Yiqian Yuan

High resolution absorption spectroscopy of water vapor between 7600 cm-1 and 7615 cm-1

We measured the high resolution absorption spectroscopy of water vapor between 7599cm-1 and 7615cm-1 by narrow linewidth DFB diode laser and kilometers order long path White cell. We observed the minimum detectable absorption of the 10-26 cm/molecular line strength. The measured line parameters show excellent agreements with the values from HITRAN2000 database. The 7600.133 cm-1 line of water vapor listed in HITRAN2000 database was not observed we think the line is inexistent. Seven new weak lines unlisted in HITRAN2000 database were observed which may belong to the isotope H2180 molecular.

High sensitivity absorption spectroscopy of CH 4 around 1.31 μm

The absorption spectra of CH4 around 1.31 μm have been observed by wavelength modulation absorption spectroscopy technique employed with a tunable diode laser at different pressure. The overtone spectra of CH4 around 1.31 μm and the corresponding spectral parameters (i.e. positions intensities self-broadening coefficients) are presented. The intensity of the weakest line detected is 1.306x10-26 cm-1/(molecule-cm-2) at the pressure of 0.077 Torr with a corresponding absorption of l.174x10-7.