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Measurement Of The Β-Decay Properties Of A=105 Isotopes Using The Modular Total Absorption Spectrometer And The Development Of The Beta Spectrum Module, Thomas J. Ruland

LSU Doctoral Dissertations

Nuclear reactors produce an extremely diverse population of beta-decaying isotopes. Accurate and precise knowledge of the beta-decay properties of these isotopes is vital to safe reactor operations as well as informing next-generation reactor design. These beta-decay properties not only impact the design and operation of nuclear reactors, but they influence the expected antineutrino flux and spectrum measured from nuclear reactors. Historical measurements of many of these isotopes are subject to a systematic bias referred to as the Pandemonium Effect, because the low-efficiency, high-precision detectors used to perform the measurements results in misinterpreting weak gamma cascades from high- energy levels as …

Interfacial And Surface Magnetism In Epitaxial Nico2O4(001)/Mgal2O4 Films, Corbyn Mellinger, Xiao Wang, Arjun Subedi, Andy T. Clark, Takashi Komesu, Richard Rosenberg, Peter A. Dowben, Xuemei Cheng, Xiaoshan S. Xu

Department of Physics and Astronomy: Faculty Publications

NiCo₂O₄ (NCO) films grown on MgAl₂O₄ (001) substrates have been studied using magnetometry and x-ray magnetic circular dichroism based on x-ray absorption spectroscopy and spin-polarized inverse photoemission spectroscopy with various thicknesses down to 1.6 nm. The magnetic behavior can be understood in terms of a layer of optimal NCO and an interfacial layer (1.2 ± 0.1 nm), with a small canting of magnetization at the surface. The thickness dependence of the optimal layer can be described by the finite-scaling theory with a critical exponent consistent with the high perpendicular magnetic anisotropy. The interfacial layer …

Cms Pythia 8 Colour Reconnection Tunes Based On Underlying-Event Data, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

New sets of parameter tunes for two of the colour reconnection models, quantum chromodynamics-inspired and gluon-move, implemented in the pythia 8 event generator, are obtained based on the default CMS pythia 8 underlying-event tune, CP5. Measurements sensitive to the underlying event performed by the CMS experiment at centre-of-mass energies √ s = 7 and 13 TeV, and by the CDF experiment at 1.96 TeV are used to constrain the parameters of colour reconnection models and multiple-parton interactions simultaneously. The new colour reconnection tunes are compared with various measurements at 1.96, 7, 8, and 13 TeV including measurements of the underlying-event, …

Method Of Evanescently Coupling Whispering Gallery Mode Optical Resonators Using Liquids, Hengky Chandrahalim, Kyle T. Bodily

AFIT Patents

The present invention relates to evanescently coupling whispering gallery mode optical resonators having a liquid coupling as well as methods of making and using same. The aforementioned evanescently coupling whispering gallery mode optical resonators having a liquid couplings provide increased tunability and sensing selectivity over current same. The aforementioned. Applicants’ method of making evanescent-wave coupled optical resonators can be achieved while having coupling gap dimensions that can be fabricated using standard photolithography. Thus economic, rapid, and mass production of coupled WGM resonators-based lasers, sensors, and signal processors for a broad range of applications can be realized.

Effective Non-Hermiticity And Topology In Markovian Quadratic Bosonic Dynamics, Vincent Paul Flynn

Dartmouth College Ph.D Dissertations

Recently, there has been an explosion of interest in re-imagining many-body quantum phenomena beyond equilibrium. One such effort has extended the symmetry-protected topological (SPT) phase classification of non-interacting fermions to driven and dissipative settings, uncovering novel topological phenomena that are not known to exist in equilibrium which may have wide-ranging applications in quantum science. Similar physics in non-interacting bosonic systems has remained elusive. Even at equilibrium, an "effective non-Hermiticity" intrinsic to bosonic Hamiltonians poses theoretical challenges. While this non-Hermiticity has been acknowledged, its implications have not been explored in-depth. Beyond this dynamical peculiarity, major roadblocks have arisen in the search …

Unraveling The Quantum Hall Effects: From Conformal Field Theory Inspired Tensor Networks To Interacting Many-Body Simulations, Matheus Schossler

Arts & Sciences Graduate Student Theses and Dissertations

Systems confined in the two-dimensional world have long played a major role in physics. Under a quantizing magnetic field, these systems can exhibit phases of matter described by beautiful trial wave functions. Although there are numerous solvable models for fractional quantum Hall (FQH) physics, they are primarily developed and studied from the viewpoint of clustering properties of these wave functions in first quantization. Here we investigate frustration-free Hamiltonians of FQH states and their connection with 1D tensor networks, or matrix product state (MPS), based on the conformal field theory (CFT) representation of their ground and excited states. Examining these Hamiltonians …

Abundances Of Ultra-Heavy Cosmic Ray Nuclei With Calet, Wolfgang Vaughn Zober

Arts & Sciences Graduate Student Theses and Dissertations

This work describes the determination of the relative abundances of the Galactic Cosmic-Ray (GCR) nuclei from Z=9 through Z=40, with preliminary measurements up to Z=44, using the Calorimetric Electron Telescope (CALET) on board the International Space Station (ISS). This analysis will compare results with the top-of-atmosphere abundances from the balloon-borne SuperTIGER and top-of-instrument abundances from the space missions, ACE-CRIS and HEAO-3. This analysis also provides insight into the potential opportunities and challenges for a future SuperTIGER-like mission on the ISS.Our analysis looks at work on two separate but complementary aspects of the Ultra-Heavy (UH) analysis in CALET. CALET has a …

A Framework For Investigating Random Ensembles Of Structured Ecosystems And Quantifying Their Emergent Coarse-Grainability, Jacob Moran

Arts & Sciences Graduate Student Theses and Dissertations

The interface between statistical physics and theoretical ecology has a long history, employing powerful concepts such as ensemble approaches and typicality to study emergent properties of ecosystems. This of course raises the question of what ensembles are useful to describe the typical behaviors of evolution and ecology, but so far, the traditional context of high-diversity ecology has considered ensembles of random, unstructured ecosystems. Although much insight has been gained in this regime, one naturally wonders how representative are random ensembles of real, natural ecosystems that are arguably atypical and highly structured by evolution. Moreover, the question of coarse-graining ecosystems has …

A Torsion Balance Search For Long-Range Interactions Coupling To Baryons And Leptons And Cosmic Ray Transport For Spatially And Temporally Continuous And Discrete Sources, Dawson Huth

Arts & Sciences Graduate Student Theses and Dissertations

Part I: The expectation of new physics motivates more stringent tests of our current best understanding of gravitation, General Relativity (GR). Many theories proposing new physics predict the violation of Einstein’s equivalence principle, a set of criteria which must hold for GR to be valid. A torsion balance instrument was designed and operated to detect any violation of the equivalence principle. The motivations for performing such an experi- ment, instrument design, operational principles, data collected and subsequent analysis are described in detail in this thesis. After 51 days of continuous data collection experimental upper bounds on the violation of the …

Experimental Investigation Of Non-Hermiticity In Quantum Systems, Maryam Abbasi

Arts & Sciences Graduate Student Theses and Dissertations

The investigation of quantum systems in experimental setups involves interaction with the environment, which introduces channels of dissipation. These systems can be described by a non-Hermitian Hamiltonian, capturing the effect of gain and loss. Realizing these systems in classical cases demonstrates interesting phenomena such as topological features in the optical and mechanical domain, energy transfer, and enhancement in sensing. The primary focus of this thesis is the realization of the non-Hermiticity in a quantum system. To accomplish this, we harness multiple energy levels of an anharmonic superconducting circuit with coupling to an engineered bath to investigate the static and dynamic …

Studying Quantum Memory Effects Of The Environment With Superconducting Circuits, Daria Kowsari

Arts & Sciences Graduate Student Theses and Dissertations

The presence of the environment in real-world experiments which strive to harness quantum mechanical effects is inevitable. This results in dissipation, which is known to be the main source of errors that prevent us from building a practical quantum computer. Nevertheless, one can employ the environment as a resource, especially when there is a strong coupling between the system and its environment. In this regime, the dynamics of the system is governed by the generalized Nakajima-Zwanzig master equation incorporating all the memory effects induced by the environment. The existence of memory allows us to investigate intriguing phenomena, such as the …

Spectro-Polarimetric And Time Domain Characteristics Of Dynamically Evolving Accretion Flows From The General Relativistic Raytracing Of General Relativistic Magneto-Hydrodynamical Simulations, Andrew West

Arts & Sciences Graduate Student Theses and Dissertations

Black holes are among the most exotic phenomena in our universe, physical objects so dense and compact that within their horizon not even light can escape. In binary systems, black holes can accrete material from their companion star, forming an accretion disk that is subjected to extreme physical conditions. Often, these disks are accompanied by jets - highly relativistic outflows of material moving at significant fractions of the speed of light. This extreme environment is the source of some of the most luminous and energetic processes in our universe. Black hole accretion disks are often modeled as a steady state, …

A Stochastic Search For Intermittent Gravitational-Wave Backgrounds, Jessica Lawrence, Kevin Turbang, Andrew Matas, Arianna I. Renzini, Nick Van Remortel, Joseph D. Romano

Physics & Astronomy Faculty Publications

A likely source of a gravitational-wave background (GWB) in the frequency band of the Advanced LIGO, Virgo, and KAGRA detectors is the superposition of signals from the population of unresolvable stellar-mass binary-black-hole (BBH) mergers throughout the Universe. Since the duration of a BBH merger in band (similar to 1 s) is much shorter than the expected separation between neighboring mergers (similar to 103 s), the observed signal will be "popcornlike" or intermittent with duty cycles of order 10-3. However, the standard cross-correlation search for stochastic GWBs currently performed by the LIGO-Virgo-KAGRA Collaboration is based on a continuous-Gaussian signal model, which …

A Study Of Data/Monte Carlo Agreement In Charmed Baryon Decays At Belle Ii, Kaitlyn Thurmond

Honors Theses

The Belle II experiment at the SuperKEKB electron-positron accelerator facility in Tsukuba, Japan has a primary goal of searching for new physics beyond the Standard Model of particle physics. Extremely precise measurements of particle decays will be compared with Standard Model predictions in order to expose the presence of new particles and interactions. These measurements are prepared using simulated samples to avoid potential biases when studying the data. The Belle II collaboration produces two types of simulated samples for this purpose. One is produced with consistent calibration payloads and another with payloads calibrated as a function of data taking. This …

Photophysical And Photochemical Processes In Small Molecules And Materials For Solar Energy Conversion, Ethan Lambert

Honors Theses

The work covered in this thesis all falls under the theme of photophysical processes after light and matter interact. Those of primary interest are Raman scattering induced vibrations and excited state dynamics probed by transient absorption spectroscopy. Small molecules are studied with Raman spectroscopy and computational chemistry. These studies unearth the shifts in vibrational frequency as a function of charge transfer or receipt and how a quantitative assay of natural orbital populations and delocalization can offer both the nature and magnitude of this charge transfer. Further, a method is presented that builds upon previous work within the academic family tree; …

Rigorous Analysis Of Markov Processes With Applications To Quantum Information, Samuel Edwin Slezak

Physics & Astronomy ETDs

We present a rigorous analysis of the rapid convergence of techniques based on Markov chains for the simulation of thermal quantum systems. We show that a classical computing algorithm called path integral Monte Carlo is capable of simulating thermal states of transverse field Ising models above a threshold temperature by demonstrating the existence of a rapidly mixing Markov chain. We then turn to quantum computing algorithms and show that an idealized version of quantum Metropolis sampling can efficiently simulate systems that satisfy the eigenstate thermalization hypothesis. In a related result, we find a class of stoquastic frustration free Hamiltonians that …

Photonic Sensors Based On Integrated Ring Resonators, Jaime Da Silva

Mechanical Engineering Research Theses and Dissertations

This thesis investigates the application of integrated ring resonators to different sensing applications. The sensors proposed here rely on the principle of optical whispering gallery mode (WGM) resonance shifts of the resonators. Three distinct sensing applications are investigated to demonstrate the concept: a photonic seismometer, an evanescent field sensor, and a zero-drift Doppler velocimeter. These concepts can be helpful in developing lightweight, compact, and highly sensitive sensors. Successful implementation of these sensors could potentially address sensing requirements for both space and Earth-bound applications. The feasibility of this class of sensors is assessed for seismic, proximity, and vibrational measurements.

An Analysis Of Detection Asymmetry Using Baryon Decays In Belle Ii, Matthew Mestayer

Honors Theses

The purpose of this study was to determine the detection asymmetry of the Belle II detector using decays of two common baryons, Λ⁰ → ��π^- and Σ⁺ → ��π⁰. A Monte Carlo simulation of both decays was used to determine the validity of signal isolation criteria. These criteria were then applied to the Belle II data, allowing for a comparison of the detection asymmetry in the data relative to the simulation. The results show a moderate detection asymmetry when using the Λ⁰ → ��π^- decay, particularly for forward-going baryons. For the Σ^{+ …}

Assorted Kerosene-Based Nanofluid Across A Dual-Zone Vertical Annulus With Electroosmosis, Sara I. Abdelsalam, A. M. Alsharif, Y. Abd Elmaboud, A. I. Abdellateef

Basic Science Engineering

The goal of this numerical simulation is to visualize the electroosmotic flow of immiscible fluids through a porous medium in vertical annular microtubes. The inner region (Region I) is filled with an electrically conducting hybrid nanofluid while an electrically conducting Jeffrey fluid is flowing in the second region (Region II). The chosen nanofluid is kerosene-based and the nanoparticles (Fe3O4-TiO2) are of a spherical shape. A strong zeta potential is taken into account and the electroosmotic velocity in the two layers is considered too. The annular microtubes are subjected to an external magnetic field and an electric field. The linked nonlinear …

Mechanobiology As A Tool For Addressing The Genotype-To- Phenotype Problem In Microbiology, Merrill E. Asp, Minh-Tri Ho Thanh, Subarna Dutta, Jessica A. Comstock, Roy D. Welch, Alison E. Patteson

Physics - All Scholarship

The central hypothesis of the genotype–phenotype relationship is that the phenotype of a developing organism (i.e., its set of observable attributes) depends on its genome and the environment. However, as we learn more about the genetics and biochemistry of living systems, our understanding does not fully extend to the complex multiscale nature of how cells move, interact, and organize; this gap in understanding is referred to as the genotype-to-phenotype problem. The physics of soft matter sets the background on which living organisms evolved, and the cell environment is a strong determinant of cell phenotype. This inevitably leads to challenges as …

U-No: U-Shaped Neural Operators, Md Ashiqur Rahman, Zachary E Ross, Kamyar Azizzadenesheli

Department of Computer Science Faculty Publications

Neural operators generalize classical neural networks to maps between infinite-dimensional spaces, e.g., function spaces. Prior works on neural operators proposed a series of novel methods to learn such maps and demonstrated unprecedented success in learning solution operators of partial differential equations. Due to their close proximity to fully connected architectures, these models mainly suffer from high memory usage and are generally limited to shallow deep learning models. In this paper, we propose U-shaped Neural Operator (U-NO), a U-shaped memory enhanced architecture that allows for deeper neural operators. U-NOs exploit the problem structures in function predictions and demonstrate fast training, data …

Monolithic Multiphysics Simulation Of Hypersonic Aerothermoelasticity Using A Hybridized Discontinuous Galerkin Method, William Paul England

Theses and Dissertations

This work presents implementation of a hybridized discontinuous Galerkin (DG) method for robust simulation of the hypersonic aerothermoelastic multiphysics system. Simulation of hypersonic vehicles requires accurate resolution of complex multiphysics interactions including the effects of high-speed turbulent flow, extreme heating, and vehicle deformation due to considerable pressure loads and thermal stresses. However, the state-of-the-art procedures for hypersonic aerothermoelasticity are comprised of low-fidelity approaches and partitioned coupling schemes. These approaches preclude robust design and analysis of hypersonic vehicles for a number of reasons. First, low-fidelity approaches limit their application to simple geometries and lack the ability to capture small scale flow …

Pairing And Rotation-Induced Nuclear Exotica In Covariant Density Functional Theory, Saja Teeti

Theses and Dissertations

Covariant density functional theory (CDFT) is one of the modern theoretical tools for describing the nuclear structure physics of finite nuclei. Its performance is defined by underlying covariant energy density functionals (CEDFs). In this dissertation and within the framework of the CDFT, different physical properties of the ground and the excited states of rotating and non-rotating nuclei have been investigated.

A systematic global investigation of pairing properties based on all available experimental data on pairing indicators has been performed for the first time in the framework of covariant density functional theory. It is based on separable pairing interaction of Ref.\ …

Oxidation Resistance Of An Atomically Flat Cu(111) Surface: A First-Principles Study, Bipin Lamichhane

Theses and Dissertations

The first-principles calculation based on density functional theory (DFT) was used to study the oxidation resistance of atomically flat and atomic-step edges of Cu(111), diffusion of Cu atoms in different surfaces of alumina and interface properties of alumina and Cu(111), and magnetic properties of Mn-substituted strontium hexaferrite. The dissociation of oxygen molecules is the primary reason for the corrosion of metals, which deteriorates their application. Cu(111) flat surface, mono-atomic, and multi-atomic step edges were used to study oxygen diffusion. Penetration of oxygen on a Cu(111) flat surface requires high energy, indicating oxidation resistance. Our DFT result of oxygen diffusion into …

Origin And Structure Of The First Sharp Diffraction Peak Of Amorphous Solids, Devilal Dahal

Dissertations

Several explanations have been reported in the literature about the origin of extended-range oscillations (EROs) in the atomic pair-correlation function of amorphous materials. Although the radial ordering beyond the short-range order of about 5 Å has been extensively studied in amorphous materials, the exact nature of the radial ordering beyond a nanometer is still not resolved. This dissertation address this problem and explains the nature of the EROs by using high-quality models of amorphous silicon (a-Si) obtained from Monte Carlo and Molecular Dynamics simulations. The extended-range ordering in a-Si is examined through radial oscillations on the length …

An Exposition From Four-Vector To Quantum Field Theory, Weverton Dos Santos Alves

Honors Program Theses and Projects

The goal of this thesis is to research leading mass-generation theoretical models in particle physics; Which is the physics that fundamentally imparts mass on the known elementary particles. Before these mechanisms, all particles are massless quantum fields. As part of a 2021 REU (Research Experience for Undergraduates) and a team investigating quark mass at Jefferson National Lab, I worked on a mechanical design of the Lepton Direction Electromagnetic calorimeter part of the detector upgrade for the Brookhaven National Laboratory. As integral as this effort is, because the theoretical aspects of mass generation and quark mass physics are traditionally beyond what …

Generalized Langer Correction And The Exactness Of Wkb For All Conventional Potentials, Asim Gangopadhyaya, Jonathan Bougie, Constantin Rasinariu

Physics: Faculty Publications and Other Works

In this paper we investigate the exactness of the WKB quantization condition for translationally shape invariant systems. In particular, using the formalism of supersymmetric quantum mechanics, we generalize the Langer correction and show that it generates the exact quantization condition for all conventional potentials. We also prove that this correction is related to the previously proven exactness of SWKB for these potentials.

Making The Transition To Post-Quantum Cryptography, J. Simon Richard

The Downtown Review: An Interdisciplinary Journal Written and Peer-Reviewed by Mandel Honors College Students at Cleveland State University

Without intervention, quantum computing could threaten the security of a large portion of our internet in the near future. However, solutions exist. This paper, which is intended for a general audience, provides a wider context for our current state of quantum-preparedness amid the transition from classical cryptosystems to post-quantum cryptosystems—cryptographic algorithms that can resist the attacks of quantum computers. It will also submit a possible way forward inspired by the actions taken around the globe to prevent the millennium (or Y2K) bug.

Peroxisome Biogenesis Initiated By Protein Phase Separation, Zhenghao Zhang, Lydia Kisley

Faculty Scholarship

Peroxisomes are organelles that carry out β-oxidation of fatty acids and amino acids. Both rare and prevalent diseases are caused by their dysfunction. Among disease-causing variant genes are those required for protein transport into peroxisomes. The peroxisomal protein import machinery, which also shares similarities with chloroplasts, is unique in transporting folded and large, up to 10 nm in diameter, protein complexes into peroxisomes. Current models postulate a large pore formed by transmembrane proteins; however, so far, no pore structure has been observed. In the budding yeast Saccharomyces cerevisiae, the minimum transport machinery includes the membrane proteins Pex13 and Pex14 and …

Constraining The Sources Of Ultra-High-Energy Cosmic Rays Across And Above The Ankle With The Spectrum And Composition Data Measured At The Pierre Auger Observatory, A. Abdul Halim, P. Abreu, M. Aglietta, I. Allekotte, K. Almeida Cheminant, A. Almela, B. Fick, D. Nitz, Et Al.

Michigan Tech Publications, Part 1

In this work we present the interpretation of the energy spectrum and mass composition data as measured by the Pierre Auger Collaboration above 6 × 1017 eV. We use an astrophysical model with two extragalactic source populations to model the hardening of the cosmic-ray flux at around 5 × 1018 eV (the so-called "ankle" feature) as a transition between these two components. We find our data to be well reproduced if sources above the ankle emit a mixed composition with a hard spectrum and a low rigidity cutoff. The component below the ankle is required to have a very soft …