Spectral averaged cross sections as a probe to a high energy tail of ²³⁵U PFNS

The systematic evaluations of spectrum averaged cross sections dosimetric reactions over a broad range energies were performed in 252 Cf (spontaneous fission) and 235 U(n th ,f) neutron fields. sources used this study LR-0, VR-1 zero power research light water reactors, LVR-15 10 MW reactor, source with emission specified precisely by the manganese sulphate bath. All spectral inferred from measured reaction rates which derived gamma spectrometry. These spectrometry measurements using single detector all cases. ratios U can be to specify high energy tail prompt fission as spontaneous is considered standard. Furthermore, are independent section uncertainties since eliminated. Theoretical models tested based on our measurements. calculations MCNP6.2 transport code different spectra IRDFF-II for threshold reactions. good agreement only ENDF/B-VIII.0 suggesting it harder than other evaluations.