Analysis of the instrumental line shape of high-resolution fourier transform IR spectrometers with gas cell measurements and new retrieval software.

The instrumental line shape (ILS) of two commercial high-resolution Fourier transform IR spectrometers has been analysed with gas cell measurements and a new ILS retrieval software LINEFIT. The instruments are used for atmospheric remote sounding, and the compatibility of the ILS deduced from laboratory gas cell measurements with the ILS in the atmospheric measurement itself is examined.