The cross section of the reaction 112 Sn(α, γ ) 116 Te has been measured in the energy range of astrophysical interest for the p-process. Highly enriched self-supporting 112 Sn foils were bombarded with α beams in the effective center of mass energy range from 7.59 to 11.42 MeV at the Notre Dame FN Tandem Van de Graaff accelerator. The characteristic activity of 116 Te was counted with a pair of large volume Ge clover detectors in close geometry to maximize the detection efficiency. The cross section of the concurrent (α, p) reaction has also been measured. The results are compared with statistical model predictions for different global α-nucleus potentials.

The 106 Cd(α, γ) 110 Sn reaction cross section has been measured in the energy range of the Gamow window for the astrophysical p-process scenario. The cross sections for 106 Cd(α,n) 109 Sn and for 106 Cd(α,p) 109 In below the (α,n) threshold have also been determined. The results are compared with predictions of the statistical model code NON SMOKER using different input parameters. The comparison shows that a discrepancy for 106 Cd(α, γ) 110 Sn when using the standard optical potentials can be removed with a different α+ 106 Cd potential. Some astrophysical implications are discussed.

Erratum: Systematic study of the α-optical potential via elastic scattering near the Z = 50 region for p-process nuclei [Phys. Rev. C 85, 035808 (2012)]

Abstract. The112 Sn(α, γ) 116 Te reaction cross-section has been measured to test the applicability of statistical models, especially NON-SMOKER in the energy range of importance for the astrophysical p-process nucleosynthesis. The measurements were carried out at the Notre Dame FN Tandem

Production of proton-rich nuclei beyond iron in stars proceeds via the p process, i.e., a sequence of photo-disintegration reactions, (γ,n), (γ,p), and (γ,α) on heavy nuclei at temperatures of 2 − 3 × 10 9 K. The involved reaction rates are typically calculated with the statistical Hauser-Feshbach (HF) model. However, the HF model performs poorly in calculating the critical (γ,α) rates due to the uncertainty of the alpha optical potentials applied. To test the reliability of the HF calculations and provide a systematic understanding of the alpha optical potential at energies of astrophysical interest, a series of precision alpha scattering measurements were carried out at the Notre Dame FN Tandem Accelerator. Specifically, 106 Cd, 118 Sn, and 120,124,126,128,130 Te were studied at energies both below and above the Coulomb barrier. A new parametrization of the alpha optical potential was derived of the elastic scattering cross section data. The derived potential was applied for calculating the α-induced reaction cross sections on these nuclei using the HF approach. The results were compared to the corresponding experimental values obtained from previous activation measurements on Cd, Sn, and Te isotopes.