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The cross-sections of the 187Re(n,γ)188mRe and 187Re(n,γ)188gRe reactions were measured at the four neutron energies of 13.5, 14.1, 14.4 and 14.8 MeV through the activation method and using off-line γ-ray spectrometry. The previously developed formulas were used to subtract the effects of γ rays with close energies and the contribution from the excited state. A high-resolution γ-ray spectrometer with high-purity germanium detector was used to measure the induced γ activities. The simulation computations of the excitation functions concerning the above-mentioned two nuclear reactions were performed by adopting the nuclear theoretical model program system Talys-1.9. The theoretical excitation curves in the incident neutron energy range from 2.53 × 10−8 to 20 MeV were acquired. The fitting line of our results in the neutron energy range of 13.5–14.8 MeV, within experimental uncertainty, agrees very well with the theoretical excitation curve based on the computer code Talys-1.9.

The first experimental cross-section data for the 180Hf(n,γ)181Hf reaction have been measured within the neutron energies range of 13.5–14.8 MeV using the activation technique. The fast neutrons were produced by the T(d,n)4He reaction. Induced activities were measured by a high-resolution γ-ray spectrometer with high-purity germanium detector. The neutron fluence was determined by using the monitor reaction 93Nb(n,2n)92mNb. The neutron energies in the measurements were determined beforehand by the method of cross section ratios for the 90Zr(n,2n)89m+gZr and 93Nb(n,2n)92mNb reactions. The experimentally determined cross-section values were compared with the evaluation nuclear data in several major libraries of International Atomic Energy Agency and the theoretically calculated results by using the Talys1.8 code.

Cross-section data of the 185Re(n,2n)184mRe, 185Re(n,2n)184gRe, 185Re(n,α)182m1+m2+gTa, 187Re(n, 2n)186g,(m)Re, 187Re(n,α)184Ta, and 187Re(n,p)187W reactions were measured at four neutron energies, namely 13.5, 14.1, 14.4, and 14.8 MeV, by means of the activation technique, relative to the reference cross-section values of the 93Nb(n,2n)92mNb reaction. The neutrons were generated from the T(d,n)4He reaction at the K-400 Neutron Generator at China Academy of Engineering Physics. The induced γ activities were measured using a high-resolution γ-ray spectrometer equipped with a coaxial high-purity germanium detector. The excitation functions of the six above-mentioned nuclear reactions at neutron energies from the threshold to 20 MeV were calculated by adopting the nuclear theoretical model program system Talys-1.9 with the relevant parameters properly adjusted. The measured cross sections were analyzed and compared with previous experiments conducted by other researchers, and with the evaluated data of BROND-3.1, ENDF/B-VIII.0, JEFF-3.3, and the theoretical values based on Talys-1.9. The new measured results agree with those of previous experiments and the theoretical excitation curve at the corresponding energies. The theoretical excitation curves based on Talys-1.9 generally match most of experimental data well.

The cross sections for the 94Zr(n,d*)93m+gY, 96Zr(n,γ)97Z, 96Zr(n,2n)95Zr, 90Zr(n,α)87mSr, 94Zr(n,α)91Sr,90Zr(n,p)90mY, 92Zr(n,p)92Y, and 94Zr(n,p)94Y reactions have been measured in the neutron energy range of 13.5-14.8 MeV by means of the activation technique. The neutrons were produced via the D-T reaction. A high-purity germanium detector with high energy resolution was used to measure the induced γ activities. In combination with the nuclear reaction theoretical models, the excitation curves of the above-mentioned eight nuclear reactions within the incident neutron energy range from the threshold to 20 MeV were obtained by adopting the nuclear theoretical model program system Talys-1.9. The resulting experimental cross sections were analyzed and compared with the experimental data from published studies. Calculations were performed using Talys-1.9 and are in agreement with our experimental results, previous experimental values, as well as results of the theoretical excitation curves at the corresponding energies. The theoretical excitation curves generally match the experimental data well.

In view of the fact that the fast-neutron experimental cross-section data of hafnium which is an important structural material of fusion reactor are few and there are the great differences in their evaluation values, several activation cross sections of (n, 2n), (n, p), (n, a) and (n, n′) reactions on hafnium isotopes have been investigated by neutrons generated from the T(d, n)4He reaction at the K-400 Neutron Generator at China Academy of Engineering Physics (CAEP). The gamma activities of the product nuclei were measured by a high-resolution gamma-ray spectrometer with a coaxial high-purity germanium detector. The 93Nb(n, 2n)92mNb reaction was used as neutron fluence standard, these experimental cross sections of the 174Hf(n, 2n)173Hf, 176Hf(n, 2n)175Hf, 178Hf(n, α)175m+gYb, 178Hf(n, p)178gLu, 178Hf(n, p)178mLu, 180Hf(n, 2n)179m2Hf, 180Hf(n, α)177m+gYb and 180Hf(n, n′)180mHf reactions were obtained in the neutron energy range of 13.5–14.8 MeV. These measured cross sections were discussed and compared with some previous experimental results from the literature and with the evaluation data from ENDF/B-VIII.0, CENDL-3.1, JEFF-3.3 and the theoretical results by using the computer code system Talys-1.9.