Speaker
Description
An important step in understanding the origin of life is to study stellar nucleosynthesis. The abundance of elements up to iron is produced almost exclusively through nuclear fusion, whereas most heavy elements are formed via neutron capture in the s- and r-processes. The s-process occurs inside the shell burning of massive stars, while the r-process requires extreme conditions, like type II supernovae or neutron star mergers.Krypton plays a vital role in the s-process due to the branching points of 81Kr and 85Kr. These branching points are nuclei where the decay rate is in the order of the neutron capture rate, rβ ≈ rn. To gain insight into these points, it is crucial to study the (n, γ) reaction and how these nuclei behave under stellar conditions. For the activation measurements, natural krypton samples were produced and prepared for irradiation. Due to the gaseous nature of krypton, the sample production and preparation represent an important experimental part of the measurement. The cross-sections for the 78Kr(n, γ)79Kr and 84Kr(n, γ)85mKr reactions could be determined at various temperatures using the activation method. The sample production, experimental procedure, resulting values and outlook will be presented.