Low temperature laser absorption spectra of methane in the near-infrared at 1.65 μm for lower state energy determination  

作　　者：Gao Wei Chen Wei-Dong Zhang Wei-Jun Yuan Yi-Qian Gao Xiao-Ming 高伟;陈卫东;张为俊;袁怿谦;高晓明(Key Laboratory of Atmospheric Composition and Optical Radiation,Chinese Academy of Sciences,Hefei 230031,China;Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei 230031,China;Laboratoire de Physicochimie de l'Atmosphère,Universitédu Littoral Côte d'Opale,189A,Av.Maurice Schumann,59140 Dunkerque,France)

机构地区：[1]Key Laboratory of Atmospheric Composition and Optical Radiation,Chinese Academy of Sciences,Hefei 230031,China [2]Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei 230031,China [3]Laboratoire de Physicochimie de l'Atmosphère,Universitédu Littoral Côte d'Opale,189A,Av.Maurice Schumann,59140 Dunkerque,France

出　　处：《Chinese Physics B》2012年第1期260-267,共8页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.41175036)

摘　　要：Direct absorption spectra of the 2v3 band of methane （CH4） from 6038 to 6050 cm 1 were studied at different low temperatures using a newly developed cryogenic cell in combination with a distributed feedback （DFB） diode laser. The cryogenic cell can operate at any stabilized temperature ranging from room temperature down to 100 K with temperature fluctuation less than =t=1 K within 1 hour. In the present work, the CH4 spectra in the range of 6038-6050 cm-1 were recorded at 296, 266, 248, 223, 198, and 176 K. The lower state energy Ett and the rotational assignment of the angular momentum J were determined by a ＂2-low-temperature spectra method＂ using the spectra recorded at 198 and 176 K. The results were compared with the data from the GOSAT and the recently reported results from Campargue and co-workers using two spectra measured at room temperature and 81 K. We demonstrated that the use of a 2-low-temperature spectra method permits one to complete the Ett and J values missed in the previous studies.Direct absorption spectra of the 2v3 band of methane （CH4） from 6038 to 6050 cm 1 were studied at different low temperatures using a newly developed cryogenic cell in combination with a distributed feedback （DFB） diode laser. The cryogenic cell can operate at any stabilized temperature ranging from room temperature down to 100 K with temperature fluctuation less than =t=1 K within 1 hour. In the present work, the CH4 spectra in the range of 6038-6050 cm-1 were recorded at 296, 266, 248, 223, 198, and 176 K. The lower state energy Ett and the rotational assignment of the angular momentum J were determined by a ＂2-low-temperature spectra method＂ using the spectra recorded at 198 and 176 K. The results were compared with the data from the GOSAT and the recently reported results from Campargue and co-workers using two spectra measured at room temperature and 81 K. We demonstrated that the use of a 2-low-temperature spectra method permits one to complete the Ett and J values missed in the previous studies.

关 键 词：METHANE laser absorption spectroscopy cryogenic cell low temperature absorption spec-trum 

分 类 号：O433.51[机械工程—光学工程]