Neutron-based methods of non-destructive inter- rogation of objects for the purpose of their characterization are well-established techniques, employed in the field of bulk material analysis, contraband detection, unexploded ordnance, etc. The characteristic gamma rays produced in nuclear reactions initiated by neutrons in the volume of the irradiated object (inelastic neutron scattering, thermal neutron capture, and activation) are used for the elemental identification. In many real-world applications, an automated spectral analysis is needed, and many algorithms are used for that purpose. The Applied Physics Institute at Western Kentucky University has recently started to employ a mathematical spectrum analysis technique based on wavelets that simultaneously provides quick, accurate, and objective analysis of gamma ray spectra.

This paper will provide a brief overview of wavelets and multiwavelets, and of the wavelet-based analysis algorithm. Examples will be given using neutron- induced photon spectra measured using high resolution and low resolution detectors.