Award Date
12-1-2020
Degree Type
Thesis
Degree Name
Master of Science in Engineering (MSE)
Department
Mechanical Engineering
First Committee Member
Alexander Barzilov
Second Committee Member
Yi-Tung Chen
Third Committee Member
William Culbreth
Fourth Committee Member
Emma Regentova
Number of Pages
97
Abstract
The purpose of this research was to analyze the capabilities of fast neutrons in the detection and analysis of various isotopes in bulk samples. The deuterium-tritium (DT) fusion reaction generates highly penetrating, high-energy (14.1-MeV) neutrons which induce nuclear reactions in irradiated targets. Neutrons and gamma rays are generated in these reactions. Emitted gamma rays are characteristic of the emitter; the gamma spectrum enables stoichiometric identification of the assayed samples. Neutron backscattering can also be used for identification of the elemental composition of the sample.
This work had three objectives. The first objective was to develop a computational technique to model the DT neutron-based assay. The second objective was to examine the in situ fast-neutron assay of Martian and Lunar regoliths for H2O. The third objective was to evaluate the nondestructive DT neutron assay of potentially hazardous compounds for applications in national security and defense. Each assay scenario was modeled using the Monte Carlo N-Particle code (MCNP). The astrochemistry scenarios assumed a potential robotic lander to carry the fast-neutron probe with optimal shielding and moderator components. The security scenario included a dual- mode (gamma rays and neutrons) detector for active interrogation of suspicious samples.
The Monte Carlo modeling data were analyzed using spectral processing routines developed in MATLAB, and subsequent determinations of stoichiometry of the samples and element’s detectability were made. Based on the study, an overall conclusion about the model’s viability for astrochemistry and security applications was made. Potential future work was considered.
Keywords
Astrochemistry; Astrogeology; MCNP; Neutron
Disciplines
Nuclear | Nuclear Engineering
File Format
File Size
1700 KB
Degree Grantor
University of Nevada, Las Vegas
Language
English
Repository Citation
Lane, Calder Emerson, "Fast Neutron Assay of Elemental Content of Bulk Samples" (2020). UNLV Theses, Dissertations, Professional Papers, and Capstones. 4060.
http://dx.doi.org/10.34917/23469731
Rights
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