Abstract
The Monte Carlo code, designeted SCINFUL-QMD, has been developed to calculate neutron detection efficiency up to 3 GeV for liquid organic scintillators such as NE-213. The existing Monte Carlo code, SCINFUL, is known to reproduce a response function and detection efficiency at incident neutron energies below 80 MeV. We incorporate the quantum molecular dynamics plus statistical decay model (QMD+SDM) into SCINFUL to extend the upper limit of incident neutron energy to 3 GeV. The results by SCINFUL-QMD are compared with experimental data and those of CECIL. The SCINFUL-QMD exhibits an increase in detection efficiency above 300 MeV. This tendency agrees with one of the experimental data. The increase is achived by taking charged pion production into account.