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arXiv · 2006.15850

ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): I. Detection of New Hot Corinos with ACA

Shih-Ying Hsu·Sheng-Yuan Liu·Tie Liu·Dipen Sahu·Naomi Hirano·Chin-Fei Lee·Kenichi Tatematsu·Gwanjeong Kim·Mika Juvela·Patricio Sanhueza·Jinhua He·Doug Johnstone·Sheng-Li Qin·Leonardo J. Bronfman·Huei-Ru Chen·Somnath Dutta·David Eden·Kai-Syun Jhan·Kee-Tae Kim·Yi-Jehng Kuan·Woojin Kwon·Chang Won Lee·Jeong-Eun Lee·Anthony Moraghan·Mark Rawlings·Hsien Shang·Archana Soam·Mark Thompson·Alessio Traficante·Yuefang Wu·Yao-Lun Yang·Qizhou Zhang
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Abstract

We report the detection of four new hot corino sources, G211.47-19.27S, G208.68-19.20N1, G210.49-19.79W and G192.12-11.10 from a survey study of Planck Galactic Cold Clumps in the Orion Molecular Cloud Complex with the Atacama Compact Array (ACA). Three sources had been identified as low mass Class 0 protostars in the Herschel Orion Protostar Survey (HOPS). One source in the lambda Orionis region is firstly reported as a protostellar core. We have observed abundant complex organic molecules (COMs), primarily methanol but also other oxygen-bearing COMs (in G211.47-19.27S and G208.68-19.20N1) and the molecule of prebiotic interest NH2CHO (in G211.47-19.27S), signifying the presence of hot corinos. While our spatial resolution is not sufficient for resolving most of the molecular emission structure, the large linewidth and high rotational temperature of COMs suggest that they likely reside in the hotter and innermost region immediately surrounding the protostar. In G211.47-19.27S, the D/H ratio of methanol ([CH2DOH]/[CH3OH]) and the 12C/13C ratio of methanol ([CH3OH]/[13CH3OH]) are comparable to those of other hot corinos. Hydrocarbons and long carbon-chain molecules such as c-C3H2 and HCCCN are also detected in the four sources, likely tracing the outer and cooler molecular envelopes.

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Shih-Ying Hsu, Sheng-Yuan Liu, Tie Liu, Dipen Sahu, Naomi Hirano, Chin-Fei Lee, Kenichi Tatematsu, Gwanjeong Kim, Mika Juvela, Patricio Sanhueza, Jinhua He, Doug Johnstone, Sheng-Li Qin, Leonardo J. Bronfman, Huei-Ru Chen, Somnath Dutta, David Eden, Kai-Syun Jhan, Kee-Tae Kim, Yi-Jehng Kuan, Woojin Kwon, Chang Won Lee, Jeong-Eun Lee, Anthony Moraghan, Mark Rawlings, Hsien Shang, Archana Soam, Mark Thompson, Alessio Traficante, Yuefang Wu, Yao-Lun Yang, Qizhou Zhang. 2020-06-29. ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): I. Detection of New Hot Corinos with ACA. https://doi.org/10.3847/1538-4357/ab9f3a

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