Screening effects on ¹²C+¹²C fusion reaction

Abstract: One of the important reactions for nucleosynthesis in the carbon burning phase in high-mass stars is the ¹²C+¹²C fusion reaction. In this study, we investigate the influences of the nuclear potentials and screening effect on astrophysically interesting ¹²C+¹²C fusion reaction observables at sub-barrier energies by using the microscopic α-α double folding cluster (DFC) potential and the proximity potential. In order to model the screening effects on the experimental data, a more general exponential cosine screened Coulomb (MGECSC) potential including Debye and quantum plasma cases has been considered in the calculations for the ¹²C+¹²C fusion reaction. In the calculations of the reaction observables, the semi-classical Wentzel-Kramers-Brillouin (WKB) approach and coupled channel (CC) formalism have been used. Moreover, in order to investigate how the potentials between ¹²C nuclei produce molecular cluster states of ²⁴Mg, the normalized resonant energy states of ²⁴Mg cluster bands have been calculated for the DFC potential. By analyzing the results produced from the fusion of ¹²C+¹²C, it is found that taking into account the screening effects in terms of MGECSC is important for explaining the ¹²C+¹²C fusion data, and the microscopic DFC potential is better than the proximity potential in explaining the experimental data, also considering that clustering is dominant for the structure of the ²⁴Mg nucleus.