Synthesis of neutron-rich transuranic nuclei in fissile spallation targets

TL;DR

This paper explores the potential of producing neutron-rich transuranic nuclei in spallation targets within Accelerator Driven Systems, using simulations to evaluate isotope synthesis and suggest design optimizations for enhanced production.

Contribution

The study introduces Nuclide Composition Dynamics (NuCoD), a new simulation tool for modeling isotope evolution in spallation targets during long-term irradiation.

Findings

Transuranic elements up to Bk-249 can be produced in significant quantities.

Current neutron fluxes are insufficient to overcome the fermium gap.

Design improvements like moderators and reflectors could make ADS a viable source of transuranic elements.

Abstract

A possibility of synthesizing neutron-reach super-heavy elements in spallation targets of Accelerator Driven Systems (ADS) is considered. A dedicated software called Nuclide Composition Dynamics (NuCoD) was developed to model the evolution of isotope composition in the targets during a long-time irradiation by intense proton and deuteron beams. Simulation results show that transuranic elements up to Bk-249 can be produced in multiple neutron capture reactions in macroscopic quantities. However, the neutron flux achievable in a spallation target is still insufficient to overcome the so-called fermium gap. Further optimization of the target design, in particular, by including moderating material and covering it by a reflector will turn ADS into an alternative source of transuranic elements in addition to nuclear fission reactors.