26Si(p, γ) 27P direct proton capture by means of the asymptotic normalization coefficients method for mirror nuclei

The Si-26(p, gamma) P-27 reaction might be relevant in understanding the Si-26 depletion and Al-26 production in stars. The asymptotic normalization coefficients (ANC) for the Si-26(p, gamma) P-27 reaction were extracted earlier from the reanalysis of Mg-26(d, p)Mg-27 and Mg-26(t, d)Mg-27 reactions, in which the deduced ANC's show significant discrepancies. In this work, a dedicated (d, p) measurement is presented: the ANC for the Mg-27 -> Mg-2(6) + n virtual decay is deduced from the Mg-26(d, p)Mg-27 reaction populating the ground and the first excited state of Mg-27 using the distorted wave Born approximation (DWBA). The charge symmetry properties for mirror nuclei have been used to calculate the ANC for the direct capture Si-26 + p -> P-27 populating the ground state of P-27. By means of the same formalism, the Gamma(p) width for the first excited state has also been deduced. The reaction rate is also updated using recent values for the Gamma(gamma)/Gamma(p) ratio measured by [Sun et al., Phys. Rev. C 99, 064312 (2019); Sun et al., Phys. Lett. B 802, 135213 (2020)].

Automated summary

The Si-26(p, gamma) P-27 reaction is important for understanding the Si-26 depletion and Al-26 production in stars. In this study, the asymptotic normalization coefficients (ANC) for this reaction were extracted from experimental data, and the reaction rate was updated using recent measurements of the Gamma(gamma)/Gamma(p) ratio. Additionally, charge symmetry properties for mirror nuclei were utilized to calculate the ANC for the direct capture Si-26 + p -> P-27 reaction.