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

Abstract A diode laser spectrometer was used in the laboratory to study 13 CO 2 and 18 O 12 C 16 O line intensities and self-broadening coefficients near 2.04 μm. The spectral region ranging from 4896 to 4903 cm − 1 , 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 0 0  1) II ←(0 0 0) band of 13 CO 2 and seven lines of the (2 0 0  1) II ←(0 0 0) band of 18 O 12 C 16 O were carefully revisited. The measured intensities and self-broadening coefficients were thoroughly compared with relevant molecular databases.