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Relativistic And Non-Relativistic Proton-Nucleus Scattering, Kinsey Ann Elisabeth Zarske-Williamson 2015 The University of Southern Mississippi

Relativistic And Non-Relativistic Proton-Nucleus Scattering, Kinsey Ann Elisabeth Zarske-Williamson

Honors Theses

Calculations for proton-nucleus scattering often rely on transition amplitudes. We implement new transition amplitudes [7] with the relativistic equations. We can find the matrix elements of the operators between the usual Dirac spinor basis or the helicity spinor basis. The operators can also be written as a linear combination of non-relativistic spin operators. To transform from one basis to another, we need to find a transformation matrix. We must establish what one of the factors that appears in the transformed expression means in order to correctly complete our transformation matrix. Once this is resolved, our transformation matrix will be complete.


Event Localization In Bulk Scintillator Crystals Using Optical Coded Apertures, Joshua Brian Braverman 2015 University of Tennessee - Knoxville

Event Localization In Bulk Scintillator Crystals Using Optical Coded Apertures, Joshua Brian Braverman

Doctoral Dissertations

Scintillation-based radiation detectors provide an effective method to detect radioactive materials. In medical physics, astrophysics, and national security technology oftentimes it is optimal to have the ability to localize a radioactive interaction in a scintillator to as small a region as possible within the crystal. Current methods rely on the ability to centroid a light spot as read onto a phototransducer (commonly a photomultiplier tube), and due to the typical width of the light spot when it reaches the phototransducer, the resolution is generally limited to several millimeters. One method to achieve a finer resolution is to use a segmented ...


Computational Framework For Small Animal Spect Imaging: Simulation And Reconstruction, Sang Hyeb Lee 2015 University of Tennessee - Knoxville

Computational Framework For Small Animal Spect Imaging: Simulation And Reconstruction, Sang Hyeb Lee

Doctoral Dissertations

Small animal Single Photon Emission Computed Tomography (SPECT) has been an invaluable asset in biomedical science since this non-invasive imaging technique allows the longitudinal studies of animal models of human diseases. However, the image degradation caused by non-stationary collimator-detector response and single photon emitting nature of SPECT makes it difficult to provide a quantitative measure of 3D radio-pharmaceutical distribution inside the patient. Moreover, this problem exacerbates when an intra-peritoneal X-ray contrast agent is injected into a mouse for low-energy radiotracers.

In this dissertation, we design and develop a complete computational framework for the entire SPECT scan procedure from the radio-pharmaceutical ...


Mass Table Calculations With Nuclear Density Functional Theory, Noah Watson Birge 2015 University of Tennessee - Knoxville

Mass Table Calculations With Nuclear Density Functional Theory, Noah Watson Birge

Masters Theses

To better understand nuclei and the strong nuclear force, it is useful to analyze global nuclear properties and trends across the nuclear chart. To this end, we utilized Nuclear Density Functional Theory with Skyrme Energy Density Functionals in conjunction with high-performance computing to perform large-scale mass table calculations for even-even nuclei. Using the binding energy, pairing gap, root-mean-square radius, and deformation data from these tables we were able to analyze the two-proton and two-neutron drip lines, neutron skin depth, two-proton radioactivity, and the effect of nuclear deformation on mass filters. We used numerous energy density functionals to assess the statistical ...


Fission Fragment Tracking And Identification In The Neutron-Induced Fission Fragment Tracking Experiment’S Time Projection Chamber, Eric Song 2015 California Polytechnic State University - San Luis Obispo

Fission Fragment Tracking And Identification In The Neutron-Induced Fission Fragment Tracking Experiment’S Time Projection Chamber, Eric Song

Physics

The Neutron-Induced Fission Fragment Tracking Experiment (NIFFTE) built a novel Time Projection Chamber (TPC), the FissionTPC, for measuring neutron-induced fission cross-sections to unprecedented precision. We investigated data from a 2014 run (400010151) at the Los Alamos Neutron Science Center (LANSCE) with a double-sided U235/Pu239 target. Our particle identification studies will aid in the development of improved tracking algorithms.


A Measurement Of The Prompt Fission Neutron Energy Spectrum For 235U(N,F) And The Neutron-Induced Fission Cross Section For 238U(N,F), Zachariah W. Miller 2015 University of Kentucky

A Measurement Of The Prompt Fission Neutron Energy Spectrum For 235U(N,F) And The Neutron-Induced Fission Cross Section For 238U(N,F), Zachariah W. Miller

Theses and Dissertations--Physics and Astronomy

Two measurements have been made, addressing gaps in knowledge for 235U(n,f) and 238U(n,f). The energy distribution for prompt fission neutrons is not well-understood below 1 MeV in 235U(n,f). To measure the 235U(n,f) prompt fission neutron distribution, a pulsed neutron beam at the WNR facility in Los Alamos National Laboratory was directed onto a 235U target with neutron detectors placed 1 m from the target. These neutron detectors were designed specifically for this experiment and employed a unique geometry of scintillating plastic material that was designed to reject ...


Measurement Of The Dμd Quartet-To-Doublet Molecular Formation Rate Ratio (Λq : Λd) And The Μd Hyperfine Rate (Λqd) Using The Fusion Neutrons From Μ− Stops In D2 Gas, Nandita Raha 2015 University of Kentucky

Measurement Of The Dμd Quartet-To-Doublet Molecular Formation Rate Ratio (Λq : Λd) And The Μd Hyperfine Rate (Λqd) Using The Fusion Neutrons From Μ− Stops In D2 Gas, Nandita Raha

Theses and Dissertations--Physics and Astronomy

The MuSun experiment will determine the μd capture rate (μ−+d ->n+n+νe) from the doublet hyperfine state Λd, of the muonic deuterium atom in the 1S ground state to a precision of 1.5%. Modern effective field theories (EFT) predict that an accurate measurement of Λd would determine the two-nucleon weak axial current. This will help in understanding all weak nuclear interactions such as the stellar thermonuclear proton-proton fusion reactions, the neutrino reaction ν+d (which explores the solar neutrino oscillation problem). It will also help us understand weak nuclear interactions involving more than two ...


Design And Model Of The Frame For Hagrid (Hybrid Array Of Gamma Ray Detectors), Santiago Munoz 2014 University of Tennessee - Knoxville

Design And Model Of The Frame For Hagrid (Hybrid Array Of Gamma Ray Detectors), Santiago Munoz

Masters Theses

Transfer reactions in inverse kinematics have provided critical information in the study of exotic nuclei. However, transfer reactions with charged particles suffer from poor resolution. The measurement of gamma-rays offers several advantages: they provide not only good resolution in measurements but also other information about the nuclei like lifetimes of unstable states. The combination of these two methods would be the ideal situation to gather information about nuclear structure.

HAGRiD, which stands for The Hybrid Array of Gamma Ray Detectors, is a LaBr3(Ce) [lanthanum bromide crystal with a cerium activator] scintillation array to measure gamma rays from transfer reactions ...


Mcdaniel, Paul William, 1916-2004 (Mss 515), Manuscripts & Folklife Archives 2014 Western Kentucky University

Mcdaniel, Paul William, 1916-2004 (Mss 515), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid only for Manuscripts Collection 515. Writings and awards of Paul William McDaniel, nuclear physicist and graduate of Western Kentucky University. Includes typescripts of lectures delivered at Queensland University, a journal he kept while serving in World War II, and a copy of his Arthur F. Fleming Award. Also includes many letters of congratulations to him and a copy of the Atomic Energy Act of 1946.


Doube-Pulse Laser-Induced Breakdown Spectroscopy Of Multi-Element Sample Containing Low- And High-Z Analytes, Patrick J. Skrodzki, Jason R. Becker, Prasoon K. Diwakar Ph. D., Sivanandan S. Harilal Ph. D., Ahmed Hassanein Ph. D. 2014 Purdue University

Doube-Pulse Laser-Induced Breakdown Spectroscopy Of Multi-Element Sample Containing Low- And High-Z Analytes, Patrick J. Skrodzki, Jason R. Becker, Prasoon K. Diwakar Ph. D., Sivanandan S. Harilal Ph. D., Ahmed Hassanein Ph. D.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Laser-induced breakdown spectroscopy (LIBS) is a portable, remote, non-invasive analytical technique which effectively distinguishes neutral and ionic species for a range of low- to high-Z elements in a multi-element target. Subsequently, LIBS holds potential in special nuclear material (SNM) sensing and nuclear forensics requiring minimal sample preparation and detecting isotopic shifts which allows for differentiation in SNM (namely U) enrichment levels. Feasible applications include not only nonproliferation and homeland security but also nuclear fuel prospecting and industrial safeguard endorsement. Elements of higher mass with complex atomic structures, such as U, however, result in crowded emission spectra with LIBS, and characteristic ...


Double-Pulse Nd:Yag-Co2 Libs Excitation For Bulk And Trace Analytes, Jason R. Becker, Patrick Skrodzki, Prasoon Diwakar, Sivanandan Harilal, Ahmed Hassanein 2014 Purdue University

Double-Pulse Nd:Yag-Co2 Libs Excitation For Bulk And Trace Analytes, Jason R. Becker, Patrick Skrodzki, Prasoon Diwakar, Sivanandan Harilal, Ahmed Hassanein

The Summer Undergraduate Research Fellowship (SURF) Symposium

Laser-induced breakdown spectroscopy [LIBS] is a commonly used technique for multi-element analyses for various applications such as space exploration, nuclear forensics, environmental analysis, process monitoring. The advantages of the LIBS technique include robustness, ease of use, field portability, and real-time, non-invasive multi-element analyses. However, in comparison to other lab based analytical techniques, it suffers from low precision and low sensitivity. In order to overcome these drawbacks, various approaches have been used, including double-pulse LIBS [DPLIBS]. Typically, various wavelength combinations of two Nd: yttrium aluminum garnet [YAG] lasers have been used for DPLIBS. However, the use of long wavelength (CO2 ...


Characterizing New Calibration Sources In Liquid Xenon Dark Matter Searches, Evan P. Bray, Rafael Lang, Sean MacMullin 2014 Purdue University

Characterizing New Calibration Sources In Liquid Xenon Dark Matter Searches, Evan P. Bray, Rafael Lang, Sean Macmullin

The Summer Undergraduate Research Fellowship (SURF) Symposium

In order to use the XENON1T liquid xenon detector as a means for detecting dark matter, the response to nuclear and electronic recoils must be well calibrated. Electronic-recoil calibration of XENON1T will be done by using the noble gas radon-220 that emanates from a custom thorium-228 source to observe the electron recoils that its daughter elements induce in liquid xenon. A silicon PIN diode was constructed to ensure that the Th228 source does not contaminate the system with the long-lived isotopes Th228 (T1/2 of 1.9 y) or Radium-224 (T1/2 of 3.6 d). The PIN diode was ...


A Study Of The Structure Of Light Tin Isotopes Via Single-Neutron Knockout Reactions, Andrew Franklin Ayres 2014 University of Tennessee - Knoxville

A Study Of The Structure Of Light Tin Isotopes Via Single-Neutron Knockout Reactions, Andrew Franklin Ayres

Doctoral Dissertations

The region around 100 Sn [100Sn] is important because of the close proximity to the N=Z=50 magic numbers, the rp process, and the proton drip-line. Alpha decay measurements show a reversal in the spin-parity assignments of the ground and first excited states in 101 Sn [101Sn] compared to 105 Te [105Te]. However, the lightest odd- mass tin isotope with a firm spin-parity assignment is 109 Sn [109Sn]. The d 5/2 [d5/2] and g 7/2 [g7/2] single-particle states above N=50 are near degenerate, evidenced by the excitation energy of the first excited state in ...


Thick Target Yield Of Th-229 Via Low Energy Proton Bombardment Of Th-232, Justin Reed Griswold 2014 University of Tennessee - Knoxville

Thick Target Yield Of Th-229 Via Low Energy Proton Bombardment Of Th-232, Justin Reed Griswold

Masters Theses

Actinium-225 is one of the more effective radioisotopes used in alpha radioimmunotherapy. Due to its ten-day half-life, it is more efficient to create its precursor, 229Th [Thorium-229] (t1/2[half-life] = 7932 ± 55 years). In this work, 229Th was produced via 40 MeV [Mega electron Volts] proton bombardment of a thick 232Th [Thorium-232] target. The irradiation took place at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Lab (ORNL). The target, consisting of 23 stacked natural thorium foils (137 mg/cm2 [milligrams per square centimeter] each), was irradiated with 50 nA [nanoamps] of ...


Yang-Mills Theories As Deformations Of Massive Integrable Models, Axel Cortes Cubero 2014 City University of New York, Graduate Center

Yang-Mills Theories As Deformations Of Massive Integrable Models, Axel Cortes Cubero

Dissertations and Theses, 2014-Present

Yang Mills theory in 2+1 dimensions can be expressed as an array of coupled (1+1)-dimensional principal chiral sigma models. The SU(N) principal chiral sigma model in 1+1 dimensions is integrable, asymptotically free and has massive excitations. We calculate all the form factors and two- point correlation functions of the Noether current and energy-momentum tensor, in

't Hooft's large-N limit (some form factors can be found even at finite N). We use these new form factors to calculate physical quantities in (2+1)-dimensional Yang-Mills theory, generalizing previous SU(2) by P. Orland to SU ...


Initial Conditions In High-Energy Collisions, Elena Petreska 2014 City University of New York, Graduate Center

Initial Conditions In High-Energy Collisions, Elena Petreska

Dissertations and Theses, 2014-Present

This thesis is focused on the initial stages of high-energy collisions in the saturation regime. We start by extending the McLerran-Venugopalan distribution of color sources in the initial wave-function of nuclei in heavy-ion collisions. We derive a fourth-order operator in the action and discuss its relevance for the description of color charge distributions in protons in high-energy experiments. We calculate the dipole scattering amplitude in proton-proton collisions with the quartic action and find an agreement with experimental data. We also obtain a modification to the fluctuation parameter of the negative binomial distribution of particle multiplicities in proton-proton experiments. The result ...


Ultrasonic Bonding For The Cuore Collaboration, John J. Sekerak II 2014 California Polytechnic State University - San Luis Obispo

Ultrasonic Bonding For The Cuore Collaboration, John J. Sekerak Ii

Physics

This paper will give the reader a brief introduction to the Standard Model, Neutrinoless Double Beta Decay, and the CUORE experiment under construction at Gran Sasso National Lab in Assergi, Italy. The remainder of the paper will describe the bonding process used to connect the heater pads and NTDs to the copper housings of the tower structure. Extensive details of the troubleshooting and calibration period are presented as a way for the reader to better understand the concepts involved during the bonding stage of the assembly process.


Monte Carlo Glauber Model Of Nuclear Collisions, Chad F. Rexrode 2014 California Polytechnic State University - San Luis Obispo

Monte Carlo Glauber Model Of Nuclear Collisions, Chad F. Rexrode

Physics

In order to understand the geometry of nuclear collisions, an iPython-based simulation of the Monte- Carlo Glauber model was created. The simulation utilizes nuclear charge density distributions to create nuclei and cross-section data from the Particle Data Group to generate large samples of nuclear collisions. The simulation correlates the number of nucleons participating in a collision as well as the number of binary collisions as a function of the impact parameter for each event. Good agreement between the program and expected results for Au+Au collisions at beam energies of 200 GeV is demonstrated. The program also makes predictions on ...


Use Of Positron Emission Tomography For Proton Therapy Verification, Jongmin Cho 2014 The University Of Texas Graduate School of Biomedical Sciences at Houston

Use Of Positron Emission Tomography For Proton Therapy Verification, Jongmin Cho

UT GSBS Dissertations and Theses (Open Access)

Positron emission tomography (PET), a tool commonly used for cancer staging and response monitoring, has recently been used for proton therapy verification. By imaging tissue activation following proton treatment, attempts have been made to verify proton dose and range. In this dissertation, two novel approaches were developed and tested for the purpose of help improve the proton dose and range estimation as well as verification.

Although there are still some challenges, attempts for proton dose verification using PET has been made by comparing Monte Carlo dose and PET simulations with treatment planned dose and measured PET. In this approach, generic ...


Neutron Polarimetry With Polarized 3he For The Npdgamma Experiment, Matthew Martin Musgrave 2014 University of Tennessee - Knoxville

Neutron Polarimetry With Polarized 3he For The Npdgamma Experiment, Matthew Martin Musgrave

Doctoral Dissertations

Cold neutrons enable the study of the fundamental interactions of matter in low-energy, low-background experiments that complement the efforts of high-energy particle accelerators. Neutrons possess an intrinsic spin, and the polarization of a beam of neutrons defines the degree to which their spins are oriented in a given direction. The NPDGamma experiment uses a polarized beam of cold neutrons to make a high precision measurement, on the order of one part in 100 million, of the parity-violating asymmetry in the angular distribution of emitted gamma-rays from the capture of polarized neutrons on protons. This asymmetry is a result of the ...


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