Premium
Energy transfer from optoacoustic measurements and fourier transform deconvolution
Author(s) -
Braun W.,
Price I.,
Cadoff B. C.,
Peterson N. C.
Publication year - 1989
Publication title -
international journal of chemical kinetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.341
H-Index - 68
eISSN - 1097-4601
pISSN - 0538-8066
DOI - 10.1002/kin.550211106
Subject(s) - deconvolution , waveform , convolution (computer science) , chemistry , fourier transform , relaxation (psychology) , laser , energy (signal processing) , pulse (music) , optics , physics , mathematical analysis , mathematics , psychology , social psychology , machine learning , detector , artificial neural network , computer science , quantum mechanics , voltage
Abstract The rate of V → R , T energy relaxation following pulsed ir laser excitation is measured by employing an optoacoustic single pulse method. Under present experimental conditions the operation of convolution applies. The experimental optoacoustic waveform can be viewed as the convolution of the kinetic relaxation waveform with an optoacoustic waveform obtained under very fast energy relaxation conditions. A discrete Fourier transform deconvolution method is applied to optoacoustic measurements on SF 6 in argon to obtain the time constant, τ, for energy transfer. The present method gives τ P = 182 ± 15 μs torr, in good agreement with other methods. These results were obtained without requiring either a theoretical description of the pressure waveform or an assumed laser irradiation geometry. For convolution to apply, the differential equation describing the pressure pulse must be linear under the conditions of the experiment. The linearity of the system can usually be tested experimentally.