The first exploration of the correlations between WISE 12 μm and CO emission in early-type galaxies

作     者：Gao, Yang Wang, Enci Tan, Qing-Hua Davis, Timothy A. Liang, Fu-Heng Jiang, Xue-Jian Gai, Ning Jiao, Qian Shi, DongDong Feng, Shuai Tang, Yanke Li, Shijie Wang, Yi-Fan 

作者机构：College of Physics and Electronic Information Dezhou University Dezhou253023 China International Centre of Supernovae Yunnan Key Laboratory Kunming650216 China CAS Key Laboratory for Research in Galaxies and Cosmology Department of Astronomy University of Science and Technology of China Hefei230026 China Purple Mountain Observatory Chinese Academy of Sciences 10 Yuanhua Road Nanjing210023 China Cardiff Hub for Astrophysics Research & Technology School of Physics & Astronomy Cardiff University Queens Buildings CardiffCF24 3AA United Kingdom  Karl-Schwarzschild-Straße 2 Garching85748 Germany Sub-department of Astrophysics Department of Physics University of Oxford Denys Wilkinson Building Keble Road OxfordOX1 3RH United Kingdom Research Center for Astronomical Computing Zhejiang Laboratory Hangzhou311121 China School of Electrical and Electronic Engineering Wuhan Polytechnic University Wuhan430023 China Center for Fundamental Physics School of Mechanics and Optoelectric Physics Anhui University of Science and Technology Anhui Huainan232001 China College of Physics Hebei Normal University 20 South Erhuan Road Shijiazhuang050024 China Guoshoujing Institute of Astronomy Hebei Normal University 20 South Erhuan Road Shijiazhuang050024 China Hebei Key Laboratory of Photophysics Research and Application Shijiazhuang050024 China 

出 版 物：《arXiv》 (arXiv)

年 卷 期：2024年

核心收录：

主　　题：Luminance 

摘      要：We present the analysis of a comprehensive sample of 352 early-type galaxies using public data, to investigate the correlations between CO luminosities and mid-infrared luminosities observed by Wide-field Infrared Survey Explorer (WISE). We find strong correlations between both CO (1-0) and CO (2-1) luminosities and 12 μm luminosity, boasting a correlation coefficient greater than 0.9 and an intrinsic scatter smaller than 0.1 dex. The consistent slopes observed for the relationships of CO (1-0) and CO (2-1) suggest that the line ratio R21 lacks correlation with mid-infrared emission in early-type galaxies, which is significantly different from star-forming galaxies. Moreover, the slopes of LCO(1−0)–L12μm and LCO(2−1)–L12μm relations in early-type galaxies are steeper than those observed in star-forming galaxies. Given the absence of correlation with color, morphology or sSFR, the correlation between deviations and the molecular gas mass surface density could be eliminated by correcting the possible 12 μm emission from old stars or adopting a systematically different αCO. The latter, on average, is equivalent to adding an constant CO brightness density, specifically 2.8−+00.86 [K km s−1] and 4.4−+21.24 [K km s−1] for CO (1-0) and (2-1) respectively. These explorations will serve as useful tools for estimating the molecular gas content in gas-poor galaxies and understanding associated quenching processes. © 2024, CC BY.