WIDE-BAND HIGH-RESOLUTION TIME-RESOLVED SPECTROSCOPY

The high-resolution step-scan Fourier transform spectrometer of the Laboratoire de Physique moleculaire et Applications has been modified to record time-resolved spectra. In order to reach high temporal and spectral resolutions, particular attention was paid to the main difficulties associated with the short time available for each data measurement. Solutions to overcome the dynamic-range limitations were proposed and tested. Descriptions of the recording procedures with related simulations are given. In order to appreciate the high information feasibility of time-resolved Fourier transform spectroscopy, Doppler-limited spectra of the electronic transition (BIIg)-I-3-A(3) Sigma(u)(+) of the nitrogen molecule, emitted from a microwave-excited plasma, have been obtained over a range of 7000 cm(-1). They show a two-fold improvement on the total number of samples in a time-resolved Fourier transform spectroscopy experiment.