Abstract
About 50% of the elements heavier than iron are produced during the slow neutron capture process. This process occurs in different stellar sites at various energies. To understand the ongoing nucleosynthesis, the probability of a neutron capture for different temperatures and therefore for different stellar sites is essential. Activation experiments using the 7Li(p,n) reaction as neutron source were performed. At a temperature of kBT = 25 keV the cross sections were determined for 27Al, 37Cl and 41K. A new method was developed to perform activation experiments at even lower temperatures. For a proof of principle, the cross section for 64Ni was measured at kBT = 25 keV as well as for kBT = 6 keV. To study the impact of isomeric states at higher energies, activations of 181Ta were performed using two different proton energies.
Highlights
The slow neutron capture process (s-process) synthesizes about 50% of the heavy elemental abundances
Isomeric states can have a big impact at the nucleosynthesis path [3]
Many neutron capture measurements are only sensitive to the sum of the cross sections population of the isomeric and ground state
Summary
The slow neutron capture process (s-process) synthesizes about 50% of the heavy elemental abundances. Two neutron sources acting temperature dependent: 13C(α,n) at kBT = 5 keV and 22Ne(α,n) at kBT = 30 keV [1]. The working horse for activation measurements at kBT = 25 keV is the 7Li(p,n) reaction as neutron source. At this temperature measurements for 27Al to study the puzzle of active nucleosynthesis [2] as well as 37Cl and 41K, which act as neutron poisons [1] were performed. In order to investigate cross sections at lower temperatures, a new method for activation measurements at kBT = 6 keV was developed. Many neutron capture measurements are only sensitive to the sum of the cross sections population of the isomeric and ground state. In order to study the neutron capture into the isomeric state at higher temperatures, a measurement of neutron capture on 181Ta into the isomeric and ground state of 182Ta was performed using higher proton energies
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
