Measurement of 25.5 MeV Neutron Fluence Rate With ²³⁸U Fission Chamber

Based on the neutron energy spectrum measured with a time-of-flight neutron spectrometer, the 25.5 MeV neutron fluence rate was measured with ²³⁸U fission chamber at the HI-13 tandem accelerator in CIAE (China Institute of Atomic Energy). To verify the reliability of the fission chamber for measuring fast neutron fluence rate, the 14.8 MeV neutron fluence rate was measured simultaneously with the fission chamber and the association α particle instrument at the 5SDH-2 tandem accelerator in CIAE, of which results are coincident within the uncertainties.