Estimation of neutron energy spectra with bubble detectors. Potential and limitations

The capabilities of neutron bubble detectors to give limited energy information have been investigated with neutrons from 252Cf and D-T sources. The Bubble Detector Spectrometer (BDS) with six different energy thesholds ranging from 10 keV to 10 MeV has been used. The data obtained with the 252Cf source have been compared with data from measurements with the neutron spectrometer ROSPEC. In addition the data have been compared with theoretical calculations. The agreement between the measured BDS data with the californium source and theory was acceptable. For the measurements at the 14 MeV D-T neutron generator a deconvolution of the bubble data has not been possible, therefore the doses calculated from the number of bubbles produced in the detectors are given. There is a clear indication of neutrons with energies higher than 10 MeV. For these neutron energies the fluence is measured correct within an error of 15 per cent