Background: The São Paulo optical model protocol (SP-OMP) has been developed [Alvarez et al., Phys. Rev. C 100, 064602 (2019); Garrido-Gómez, Vegas-Díaz, Fernández-García, and Alvarez, ibid. 109, 054608 (2024); Garrido-Gómez et al., ibid. 112, 064602 (2025)] with the aim of establishing a common background to describe stable tightly and weakly bound nuclei reactions. This protocol consists of applying four optical model (OM) variants, based on the second version of the double-folding (DF) São Paulo potential (SPP2) [Chamon, Carlson, and Gasques, Comput. Phys. Commun. 267, 108061 (2021)], and the respective optical potentials (OP), to reproduce experimental nuclear-reaction data. The protocol includes a ${\chi }_{\text{red}}^2$ heat map that defines the correlation between real and imaginary OP strengths, their uncertainties, and the sensitivity of the data to them. The OP is applied to microscopic coupled-channel (CC) calculations.

Purpose: This work presents new experimental data for the elastic- and inelastic-scattering angular distributions of ${}^{12}\mathrm{C}+{}^{64}\mathrm{Zn}$, at bombarding energies near the Coulomb barrier ($V_B$ $\approx$ 30 MeV). Data were obtained at three bombarding energies: $E_{\text{lab}}=29.9$, 35.8, and 40.0 MeV. We perform and present the SP-OMP analysis and CC calculations.

Method: From the SP-OMP analysis, we determine the best-fit OPs. The OPs are then applied to the CC calculations. The theoretical OM analysis and CC calculations are compared to the experimental elastic- and inelastic-scattering angular distributions of ${}^{12}\mathrm{C}+{}^{64}\mathrm{Zn}$.

Results: The calculations provide an overall description of the data. The SP-OMP effectively describes the elastic-scattering cross sections of ${}^{12}\mathrm{C}+{}^{64}\mathrm{Zn}$. The CC calculations corroborate the OM analysis, highlighting the main importance of taking into account the first $2^{+}$ and $3^{-}$ excited states of the ${}^{64}\mathrm{Zn}$ target. In addition, we study the importance of coupling the first $2^{+}$ excited state of the ${}^{12}\mathrm{C}$ projectile, which shows to play an important role as the bombarding energy increases.

Conclusion: The application of SP-OMP analysis combined with microscopic CC calculations allows for a better and complementary understanding of the dynamics of ${}^{12}\mathrm{C}$ nuclear reactions as a function of the bombarding energy. The results should contribute to further discriminate between reactions with tightly and weakly bound stable nuclei.

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• Direct reactions
• Elastic scattering reactions
• Nuclear reactions