The spallation neutrons were produced by the irradiation of Pb with 250 MeV
protons. The Pb target was surrounded by water which was used to slow down the
emitted neutrons. The moderated neutrons in the water bath were measured by
using the resonance detectors of Au, Mn and In with Cd cover. According to the
measured activities of the foils, the neutron flux at different resonance
energy were deduced and the epithermal neutron spectra were proposed.
Corresponding results calculated with the Monte Carlo code MCNPX were compared
with the experimental data to check the validity of the code.Comment: 6 pages,9 figure