Spectral and Temporal Characterization of High-Temperature Events

The remote observations of the temporal and spectral characteristics of the infrared (IR) emissions from exploding ordnance have been correlated with explosion conditions. A Bomem MR-154 Fourier Transform Interferometer with two detectors, InSb and HgCdTe, was used to record spectra in the 1.3 - 20 micrometers range. Data was collected at spectral resolutions of 16/cm and 4/cm, and temporal resolutions of 0.045 sand 0.123 5, respectively. The data files range in size from 900 Kilobytes to several Megabytes. These are reduced to 2- dimensional representations of temporal features that are less than 100 Kilobytes. The data analysis indicates the possibility of characterizing event species through one or more derived temporal features. Each event data matrix contains three dimensions of information describing radiance as a function of frequency and time. The observed data is first corrected for atmospheric losses to convert apparent radiance to emitted radiance. The data is then adjusted to remove background radiance. Finally, the corrected data is fit to a Planckian distribution function to compute event temperature and fractional field of view. Temporal profiles of temperature and fractional field of view are created to describe each event. The temporal profiles of each explosive type are compared to other explosive types. Certain explosive types indicated an afterburn feature on their temperature profiles. The afterburn feature wasn't apparent on the temperature profiles of other types. Additionally, the temporal evolution of fractional field of view was unique for each explosive type.Air Force Inst of Tech Wright-Patterson AFB OH School of Engineering and Management is the author of 'Spectral and Temporal Characterization of High-Temperature Events', published 2001 under ISBN 9781423528142 and ISBN 142352814X.