New results on proton-induced reactions on vanadium for ${}^{47}\mathrm{Sc}$ production and the impact of level densities on theoretical cross sections

New data for the ${}^{\text{nat}}\mathrm{V}(p,x)$ reactions have been measured in the range 26–70 MeV, with production of the nuclides ${}^{47}\mathrm{Sc}, {}^{43}\mathrm{Sc}, {}^{44m}\mathrm{Sc}, {}^{44g}\mathrm{Sc}, {}^{46}\mathrm{Sc}, {}^{48}\mathrm{Sc}, {}^{42}\mathrm{K}, {}^{43}\mathrm{K}, {}^{48}\mathrm{V}, {}^{48}\mathrm{Cr}, {}^{49}\mathrm{Cr}$, and ${}^{51}\mathrm{Cr}$. The focus is on the production of ${}^{47}\mathrm{Sc}$, a ${\beta }^{-}$ emitter suitable for innovative radiotheranostic applications in nuclear medicine. The measured cross sections for this radionuclide and its contaminants are compared with the theoretical excitation functions calculated with the talys code. In view of novel radiopharmaceutical applications, it is essential to accurately describe these cross sections for the evaluation of yields, purities, and dose releases. Hence, we optimize the level-density parameters of the microscopic models in the talys code to obtain the best possible descriptions of the new data. We consider different irradiation conditions to estimate the production yields from the cross sections determined in this paper.

Figure 1

Stacked-foils structure.

Figure 2

${}^{47}\mathrm{Sc}$ cross section.

Figure 3

${}^{43}\mathrm{Sc}$ cross section.

Figure 4

${}^{44g}\mathrm{Sc}$ cross section.

Figure 5

${}^{44m}\mathrm{Sc}$ cross section.

Figure 6

${}^{46}\mathrm{Sc}$ cross section. The ${}^{46t}\mathrm{Sc}$ notation indicates the cumulative cross section due to the formation of the metastable (half-life: 18.75 s) and ground state of ${}^{46}\mathrm{Sc}$.

Figure 7

${}^{48}\mathrm{Sc}$ cross section.

Figure 8

${}^{42}\mathrm{K}$ cross section.

Figure 9

${}^{43}\mathrm{K}$ cross section.

Figure 10

${}^{48}\mathrm{V}$ cross section.

Figure 11

${}^{48}\mathrm{Cr}$ cross section.

Figure 12

${}^{49}\mathrm{Cr}$ cross section.

Figure 13

${}^{51}\mathrm{Cr}$ cross section. The plot below 25 MeV only shows the IAEA recommended evaluation, which represents a guide for the copious number of data measured around the peak.

Figure 14

${}^{51}\mathrm{Cr}$ cross section.

Figure 15

${}^{45}\mathrm{Sc}$ cross section.

Figure 16

Comparison of the observed cumulative levels with the theoretical models discussed in the text.

Figure 17

Threshold of the ${}^{\text{nat}}\mathrm{V}(p,x){}^{47}\mathrm{Sc}$ cross section.

Figure 18

Threshold of the ${}^{\text{nat}}\mathrm{V}(p,x){}^{46}\mathrm{Sc}$ cross section.