Absolute intensities in the ν7 band of ethylene: tunable laser measurements used to calibrate FTS broadband spectra

Abstract Three independent measurements of ν7 ethylene transitions at two different laboratories yield direct determinations of absolute intensity for 13 transitions. The 13 intensities are used to calibrate the intensities of a broadband high-resolution 10 μm spectrum of ethylene taken at the McMath Solar Telescope FTS facility. The least-squares fitting of the FTS intensity observations to the precisely determined TDL intensities results in validation of the broadband data for which sample pressure and temperature were marginally known. This “calibration” of the FTS spectrum makes it possible to determine intensities of transitions in several bands in the 800–1100 cm−1 broadband FTS spectrum.