Speaker
Description
Understanding the origin of heavy chemical elements in the Universe remains a fundamental challenge. One of the primary mechanisms for forming such heavy nuclei is the rapid neutron capture process (r-process), which can occur during neutron star mergers [1]. In this process, neutrons are captured at high temperatures, leading to the formation of very neutron-rich nuclei.
In the actinide region, nuclear fission begins to compete with the r-process, producing fission fragments that can re-enter and restart the r-process. Detailed models of the r-process require precise data on nuclear fission. However, experimental data on nuclear fission as a function of excitation energy is scarce. Corresponding data can be obtained by fission reactions that are induced either by real photons (photofission) or by virtual photons due to electron scattering (electrofission).
At Technische Universität Darmstadt, a new experimental setup is currently being developed for electron-induced fission, using electron beams in the 100 MeV region produced by the super conducting Darmstadt linear accelerator S-DALINAC [2]. The setup will employ silicon strip detectors for energy and time-resolved detection of both fission fragments, combined with coincident detection of scattered electrons using the QCLAM magnetic spectrometer at the S-DALINAC [2].
This arrangement will enable high-precision measurements of fission fragment masses as a function of excitation energy. An overview of the current status of this project will be presented in this contribution.
The authors acknowledge the support by the State of Hesse within the Research Cluster ELEMENTS (Project ID 500/10.006) and funding from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under project-ID No. 499256822 GRK 2891 "Nuclear Photonics".
[1] J. J. Cowan et al., Rev. Mod. Phys. 93, 015002 (2021)
[2] N. Pietralla, Nucl. Phys. News 28, 4 (2018)
