Unfolding of ²³⁹Pu-Be and ²⁵²Cf neutron energy spectra using passive multi-layer neutron spectrometer

In the study, the passive multi-layer neutron spectrometer, based on thermoluminescence detectors, was tested in a calibration laboratory with ²³⁹Pu-Be and ²⁵²Cf isotopic sources. MCNP code was used for the calculation of the response functions for the neutron energy range from 1 meV to 100 MeV. It was also utilised for initial guess spectra calculations. Deconvolution was performed with MAXED and GRAVEL deconvolution codes resulting in the neutron spectra defined at the measuring point in the calibration laboratory. (authors)