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Transverse Energy Analysis In Small Collision Systems, Alexander L. Aukerman 2022 University of Tennessee, Knoxville

Transverse Energy Analysis In Small Collision Systems, Alexander L. Aukerman

Masters Theses

Heavy Ion Collisions performed in the LHC at Cern are capable of generating a new phase of nuclear matter known as the Quark Gluon Plasma. In addition to running heavy ion collisions, the detectors dedicated to studying the QGP perform collisions utilizing smaller collision systems for the sake of comparing key measurements associated with the creation of a QGP. The transverse energy of the particles generated from the collision is one such key measurement. For the sake of comparison an analysis is performed on the transverse energy measurements taken from proton-proton collisions.


Extractive Membranes For The Detection And Screening Of Waterborne Plutonium, James Foster 2022 Clemson University

Extractive Membranes For The Detection And Screening Of Waterborne Plutonium, James Foster

All Dissertations

The development of rapid screening tools for special nuclear materials remains a crucial focus for nonproliferation efforts. Traditional approaches for the analysis of trace-level Pu isotopes in water requires tedious and time-consuming sample preparation steps that do not lend well to expeditious screening. Therefore, a novel analytical method that combines both Pu concentration and source preparation into a single detection system would make for an invaluable tool for nuclear security applications. Extractive membranes absorbers can help to fulfill this role as they are capable of concentrating Pu to detectable limits while subsequently serving as alpha spectrometry sample sources. In Chapter …


Enigma - Ongoing Development Towards Novel Beta-Decay Spectroscopy Station At Isolde, Philipp Wagenknecht 2022 University of Tennessee, Knoxville

Enigma - Ongoing Development Towards Novel Beta-Decay Spectroscopy Station At Isolde, Philipp Wagenknecht

Masters Theses

Beta decay and collinear laser spectroscopy are proven efficient tools to study nuclear structure far from stability. Two areas of significance are investigations into nuclear deformation and shape coexistence, as well as delayed neutron emissions used in nuclear energy applications. This contribution presents the ongoing development towards a novel beta-decay spectroscopy station for the VITO experiment at CERN’s radioactive ion beam facility ISOLDE. The setup will utilize both collinear laser spectroscopy and beta-decay spectroscopy to measure the energy and spin-parities of the ground and excited states of radioactive beams. Initial designs of the support structure, magnetic field, and detector array …


Design & Analysis Of Mixed-Mode Integrated Circuit For Pulse-Shape Discrimination, Bryan Orabutt 2022 Washington University in St. Louis

Design & Analysis Of Mixed-Mode Integrated Circuit For Pulse-Shape Discrimination, Bryan Orabutt

McKelvey School of Engineering Theses & Dissertations

In nuclear science experiments it is usually necessary to determine the type of radiation, its energy and direction with considerable accuracy. The detection of neutrons and discriminating them from gamma rays is particularly difficult. A popular method of doing so is to measure characteristics intrinsic to the pulse shape of each radiation type in order to perform pulse-shape discrimination (PSD).

Historically, PSD capable systems have been designed with two approaches in mind: specialized analog circuitry, or digital signal processing (DSP). In this work we propose a PSD capable circuit topology using techniques from both the analog and DSP domains. We …


Study Of One-Nucleon Transfer Reactions, Jerome Mathew Kovoor 2022 University of Tennessee, Knoxville

Study Of One-Nucleon Transfer Reactions, Jerome Mathew Kovoor

Doctoral Dissertations

The structure of nuclei away from the line of stability and near the driplines in the nuclear chart has been of huge interest since the arrival of radioactive ion beam facilities. The properties of nuclei evolve as a function of proton and neutron numbers and understanding the mechanisms behind this is one of the keys to explaining the strong nuclear force. Single-nucleon transfer reactions using deuteron targets are powerful probes of nuclear structure when the emitted proton or neutron is measured with high fidelity.

A variety of structure phenomena are observed in the beryllium isotopes marking them particularly attractive for …


A High Rate Pixelated Neutron Detector For Neutron Reflectometry At The Spallation Neutron Source, Su-Ann Chong 2022 University of Tennessee, Knoxville

A High Rate Pixelated Neutron Detector For Neutron Reflectometry At The Spallation Neutron Source, Su-Ann Chong

Doctoral Dissertations

This work presents the development of a high-rate 6Li-based pixelated neutron detector for neutron reflectometry instruments at the Spallation Neutron Source (SNS), Oak Ridge National Laboratory. The current detector technology falls short on the instrument requirements, particularly on the counting rate capability. This detector was designed specifically to overcome the limitation in counting rate by having a fully pixelated design from neutron conversion layer to photodetector and readout system. For the neutron converting layer, a 6Li-based neutron scintillator was used. Each scintillator element was coupled to a photodetector, in this case, a silicon photomultiplier (SiPM). The output of each SiPM …


Development Of A Prototype Electron Detector For Use In Ucna+, Richard McDonald 2022 East Tennessee State University

Development Of A Prototype Electron Detector For Use In Ucna+, Richard Mcdonald

Undergraduate Honors Theses

The UCNA Experiment at the Los Alamos Neutron Science Center (LANSCE) uses an electron spectrometer to observe angular correlations between the neutron spin and the momenta of β particles emitted during the process of β decay. These angular correlations give rise to an asymmetry determined by the ratio of two coupling constants, gA and gV . Combined with neutron lifetime measurements, these observations probe physics beyond the standard model through unitarity tests of the Cabbibo-Kobayashi-Maskawa Matrix. UCNA’s current spectrometer uses a multi-wire proportional chamber and a plastic scintillator coupled to four photomultiplier tubes (PMTs) by 2 meters of light guides …


Investigating Gluonic Operators In Coordinate Space, Wayne Henry Morris III 2022 Old Dominion University

Investigating Gluonic Operators In Coordinate Space, Wayne Henry Morris Iii

Physics Theses & Dissertations

In this dissertation, a method of extracting gluon momentum distributions inside hadrons, and particularly nucleons, is developed. In general, the utility and application of performing calculations in coordinate space at the operator level is discussed, and its application to the method of pseudodistributions in the lattice extraction of parton distributions. An introduction to the background field method and other techniques used in the calculation of corrections to gluon operators are provided. Then, an outline of the calculation of the uncontracted gluon bilocal operator at one-loop is given, and the result thereof. Using the result for the gluon bilocal operator restricted …


Studies Of Bonus12 Radial Gem Detector And Tcs Beam Spin Asymmetry In Clas12, Jiwan Poudel 2022 Old Dominion University

Studies Of Bonus12 Radial Gem Detector And Tcs Beam Spin Asymmetry In Clas12, Jiwan Poudel

Physics Theses & Dissertations

The Barely Offshell Nucleon Structure (BONuS12) experiment adopted the concept of spectator tagging technique to study the nearly-free neutron structure function F2n in the CLAS12 of Jefferson Lab. A novel Radial Time Projection Chamber (RTPC) detector was built, tested and integrated into the CLAS12 system to detect a back-moving low momentum tagged proton in d(e, ep)X deep-inelastic scattering. It was a 40 cm long gaseous detector consisting of 3 layers of cylindrical GEM foils for the charge amplification, with the data readout directly from the surrounding padboard. The RTPC detected the recoiling spectator proton, in coincidence with …


An Overview Of Approaches To Nuclear Security In Ghana, Raymond Agalga, Paul Atta Amoah, Daniel Nii Adjei, Daniel Frederick Charles, Emmanuel Ofori Darko 2022 Ghana Atomic Energy Commission

An Overview Of Approaches To Nuclear Security In Ghana, Raymond Agalga, Paul Atta Amoah, Daniel Nii Adjei, Daniel Frederick Charles, Emmanuel Ofori Darko

International Journal of Nuclear Security

Ghana has significantly improved its nuclear security infrastructure over the years. However, as threats increase by the day and new applications of nuclear and radiological technology are designed and implemented, Ghana must develop a rigid and comprehensive approach to mitigating the negative impacts on its nuclear security while improving prevention, detection, and deterrence of nuclear and radiological terrorism within its geographical space. This paper overviews the approaches adopted by Ghana to build a strong nuclear security regime within the past decade. These include improving legal frameworks for nuclear security by establishing an independent Nuclear Regulatory Authority; assessing nuclear security culture …


A Machine Learning Approach To Denoising Particle Detector Observations In Nuclear Physics, Polykarpos Thomadakis, Angelos Angelopoulos, Gagik Gavalian, Nikos Chrisochoides 2022 Old Dominion University

A Machine Learning Approach To Denoising Particle Detector Observations In Nuclear Physics, Polykarpos Thomadakis, Angelos Angelopoulos, Gagik Gavalian, Nikos Chrisochoides

College of Sciences Posters

With the evolution in detector technologies and electronic components used in the Nuclear Physics field, experimental setups become larger and more complex. Faster electronics enable particle accelerator experiments to run with higher beam intensity, providing more interactions per time and more particles per interaction. However, the increased beam intensities present a challenge to particle detectors because of the higher amount of noise and uncorrelated signals. Higher noise levels lead to a more challenging particle reconstruction process by increasing the number of combinatorics to analyze and background signals to eliminate. On the other hand, increasing the beam intensity can provide physics …


Energy Analysis For Neutron Induced Ternary Fission Events In The Niffte Fission Time Projection Chamber, Vanessa Aguilar 2022 California Polytechnic State University, San Luis Obispo

Energy Analysis For Neutron Induced Ternary Fission Events In The Niffte Fission Time Projection Chamber, Vanessa Aguilar

Physics

In this paper, energy analyses were made for investigating ternary fission in neutron-induced fission of U235 and U238 using the Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration’s fission time projection chamber (TPC) data. The Neutron kinetic energy was calculated from neutron time of flight (nToF) for energy ranges of 0.1 to 32 MeV. Along with this, the Stopping and Range of Ions in Matter (SRIM) software was used to simulate alphas going through an argon gas target in order to calibrate observed energy loss of alphas from ternary fission.


Partial Muon Capture Rates In A = 3 And A = 6 Nuclei With Chiral Effective Field Theory, G. B. King, S. Pastore, M. Piarulli, Rocco Schiavilla 2022 Washington University in St. Louis

Partial Muon Capture Rates In A = 3 And A = 6 Nuclei With Chiral Effective Field Theory, G. B. King, S. Pastore, M. Piarulli, Rocco Schiavilla

Physics Faculty Publications

Searches for neutrinoless double-β decay rates are crucial in addressing questions within fundamental symmetries and neutrino physics. The rates of these decays depend not only on unknown parameters associated with neutrinos, but also on nuclear properties. In order to reliably extract information about the neutrino, one needs an accurate treatment of the complex many-body dynamics of the nucleus. Neutrinoless double-β decays take place at momentum transfers on the order of 100MeV /c and require both nuclear electroweak vector and axial current matrix elements. Muon capture, a process in the same momentum transfer regime, has readily available experimental data to validate …


Physics-Informed Neural Networks (Pinns) For Dvcs Cross Sections, Manal Almaeen, Jake Grigsby, Joshua Hoskins, Brandon Kriesten, Yaohang Li, Huey-Wen Lin, Simonetta Liuti, Sorawich Maichum 2022 Old Dominion University

Physics-Informed Neural Networks (Pinns) For Dvcs Cross Sections, Manal Almaeen, Jake Grigsby, Joshua Hoskins, Brandon Kriesten, Yaohang Li, Huey-Wen Lin, Simonetta Liuti, Sorawich Maichum

College of Sciences Posters

We present a physics informed deep learning technique for Deeply Virtual Compton Scattering (DVCS) cross sections from an unpolarized proton target using both an unpolarized and polarized electron beam. Training a deep learning model typically requires a large size of data that might not always be available or possible to obtain. Alternatively, a deep learning model can be trained using additional knowledge gained by enforcing some physics constraints such as angular symmetries for better accuracy and generalization. By incorporating physics knowledge to our deep learning model, our framework shows precise predictions on the DVCS cross sections and better extrapolation on …


Using Z Boson Events To Study Parton-Medium Interactions In Pb-Pb Collisions, The CMS Collaboration, A. M. Sirunyan, A. Tumasyan, W. Adam, F. Ambrogi, T. Bergauer, Julie M. Hogan 2022 Yerevan Physics Institute

Using Z Boson Events To Study Parton-Medium Interactions In Pb-Pb Collisions, The Cms Collaboration, A. M. Sirunyan, A. Tumasyan, W. Adam, F. Ambrogi, T. Bergauer, Julie M. Hogan

Physics and Engineering Faculty Publications

The spectra measurements of charged hadrons produced in the shower of a parton originating in the same hard scattering with a leptonically decaying Z boson are reported in lead-lead nuclei (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Both Pb-Pb and pp data sets are recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 1.7 nb-1 and 320 pb-1, respectively. Hadronic collision data with one reconstructed Z boson candidate with the transverse momentum pT>30 GeV/c are analyzed. The Z boson constrains the initial energy and direction of the …


Electron-Positron Annihilation Lifetime Spectroscopy Of Mgo And Aluminum-Doped Mgo, Elise Liebow 2022 Union College - Schenectady, NY

Electron-Positron Annihilation Lifetime Spectroscopy Of Mgo And Aluminum-Doped Mgo, Elise Liebow

Honors Theses

Radiation is a form of energy that can damage materials at an atomic level. This has implications for the mobility of radioactive waste through containment materials. We are characterizing atomic defects in materials by using Electron-Positron Annihilation Lifetime Spectroscopy (EPALS). When an electron and positron come into contact with each other, they annihilate and release two antiparallel 511-keV gamma rays. In a pristine crystalline sample, positrons can easily annihilate with electrons, but in a sample with vacancies/defects in the crystal structure, positrons take longer to annihilate. Therefore, the more vacancies in a sample, the longer the average lifetime of a …


Deformed No-Core Shell Model And Symplectic Effective Field Theory, David Kekejian 2022 Louisiana State University

Deformed No-Core Shell Model And Symplectic Effective Field Theory, David Kekejian

LSU Doctoral Dissertations

Most nuclei are deformed! This simple fact has been established since Bohr and Mot- telson, and successfully demonstrated from first principles by nuclear structure calculations carried out using the ab-initio Symmetry-Adapted No-Core Shell Model (SA-NCSM) us- ing realistic interactions. This simple fact has been the main driver towards understanding the underlying physics; namely, that symplectic symmetry describes deformation and is a dominant symmetry in all nuclei independent of A (nucleon number) and of the realistic interaction used. These two simple observations laid the foundation of this thesis work to explore the applications of symplectic symmetry towards defining a deformed symplectic …


Development Of Advanced Machine Learning Models For Analysis Of Plutonium Surrogate Optical Emission Spectra, Ashwin P. Rao, Phillip R. Jenkins, John D. Auxier II, Michael B. Shattan, Anil Patnaik 2022 Air Force Institute of Technology

Development Of Advanced Machine Learning Models For Analysis Of Plutonium Surrogate Optical Emission Spectra, Ashwin P. Rao, Phillip R. Jenkins, John D. Auxier Ii, Michael B. Shattan, Anil Patnaik

Faculty Publications

This work investigates and applies machine learning paradigms seldom seen in analytical spectroscopy for quantification of gallium in cerium matrices via processing of laser-plasma spectra. Ensemble regressions, support vector machine regressions, Gaussian kernel regressions, and artificial neural network techniques are trained and tested on cerium-gallium pellet spectra. A thorough hyperparameter optimization experiment is conducted initially to determine the best design features for each model. The optimized models are evaluated for sensitivity and precision using the limit of detection (LoD) and root mean-squared error of prediction (RMSEP) metrics, respectively. Gaussian kernel regression yields the superlative predictive model with an RMSEP of …


Development And Characterization Of Germanium Detectors For Searching Rare-Event Physics, Rajendra Panth 2022 University of South Dakota

Development And Characterization Of Germanium Detectors For Searching Rare-Event Physics, Rajendra Panth

Dissertations and Theses

High-purity germanium (HPGe) detector has an excellent energy resolution and low-energy detection threshold ideal for searching rare-event physics such as dark matter and neutrinoless double beta decay searches. Understanding the electrical contact properties and the Ge detector properties is key to enhancing the use of Ge detectors for a wide range of applications. Amorphous Ge (a-Ge) is one of the passivation materials used to passivate Ge detectors, which also provides the barrier height to the charge injection. Several a-Ge contact Ge detectors were fabricated and tested at the University of South Dakota (USD) and Max-Planck-Institut (MPI) für Physik in Munich …


Cosmogenically-Induced Backgrounds In Legend, Clay Douglas Barton 2022 University of South Dakota

Cosmogenically-Induced Backgrounds In Legend, Clay Douglas Barton

Dissertations and Theses

Neutrinoless double-beta decay (0νββ) is a hypothetical nuclear decay mode. 0νββ searches are a high priority in nuclear physics. Discovery would ascertain the nature of the neutrino as the first known fundamental Majorana particle, and have far-reaching implications for physics beyond the Standard Model, including a lower bound on the effective neutrino mass scale, first direct evidence of a lepton number violating process, and insight into the matter-antimatter asymmetry in the universe. The next-generation LEGEND (Large Enriched Germanium Experiment for Neutrinoless ββ Decay) project will search for neutrinoless double-beta decay of 76Ge. LEGEND builds on infrastructure and technical expertise of …


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