Cross-section of the ${}^{95}\mathrm{N}\mathrm{b}$ production on natural molybdenum at the bremsstrahlung end-point energy up to 95 MeV

The photoproduction of ${}^{95\mathrm{m}}$Nb on ${}^{\mathrm{n}\mathrm{a}\mathrm{t}}\mathrm{M}\mathrm{o}$ was studied using the electron beam of the LUE-40 linac RDC “Accelerator” NSC KIPT. Measurements were performed using activation and off-line $\gamma$-ray spectrometric techniques. The experimental flux-averaged cross-section $⟨\sigma (E_{\gamma \mathrm{m}\mathrm{a}\mathrm{x}}){⟩}_{\mathrm{m}}$ for the ${}^{\mathrm{n}\mathrm{a}\mathrm{t}}\mathrm{M}\mathrm{o}(\gamma ,x\mathrm{n}\mathrm{p}{)}^{95\mathrm{m}}$Nb reaction at the bremsstrahlung end-point energy range of 38–93 MeV has been first time obtained. The estimated values $⟨\sigma (E_{\gamma \mathrm{m}\mathrm{a}\mathrm{x}}){⟩}_{\mathrm{g}}$ for the formation of ${}^{95}$Nb in the ground state and total cross-sections $⟨\sigma (E_{\gamma \mathrm{m}\mathrm{a}\mathrm{x}}){⟩}_{\mathrm{t}\mathrm{o}\mathrm{t}}$ for the studied reaction were determined. The theoretical values of the yields $Y_{\mathrm{m},\mathrm{g},\mathrm{t}\mathrm{o}\mathrm{t}}(E_{\gamma \mathrm{m}\mathrm{a}\mathrm{x}})$ and flux-averaged cross-sections $⟨\sigma (E_{\gamma \mathrm{m}\mathrm{a}\mathrm{x}}){⟩}_{\mathrm{m},\mathrm{g},\mathrm{t}\mathrm{o}\mathrm{t}}$ for the ${}^{\mathrm{n}\mathrm{a}\mathrm{t}}\mathrm{M}\mathrm{o}(\gamma ,x\mathrm{n}\mathrm{p}{)}^{95\mathrm{m},\mathrm{g},\mathrm{t}\mathrm{o}\mathrm{t}}$Nb reactions were calculated using the cross-sections $\sigma (E)$ from the TALYS1.95 code for six different level density models. The comparison showed a significant excess of the experimental results over the theoretical $⟨\sigma (E_{\gamma \mathrm{m}\mathrm{a}\mathrm{x}}){⟩}_{\mathrm{m},\mathrm{g},\mathrm{t}\mathrm{o}\mathrm{t}}$ values.