Symmetry properties and widths of the filamentary structures in the Orion A giant molecular cloud  

作　　者：Yu-Qing Zheng Hong-Chi Wang Yue-Hui Ma Chong Li 

机构地区：[1]Purple Mountain Observatory and Key Laboratory of Radio Astronomy,Chinese Academy of Sciences,Nanjing 210033,China [2]School of Astronomy and Space Science,University of Science and Technology of China,Hefei 230026,China [3]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Research in Astronomy and Astrophysics》2021年第8期23-45,共23页天文和天体物理学研究（英文版）

基　　金：supported by National Key R&D Program of China (Grant 2017YFA0402701);Key Research Program of Frontier Sciences of CAS (Grant QYZDJ-SSW-SLH047);support by the National Natural Science Foundation of China (NSFC,Grant No.1973091);supports by the NSFC (Nos.11503086 and 11503087)。

摘　　要：We identify 225 filaments from an H2 column density map constructed using simultaneous 12CO,13CO and C18O(J=1-0) observations carried out as a part of the Milky Way Imaging Scroll Painting(MWISP) project.We select 46 long filaments with lengths above 1.2 pc to analyze the filament column density profiles.We divide the selected filaments into 397 segments and calculate the column density profiles for each segment.The symmetries of the profiles are investigated.The proportion of intrinsically asymmetrical segments is 65.3%,and that of intrinsically symmetrical ones is 21.4%.The typical full width at half maximum(FWHM) of the intrinsically symmetrical filament segments is - 0.67 pc with the Plummer-like fitting,and - 0.50 pc with the Gaussian fitting,respectively.The median FWHMs derived from the second-moment method for intrinsically symmetrical and asymmetrical profiles are - 0.44 and 0.46 pc,respectively.Close association exists between the filamentary structures and the YSOs in the region.

关 键 词：ISM:clouds ISM:individual objects(Orion A) ISM:structure stars:formation 

分 类 号：P155.2[天文地球—天文学]