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Title: THE HIGH-VELOCITY MOLECULAR OUTFLOWS IN MASSIVE CLUSTER-FORMING REGION G10.6-0.4

Abstract

We report the arcsecond resolution Submillimeter Array observations of the {sup 12}CO (2-1) transition in the massive cluster-forming region G10.6-0.4. In these observations, the high-velocity {sup 12}CO emission is resolved into individual outflow systems, which have a typical size scale of a few arcseconds. These molecular outflows are energetic and are interacting with the ambient molecular gas. By inspecting the shock signatures traced by CH{sub 3}OH, SiO, and HCN emissions, we suggest that abundant star formation activities are distributed over the entire 0.5 pc scale dense molecular envelope. The star formation efficiency over one global free-fall timescale (of the 0.5 pc molecular envelope, {approx}10{sup 5} years) is about a few percent. The total energy feedback of these high-velocity outflows is higher than 10{sup 47} erg, which is comparable to the total kinetic energy in the rotational motion of the dense molecular envelope. From order-of-magnitude estimations, we suggest that the energy injected from the protostellar outflows is capable of balancing the turbulent energy dissipation. No high-velocity bipolar molecular outflow associated with the central OB cluster is directly detected, which can be due to the photoionization.

Authors:
; ;  [1]
  1. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
Publication Date:
OSTI Identifier:
21476640
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 725; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/725/2/2190
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; EMISSION; ENERGY LOSSES; HYDROCYANIC ACID; KINETIC ENERGY; METHANOL; PHOTOIONIZATION; SILICON OXIDES; STAR EVOLUTION; STARS; ALCOHOLS; CHALCOGENIDES; ENERGY; EVOLUTION; HYDROGEN COMPOUNDS; HYDROXY COMPOUNDS; INORGANIC ACIDS; INORGANIC COMPOUNDS; IONIZATION; LOSSES; ORGANIC COMPOUNDS; OXIDES; OXYGEN COMPOUNDS; SILICON COMPOUNDS

Citation Formats

Liu Hauyu Baobab, Ho, Paul T. P., and Zhang Qizhou, E-mail: hlu@cfa.havard.ed, E-mail: pho@asiaa.sinica.edu.t. THE HIGH-VELOCITY MOLECULAR OUTFLOWS IN MASSIVE CLUSTER-FORMING REGION G10.6-0.4. United States: N. p., 2010. Web. doi:10.1088/0004-637X/725/2/2190.
Liu Hauyu Baobab, Ho, Paul T. P., & Zhang Qizhou, E-mail: hlu@cfa.havard.ed, E-mail: pho@asiaa.sinica.edu.t. THE HIGH-VELOCITY MOLECULAR OUTFLOWS IN MASSIVE CLUSTER-FORMING REGION G10.6-0.4. United States. doi:10.1088/0004-637X/725/2/2190.
Liu Hauyu Baobab, Ho, Paul T. P., and Zhang Qizhou, E-mail: hlu@cfa.havard.ed, E-mail: pho@asiaa.sinica.edu.t. 2010. "THE HIGH-VELOCITY MOLECULAR OUTFLOWS IN MASSIVE CLUSTER-FORMING REGION G10.6-0.4". United States. doi:10.1088/0004-637X/725/2/2190.
@article{osti_21476640,
title = {THE HIGH-VELOCITY MOLECULAR OUTFLOWS IN MASSIVE CLUSTER-FORMING REGION G10.6-0.4},
author = {Liu Hauyu Baobab and Ho, Paul T. P. and Zhang Qizhou, E-mail: hlu@cfa.havard.ed, E-mail: pho@asiaa.sinica.edu.t},
abstractNote = {We report the arcsecond resolution Submillimeter Array observations of the {sup 12}CO (2-1) transition in the massive cluster-forming region G10.6-0.4. In these observations, the high-velocity {sup 12}CO emission is resolved into individual outflow systems, which have a typical size scale of a few arcseconds. These molecular outflows are energetic and are interacting with the ambient molecular gas. By inspecting the shock signatures traced by CH{sub 3}OH, SiO, and HCN emissions, we suggest that abundant star formation activities are distributed over the entire 0.5 pc scale dense molecular envelope. The star formation efficiency over one global free-fall timescale (of the 0.5 pc molecular envelope, {approx}10{sup 5} years) is about a few percent. The total energy feedback of these high-velocity outflows is higher than 10{sup 47} erg, which is comparable to the total kinetic energy in the rotational motion of the dense molecular envelope. From order-of-magnitude estimations, we suggest that the energy injected from the protostellar outflows is capable of balancing the turbulent energy dissipation. No high-velocity bipolar molecular outflow associated with the central OB cluster is directly detected, which can be due to the photoionization.},
doi = {10.1088/0004-637X/725/2/2190},
journal = {Astrophysical Journal},
number = 2,
volume = 725,
place = {United States},
year = 2010,
month =
}
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