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arXiv · 2306.07839

ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): A forming quadruple system with continuum `ribbons' and intricate outflows

Qiu-yi Luo·Tie Liu·Aaron T. Lee·Stella S. R. Offner·James di Francesco·Doug Johnstone·Mika Juvela·Paul F. Goldsmith·Sheng-Li Qin·Xiaofeng Mai·Xun-chuan Liu·Patricio Sanhueza·Feng-Wei Xu·Ken'ichi Tatematsu·Somnath Dutta·Huei-Ru Vivien Chen·Shanghuo Li·Aiyuan Yang·Sheng-Yuan Liu·Chin-Fei Lee·Naomi Hirano·Chang Won Lee·Dipen Sahu·Hsien Shang·Shih-Ying Hsu·Leonardo Bronfman·Woojin Kwon·M. G. Rawlings·David Eden·Xing Lu·Qi-lao Gu·Zhiyuan Ren·D Ward-Thompson·Zhi-Qiang Shen
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Abstract

One of the most poorly understood aspects of low-mass star formation is how multiple-star systems are formed. Here we present the results of Atacama Large Millimeter/submillimeter Array (ALMA) Band-6 observations towards a forming quadruple protostellar system, G206.93-16.61E2, in the Orion B molecular cloud. ALMA 1.3 mm continuum emission reveals four compact objects, of which two are Class I young stellar objects (YSOs), and the other two are likely in prestellar phase. The 1.3 mm continuum emission also shows three asymmetric ribbon-like structures that are connected to the four objects, with lengths ranging from $\sim$500 au to $\sim$2200 au. By comparing our data with magneto-hydrodynamic (MHD) simulations, we suggest that these ribbons trace accretion flows and also function as gas bridges connecting the member protostars. Additionally, ALMA CO J=2-1 line emission reveals a complicated molecular outflow associated with G206.93-16.61E2 with arc-like structures suggestive of an outflow cavity viewed pole-on.

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Qiu-yi Luo, Tie Liu, Aaron T. Lee, Stella S. R. Offner, James di Francesco, Doug Johnstone, Mika Juvela, Paul F. Goldsmith, Sheng-Li Qin, Xiaofeng Mai, Xun-chuan Liu, Patricio Sanhueza, Feng-Wei Xu, Ken'ichi Tatematsu, Somnath Dutta, Huei-Ru Vivien Chen, Shanghuo Li, Aiyuan Yang, Sheng-Yuan Liu, Chin-Fei Lee, Naomi Hirano, Chang Won Lee, Dipen Sahu, Hsien Shang, Shih-Ying Hsu, Leonardo Bronfman, Woojin Kwon, M. G. Rawlings, David Eden, Xing Lu, Qi-lao Gu, Zhiyuan Ren, D Ward-Thompson, Zhi-Qiang Shen. 2023-06-13. ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): A forming quadruple system with continuum `ribbons' and intricate outflows. https://doi.org/10.3847/2041-8213%2Facdddf

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