It is a well-observed result that different nuclear input models sensitively affect Hauser-Feshbach (HF) crosssection calculations. Less well-known, however, are the effects on calculations originating from nonmodel aspects, such as experimental data truncation and transmission function energy binning, as well as code-dependent aspects, such as the definition of level-density matching energy and the inclusion of shell correction terms in the level-density parameter. To investigate these aspects, Maxwellian-averaged neutron capture cross sections (MACS) at 30 keV have been calculated using the well-established statistical Hauser-Feshbach model codes TALYS and NON-SMOKER for approximately 340 nuclei. For the same nuclei, MACS predictions have also been obtained using two new HF codes, CIGAR and SAPPHIRE. Details of these two codes, which have been developed to contain an overlapping set of identically implemented nuclear physics input models, are presented. It is generally accepted that HF calculations are valid to within a factor of 3. It was found that this factor is dependent on both model and nonmodel details, such as the coarseness of the transmission function energy binning and data truncation, as well as variances in details regarding the implementation of level-density parameter, backshift, matching energy, and giant dipole strength function parameters.

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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)]

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.