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Articles 1 - 30 of 179
Full-Text Articles in Nuclear Engineering
Impact Of Collodion Thickness On Fission Track Generation Within Lexan Employed For Nuclear Forensic Analyses, Ryan K. Chapman, Zachary P. Meisel, Abigail A. Bickley
Impact Of Collodion Thickness On Fission Track Generation Within Lexan Employed For Nuclear Forensic Analyses, Ryan K. Chapman, Zachary P. Meisel, Abigail A. Bickley
Faculty Publications
We report results from a computational study of fission track damage within a Lexan substrate caused by 235U suspended within a collodion film of varied thickness. MCNP6.3 was used to model energy deposition and displacements per atom within a Lexan film coated by a film of collodion, located within the air-filled 6 inch dry tube of a TRIGA reactor. The collodion layer was varied between 20 and 100 μm thickness, resulting in an 8.8% difference in energy deposition and 12% difference in displacements-per-atom within the Lexan substrate. These findings indicate that collodion adhesive thickness has a moderate impact on …
Radiation Protection Factor Research: The Keystone For Conventional-Nuclear Integration (Cni), Andrew W. Decker
Radiation Protection Factor Research: The Keystone For Conventional-Nuclear Integration (Cni), Andrew W. Decker
Faculty Publications
This article briefly describes Defense Threat Reduction Agency (DTRA) vehicle Radiation Protection Factor (RPF) research and explains its critical role in enabling future Operations in a Nuclear Environment (ONE) and Conventional-Nuclear Integration (CNI) on behalf of the US Department of War (DoW).1 As such, the background and practical utility of RPF values is discussed, as well as the justification for renewed Army and DoW investment into RPF research to enhance Joint military planning, survivability, and lethality on tomorrow’s nuclear battlefields. Advances in DTRA RPF research directly strengthen US strategic and extended deterrence efforts and support all Agencies and Departments responsible …
Investigating The Impact Of Forest Vegetation On Nuclear Weapon Prompt Radiation Energy Deposition, Paul A. Clement
Investigating The Impact Of Forest Vegetation On Nuclear Weapon Prompt Radiation Energy Deposition, Paul A. Clement
Theses and Dissertations
This work seeks to answer the unstudied questions “Does a layer of vegetation impact the prompt radiation energy deposition in the soil from an atmospheric nuclear detonation?” and “If yes, by how much?” A new methodology was developed to repeatably automate and streamline a process of generating a three-dimensional geometry for subsequent radiation transport simulations and statistical analysis. The methodology streamlined three diverse applications: a three-dimensional mesh generator, a radiation transport simulation code, and a sensitivity analysis & uncertainty quantification software. The methodology was tested by simulating the quantitative influence that vegetation has on changing the energy deposition into the …
Isotope Production Modeling In Sodium-Cooled Fast Reactors, Aaron W. Burkhardt
Isotope Production Modeling In Sodium-Cooled Fast Reactors, Aaron W. Burkhardt
Theses and Dissertations
The accurate prediction of isotopic compositions in Sodium-Cooled Fast Reactors (SFRs) is essential for nuclear forensic analyses and international nuclear treaty monitoring, particularly with the increased global deployment of Generation-IV reactors. This research developed and validated a detailed computational model tailored specifically to the Prototype Fast Breeder Reactor (PFBR), employing advanced Monte Carlo neutron transport methods, sophisticated burnup modeling, and variance reduction techniques. Validation against empirical data from the Experimental Breeder Reactor-II confirmed the model’s accuracy, producing a comprehensive database of isotopic compositions across 301 assembly locations and 580 isotopes through the reactor’s initial operation and equilibrium cycle. The model …
Constraining Nuclear Data Uncertainty Requirements For The 19F(A, N)22Na Reaction For Non-Proliferation Applications, Tyler R. M. Smith
Constraining Nuclear Data Uncertainty Requirements For The 19F(A, N)22Na Reaction For Non-Proliferation Applications, Tyler R. M. Smith
Theses and Dissertations
This thesis explores the requirements on nuclear data uncertainties needed for the use of the 19F(α, n)22Na reaction for nuclear non-proliferation applications. An overview of how neutrons are produced from alpha decays in a UF6 medium is discussed. Calculation demonstrate the role nuclear data uncertainties effect the neutron yield and energy spectra as a function of enrichment.
The Effects Of Snow Cover On The Dynamic Pressure Of Nuclear Detonation Blast Waves, Adam Card, Andrew W. Decker
The Effects Of Snow Cover On The Dynamic Pressure Of Nuclear Detonation Blast Waves, Adam Card, Andrew W. Decker
Faculty Publications
Blast pressure is the primary military targeting metric for nuclear weapons. Any local conditions that affect blast pressure have the potential for altering nuclear plans, both from defensive and offensive standpoints. Understanding the impact of snow to the blast wave, therefore, provides a benefit both to military planners and to warfighters on the ground, for any operation occurring in arctic environments. No existing data provides a quantitative description of how snow on the ground affects a nuclear detonation blast wave passing over it. Similar blast waves passing over dust have experimentally proven to enhance blast pressure in a localized region.1 …
Machine Learning For Reactor Power Monitoring With Limited Labeled Data, C. L. Stewart, B. L. Goldblum, R. G. Abbott, L. Appleby, Brett J. Borghetti, V. Hollingshead, J. H. Whetzel
Machine Learning For Reactor Power Monitoring With Limited Labeled Data, C. L. Stewart, B. L. Goldblum, R. G. Abbott, L. Appleby, Brett J. Borghetti, V. Hollingshead, J. H. Whetzel
Faculty Publications
Real-time reactor power monitoring is critical for a variety of nuclear applications, spanning safety, security, operations, and maintenance. While machine learning methods have shown promise in monitoring reactor power levels, there is limited research on their efficacy in label-starved environments. The goal of this work is to assess the feasibility of classifying nuclear reactor power level using multisource data in scenarios with limited labels. Data were collected using low-resolution multisensors at four nuclear reactor facilities: two large research reactors and two TRIGA reactors. Within each pair, one reactor dataset served as the source and the other as the target in …
Radiation Assessment And Distribution In Changing Atmospheric Structures And Turbulence (Radcast), Steven B. Hernandez
Radiation Assessment And Distribution In Changing Atmospheric Structures And Turbulence (Radcast), Steven B. Hernandez
Theses and Dissertations
The accessibility of materials and online information has made radiological dispersal devices (RDDs) a more probable threat than conventional nuclear weapons. This study analyzed five datasets from three test periods, using a correlation analysis between optical turbulence, aerosol concentration, and environmental parameters, and geometric mean diameter (GMD) calculations. The correlation analysis failed to yield meaningful insights, prompted a transition to the GMD analysis, which produced clearer results. Findings show GMD ranged from 38–41 nm, increasing at night and during neutral events as reduced vertical motion and boundary layer contraction correlated with optical turbulence. An alternative GMD dataset, calculated by the …
Measurements Of The Radioisotope Production Cross Section Of 193Ir(N,N')193mIr Between 0.5–9 Mev, Ronnie P. Rera
Measurements Of The Radioisotope Production Cross Section Of 193Ir(N,N')193mIr Between 0.5–9 Mev, Ronnie P. Rera
Theses and Dissertations
This thesis covers a measurements of the radioisotope production cross section of 193Ir(n,n′) 193mIr between 0.5–9 MeV is discussed. The experiment was performed at the University of Notre Dame St.ANA 5U accelerator laboratory. Experimental planning, data collection, analysis, results, and impacts are discussed.
Characterization Of The Neutron Spectrum Produced By A Pulsed Power Generator, Daniel S. Godlasky
Characterization Of The Neutron Spectrum Produced By A Pulsed Power Generator, Daniel S. Godlasky
Theses and Dissertations
Neutron time-of-flight, activation foils, and spectral unfolding software were used to characterize the energy and fluence of the neutron spectrum created by the Gamble II pulsed power generator. Gamble II is a pulsed power generator that delivers a 1 MV to 2.2 MV and 800 kA electrical pulse peaking at 50 ns. This electrical release creates deuterium ions in the diode that are accelerated to a neutron converter covered with a novel lithium fluoride or deuterated polyethylene to create primarily 7Li(d,n) or D(d,n) and 12C(d,n) nuclear reactions. In October 2024, two D(d,n) shots occurred, and in November 2024, …
Design, Simulation, And Characterization Of A Deuterated Plastic Scintillator For A Portable Neutron Spectrometer, Anders M. Kinney Ii
Design, Simulation, And Characterization Of A Deuterated Plastic Scintillator For A Portable Neutron Spectrometer, Anders M. Kinney Ii
Theses and Dissertations
This thesis examines the design, simulation, and experimental characterization of a novel deuterated plastic scintillator for portable neutron spectroscopy applications related to homeland security and nuclear non-proliferation. Using Monte Carlo N-Particle (MCNP) simulations and experimental tests with gamma-ray (137Cs) and neutron sources (AmBe, 252Cf), this research shows that deuterium substitution in scintillators significantly enhances pulse shape discrimination (PSD) and neutron energy spectrum unfolding capabilities. Although deuterated scintillators demonstrate reduced overall light output, their higher stopping power and increased ionization quenching lead to superior neutron event differentiation, particularly between (α, n) and spontaneous fission neutrons critical for detecting …
The Evaluation Of Machine Learning Techniques For Isotope Identification Contextualized By Training And Testing Spectral Similarity, Aaron P. Fjelsted, Tyler J. Morrow, Clayton D. Scott, Yilun Zhu, Darren E. Holland, Azaree T. Lintereur, Douglas E. Wolfe
The Evaluation Of Machine Learning Techniques For Isotope Identification Contextualized By Training And Testing Spectral Similarity, Aaron P. Fjelsted, Tyler J. Morrow, Clayton D. Scott, Yilun Zhu, Darren E. Holland, Azaree T. Lintereur, Douglas E. Wolfe
Faculty Publications
Precise gamma-ray spectral analysis is crucial in high-stakes applications, such as nuclear security. Research efforts toward implementing machine learning (ML) approaches for accurate analysis are limited by the resemblance of the training data to the testing scenarios. The underlying spectral shape of synthetic data may not perfectly reflect measured configurations, and measurement campaigns may be limited by resource constraints. Consequently, ML algorithms for isotope identification must maintain accurate classification performance under domain shifts between the training and testing data. To this end, four different classifiers (Ridge, Random Forest, Extreme Gradient Boosting, and Multilayer Perceptron) were trained on the same dataset …
Generation And Implementation Of Mixed Radiation From Laser Interactions On A Liquid Target, Benjamin M. Knight
Generation And Implementation Of Mixed Radiation From Laser Interactions On A Liquid Target, Benjamin M. Knight
Theses and Dissertations
The simultaneous generation of different forms of radiation from the same source is highly desirable but technically challenging. We present the generation of D-D fusion neutrons and >MeV-energy x-rays from extreme intensity (∼ 1019 W/cm2 ), high repetition-rate (1 kHz) laser pulses on a thin liquid target. Total neutron fluxes of ∼ 105 neutrons/s and x-ray exposure rates up to ∼ 200 R/hr at 74 cm are measured. Evidence of D-D fusion is verified with a measurement suite including three independent neutron detection systems: an EJ-309 organic scintillator, a 3He proportional counter, and a set of 36 …
Pulsed-Power Neutron Production With Deuterated Polymer Accelerator Targets, Anthony O. Hagey, Juan J. Manfredi, Whitman T. Dailey, S. L. Jackson, E. R. Kaiser, J, W. Schumer
Pulsed-Power Neutron Production With Deuterated Polymer Accelerator Targets, Anthony O. Hagey, Juan J. Manfredi, Whitman T. Dailey, S. L. Jackson, E. R. Kaiser, J, W. Schumer
Faculty Publications
This document presents an investigation of the effect of deuterated accelerator targets on the neutron fluence from a local mass injection dense plasma focus (LMIDPF) driven by the United States Naval Research Laboratory's (NRL) Hawk pulsed-power generator. Deuterated targets were made using two methods: a well-established thin-film casting technique for flat targets and a more novel additive manufacturing technique that allowed targets to be three-dimensional (3D) printed in both flat and conical geometries. These targets were then tested during neutron-producing experiments conducted using Hawk, and theneutron fluences measured for the various target types were compared. Additive manufacturing was used as …
Synergistic Effects Of Neutron And Gamma Radiations On The Electrical Properties Of Mosfets, Jackson T. Piechowski
Synergistic Effects Of Neutron And Gamma Radiations On The Electrical Properties Of Mosfets, Jackson T. Piechowski
Theses and Dissertations
In many radiation environments, electronic assets are exposed to a wide variety of species of radiation. This thesis studies the effect of sequential exposure of MOSFETs to neutron and gamma radiation. 27 Goford Semiconductor GT060N04T MOSFETs with gate thickness ∼500 nm were exposed to gamma radiation from a Cesium-137 source and mixed gamma and neutron radiation from a Californium-252 source with total amounts of ionizing radiation dose, neutron fluence, and order of irradiation varied to determine if synergistic effects of neutron and gamma irradiation can be measured. Neutron fluence values as low as 3.45x109 and as high as 3.40x10 …
Neutron Spectrum Unfolding From Activation Foils Irradiated In Gamble Ii Using Deuterated Polyethylene Anodes, Christopher J. Smith
Neutron Spectrum Unfolding From Activation Foils Irradiated In Gamble Ii Using Deuterated Polyethylene Anodes, Christopher J. Smith
Theses and Dissertations
Neutrons can cause irreparable harm to electronics, and experiments are needed to understand their effects fully. This work explores using pulsed power, which is low-cost compared to other sources, to create a useful neutron-rich environment. Deuterated polyethylene was used as anode and catcher material to generate the neutrons from the Deuterium-Deuterium (DD) fusion reaction. A simple, effective, and repeatable method was employed to directly cast deuterated polyethylene onto polyethylene sheets to fabricate the anode and catcher. The DD reactions were made by an ion beam-driven pulsed power generator, Gamble II, with the catcher located in the cathode. Zinc, copper, aluminum, …
Gamma Protection Factor For A Surrogate Armored Vehicle Exposed To The Us Army Fast Burst Reactor, Ian J. Poropat
Gamma Protection Factor For A Surrogate Armored Vehicle Exposed To The Us Army Fast Burst Reactor, Ian J. Poropat
Theses and Dissertations
This work measures the Gamma Protection Factor (GPF) of a steel cube, which is meant to serve as a surrogate for armored vehicles. The GPF is measured at the White Sands Missile Range Fast Burst Reactor (FBR) and is modeled using MCNP® v6.2 transport simulation software. When exposed to the FBR, the GPF is found to depend roughly linearly on the distance between the reactor core and steel cube. The GPF is determined to be 1.176 ± 0.00067 at 9.21 m, 1.098 ± 0.0011 at 26.16 m, and 1.033 ± 0.00082 at 42.92 m. MCNP® estimates the GPF for the …
Personal Dosimeter Testing For High Altitude Air Crew, Seth D. Bacon
Personal Dosimeter Testing For High Altitude Air Crew, Seth D. Bacon
Theses and Dissertations
In 2014 the Thermo Scientific N2 electronic personal dosimeter became the aircrews’ sole means to record ionizing radiation dose. The production of this dosimeter was discontinued in July of 2021, motivating the Air Force to seek a flight-certifiable replacement. The Thermo Scientific Trudose NG, Mirion DMC 3000, and Fuji NRF-51 electronic personal dosimeters, as well as the Landauer InLight optically stimulated luminescent dosimeter, were subjected to mixed gamma and fast neutron fields simulating a high-altitude flight environment. Dosimeters are evaluated on their consistency and accuracy in reporting dose and compared to the current N2 dosimeter’s reported dose.
Measuring Radiation Protection: Partners From Across The Nuclear Enterprise Evaluate The Radiation Protection Of Us Army Vehicles, Andrew W. Decker, Robert Prins
Measuring Radiation Protection: Partners From Across The Nuclear Enterprise Evaluate The Radiation Protection Of Us Army Vehicles, Andrew W. Decker, Robert Prins
Faculty Publications
Recent mounting nuclear threats and postures from adversary nation-states, such as Russia, China, North Korea, and Iran, represent a clear danger to the interests and security of the United States of America and its Allies. To meet these threats, the 2022 Nuclear Posture Review requires the Department of Defense (DoD) to design, develop, and manage a combat-credible U.S. military which, among other prioritizations, is survivable. A survivable force can generate combat power despite adversary attacks. As such, the US Army must prepare today to set the conditions for successful conventional warfare on the nuclear battlefields of tomorrow. Our Army cannot …
Fast-, Light-Cured Scintillating Plastic For 3d-Printing Applications, Brian G. Frandsen, Michael Febbraro, Thomas Ruland, Theodore W. Stephens, Paul A. Hausladen, Juan J. Manfredi, James E. Bevins
Fast-, Light-Cured Scintillating Plastic For 3d-Printing Applications, Brian G. Frandsen, Michael Febbraro, Thomas Ruland, Theodore W. Stephens, Paul A. Hausladen, Juan J. Manfredi, James E. Bevins
Faculty Publications
Additive manufacturing techniques enable a wide range of possibilities for novel radiation detectors spanning simple to highly complex geometries, multi-material composites, and metamaterials that are either impossible or cost prohibitive to produce using conventional methods. The present work identifies a set of promising formulations of photocurable scintillator resins capable of neutron-gamma pulse shape discrimination (PSD) to support the additive manufacturing of fast neutron detectors. The development of these resins utilizes a step-by-step, trial-and-error approach to identify different monomer and cross-linker combinations that meet the requirements for 3D printing followed by a 2-level factorial parameter study to optimize the radiation detection …
Automated Additive Layering Of Vat Polymerized Plastic Organic Scintillators, Chandler J. Moore
Automated Additive Layering Of Vat Polymerized Plastic Organic Scintillators, Chandler J. Moore
Theses and Dissertations
The current technology for fast neutron detection imaging is limited in achieving the required high spatial resolution, strong neutron discrimination, and practical time of manufacturing. Traditional fabrication methods require days of thermal polymerization and hundreds of man-hours to produce average resolution pixelated scintillator arrays. The present work helps to eliminate this limitation by developing an additive manufacturing technique to construct such detectors for use in in dual particle imaging applications. In this work, fast-, light-curing resins are used in a prototype automated assembly machine, capable of layering of individual light-cured resin layers and optical segmentation with a self-bonded specular reflector, …
Angle Resolved Photoelectron Spectroscopy Study Of Germanium Tin: Experimentally Determined Electronic Band Gap And Surface Analysis, Jeremy M. Hunter
Angle Resolved Photoelectron Spectroscopy Study Of Germanium Tin: Experimentally Determined Electronic Band Gap And Surface Analysis, Jeremy M. Hunter
Theses and Dissertations
The germanium tin band gap is responsive to wavelengths in the mid to near infrared spectrum; this shows promise in meeting the detection demands of the next generation infrared detectors. Recent developments in germanium tin (GeSn) alloy growth techniques have peaked the scientific community’s interest in GeSn based optoelectrical and detection devices. Detection materials made entirely of group IV elements are compatible with complementary metal-oxide semiconductor manufacturing techniques. Understanding the surface chemistry of this alloy is fundamental for solid state device design and must be analyzed to optimize device performance. Studies have shown that with the addition of tin, the …
Fast Engineering Model For Defect Production In Magnesium Oxide, Henry R. Little
Fast Engineering Model For Defect Production In Magnesium Oxide, Henry R. Little
Theses and Dissertations
Defect production from irradiation of materials with thicknesses much less than the mean free path for neutron interaction is explored. A model is developed using the Monte Carlo N-Particle transport code from Los Alamos National Laboratory, experimental data from irradiations at the Oak Ridge High Flux Isotope Reactor, defect production theory, and atomistic simulation results to predict the total number of F-centers resulting from neutron irradiation of a MgO rod. This model accurately predicts the concentration of atomic defects under conditions closely matching experiments at long timescales, for large geometries, and requiring only 6.9 minutes on a single CPU. Results …
Fabrication And Testing Of A Novel Layered Metascintillator For Neutron And Gamma Discrimination, Evan W. Threlkeld
Fabrication And Testing Of A Novel Layered Metascintillator For Neutron And Gamma Discrimination, Evan W. Threlkeld
Theses and Dissertations
By leveraging new developments in fast-curing of plastic scintillators, it is possible to fabricate multi-material plastic scintillators, or metascintillators, which offer improved and/or novel capabilities for radiation detection. This document proposes one geometry of metascintillator that uses layers of green and blue scintillating material to discriminate neutron/gamma radiation, details the devices necessary to fabricate it, and analyzes the metascintillator’s response to radiation. A model of the metascintillator using Geant4 and Python suggested that spectral-based neutron/gamma event discrimination is possible with 63% of gamma events and only 1% of neutron events being multi-color. Fabrication of a 500 µm per layer metascintillator …
Exploring Variations In Fast Curing Plastic Scintillator Formulations: Optimizing Tpo And Evaluating The Effects Of High-Z Loading And Novel Waveshifters, Andrew K. Nesbitt
Exploring Variations In Fast Curing Plastic Scintillator Formulations: Optimizing Tpo And Evaluating The Effects Of High-Z Loading And Novel Waveshifters, Andrew K. Nesbitt
Theses and Dissertations
Organic plastic scintillators are widely used due to their relative low cost, physical robustness, and fast timing properties, but typically provide lower light yields and photon sensitivity compared to other alternatives. Photocuring novel plastics offers a viable method for producing fast curing plastic scintillators. The current formulations include an acrylic polymer base and utilize diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO) as the photo-initiator for polymerization; however at higher concentrations of TPO may adversely affect scintillator light output. The present research refined the optimal TPO concentrations that fully cure these acrylic-base scintillators and maximize light production to 0.4-0.5% by weight. Additionally, this …
Simulation Of Neutron Generation From Laser-Driven Fusion In A Liquid D2o Sheet Using Novel Warpx Module, Colton R. Stoner
Simulation Of Neutron Generation From Laser-Driven Fusion In A Liquid D2o Sheet Using Novel Warpx Module, Colton R. Stoner
Theses and Dissertations
Using WarpX’s new nuclear fusion module, this work attempts to model an experimental system at the ELL at the AFIT with WarpX and draw conclusions about fusion products from resulting simulations. Recently, a table-top, high repetition rate, mixed radiation source was demonstrated at the ELL employing a HIL to fuse the deuterium nuclei present in a unique liquid target of heavy water. Analysis of the simulations predicted an isotropic output of neutrons from deuterium-deuterium fusion. These simulated neutrons were created in tens of femtoseconds from dense bodies of deuterons that were perturbed by the laser. However, it was found that …
Pulsed Power Neutron Production With Deuterated Polymer Accelerator Targets, Anthony O. Hagey
Pulsed Power Neutron Production With Deuterated Polymer Accelerator Targets, Anthony O. Hagey
Theses and Dissertations
This document presents an investigation of the effect of deuterated polyethylene accelerator targets on the neutron fluence from a local mass injection dense plasma focus driven by the United States Naval Research Laboratory’s Hawk pulsed-power generator. After successful production of thin targets, the acquisition of thicker targets, and testing inside Hawk, it was found that the presence of a deuterated polyethylene target increased the neutron fluence. Results suggested that fluence can significantly increase with the presence of a deuterated target vs a nondeuterated target. Additive manufacturing printing was used as a production method in order to determine if deuterated accelerator …
Assessment Of Emergency Cooling Requirement For Nuclear Reactor Loss-Of-Coolant Accidents, Michael T. Lindsay
Assessment Of Emergency Cooling Requirement For Nuclear Reactor Loss-Of-Coolant Accidents, Michael T. Lindsay
Theses and Dissertations
The 2022 Russia-Ukraine War marks the first time in modern history of conventional military forces targeting and seizing control of an operational nuclear power plant. Power supply and operational cooling systems are critical to avert reactor loss-of-coolant accidents (LOCA) in the event of emergency shutdown, or SCRAM. A wartime non-design based reactor accident causing loss of reactor power and coolant supply would require an emergency heat exchange via coolant to mitigate reactor core heat. At present, the military does not have a well-defined model which characterizes this requirement for operational planning should such an event occur. SCALE 6.2.4 is used …
Data Augmentation For Neutron Spectrum Unfolding With Neural Networks, James Mcgreivy, Juan J. Manfredi, Daniel Siefman
Data Augmentation For Neutron Spectrum Unfolding With Neural Networks, James Mcgreivy, Juan J. Manfredi, Daniel Siefman
Faculty Publications
Neural networks require a large quantity of training spectra and detector responses in order to learn to solve the inverse problem of neutron spectrum unfolding. In addition, due to the under-determined nature of unfolding, non-physical spectra which would not be encountered in usage should not be included in the training set. While physically realistic training spectra are commonly determined experimentally or generated through Monte Carlo simulation, this can become prohibitively expensive when considering the quantity of spectra needed to effectively train an unfolding network. In this paper, we present three algorithms for the generation of large quantities of realistic and …
Enabling Rapid Chemical Analysis Of Plutonium Alloys Via Machine Learning-Enhanced Atomic Spectroscopy Techniques, Ashwin P. Rao
Enabling Rapid Chemical Analysis Of Plutonium Alloys Via Machine Learning-Enhanced Atomic Spectroscopy Techniques, Ashwin P. Rao
Theses and Dissertations
Analytical atomic spectroscopy methods have the potential to provide solutions for rapid, high fidelity chemical analysis of plutonium alloys. Implementing these methods with advanced analytical techniques can help reduce the chemical analysis time needed for plutonium pit production, directly enabling the 80 pit-per-year by 2030 manufacturing goal outlined in the 2018 Nuclear Posture Review. Two commercial, handheld elemental analyzers were validated for potential in situ analysis of Pu. A handheld XRF device was able to detect gallium in a Pu surrogate matrix with a detection limit of 0.002 wt% and a mean error of 8%. A handheld LIBS device was …