MEASUREMENT OF NEUTRON-PRODUCTION DOUBLE-DIFFERENTIAL CROSS-SECTIONS FOR NUCLEAR SPALLATION REACTION INDUCED BY 0.8, 1.5 AND 3.0 GEV PROTONS

Neutron-production double-differential cross sections were measured fo r the spallation reaction induced by 0.8, 1.5 and 3.0 GeV protons on C , Al, Fe, In and Pb targets. The experiments were performed by time-of -flight technique with a typical flight path length of Im, and the cro ss sections were obtained with energy resolutions better than 8% at ne utron energies below 100 MeV. The experimental data were compared with the results of calculation codes based on an intranuclear-cascade-eva poration model. Adoption of the in-medium effect on nucleon-nucleon cr oss section in the cascade calculation improves the agreement between the calculated results and experimental data particularly in the case of 0.8-GeV proton incidence. For protons above 1 GeV, however, the cal culations typically twice overestimate the cross sections in the emitt ed neutron energy region of 10 to 30 MeV.