Physics Commons^™

Effects Of Exposure To Atmospheric Humidity On Breakdown Field Strength Measurements Of Polymers, Megan Loveland Dewaal

Physics Capstone Projects

This study investigates the effects of absorbed water introduced via exposure to atmospheric humidity on electrostatic breakdown field strength measurements of polymers. Conducting breakdown tests under sample conditions appropriate for different applications is essential. If the breakdown field strength is overestimated for an application, an insulator may be used inappropriately in high electric fields where they are more likely to break down. Comparisons are made between: sets of pristine samples, samples that underwent a thorough vacuum bake out to remove absorbed water, and samples subject to subsequent incremental prolonged atmospheric exposure. These investigated the effects of absorbed water and determined …

Spacecraft Charging Test Considerations For Composite Materials, Allen Andersen, Wousik Kim, J. R. Dennison, Brian Wood, Todd A. Schneider, Jason Vaughn, Kenneth H. Wright Jr., Nelson W. Green, Eric Suh, Joel Schwartz, Abdul-Majeed Azad

Journal Articles

Composite materials present a growing challenge for spacecraft charging assessments. We review some recent lessons learned for charging tests of composite materials using both parallel-plate and electron beam test geometries. We also discuss examples of materials that exhibit significant variations between samples, despite them all having the same trade name.

A Study Of Electron Plasma Oscillations Using The Nimrod Code, Mckay Murphy

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A plasma, whether ”hot” or ”cold,” magnetized or unmagnetized, electrostatic or electromagnetic, exhibits normal modes of oscillation. Critical to understanding the stability of a plasma is the study of these normal modes. Waves originate from the long-range electric interactions between charged particles. This work will consider a class of waves known as Langmuir waves. These waves occur when a group of electrons are displaced with respect to the ions, with the electric Coulomb force playing the role of the restoring force of the oscillation [1]. Since the mass of ions is much greater than that of electrons, we can approximate …

Bifurcations And Hysteresis In The Dynamics Of Small Populations Of Spherical Magnets, Peter T. Haugen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

If you heat up some kinds of metals and then cool them down next to a magnet, they will be a magnet when they cool, but if they cool down away from a magnet, they will just be a lump of metal. This is an example of hysteresis and it’s very important for lots of technology. Another example of hysteresis might be a water tower pump that turns on when the tower is nearly empty and keeps going until the tower is nearly full. Whether or not the pump is on when the tower is half full depends on what …

Temperature Dependent Density Of States Models And Compiled Data For Radiation Induced Conductivity, Jodie Gillespie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Radiation Induced Conductivity (RIC) is the change in conductivity of a material due to bombardment from incident high energy radiation. RIC has consistently been found to follow a standard power law relation, 𝜎_𝑅𝐼𝐶(𝑇) = 𝑘_𝑅𝐼𝐶(𝑇)Ḋ^∆(𝑇), between conductivity, 𝜎_𝑅𝐼𝐶 and adsorbed dose rate, Ḋ. 𝑘_𝑅𝐼𝐶(𝑇) and ∆(𝑇) are material dependent parameters. Previous RIC models were developed in the 𝑇 → 0 limit. Now expanded models are developed in the low temperature limit (within a few 𝑘_𝐵𝑇 of the effective Fermi level) by approximating the Fermi-Dirac equation within a …

Investigating Atmospheric Gravity Waves Using 3-Dimensional Spectral Analysis, Kenneth I. Zia

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Atmospheric gravity waves (GW) are generated from the ground and go into the upper layers of the atmosphere where space begins. These waves have strong effects on the temperature and circulation of the Earth’s atmosphere. The temperature changes caused by these waves are observed through special cameras looking at light that the Earth’s atmosphere naturally emit at night. One of these cameras is placed at McMurdo Station, Antarctica where the long nights are used to see these waves longer than anywhere else. The images captured there are automatically analyzed to determine wave properties to better understand how often they are …

Serendipity Shape Function For Hybrid Fluid/Kinetic-Pic Simulations, Trevor V. Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Sun in our solar system and stars are capable of generating enormous amounts of energy. The process by which these gaseous, celestial bodies are able to produce such large amounts of energy is called thermonuclear fusion. Fusion happens when particles collide with one another at energy levels high enough to overcome the Coulomb force and then release vast amounts of energy. Plasma, the fourth state of matter, is the natural state of stars. Plasma is an ionized gas that consists of negatively and positively charged particles. Stars, which have immense mass, can confine the plasma through their gravity to …

Relativistic, Continuum Drift-Kinetic Capability In The Nimrod Plasma Fluid Code, Tyler Markham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A ”runaway” electron is an electron that, through a self-reinforcing process, accelerates to relativistic speeds. At multiple points during tokamak discharges, relativistic runaway electron (RE) beams can form. RE beams pose a serious risk in the form of severe damage to plasma facing components in ITER and future burning plasma reactors. Early RE studies used simplified geometric and transport models, but enabled feedback on the overall plasma evolution. This feedback is important for understanding the evolution of the RE current column. The work in this thesis is an important step toward self-consistently evolving an RE distribution in the plasma fluid …

Graviweak Theory In Bicomformal Space, Mubarak Ukashat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There are four basic forces in nature: the electromagnetic force, which accounts for interactions of particles with charges; the weak force, which is responsible for radioactive decay; the strong force, which holds the particles inside a nucleus tightly bound together; and the gravitational force, which is responsible for keeping us on our beautiful planet, Earth and holding together our entire solar system. Physicists have been on the hunt for a theory that can single-handedly explain all these forces under the same underlying mathematical formulation. So far, physicists have suceeded in unifying the electromagnetic and weak forces in what is called …

Inertial Motion On The Earth's Spheroidal Surface, Boyd F. Edwards, Cade Pankey, John M. Edwards

All Physics Faculty Publications

As seen by an observer in the rotating frame, the earth’s small spheroidal deformations neutralize the centrifugal force, leaving only the smaller Coriolis force to govern the “inertial” motion of objects that move on its surface, assumed smooth and frictionless. Previous studies of inertial motion employ weakly spheroidal equations of motion that ignore the influence of the centrifugal force and yet treat the earth as a sphere. The latitude dependence of these equations renders them strongly nonlinear. We derive and justify these equations and use them to identify, classify, name, describe, and illustrate all possible classes of inertial motion, including …

Round Robin Tests Of Electron Irradiated Polymers Via Pulsed Electroacoustic Measurements, Zachary Gibson, J. R. Dennison, Virginie Griseri

Physics Student Research

Charge accumulation and migration can be studied using the pulsed electroacoustic (PEA) method to directly measure internal charge distributions in dielectric materials. This study aims to compare measurements using PEA systems constructed in labs at Utah State University and Université Paul Sabatier to establish confidence in comparing PEA results between different PEA systems. While there is good agreement in data measured for pristine samples with DC bias applied and no charge embedded, there are discrepancies in the data when measuring irradiated samples with embedded charge. The overall characteristics of charge distributions measured with both systems is clearly the same, but …

Pulsed Electroacoustic Measurements Of Polymers Irradiated With Low Energy Monoenergetic Electrons, Zachary Gibson, Jr Dennison

Physics Student Research

Understanding the dynamics and accumulation of embedded charge in dielectric materials is paramount for many applications from HVDC power transmission to spacecraft charging. The pulsed electroacoustic (PEA) method allows for nondestructive measurements of embedded charge distributions in dielectrics. The spatial resolution of PEA measurements are typically ~10 μm. However, some of the most deleterious spacecraft charging events result from electron fluxes with 10 keV to 50 keV energies, resulting in electron ranges of 1's to 10's of μm. Due to the resolution of the PEA method and the superposition of the interfacial charge with the deposited charge distribution, it is …

Quantum Computing Simulation Of The Hydrogen Molecule System With Rigorous Quantum Circuit Derivations, Yili Zhang

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Quantum computing has been an emerging technology in the past few decades. It utilizes the power of programmable quantum devices to perform computation, which can solve complex problems in a feasible time that is impossible with classical computers. Simulating quantum chemical systems using quantum computers is one of the most active research fields in quantum computing. However, due to the novelty of the technology and concept, most materials in the literature are not accessible for newbies in the field and sometimes can cause ambiguity for practitioners due to missing details.

This report provides a rigorous derivation of simulating quantum chemistry …

Toward A Conceptual Approach To The Coriolis Force: Cataloging Intuitive Knowledge Elements In Intermediate Physics Learners, Jared B. Arnell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In Physics, the topic of the Coriolis force is often confusing and difficult to teach. I conducted a series of interviews with undergraduate physics students to understand how they would use their prior knowledge and personal experiences to interact with and navigate through a new conceptual teaching approach for the Coriolis force. Many students applied their intuitive understanding of balance to interpret and make predictions about the Coriolis force. Some students displayed a strong conviction that rotating objects will naturally get pulled outward, which suggests that this impression may be a useful tool for novice physics learners to use in …

Uncertainties Of The Pulsed Electroacoustic Method: Peak Positions Of Embedded Charge Distributions, Zachary Gibson, J. R. Dennison

Physics Student Research

The pulsed electroacoustic (PEA) method allows for nondestructive measurements of internal charge distributions in dielectric materials. These measurements have been paramount in understanding and mitigating charge accumulation, aging, and electrostatic discharge in materials for various applications. This study aims to examine more closely the uncertainties of pulsed electroacoustic measurements. The first few moments of a charge distribution are directly related to the magnitude, peak position, full-width-at-half-maximum, and skewness. The uncertainty in the magnitude of the charge distribution is often quite large, but the peak position can be determined with a precision of <1 μm. This has been demonstrated in our lab with repeated PEA measurements of polyether-etherketone (PEEK) with internal charge present. This precision is further validated with measurements of PEEK irradiated with differing doses of 50 keV incident electrons, resulting in peak positions that differ by only a few μm. A final test is given by measurements monitoring the slow migration of the charge distributions in these irradiated samples over several months. The measured shifts in the peak position of the charge distributions are ≤1 μm. Though the spatial resolutions of PEA measurements are typically ~10 μm, as defined by the full- width-at-half-maximum of the leading interfacial peak, the precision of the peak position can be more than an order of magnitude greater. The statistical analysis of the repeated measurements to determine uncertainties, as well as the validation measurements, demonstrate the high precision determination of the peak position of embedded charge distributions.

What Is A Photon? Foundations Of Quantum Field Theory, Charles G. Torre

All Physics Faculty Publications

This is a brief, informal, and relatively low-level course on the foundations of quantum field theory. The prerequisites are undergraduate courses in quantum mechanics and electromagnetism.

Introduction To Classical Field Theory, Charles G. Torre

All Complete Monographs

This is an introduction to classical field theory. Topics treated include: Klein-Gordon field, electromagnetic field, scalar electrodynamics, Dirac field, Yang-Mills field, gravitational field, Noether theorems relating symmetries and conservation laws, spontaneous symmetry breaking, Lagrangian and Hamiltonian formalisms.

Normal-Mode Oscillations For The Circular And Dipolar States Of A Filled Hexagonal Magnetic Dipole Cluster, Peter T. Haugen, Andrew D. P. Smith, Boyd F. Edwards

All Physics Faculty Publications

We analyze the rotational dynamics of six magnetic dipoles of identical strength at the vertices of a regular hexagon with a variable-strength dipole in the center. The seven dipoles spin freely about fixed axes that are perpendicular to the plane of the hexagon, with their dipole moments directed parallel to the plane. Equilibrium dipole orientations are calculated as a function of the relative strength of the central dipole. Small-amplitude perturbations about these equilibrium states are calculated in the absence of friction and are compared with analytical results in the limit of zero and infinite central dipole strength. Normal modes and …

Large Earthquakes' Effect On The Ionosphere, Aaron Houston

Physics Capstone Projects

The ionosphere is a part of the Earth’s atmosphere that stretches from 80 – 600 kilometers. Gases in this area are ionized which creates a range of free electrons that make up the plasma of the ionosphere. A group of these electrons is known as Total Electron Content (TEC), which is responsible for signal delays between satellites in orbit and their GPS receivers on the surface. Using this delay, the TEC in a specific region can be calculated. This helps in GPS error analysis. During the earthquake in Japan on March 11, 2011, there was allegedly a noticeable jump in …

Improving The Efficiency Of The Preconditioning Of Iterative Solutions To The Kinetic Equation, D. Caleb Price

Physics Capstone Projects

To achieve the reality of fusion, a greater understanding of plasma is required. The kinetic equation can be evolved simultaneously alongside the fluid equations to solve for kinetic closures. NIMROD performs this with numerical solvers where the General Minimum Residual (GMRES) solver becomes more efficient with a preconditioning matrix as input. Using a GPU-enabled library, the efficiency of GPU offloading to the preconditioning step was tested. A significant decrease in the factoring time of preconditioning matrix was observed. This suggests that the allocation of GPUs is worth investigating for NIMROD’s own benefit, but also anyone seeking to improve the efficiency …

Seasonal Variations In Global Ionospheric Total Electron Content, Jason Knudsen

Physics Capstone Projects

As the Sun ionizes atoms and molecules in the Earth’s ionosphere, the region of atmosphere above approximately 100 km in altitude, the created ionization in this region affects many of the systems that we rely on in daily life. This includes cellular service, GPS navigation, weather forecasting, and credit card data. A good measure for the level of ionization in the ionosphere is total electron content (TEC), which is the number of electrons in a square column above a given geographic location. The TEC over a geographic location influences the propagation of radio waves that traverse that section of the …

Acoustic Waves In The Upper Atmosphere, Geoffrey Blayne Schulthess

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Atmospheric waves can be generated by tropospheric sources such as earthquakes and explosions, causing significant disturbances in the upper atmosphere and ionosphere, where radio wave communications take place. For this analysis, they will be separated into two sub-groups called acoustic waves and gravity waves. Because each of these waves have unique frequency ranges, they can be observed and measured in order to determine their source type and location. Past studies attempted to build the connections between these waves with severe storms and earthquakes, which have improved our understanding of their complexity. Because of the complex nature of these waves, simplified …

Characteristics Of Mesospheric Temperature And Gravity Waves Over Chile In 2020-2021, Damien M. Devitt, Kenneth Zia

Physics Capstone Projects

Gravity waves (GWs) are often confused with gravitational waves in the fabric of space time. However, there is a clear distinction between them. Gravity wave is a term used by the atmospheric research field to describe perturbations in the atmosphere. Gravity pulls the perturbations down and causes oscillations, these present in the form of waves. The best visualization is to think of ripples on a pond, as the ripple reaches its peak gravity pulls the ripple down and creates an oscillating effect.

Yang-Mills Sources In Biconformal Double Field Theory, Davis W. Muhwezi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There is a robust and unifying approach to unraveling the roiling mysteries of the universe. Our most compelling accounts of physical reality at present rest on symmetry arguments that are conspicuously geometrical!

105 years ago, Albert Einstein derived gravity from Riemannian geometry. In the general theory of relativity, the world of our experience is a pseudo-Riemannian manifold whose curvature represents the gravitational field. Encoded in the Einstein field equation is how matter sources (energy-momentum tensor) couple to gravity (spacetime curvature). Schematically, the Einstein equation exhibits a more general structure:

Curvature of Spacetime = Material Sources

On one side of the …

Modeling The Effects Of Surface Roughness On Electron Yield, Trace Taylor, Matthew Robertson, Jr Dennison

Conference Proceedings

Surface conditions—including surface morphology, composition, contamination, and oxidation—can significantly affect electron yields and consequently spacecraft charging. The effects of surface roughness on electron yield are modeled in this study by considering four aspects of electron yield calculations: (i) simple models of rough surface geometry, (ii) the angular distributions of electrons emitted from various points on these surfaces, (iii) the likelihood of these emitted electrons escaping the rough surface, and (iv) the relative fractions of smooth and rough surfaces. Three simple periodic one-dimensional surface profiles were considered—namely rectangular, triangular, and sawtooth features; each surface profile was characterized by an aspect ratio …

Laboratory Simulations Of Simultaneous Reduced Gravity And Ionizing Radiation Environments, Achal Duhoon, Jr Dennison

Conference Proceedings

A novel system has been developed to simulate the combined effects of reduced gravity and ionizing radiation present during spaceflight on biological and particulate samples. The miniature rotary cell culture system (mRCCS) was designed to synchronously rotate up to five independent vessels containing particulate samples suspended in fluid media, constructed using radiation tolerant, biocompatible, and vacuum compatible materials. Reduced gravity conditions were achieved when particles (e.g., 200 µm polystyrene microcarrier beads with or without adhered cell clusters) were suspended inside the vessels moving near terminal velocity in viscous fluid media with densities matched to the suspended …

The Relevance Of Pulsed Electroacoustic Measurements For Spacecraft Charging, Zachary Gibson, J. R. Dennison

Physics Student Research

The magnitude and spatial distribution of charge embedded in dielectric materials and the evolution of the charge distributions with time are at the heart of understanding spacecraft charging. Spacecraft materials are charged primarily by incident fluxes of low energy electrons, with electron fluxes in the 10 keV to 50 keV range often responsible for the largest deleterious arcing effects. While the pulsed electroacoustic (PEA) method can provide sensitive non-destructive measurements of the internal charge distribution in insulating materials, it has often been limited for spacecraft charging applications by typical spatial resolutions of ≤10 μm, with a 10 μm range of …

Utah's Food Processing Industry Can Manufacture Products From Cbd-Containing Lipids That Have Superior Texture And Consistency, Joseph Cooney, Isaac Hilton

Research on Capitol Hill

Sophomore Joseph is an Honors student and Undergraduate Research Fellow studying physics. Freshman Isaac, of Kaysville, studies civil and environmental engineering. Joseph and Isaac are exploring how cannabinoids impact the way that lipids function. A common way CBD is packaged is within foods, where it is frequently added to fats like cocoa butter or palm oil, and as the market for such products increase producers need to understand CBD will change the behavior of the fats they are using.In addition to this work, Joseph also volunteers for a physics lab. “Undergraduate research has let me explore fields outside my major …

The Surface Conditions Of Spacecraft Panels May Significantly Affect Spacecraft Survivability, Trace Taylor

Research on Capitol Hill

USU junior Trace grew up in Brigham City and studies physics and electrical engineering. The majority of spacecraft failure is caused by electron charging on the outer surfaces of the craft. Additionally, contaminants on the craft can cause a film over surface panels, increasing the problem. Trace is studying how roughness on panels can mitigate this contamination as it affects the charging that can lead to craft failure. This research will help determine what optimal panel materials should be used in future spacecraft construction. Trace started research almost as soon as he came to campus in his freshman year, and …

Hysteretic Transition Between States Of A Filled Hexagonal Magnetic Dipole Cluster, Andrew D. P. Smith, Peter T. Haugen, Boyd F. Edwards

All Physics Faculty Publications

By minimizing the magnetostatic potential energy and by finding zeros in the sum of the squares of the torques, we find the equilibrium states of six dipoles of identical strength at the vertices of a regular hexagon and a variable-strength dipole at the center. The seven dipoles spin freely about fixed axes that are perpendicular to the plane of the hexagon, with their dipole moments directed parallel to the plane. When the central dipole is weak compared with the perimeter dipoles, a ‘‘circular’’ state applies in which the perimeter dipole moments circle around the central dipole, which points toward a …