Laser-Driven Neutron Sources - A Compact Approach to Non-Destructive Material Analysis

Marc Zimmer
2020
Neutrons have become a unique tool for non-destructive testing of materials but despite the increasing interest from science and industry, the number of accessible neutron sources has decreased in the last years due to the phasing out of nuclear research reactors. This creates a strong discrepancy between supply and demand for access to neutron facilities. Laser-Driven Neutron Sources (LDNS) have the potential to fill this gap but so far research on this topic is mostly focused on the neutron
more » ... ed on the neutron production and not on their utilization for material testing. This shortcoming is addressed by this thesis through the development of a setup designed to conduct Neutron Resonance Spectroscopy (NRS) on a laser-driven source. In this process, the question is answered how the involved components have to be optimized to enable this source type to be competitive with established neutron sources. This is accomplished via a meta-analysis on laser ion acceleration, a systematic review process of targetry solutions as well as Monte Carlo (MC) simulations for the neutron generation, moderation and transport. This is followed by an experimental verification of this technique through the identification of the isotopes 182W and 183W inside a tungsten sample. In addition, it was shown that the same setup was capable of determining the sample thickness of a 1mm indium plate behind a 2mm thick lead shield via a thermal neutron radiography. By using MC simulations for state of the art laser systems it was possible to predict the performance of LDNS to be comparable to existing sources while being orders of magnitude smaller in size. These results close the gap between LDNS as a theoretical concept and their application as a tool for material identification.
doi:10.25534/tuprints-00012996 fatcat:rlnwl2z7cbe47h5kmqzqw5fu7i