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arXiv · 2210.02767

CN 2-1 and CS 5-4 observations toward Arp 299 with the SMA

Junzhi Wang·Chunhua Qi·Shanghuo Li·Jingwen Wu
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Abstract

Dense gas is the key for understanding star formation in galaxies. We present high resolution ($\sim3''$) observations of CN 2-1 and CS 5-4 as dense gas tracers toward Arp 299, a mid stage major merger of galaxies, with the Submillimeter Array (SMA). The spatial distribution of CN 2-1 and CS 5-4 are generally consistent with each other, as well as HCN 1-0 in literature. However, different line ratios of CS 5-4 and CN 2-1 are found in A, B, and C regions, with highest value in B. Dense gas fraction decreases from IC 694 (A), to NGC 3690 (B) and the overlap starburst region (C and C$'$), which indicates that circum-nuclear upcoming starburst in A and B will be more efficient than that in the overlap region of Arp 299.

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Junzhi Wang, Chunhua Qi, Shanghuo Li, Jingwen Wu. 2022-10-06. CN 2-1 and CS 5-4 observations toward Arp 299 with the SMA. https://doi.org/10.3847/1538-4357/ac9122

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