Speaker
Description
The elements beyond iron are predominantly synthesised in neutron capture processes, namely the s- and r-processes. The classical r-process adequately explains the abundance peaks observed at A ~ 130 and A ~ 195 [1], however, the enhancement of the elements with Z = 38-47 (Sr-Ag) indicate the presence of another nucleosynthesis process, the weak r-process, which could occur in neutrino-driven winds. In the weak r-process (α,xn) reactions play a major role in the nucleosynthetic flow in this region, producing neutron-rich isotopes. Modelling the weak r-process nucleosynthesis requires an extended reaction network calculation, with many nuclear input parameters. Sensitivity studies have identified the inaccurate knowledge on the low energy behaviour of the α-nucleus optical potential (OMP) as the main source of uncertainty in the reaction network calculations [2,3].
In order to provide more accurate nuclear physics data for model calculations, we initiated a new systematic study to examine potential parameterizations (of α-OMPs). As the first step of this measurement series, we investigated the 88Sr(α,α)88Sr elastic scattering. High-precision experimental data can be used to determine the total alpha induced reaction cross sections at multiple energies, by fitting the parameters of the local α-OMPs. The parameters of the local potentials were also used to test the global α-OMP parameterizations.
In my poster, I will present our newly measured cross section data on 88Sr, derived by alpha scattering experiments, which were compared with direct measurement results and global α-OMP predictions [4]. Our experimental approach and the preliminary results of the 82Se+alpha scattering experiment will also be presented.
[1] J. J. Cowan et al., Rev. Mod. Phys. 93, 015002 (2021).
[2] J. Pereira et al., Phys. Rev. C 93, 034611 (2016).
[3] P. Mohr, Phys. Rev. C 94, 035801 (2016).
[4] Z. Kóródi et al., Phys. Rev. C - submitted