CALIBRATION OF A NEUTRON SPECTROMETER IN THE ENERGY-RANGE 144 KEV TO 14.8 MEV WITH ISO ENERGIES

For calibration purposes measurements were performed with the neutron spectrometer system ROSPEC (gas proportional counters) and SSS (plasti c scintillation detector) at ISO energies from 144 keV to 14.8 MeV. Th e spectrometer ROSPEC consists of four spherical proportional counters filled at different pressures to cover the complete energy range from 50 keV to 4.5 MeV. The SSS extends the energy range from 4 MeV to 15 MeV. The experimental data prove that both instruments are able to rep roduce the nominal neutron energies within an accuracy of less than 8% . The fluence measurements show in the energy range from 50 keV to 2.5 MeV a systematic overestimation of approx. 6% of the absolute neutron fluences. Between 4.2 MeV and 14 MeV these systematic deviations are below 88 and above 14 MeV those deviations are completely within the s tatistical error of less than 3%.