High-sensitivity millimeter imaging of molecular outflows in nine nearby high-mass star-forming regions

• Published in: arXiv.org
• Main Authors: De-Jian, Liu, Xu, Ye, Ying-Jie, Li, Zheng, Sheng, Deng-Rong, Lu, Chao-Jie, Hao, Ze-Hao Lin, Shuai-Bo Bian, Li-Ming, Liu
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 06.12.2020
• Subjects: Bolometers; Carbon monoxide; Massive stars; Mountains; Observatories; Outflow; Physics - Astrophysics of Galaxies; Sensitivity; Star formation
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2012.03226

We present a study of molecular outflows using six molecular lines (including 12CO/13CO/C18O/HCO+(J = 1-0) and SiO/CS(J = 2-1)) toward nine nearby high-mass star-forming regions with accurate known distances. This work is based on the high-sensitivity observations obtained with the 14-m millimeter telescope of Purple Mountain Observatory Delingha (PMODLH) observatory. The detection rate of outflows (including 12CO, 13CO, HCO+, and CS) is 100\%. However, the emission of SiO was not detected for all sources. The full line widths (\(\Delta V\)) at 3\(\sigma\) above the baseline of these molecular lines have the relationship \(\Delta V_{\rm ^{12}CO} > \Delta V_{\rm HCO^{+}} > \Delta V_{\rm CS} \approx \Delta V_{\rm ^{13}CO} > \Delta V_{\rm ^{18}CO}\). 12CO and HCO+ can be used to trace relatively high-velocity outflows, while 13CO and CS can be employed to trace relatively low-velocity outflows. The dynamical timescales of the 13CO and CS outflows are longer than those of the 12CO and HCO+ outflows. The mechanical luminosities, masses, mass-loss rates and forces of all outflows (including 12CO, 13CO, HCO+, and CS) are correlated with the bolometric luminosities of their central IRAS sources.