Abstract
The ν1 + ν3 band of 12C2H2 was recorded using a high resolution continuous scan Fourier transform interferometer fitted with a femto OPO absorption source. Various experimental schemes were successfully implemented, including multipass absorption in a cell and also in a supersonic expansion, and cavity enhanced absorption. An optimal rms noise equivalent absorption of 2.2 × 10−9 cm−1 Hz−1/2 per spectral element was reached in the latter case, corresponding to αmin = 1.5 × 10−7 cm−1. Performances are illustrated and discussed.
Acknowledgments
We are happy to dedicate this paper to Professor Di Lonardo, for his many contributions to the acetylene spectroscopy, a dedication shared with all of us. We thank B. Amyay and P. Van Poucke (ULB) for their help on various items. We are indebted to the ‘programme Currien/Tournesol’ collaboration sponsored by ‘Wallonie Bruxelles international’, F.R.S.-FNRS and ‘Région Wallone’, and ‘Ministère des Affaires étrangères’ and ‘Ministère de l’Education Nationale, de la Recherche et de la Technologie’ on the Belgian and French sides, respectively. This work was also sponsored in Belgium, by the Fonds National de la Recherche Scientifique (FNRS, contracts FRFC and IISN) and the ‘ Action de Recherches Concertées de la Communauté française de Belgique’.