节点文献
Low temperature laser absorption spectra of methane in the near-infrared at 1.65 μm for lower state energy determination
【摘要】 Direct absorption spectra of the 2ν 3 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 CH 4 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.
【Abstract】 Direct absorption spectra of the 2ν 3 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 CH 4 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 spec-;
- 【文献出处】 Chinese Physics B ,中国物理B , 编辑部邮箱 ,2012年01期
- 【分类号】O433.51
- 【下载频次】49