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arXiv · 1709.10247

Widespread Presence of Glycolaldehyde and Ethylene Glycol Around Sagittarius B2

Juan Li·Zhiqiang Shen·Junzhi Wang·Xi Chen·Di Li·Yajun Wu·Jian Dong·Rongbing Zhao·Wei Gou·Jinqing Wang·Shanghuo Li·Bingru Wang·Xingwu Zheng
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Abstract

We report the detection of widespread CH$_2$OHCHO and HOCH$_2$CH$_2$OH emission in Galactic center giant molecular cloud Sagittarius B2 using the Shanghai Tianma 65m Radio Telescope. Our observations show for the first time that the spatial distribution of these two important prebiotic molecules extends over 15 arc-minutes, corresponding to a linear size of approximately 36 pc. These two molecules are not just distributed in or near the hot cores. The abundance of these two molecules seems to decrease from the cold outer region to the central region associated with star-formation activity. Results present here suggest that these two molecules are likely to form through a low temperature process. Recent theoretical and experimental studies demonstrated that prebiotic molecules can be efficiently formed in icy grain mantles through several pathways. However, these complex ice features cannot be directly observed, and most constraints on the ice compositions come from millimeter observations of desorbed ice chemistry products. These results, combined with laboratory studies, strongly support the existence of abundant prebiotic molecules in ices.

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Juan Li, Zhiqiang Shen, Junzhi Wang, Xi Chen, Di Li, Yajun Wu, Jian Dong, Rongbing Zhao, Wei Gou, Jinqing Wang, Shanghuo Li, Bingru Wang, Xingwu Zheng. 2017-09-29. Widespread Presence of Glycolaldehyde and Ethylene Glycol Around Sagittarius B2. https://doi.org/10.3847/1538-4357%2Faa9069

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