Time-resolved Fourier transform infrared spectroscopy: Application to pulsed discharges

Time-resolved Fourier transform spectroscopy (TR-FTS) is reviewed, with emphasis on synchronous FTS using continuously scanning interferometers. By using a high-resolution Bruker IFS 120 HR, a TR-FTS method has been developed with the help of a microcontroller SX, where a maximum of 64 time-resolved data are recorded with a preset time interval in a single scan of the interferometer. The time resolution is 1 mu s, limited by the response time of the detector system used. This method has been applied to a pulsed discharge in an Ar and H-2 Mixture to observe time profiles of ArH+ and ArH emission spectra. Electronic transitions of He-2 have been observed in the infrared region with this method, and from the time profiles, He-2 in Rydberg states with higher energy than the b(3)Pi, state is found to be produced efficiently in afterglow plasma. Fifteen bands in the 2300-8000 cm(-1) region have been assigned by using previously reported data from the optical region. A new band from the 5f state has been assigned for the first time through the 5f-4d band in the 2600 cm(-1) region. (c) 2005 Elsevier Inc. All rights reserved.