Self-broadening coefficients and positions of acetylene around 1.533 μm studied by high-resolution diode laser absorption spectrometry

Abstract

The self-broadening coefficients of acetylene at room temperature have been measured for 10 lines in the P branch of the ν 1 + ν 3 ( ∑ u + ) − 0 ( ∑ g + ) bands of 12C 2H 2 and 13C 12CH 2 near 1.533 μm, using a high resolution tunable diode laser spectrometer developed for the Martian space mission PHOBOS-Grunt. The collisional widths are obtained by fitting each recorded line with the Voigt profile as well as the Rautian profile accounting for the collisional Dicke narrowing effect. The standard Voigt model provides slightly smaller broadening coefficients than the Rautian model. Our data are thoroughly compared to the main atmospheric molecule database HITRAN and previous values in various bands of acetylene. Moreover, it is worth noting that a large number of new transitions not listed in the latest HITRAN08 were measured and identified for the first time.