中国物理B ›› 2012, Vol. 21 ›› Issue (1): 14211-014211.doi: 10.1088/1674-1056/21/1/014211

• • 上一篇    下一篇

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

高伟1, 张为俊1, 袁怿谦1, 高晓明1, 陈卫东2   

  1. (1)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; (2)Laboratoire de Physicochimie de l'Atmosphère, Université du Littoral Côte d'Opale, 189A, Av. Maurice Schumann, 59140 Dunkerque, France
  • 收稿日期:2011-07-11 修回日期:2011-09-06 出版日期:2012-01-15 发布日期:2012-01-20
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 41175036).

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

Gao Wei(高伟)a)b), Chen Wei-Dong(陈卫东)c), Zhang Wei-Jun(张为俊)a)b), Yuan Yi-Qian(袁怿谦)a)b), and Gao Xiao-Ming(高晓明)a)b)†   

  1. a Key Laboratory of Atmospheric Composition and Optical Radiation, Chinese Academy of Sciences, Hefei 230031, Chinab Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China; b Laboratoire de Physicochimie de l'Atmosphère, Université du Littoral Côte d'Opale, 189A, Av. Maurice Schumann, 59140 Dunkerque, France
  • Received:2011-07-11 Revised:2011-09-06 Online:2012-01-15 Published:2012-01-20
  • Supported by:
    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 ±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 E″ 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 E″ and J values missed in the previous studies.

关键词: methane, laser absorption spectroscopy, cryogenic cell, low temperature absorption spectrum

Abstract: 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 ±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 E″ 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 E″ and J values missed in the previous studies.

Key words: methane, laser absorption spectroscopy, cryogenic cell, low temperature absorption spectrum

中图分类号:  (Spectral absorption by atmospheric gases)

  • 42.68.Ca
25.20.Dc (Photon absorption and scattering) 78.20.Ci (Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity))