Digital Commons Network^™

Curvature In Compressed Thin Cylindrical Shells Approaching The Isometric Limit, Nicole Voce

Senior Honors Projects, 2020-current

The ability to manipulate surface elastic instabilities finds many applications in engineering smart interfaces, e.g. in fluid-structure interaction and micro-fabrication. We study the buckling of a thin cylindrical shell constrained to slide onto an inner non-deformable pipe. Our goal is to characterize the relationship between the shell thickness and the localization of stresses by using curvature measurements. First, we induce surface buckling by immobilizing one end of the shell and applying force to the other end. Then, we obtain a virtual reconstruction of the surface from 3D optical scanning and compute the Gaussian curvature for every point on the mesh. …

Finding Strong Gravitational Lenses In The Desi Decam Legacy Survey, Xiaosheng Huang, Christopher Storfer, V. Ravi, A. Pilon, M. Domingo, D. J. Schlegel, S. Bailey, A. Dey, R. R. Gupta, D. Herrera, S. Juneau, M. Landriau, D. Lang, A. Meisner, J. Moustakas, A. D. Myers, E. F. Schlafly, F. Valdes, B. A. Weaver, J. Yang, C. Yèche

Physics and Astronomy

We perform a semi-automated search for strong gravitational lensing systems in the 9000 deg2 Dark Energy Camera Legacy Survey (DECaLS), part of the Dark Energy Spectroscopic Instrument Legacy Imaging Surveys. The combination of the depth and breadth of these surveys are unparalleled at this time, making them particularly suitable for discovering new strong gravitational lensing systems. We adopt the deep residual neural network architecture developed by Lanusse et al. for the purpose of finding strong lenses in photometric surveys. We compile a training sample that consists of known lensing systems in the Legacy Surveys and the Dark Energy Survey as …

Universality And Quantum Criticality In Quasiperiodic Spin Chains, Utkarsh Agrawal, Sarang Gopalakrishnan, Romain Vasseur

Publications and Research

Quasiperiodic systems are aperiodic but deterministic, so their critical behavior differs from that of clean systems and disordered ones as well. Quasiperiodic criticality was previously understood only in the special limit where the couplings follow discrete quasiperiodic sequences. Here we consider generic quasiperiodic modulations; we find, remarkably, that for a wide class of spin chains, generic quasiperiodic modulations flow to discrete sequences under a real-space renormalization-group transformation. These discrete sequences are therefore fixed points of a functional renormalization group. This observation allows for an asymptotically exact treatment of the critical points. We use this approach to analyze the quasiperiodic Heisenberg, …

Semiclassical Theory Of Laser-Assisted Radiative Recombination, Ilya I. Fabrikant, H. B. Ambalampitiya

Department of Physics and Astronomy: Faculty Publications

We study the process of laser-assisted radiative recombination of an electron with a proton by using a semiclassical approach involving calculation of classical trajectories in combined laser and Coulomb fields. Due to chaotic scattering in the combined fields, the radiation probability as a function of the impact parameter and the constant phase of the laser field exhibits chaotic behavior and fractal structures. We obtain a strong enhancement of the recombination cross section as compared to the laser-free case due to the Coulomb focusing effect. For sufficiently low incident electron velocities the cross section becomes infinite, and we limit it by …

A Physics-Based Machine Learning Study Of The Behavior Of Interstitial Helium In Single Crystal W–Mo Binary Alloys, Adib J. Samin

Faculty Publications

In this work, the behavior of dilute interstitial helium in W–Mo binary alloys was explored through the application of a first principles-informed neural network (NN) in order to study the early stages of helium-induced damage and inform the design of next generation materials for fusion reactors. The neural network (NN) was trained using a database of 120 density functional theory (DFT) calculations on the alloy. The DFT database of computed solution energies showed a linear dependence on the composition of the first nearest neighbor metallic shell. This NN was then employed in a kinetic Monte Carlo simulation, which took into …

On Quantum Effects Of Vector Potentials And Generalizations Of Functional Analysis, Ismael L. Paiva

Computational and Data Sciences (PhD) Dissertations

This is a dissertation in two parts. In the first one, the Aharonov-Bohm effect is investigated. It is shown that solenoids (or flux lines) can be seen as barriers for quantum charges. In particular, a charge can be trapped in a sector of a long cavity by two flux lines. Also, grids of flux lines can approximate the force associated with continuous two-dimensional distributions of magnetic fields. More, if it is assumed that the lines can be as close to each other as desirable, it is explained how the classical magnetic force can emerge from the Aharonov-Bohm effect. Continuing, the …

Discovering New Strong Gravitational Lenses In The Desi Legacy Imaging Surveys, Xiaosheng Huang, Christopher Storfer, A. Gu, V. Ravi, A. Pilon, W. Sheu, R. Venguswamy, S. Bankda, A. Dey, M. Landriau, D. Lang, A. Meisner, J. Moustakas, A. D. Myers, R. Sajith, E. F. Schlafly, D. J. Schlegel

Physics and Astronomy

We have conducted a search for new strong gravitational lensing systems in the Dark Energy Spectroscopic Instrument Legacy Imaging Surveys’ Data Release 8. We use deep residual neural networks, building on previous work presented in Huang et al. (2020). These surveys together cover approximately one third of the sky visible from the northern hemisphere, reaching a z-band AB magnitude of ∼ 22.5. We compile a training sample that consists of known lensing systems as well as non-lenses in the Legacy Surveys and the Dark Energy Survey. After applying our trained neural networks to the survey data, we visually inspect and …

Material Outgassing Kinetics: The Development Of A Testing Capability, Alex Kirkman

Physics Capstone Projects

Contamination due to outgassing of materials can cause the degradation of critical hardware of a spacecraft. Using outgassing rates, kinetic expressions can be developed and used in models to predict the evolution of molecules and migration of contaminants for specific materials. These models could be used in the selection process of materials to help mitigate the amount of contamination of mission critical hardware for the expected life of the spacecraft. By using the ASTM E1559 test standard this can be achieved. This standard uses the quartz crystal microbalance (QCM) collection approach. A temperature-controlled effusion cell, containing the sample material, impinges …

Optically Pumped Spin Polarization As A Probe Of Many-Body Thermalization, Daniela Pagliero, Pablo R. Zangara, Jacob Henshaw, Ashok Ajoy, Rodolfo H. Acosta, Jeffrey A. Reimer, Alexander Pines, Carlos A. Meriles

Publications and Research

Disorder and many body interactions are known to impact transport and thermalization in competing ways, with the dominance of one or the other giving rise to fundamentally different dynamical phases. Here we investigate the spin diffusion dynamics of ¹³C in diamond, which we dynamically polarize at room temperature via optical spin pumping of engineered color centers. We focus on low-abundance, strongly hyperfine-coupled nuclei, whose role in the polarization transport we expose through the integrated impact of variable radio-frequency excitation on the observable bulk ¹³C magnetic resonance signal. Unexpectedly, we find good thermal contact throughout the nuclear spin bath, …

The Parity-Violating Asymmetry In The N→Δ Transition At Low Q2, Thamraa A. Alshayeb

Doctoral Dissertations

Qweak has used the parity violating asymmetry to test the Standard Model (SM) by constantly flipping helicity states of a longitudinally polarized electron beam that scatters in the unpolarized LH2 target. The main focus of the Qweak experiment at Jefferson Lab was the recently published determination of the proton’s weak charge. In order to make corrections to the measured asymmetry at low 𝑄 2 due to inelastically scattered electrons, dedicated measurements were made of the parity violating asymmetry in the N→∆ transition at two different beam energies.

The measured inelastic asymmetries are used to extract the low energy constant dΔ, …

Electron Yield Of A Carbon Fiber Composite, Matthew Robertson

Utah Space Grant Consortium

As electron yield models continue to evolve and improve, a study of carbon fiber materials was conducted to try and understand more complex nanoscale structures and their influence on electron yield.

Fabrication Of Suspended Microbolometers On Soi Wafers, Isaac Maxfield

Physics Capstone Projects

A bolometer is a device to measure radiation energy by converting photon energy into heat on an isolated absorber. We plan to use carbon-nanotube (CNT) based absorber to enhance the photon absorption. The absorber is a few microns in size and is suspended with micron-sized bridges which also support metal lines for electrical measurements.

An Investigation Of Diode Failure, Nicholas James Adams

Physics

Solar electricity can be used to cheaply cook food and charge electronic devices. We investigate the viability of using diodes as heating elements for insulated solar electric cooking (ISEC). In addition, information on designing and constructing ISEC compatible phone chargers and rechargeable LED lighting systems is included.

Catalogue Of Computed Pseudo-Redshifts From Batse Grb Data, Rebecca M. Proni

Physics Theses - Archive

We present a catalog of the redshift estimates and probability distributions for 565 individual Short-duration Gamma-Ray Bursts (SGRBs) detected by the Burst And Transient Source Experiment (BATSE). This result is based on a careful classification and modeling of the population distribution of BATSE SGRBs in the 5-dimensional space of redshift as well as the intrinsic prompt gamma-ray emission properties: the isotropic 64ms peak luminosity, the total isotropic emission, the spectral peak energy, as well as the intrinsic duration, while taking into account the complex detection mechanism of BATSE and sample incompleteness. The underlying assumption in our modeling approach is that …

Construction Of A Hyperspectral Imager Using 3d-Printed And Off-The-Shelf Components, Joshua Moorhouse

Mechanical Engineering Undergraduate Honors Theses

The Arkansas Center for Space and Planetary Sciences is working in collaboration with the Mechanical Engineering department to create a relatively cheap and modifiable hyperspectral imager. It is constructed using 3D-printed and off-the-shelf components from Edmund Optics and Amazon. The iteration created in this paper delivers spectrograms in the visible spectrum. The long-term goals of the camera are to create hyperspectral images from these spectrograms and to advance the imager into the infrared and near-infrared spectra. This imager is being developed to be used in the Arkansas Center for Space and Planetary Sciences environmental test chambers to further the scientific …

Determining The Rotational And Orbital Velocities Of Objects In The Solar System, Mark Jones

Undergraduate Honors Theses

Astronomers have been observing the night sky for many centuries to establish a better understanding for our universe and solar system. As part of their observations, astronomers characterize celestial bodies by fundamental properties such as mass, motion, and composition in order to provide further insight about the objects in question. As technology and science have evolved, the methods for measuring these properties have become more precise and accurate. One such methodology is known as spectroscopy, and it is a significant tool for observational astronomy. In this paper, we shall describe how we used astronomical spectroscopy to determine orbital and rotational …

Lunar Mining: Designing A Robust Robotic Mining System, Ted Goodell, James Ehlers, Rian Simpson, Tina Hayward, Ali Almiskeen, Logan Peterson, Joshua Miraglia, Alexander Charters, Palmer Clegg, Chandler Millar, Emerson Labon, Jonathan Warner, Matthew Cohen, Evan Cleveland, Jackson Dean, Todd Renner, Sergio Nunez, Pramit Chalise, Arthur Steur, Jake Erickson, Kenny Ho

Utah Space Grant Consortium

The annual NASA Robotic Mining Challenge: Lunabotics tasks teams with building robots capable of traversing and mining simulated Lunar terrain. The competition goal is to utilize automation and sensing alongside mechanical systems to harvest icy regolith (gravel) from beneath the satellite’s surface.

This year, Utah Student Robotics sought to improve upon the design from last year. The 2019-2020 rover is based on proven NASA concepts, such as the RASSOR 2.0 digging drum, and the Rocker-Bogie mobility platform.

Computational Analysis Of A New Planar Mixing Layer Flame Configuration To Study Soot Inception, Carmen Ciardiello

Honors Scholar Theses

The production of soot is omnipresent in society today. Soot is the product of many of the combustion processes that provide the bulk of the usable energy throughout the world. Furthermore, soot particulate poses a great danger to both the environment and all forms of life on Earth. It has proven to pollute ecosystems, foster health problems for human beings, and degrade air quality [1].

These dangers make studying and understanding soot particulate paramount for improving the quality of life. Thus, this study introduces a new flame configuration for studying soot inception. Presently, various common flame configurations have been found …

Changes In The Scattering Phase Shifts For Partial Waves Of Ultracold Particles At Different Energies, Kaaviyan Faezi

Honors Scholar Theses

At low energies, scattering phase shifts, the difference in phases between the incoming and outgoing spherical waves in scattering, for different partial waves follow a similar pattern. The phase shift curves, which are a function of the angular momentum quantum number for different scattering energy, obtain resonances after reaching their maxima, and as energy is increased, these resonances become smaller and eventually disappear. Using numerical methods involving the use of Chebyshev polynomials, we solve the wave equation for a scattering potential to obtain the radial equation. From the radial equation we then find the scattering phase shift for a particular …

Topography Estimation Using Particle Swarm Optimization, Yelbir Kazhykarim

Theses and Dissertations

The Earth’s Vertical Gravity Gradient (VGG) can be used to map seafloor topography but presents a challenging inverse problem. A promising approach is forward modeling, in which one searches over a set of candidate topographies and selects the one whose predicted VGG best fits the observed one. The main bottleneck here is solving the associated high-dimensional and non-linear optimization problem. Yang et al (2018) demonstrated a method in which the topography is parametrized by heights of mass elements on a rectangular grid and the ≈ 104 dimensional optimization problem is tackled with simulated annealing (SA). We propose a computationally much …

Richardsite, Zn2cugas4, A New Gallium-Essential Member Of The Stannite Group From The Gem Mines Near Merelani, Tanzania, Luca Bindi, John A. Jaszczak

Michigan Tech Publications, Part 1

The new mineral richardsite occurs as overgrowths of small (50–400 μm) dark gray, disphenoidal crystals with no evident twinning, but epitaxically oriented on wurtzite–sphalerite crystals from the gem mines near Merelani, Lelatema Mountains, Simanjiro District, Manyara Region, Tanzania. Associated minerals also include graphite, diopside, and Ge,Ga-rich wurtzite. It is brittle, dark gray in color, and has a metallic luster. It appears dark bluish gray in reflected plane-polarized light, and is moderately bireflectant. It is distinctly anisotropic with violet to light-blue rotation tints with crossed polarizers. Reflectance percentages for Rmin and Rmax in air at the respective wavelengths are 23.5, 25.0 …

Effects Of Incubation Temperature On Nanomechanical Properties Of Β-Lactoglobulin Amyloid Fibers, Santosh Khatri

Theses and Dissertations

Amyloid fibrils constitute a class of highly ordered nanomaterials formed by aggregates of the protein. Although The irreversible fibril formation of various proteins is related to the disorders like Alzheimer’s diseases, Creutzfeldt-Jacob and many more, amyloid fibrils have also been noticed in many physiologically beneficial roles such as in adhesive and hormone storage. Here, we compare the stiffness and structural properties of the amyloid fibers examined by the statistical approaches of single molecule atomic force microscopy images of heat-denatured β-lactoglobulin fibrils at different incubation time period (24, 48, and 72 hours). We demonstrate the gradual decrease in stiffness of the …

Monte Carlo Simulations Of Ultracold Neutron Velocities, Isaiah Cox

Undergraduate Honors Theses

An electric dipole moment (EDM) in the neutron would indicate a source of CP-violation that is needed to explain the dominance of matter over antimatter in the universe. Several experiments are currently looking for a neutron EDM and so far, the value has been constrained to d_n 1.8 x10 ²⁶ ecm. Presented here is work supporting the nEDM experiment at Los Alamos National Laboratory which utilizes ultracold neutrons (UCNs) and Ramsey’s separated oscillating fields method. In such an experiment, it is important to understand the velocity of the neutrons due to false EDM signals that can be pro- duced …

Constraining Neutron Star Nuclear Equations Of State Based On Observational Data, Alexander Clevinger

Undergraduate Honors Thesis Projects

This project analyzes recent observational data of neutron stars. It uses this to data to constrain nuclear equations of state proposed by Oter. et al. based on the maximum masses proposed by these equations of state. I do this by using numerical integration of the Tolman-Oppenheimer-Volkov equation to provide equilibrium states for each proposed EoS.

Design Of Submicron Structured Guided-Mode-Resonance Near-Infrared Polarizer, Marzia Zaman

Graduate Theses and Dissertations

The objective of this research is to design a larger submicron linear polarizer in the near-infrared wavelength range with a wide bandwidth which can be fabricated using the conventional thin-film microfabrication technology to reduce cost. For this purpose, a gold (Au) wire-grid transmission-type transverse-magnetic (TM) polarizer and a silicon (Si) wire-grid reflection-type TM polarizer, were designed using the guided-mode-resonance filter. The Au wire-grid TM polarizer of 700nm grating width and 1200nm grating period has 95% transmittance at 2400nm, more than 1000nm resonance peak bandwidth, and an extinction ratio (ER) of around 300 with a moderated level of sidebands. The 700nm …

Consistency Checks For Two-Body Finite-Volume Matrix Elements. Ii. Perturbative Systems, Raúl A. Briceño, Maxwell T. Hansen, Andrew W. Jackura

Physics Faculty Publications

Using the general formalism presented in [Phys. Rev. D 94, 013008 (2016); Phys. Rev. D 100, 034511 (2019)], we study the finite-volume effects for the 2 þ J → 2 matrix element of an external current coupled to a two-particle state of identical scalars with perturbative interactions. Working in a finite cubic volume with periodicity L, we derive a 1=L expansion of the matrix element through O(1=L⁵) and find that it is governed by two universal current-dependent parameters, the scalar charge and the threshold two particle form factor. We confirm the result through a numerical study of the …

Model-Based Properties Of Earth's Protective Shield: Relating Ut-Based Dependencies Of The Open/Closed Boundary, Cutoff Latitude, And L-Shell Parameter With Polar Cap Absorption Events, David A. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High frequency radio continues to be an important communications medium. For example, commercial airlines use high frequency radios as their primary communications mode during transpolar crossings. It has been estimated that over 7000 transpolar flights occur each year. Unfortunately, during geomagnetic storms high frequency communications can become unreliable, especially near Earth's Polar Regions.

Space weather forecasters are burdened with the responsibility of predicting how radio signals might be affected during geomagnetic storms and passing that important information on to commercial airlines, allowing them to adjust flight plans accordingly. Such adjustments can be costly, but are necessary to ensure safety of …

Hdr Brachytherapy For Skin Cancer Using H.A.M. Applicator, Timothy Richard Thatcher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Skin cancer is the most common type of malignancy affecting both men and women in the United States. A majority of these cases are nonmelanoma skin cancers (NMSC) such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). The goal of any skin cancer treatment is to cure the lesion itself while also preserving function and optimizing superficial cosmesis. High dose rate (HDR) brachytherapy provides an alternative to superficial x-ray or electron beam for skin cancer treatment. Utilizing an Iridium 192 source soldered to the end of a wire, surface dose can be administered at predetermined positions with sharper …

Searching For Optical Counterparts To Gravitational Waves, Richard Camuccio

Theses and Dissertations

The era of multi-messenger astronomy has begun. The coordinated activities of multiple, distinct observatories play a critical role in both responding to astrophysical transients and building a more comprehensive interpretation otherwise inaccessible to individual observations. The Transient Robotic Observatory of the South (TOROS) Collaboration has a global network of instruments capable of responding to several transient targets of opportunity. The purpose of this thesis is to demonstrate how optical observatories with small fields of view (degree) can follow up and observe astrophysical transients. TOROS facilities responded to three unique gravitational wave events during the second and third observational campaigns of …

A Study Of Optical Nonlinearities At The Single-Photon Level For Quantum Logic, Balakrishnan Viswanathan

Graduate Theses and Dissertations

In this dissertation, we shall focus on theoretically studying quantum nonlinear optical schemes to construct a conditional phase gate at the single-photon level. With an aim to develop analytical models, we shall carry out a rigorous quantized multimode field analysis of some of these schemes involving only the interacting field operators. More specifically, we shall first study the three-wave mixing process involving two single-photons in a second-order nonlinear medium (x(2)) under two different cases viz. when the photons are traveling with equal velocities and when they are traveling with different velocities, and explore the possibility of using them for building …