2) is tracing less dense entrained gas. From the SiO (5-4) data of Hirano et al., we find that the SiO (8-7)/SiO (5-4) brightness temperature ratio along the jet decreases for knots far from the driving source. This is consistent with the density decreasing along the jet, from (3-10) × 106 cm-3 at 500 AU to (0.8-4) × 106 cm-3 at 5000 AU from the driving source.
AB - We observed the HH 211 jet in the submillimeter continuum and the CO (3-2) and SiO (8-7) transitions with the Submillimeter Array. The continuum source detected at the center of the outflow shows an elongated morphology, perpendicular to the direction of the outflow axis. The high-velocity emission of both molecules shows a knotty and highly collimated structure. The SiO (8-7) emission at the base of the outflow, close to the driving source, spans a wide range of velocities, from -20 up to 40 km s-1. This suggests that a wide-angle wind may be the driving mechanism of the HH 211 outflow. For distances ≥5″ (∼1500 AU) from the driving source, emission from both transitions follows a Hubble-law behavior, with SiO (8-7) reaching higher velocities than CO (3-2) and being located upstream of the CO (3-2) knots. This indicates that the SiO (8-7) emission is likely tracing entrained gas very close to the primary jet, while the CO (3-2) is tracing less dense entrained gas. From the SiO (5-4) data of Hirano et al., we find that the SiO (8-7)/SiO (5-4) brightness temperature ratio along the jet decreases for knots far from the driving source. This is consistent with the density decreasing along the jet, from (3-10) × 106 cm-3 at 500 AU to (0.8-4) × 106 cm-3 at 5000 AU from the driving source.
KW - ISM: individual (HH 211)
KW - ISM: jets and outflows
KW - Stars: formation
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U2 - 10.1086/500242
DO - 10.1086/500242
M3 - Article
AN - SCOPUS:32044445988
SN - 0004-637X
VL - 636
SP - L137-L140
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 2 II
ER -