MEASUREMENTS OF THE RESPONSE FUNCTION AND THE DETECTION EFFICIENCY OFAN NE213 SCINTILLATOR FOR NEUTRONS BETWEEN 20 AND 65 MEV

For neutrons 25, 30 and 65 MeV, the response functions and detection e fficiencies of an NE213 liquid scintillator were measured. Quasi-monoe nergetic neutrons produced by the Li-7(p,n(0,1)) reaction were employe d for the measurement and the absolute flux of incident neutrons was d etermined within 4% accuracy using a proton recoil telescope. Response functions and detection efficiencies calculated with the Monte Carlo codes, CECIL and SCINFUL, were compared with the measured data. Ir was found that response functions calculated with SCINFUL agreed better w ith experimental ones than those with CECIL, however, the deuteron lig ht output used in SCINFUL was too low. The response functions calculat ed with a revised SCINFUL agreed with the experimental ones quite well even for the deuteron bump and peak due to the C(n,d(0)) reaction. It was confirmed that the detection efficiencies calculated with the ori ginal and the revised SCINFULs agreed with the experimental data withi n the experimental error, while those with CECIL were about 20% higher in the energy region above 30 MeV.