Line strengths and self-broadening coefficients of carbon dioxide isotopologues (13CO2 and 18O12C16O) near 2.04 µm for the in situ laser sensing of the Martian atmosphere

A diode laser spectrometer was used in the laboratory to study 13CO2 and 18O12C16O line intensities and self-broadening coefficients near 2.04 µm. The spectral region ranging from 4896 to 4903 cmµ1, which is suitable for in situ laser sensing of both isotopologues in the lower Martian atmosphere, was investigated using a distributed feedback GaInSb diode laser. Five lines of the (2 00 1)II¨(0 0 0) band of 13CO2 and seven lines of the (2 00 1)II¨(0 0 0) band of 18O12C16O were carefully revisited. The measured intensities and self-broadening coefficients were thoroughly compared with relevant molecular databases.