Abstract

The process of photoproduction of a series of radioisotopes from copper nuclei at the bremsstrahlung end-point energies \(E_{\gamma }^{{\max }}\) = 21, 30, and 40 MeV was studied at the AANL (YerPhI) linear electron accelerator. The relative yields of ⁶¹Co, ⁶⁰Co, ⁵⁸Co, ⁵⁷Co with respect to the ⁶¹Cu are measured; in particular, at \(E_{\gamma }^{{\max }}\) = 40 MeV they are equal to (2.6 ± 0.3) × 10^–2, (2.67 ± 0.04) × 10^–2, (9.3 ± 0.6) × 10^–2, and (0.76 ± 0.04) × 10^–2, respectively. It is shown that the predictions of the TALYS model, as well as the model inserted in the GEANT4 software package are in a contradiction (especially in the case of the GEANT4 code) with the measured relative yields. A continuously decreasing energy dependence was observed for the ratio of unfolded (weighted with the bremsstrahlung spectrum) cross-sections of reactions ⁶⁵Cu(γ,α)⁶¹Co and ⁶³Cu (γ,2n)⁶¹Cu, similarly to that observed earlier for the ratio of cross-sections of electronuclear reactions ⁶⁵Cu(e,e′ + α)⁶¹Co and ⁶³Cu (e, e′ + 2n)⁶¹Cu. The ratio of the ⁶¹Co and ⁶⁴Cu yields is also measured, being equal to (2. 6± 0.2)×10^–3, (3.8 ± 0.6) × 10^–3, and (3.2 ± 0.4) × 10^–3, respectively, at \(E_{\gamma }^{{\max }}\) = 21 MeV, 30 MeV, and 40 MeV; its value (2.6 ± 0.2) × 10^–3 at \(E_{\gamma }^{{\max }}\) = 21 MeV is consistent with the general trend of the dependence of this ratio on the atomic number Z, measured recently at \(E_{\gamma }^{{\max }}\) = 23 MeV for heavier nuclei with the atomic numbers from Z = 47 to Z = 82.

中文翻译：

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铜核中钴放射性同位素的光生产研究

摘要

在AANL（YerPhI）上研究了铜copper在the致辐射终点能量\（E _ {\ gamma} ^ {{\ max}} \） = 21、30和40 MeV处产生一系列放射性同位素的过程。 ）线性电子加速器。测量相对于⁶¹ Cu的⁶¹ Co，⁶⁰ Co，⁵⁸ Co，⁵⁷ Co的相对产率；特别是，在\（E _ {\ gamma} ^ {{\\ max}} \） = 40 MeV时，它们等于（2.6±0.3）×10 ^–2，（2.67±0.04）×10 ^–2，（9.3± 0.6）×10 ^–2和（0.76±0.04）×10 ^–2， 分别。结果表明，TALYS模型的预测以及插入GEANT4软件包中的模型与测得的相对产量存在矛盾（尤其是在GEANT4代码的情况下）。观察到反应⁶⁵ Cu（γ，α）⁶¹ Co和⁶³ Cu（γ，2n）⁶¹ Cu的未折叠截面（用weight致辐射谱加权）的比例不断降低的能量依赖性，与之前观察到的类似。电子核反应的横截面比率⁶⁵ Cu（e，e'+α）⁶¹ Co和⁶³ Cu（e，e'+ 2n）⁶¹ Cu。⁶¹ Co与⁶⁴ Co的比率产率的Cu也被测量，等于（2.6±0.2）×10 ^-3，（3.8±0.6）×10 ^-3，和（3.2±0.4）×10 ^-3，分别在\（E _ {\ γ} ^ {{{\ max}} \） = 21 MeV，30 MeV和40 MeV；其值（2.6±0.2）×10 ^–3在\（E _ {\ gamma} ^ {{\\ max}} \） = 21 MeV时与该比率对原子序数Z的依赖关系的总体趋势一致，最近在\（E _ {\ gamma} ^ {{\\ max}} \） = 23 MeV时，较重原子核的原子序数从Z = 47到Z = 82。