Exploring laser-driven neutron sources for neutron capture cascades and the production of neutron-rich isotopes

Abstract

The production of neutron-rich isotopes and the occurrence of neutron capture cascades via laser-driven (pulsed) neutron sources are investigated theoretically. The considered scenario involves the interaction of a laser-driven neutron beam with a target made of a single type of seed nuclide. We present a comprehensive study over 95 seed nuclides in the range 3≤Z≤100 from Li37 to Fm100255. For each element, the heaviest sufficiently long-lived (half-life >1 h) isotope whose data is available in the recent ENDF-B-VIII.0 neutron sublibrary is considered. We identify interesting seed nuclides with good performance in the production of neutron-rich isotopes where neutron capture cascades may occur. The effects of the neutron number per pulse, the neutron-target interaction size, and the number of neutron pulses are also analyzed. Our results show the possibility of observing up to four successive neutron capture events, leading to neutron-rich isotopes with four more neutrons than the original seed nuclide. This hints at experimental possibilities to produce neutron-rich isotopes and simulate neutron capture nucleosynthesis in the laboratory. With several selected interesting seed nuclides in the region of the branching point of the s-process (Sb51126, Lu71176, and Re75187) or the waiting point of the r-process (Lu, Re, Os, Tm, Ir, and Au), we expect that laser-driven experiments can shed light on our understanding of nucleosynthesis.