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Effective Field Theory Approach To Collective Motion In Atomic Nuclei, Eduardo Antonio Coello Perez 2015 University of Tennessee - Knoxville

Effective Field Theory Approach To Collective Motion In Atomic Nuclei, Eduardo Antonio Coello Perez

Doctoral Dissertations

Collective motion in heavy nuclei has been studied within collective and algebraic models, and within density functional theory. While they reproduce the energy spectra of these systems, their predictions for some electromagnetic transitions and moments do not lie within experimental uncertainty; in other words, these predictions are inconsistent with experimental data. An effective field theory approach to collective motion in heavy nuclei solves this long standing problem. Based on symmetry arguments only, the effective field theories, constructed as expansions in powers of a small parameter, consistently describe the energy spectra of nuclei exhibiting collective motion at low order in the ...


Methodology For Generating Simplified Cross Section Data Sets For Neutron Transport Calculations, Thomas Jay Harrison 2015 University of Tennessee - Knoxville

Methodology For Generating Simplified Cross Section Data Sets For Neutron Transport Calculations, Thomas Jay Harrison

Doctoral Dissertations

Neutron shielding problems involve radiation transport calculations over a wide range of energies. Fission neutrons have initial energy on the order of MeV, fusion neutrons have initial energy on the order of 10s of MeV, and space-origin neutrons have initial energy on the order of 100s of MeV or higher. Shielding calculations must track the neutrons from their initial energies until they are no longer of interest; for deep-penetration neutrons, this final energy can be on the order of eV before the neutron is no longer tracked. Thus, for deep-penetration space radiation shielding problems, the calculation may require tracking the ...


Installation And Alignment Of The N3he Experiment, Eric Lee Plemons 2015 University of Tennessee - Knoxville

Installation And Alignment Of The N3he Experiment, Eric Lee Plemons

Masters Theses

The n3He experiment is designed to probe the hadronic weak interaction by measuring the parity violating asymmetry between the spin of incoming neutrons and the momentum of outgoing protons following the nuclear break up of a helium three upon absorbing a neutron. Cold neutrons from the SNS are first polarized then allowed to impact a target chamber filled with helium three where the reaction occurs. Energetic particles resulting from the nuclear breakup ionize the helium three gas and are thereby detected as currents by an array of signal wires within the target chamber. In order to make a statistics limited ...


Hyperpolarized 129xe Magnetic Resonance Imaging Of Radiation-Induced Lung Injury, Ozkan Doganay 2015 The University of Western Ontario

Hyperpolarized 129xe Magnetic Resonance Imaging Of Radiation-Induced Lung Injury, Ozkan Doganay

Electronic Thesis and Dissertation Repository

Lung cancer is the largest contributor to cancer-related mortality worldwide. Only 20% of stage III non-small cell lung cancer patients survive after 5-years post radiation therapy (RT). Although RT is an important treatment modality for lung cancer, it is limited by Radiation-Induced Lung Injury (RILI). RILI develops in two phases: (i) the early phase (days-weeks) referred to radiation pneumonitis (RP), and (ii) the late phase (months). There is a strong interest in early detection of RP using imaging to improve outcomes of RT for lung cancer. This thesis describes a promising approach based on 129Xe gas as a contrast ...


Information Behaviors Of Nuclear Scientists At Korea Atomic Energy Research Institute, Youngchoon Chun, Jiho Yi, Jung-ran Park, Sangki Choi 2015 Korea Atomic Energy Research Institute

Information Behaviors Of Nuclear Scientists At Korea Atomic Energy Research Institute, Youngchoon Chun, Jiho Yi, Jung-Ran Park, Sangki Choi

Journal of East Asian Libraries

The goal of the study was to analyze the information use behaviors of researchers in the science and technology domain. A survey and interviews were conducted targeting nuclear scientists at the Korea Atomic Energy Research Institute. Study results indicate that the nuclear scientists mainly use the Institute library/information center and Internet portal/search engines during information acquisition. Easy access to information, accuracy, currency and cost are the most critical factors in selecting and obtaining information. The most frequently used database for executing research is the Institute’s electronic library (NUCLIS21) followed by the Citation Index SCOPUS. The results of ...


Effects Of A Periodic Decay Rate On The Statistics Of Radioactive Decay: New Methods To Search For Violations Of The Law Of Radioactive Change, Mark P. Silverman 2015 Trinity College

Effects Of A Periodic Decay Rate On The Statistics Of Radioactive Decay: New Methods To Search For Violations Of The Law Of Radioactive Change, Mark P. Silverman

Faculty Scholarship

It is a long-held tenet of nuclear physics, from the early work of Rutherford and Soddy up to present times that the disintegration of each species of radioactive nuclide occurs randomly at a constant rate unaffected by interactions with the external environment. During the past 15 years or so, reports have been published of some 10 or more unstable nuclides with non-exponential, periodic decay rates claimed to be of geophysical, astrophysical, or cosmological origin. Deviations from standard exponential decay are weak, and the claims are controversial. This paper examines the effects of a periodic decay rate on the statistical distributions ...


Low Intensity Gamma-Ray Spectroscopy Of The Lake Labyrinth Meteorite, Tristan C. Paul 2015 California Polytechnic State University - San Luis Obispo

Low Intensity Gamma-Ray Spectroscopy Of The Lake Labyrinth Meteorite, Tristan C. Paul

Physics

A 23.7g fragment of the Lake Labyrinth Meteorite (fell in 1924, collected in 1934 at Lake Labyrinth in South Australia, Australia) was re-investigated for evidence of the presence of 98Tc using a two dimensional low-intensity gamma-ray spectrometer. A new calibration technique using 26Al sources found the gamma-rays previously thought to be due to 98Tc are more likely from 166Ho. The presence of 166Ho is most likely due to activation of the stable 165Ho in the meteorite from terrestrial background sources where it was stored.


Effect Of Helium Ions Energy On Molybdenum Surfaces Under Extreme Conditions, Joseph Fiala, Jitendra K. Tripathi, Sean Gonderman, Ahmed Hassanein 2015 Purdue University

Effect Of Helium Ions Energy On Molybdenum Surfaces Under Extreme Conditions, Joseph Fiala, Jitendra K. Tripathi, Sean Gonderman, Ahmed Hassanein

The Summer Undergraduate Research Fellowship (SURF) Symposium

Plasma facing components (PFCs) in fusion devices must be able to withstand high temperatures and erosion due to incident energetic ion radiations. Tungsten has become the material of choice for PFCs due to its high strength, thermal conductivity, and low erosion rate. However, its surface deteriorates significantly under helium ion irradiation in fusion-like conditions and forms nanoscopic fiber-like structures, or fuzz. Fuzz is brittle in nature and has relatively lower thermal conductivity than that of the bulk material. Small amounts of fuzz may lead to excessive contamination of the plasma, preventing the fusion reaction from taking place. Despite recent efforts ...


Modern Study Of Environmental Pollution From The Emission Of Alpha Particles In Human Blood Samples In The City Of Najaf, Iraq, Basim A. Almayahi 2015 USM

Modern Study Of Environmental Pollution From The Emission Of Alpha Particles In Human Blood Samples In The City Of Najaf, Iraq, Basim A. Almayahi

21st International Conference on Environmental Indicators (ICEI 2015)

No abstract provided.


Design And Fabrication Of Liquid Scintillator Counter, Andrea Calderon Saucedo, John L. Orrell 2015 California State University - Long Beach

Design And Fabrication Of Liquid Scintillator Counter, Andrea Calderon Saucedo, John L. Orrell

STAR (STEM Teacher and Researcher) Program Posters

Pacific Northwest National Laboratory (PNNL) is currently developing an ultra-low background liquid scintillator counter (ULB LSC) in the shallow underground laboratory. At a depth of 35-meters water-equivalent, the underground laboratory has a multi-layered shielding to keep out cosmic-ray induced background. The ULB LSC, which is located in a clean room facility, is a multi-layered design made up of various materials, including plastic scintillator veto panels, borated polyethylene, lead and copper. These layers help lower the contributions of the terrestrial background and intrinsic background, resulting from the impurities present in the materials, to the overall background count rate observed by the ...


On The Spin Evolution Of Isolated Pulsars, Oliver Quinn Hamil 2015 University of Tennessee - Knoxville

On The Spin Evolution Of Isolated Pulsars, Oliver Quinn Hamil

Doctoral Dissertations

Neutron stars are the remnants of supernova explosions, and harbor the densest matter found in the universe. Because of their extreme physical characteristics, neutron stars make superb laboratories from which to study the nature of matter under conditions of extreme density that are not reproducible on Earth. The understanding of QCD matter is of fundamental importance to modern physics, and neutron stars provide a means of probing into the cold, dense region of the QCD phase diagram.

Isolated pulsars are rotating neutron stars that emit beams of electromagnetic radiation into space which appear like lighthouses to observers on Earth. Observations ...


Nucleosynthesis In Self-Consistent Core-Collapse Supernova Models Using Multidimensional Chimera Simulations, James Austin Harris 2015 University of Tennessee - Knoxville

Nucleosynthesis In Self-Consistent Core-Collapse Supernova Models Using Multidimensional Chimera Simulations, James Austin Harris

Doctoral Dissertations

Observations of nuclear abundances in core-collapse supernova (CCSN) ejecta, highlighted by γ-ray [gamma-ray] observations of the 44Ti [titanium-44] spatial distribution in the nearby supernova remnants Cassiopeia A and SN 1987A, allow nucleosynthesis calculations to place powerful constraints on conditions deep in the interiors of supernovae and their progenitor stars. This ability to probe where direct observations cannot makes such calculations an invaluable tool for understanding the CCSN mechanism. Unfortunately, despite knowing for two decades that supernovae are intrinsically multi-dimensional events, discussions of CCSN nucleosynthesis have been predominantly based on spherically symmetric (1D) models, which employ a contrived energy source ...


Cover, 2015 University of Tennessee, Knoxville

Cover

International Journal of Nuclear Security

No abstract provided.


Masthead, 2015 University of Tennessee, Knoxville

Masthead

International Journal of Nuclear Security

No abstract provided.


From The Editor, 2015 University of Tennessee, Knoxville

From The Editor

International Journal of Nuclear Security

No abstract provided.


Student Writing Competition, 2015 University of Tennessee, Knoxville

Student Writing Competition

International Journal of Nuclear Security

No abstract provided.


Measurements Of The Lead-Hydrocarbon Cross Section Ratio For Charged-Current Neutrino Interactions, William F. Bergan 2015 College of William and Mary

Measurements Of The Lead-Hydrocarbon Cross Section Ratio For Charged-Current Neutrino Interactions, William F. Bergan

Honors Theses

Studying the neutrino cross sections of various materials is of great importance in the analysis of data from neutrino oscillation experiments, as well as interesting in its own right. We have examined the charged-current muon neutrino cross section ratio between lead and scintillator, with our lead target being in the MINERvA electromagnetic calorimeter. This choice has allowed us to obtain usable efficiencies out to much larger muon angles than was feasible from the upstream targets. Comparing the cross section ratio in the data and Monte Carlo, we have found that the ratios agree reasonably well as a function of neutrino ...


Effect Of Hyperons On Pion Asymmetries Measured In The Qweak Experiment, Marcus S. Starman 2015 College of William and Mary

Effect Of Hyperons On Pion Asymmetries Measured In The Qweak Experiment, Marcus S. Starman

Honors Theses

Experimental nuclear physics has largely been concerned with testing the Standard Model of particle physics. The Qweak experiment was designed to measure the weak interaction force of the proton. The experiment was also used to make asymmetry measurements on pions produced by inelastic collisions. The asymmetry measured in the experiment for pions was larger than expected at lower momentums given the kinematic conditions. A possible cause for the larger asymmetry is the production of hyperons, which decay into pions that can be detected. This idea was investigated, and an acceptance function for these pions was formulated. The acceptance function took ...


Studies Of Polarized Helium-3 Cell Lifetimes, Andrew N. Smith 2015 College of William and Mary

Studies Of Polarized Helium-3 Cell Lifetimes, Andrew N. Smith

Honors Theses

This year I worked with Professor Averett to fill and analyze several $^3$He target cells. Many of these cells are taken from our lab to eventually be used as targets at Jefferson Lab for nuclear physics experiments. Our ultimate goal was to test a number of different variables in an attempt to improve the lifetimes of future targets. Over the course of this year we tested several different cells and eventually got some improvements in our cell lifetimes due to a couple factors, including a new tubing getter and larger cell size. We have not quite identified exactly what ...


Taming Of Monsters: The Postdramatic Case For Copenhagen, Shaan Y. Sharma 2015 College of William and Mary

Taming Of Monsters: The Postdramatic Case For Copenhagen, Shaan Y. Sharma

Honors Theses

Analysis of Michael Frayn's manipulation of perspective in his works, the implications of a postdramatic interpretation of Copenhagen, the production process of the show, and reflections on the performance.


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