ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions – XXI. A large-sample observational study of ethanol and dimethyl ether in hot cores
Year: 2025
Type: article
Abstract: ABSTRACT Hot cores, as a stage of massive star formation, exhibit abundant line emissions of complex organic molecules (COMs). We present a deep line survey of two isomers of C$_2$H$_6$O: ethanol (C$_2$H$_5$OH; EA), and dimethyl ether (CH$_3$OCH$_3$; DE) as well as their possible precursor CH$_3$OH towards 60 hot cores by using the Atacama Large Millimeter/submillimeter Array (ALMA) 3 mm line observations. EA is detected in 40 hot cores and DE is detected in 59 hot cores. Of these, EA and DE are simultaneously detected in 39 hot cores. We calculate rotation temperatures and column densities of EA and DE by using the eXtended CASA Line Analysis Software Suite (xclass) software. The average rotation temperature of EA is higher than that of DE, whereas the average column density of EA is lower than that of DE. Combined with previous studies of hot cores and hot corinos, we find strong column density correlations among EA and DE ($\rho$ = 0.92), EA and CH$_3$OH ($\rho$ = 0.82), as well as DE and CH$_3$OH ($\rho$ = 0.80). The column density ratios of EA/DE versus the column densities of CH$_3$OH remain nearly constant with values within ~1 order of magnitude. These strong correlations and the stable ratios, suggest that EA, DE, and CH$_3$OH could be chemically linked, with CH$_3$OH potentially serving as a precursor for EA and DE. Compared with chemical models, the three different warm-up time-scale models result in the systematic overproduction of EA and the systematic underproduction of DE. Therefore, our large sample observations can provide crucial constraints on chemical models.
Authors: Zhiping Kou, Xiaohu Li, Sheng-Li Qin, Tie Liu, E Mannfors, Xindi Tang, Prasanta Gorai, Guido Garay, Swagat R Das, Pablo García, Leonardo Bronfman, M Juvela, Li Chen, Xunchuan Liu, Patricio Sanhueza, Yaping Peng, Long-Fei Chen, Jiahang Zou, Dongting Yang, L Viktor Tóth, Lokesh Dewangan, Hong-Li Liu, James O Chibueze, Ziyang Li
Institutions: Yunnan University, Chinese Academy of Sciences, Xinjiang Astronomical Observatory, University of Chinese Academy of Sciences, Shanghai Astronomical Observatory, University of Helsinki, University of Oslo, National Astronomical Observatories, University of Chile, Universidad Católica del Norte, Guizhou Normal University, National Institutes of Natural Sciences, The Graduate University for Advanced Studies, SOKENDAI, National Astronomical Observatory of Japan, Institute of Science Tokyo, Kunming University of Science and Technology, Eötvös Loránd University, University of Debrecen, Physical Research Laboratory, University of Nigeria, University of South Africa, North-West University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,046
Funders: National Science Foundation, National Natural Science Foundation of China, Chinese Academy of Sciences, Alberta Livestock and Meat Agency, Ministry of Science and Technology, Korea Astronomy and Space Science Institute, European Southern Observatory, National Research Council Canada, National Institutes of Natural Sciences, National Key Research and Development Program of China
OpenAlex ID: W4408317693