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Full-Text Articles in Physical Sciences and Mathematics

Confocal Raman Spectroscopy Coupled With In Vitro Permeation Testing To Study The Effects Of Formalin Fixation On The Skin Barrier Function Of Reconstructed Human Epidermis, Hichem Kichou, Franck Bonnier, Amanda C. Caritá, Hugh Byrne, Igor Choupra, Emilie Munnier Nov 2024

Confocal Raman Spectroscopy Coupled With In Vitro Permeation Testing To Study The Effects Of Formalin Fixation On The Skin Barrier Function Of Reconstructed Human Epidermis, Hichem Kichou, Franck Bonnier, Amanda C. Caritá, Hugh Byrne, Igor Choupra, Emilie Munnier

Articles

Confocal Raman Spectroscopy is recognised as a potent tool for molecular characterisation of biological specimens. There is a growing demand for In Vitro Permeation Tests (IVPT) in the pharmaceutical and cosmetic areas, increasingly conducted using Reconstructed Human Epidermis (RHE) skin models. In this study, chemical fixation of RHE in 10% Neutral Buffered Formalin for 24 hours has been examined for storing RHE samples at 4°C for up to 21 days. Confocal Raman Spectroscopy, combined with Principal Components Analysis, revealed the molecular-level effects of fixation, notably in protein and lipid conformation within the stratum corneum and viable epidermis. IVPT by means …


Computational And Experimental Data For Undoped And Er-Doped Lithium Tantalate Nanofluorescent Probes, Mkhitar A. Hobosyan, Andrea Pelayo Carvajal, Bhupendra B. Srivastava, Tamanna Zakia, Mohammed Jasim Uddin, Karen S. Martirosyan, Eric Rodriguez, Kofi Nketia Ackaah-Gyasi, Nicholas Dimakis Oct 2024

Computational And Experimental Data For Undoped And Er-Doped Lithium Tantalate Nanofluorescent Probes, Mkhitar A. Hobosyan, Andrea Pelayo Carvajal, Bhupendra B. Srivastava, Tamanna Zakia, Mohammed Jasim Uddin, Karen S. Martirosyan, Eric Rodriguez, Kofi Nketia Ackaah-Gyasi, Nicholas Dimakis

Physics and Astronomy Faculty Publications and Presentations

The density functional theory (DFT) and experimental data presented in this paper refer to the research article “Computational and experimental study on undoped and Er-doped lithium tantalate nano fluorescent probes”. The DFT data contain electronic and optical properties for both LiTaO3 and LiTaO3:Er+3, with Er+3 occupying either Li or Ta sites at 4.167 mol. %. All these properties were calculated at the generalized gradient approximation (GGA) limit. Additionally, electronic information was calculated using the hybrid functional by Heyd, Scuseria, and Ernzerho (HSE06), which accurately predicts the location in energy for all Er-4f orbitals. We also include simulated X-ray near edge …


First-Principles Calculations Of Thermoelectric Properties Of Fe-Based Full- Heusler Fe2cusi, Ai Nurlaela, Dwi Nanto, Anugrah Azhar, Elvan Yuniarti, Tony Kristiantoro, Dedi Dedi Sep 2024

First-Principles Calculations Of Thermoelectric Properties Of Fe-Based Full- Heusler Fe2cusi, Ai Nurlaela, Dwi Nanto, Anugrah Azhar, Elvan Yuniarti, Tony Kristiantoro, Dedi Dedi

Makara Journal of Science

A first-principle study using density functional theory (DFT) and Boltzmann transport was conducted to evaluate the thermoelectric (TE) properties of an Fe-based full-Heusler alloy. The compound studied is Fe2CuSi with a Cu2MnAl-type structure. The electronic properties of Fe2CuSi were obtained using DFT calculations by running the Quantum ESPRESSO (QE) package. By contrast, TE properties, including electron thermal conductivity, electric conductivity, and Seebeck coefficient, were computed using a semi-empirical Boltzmann transport model solved through the BoltzTraP software at 50–1,500 K temperature range. The spin-orbit coupling effect on these properties was also evaluated, demonstrating notable effects …


Optimal Radar Ranging Pulse To Resolve Two Reflectors, Andrew N. Jordan, John C. Howell, Achim Kempf, Shunxing Zhang, Derek White Sep 2024

Optimal Radar Ranging Pulse To Resolve Two Reflectors, Andrew N. Jordan, John C. Howell, Achim Kempf, Shunxing Zhang, Derek White

Mathematics, Physics, and Computer Science Faculty Articles and Research

Previous work established fundamental bounds on subwavelength resolution for the radar range resolution problem, called superradar [Phys. Rev. Appl. 20, 064046 (2023)]. In this work, we identify the optimal waveforms for distinguishing the range resolution between two reflectors of identical strength, leveraging results in quantum metrology. We discuss both the unnormalized optimal waveform as well as the best square-integrable pulse and their variants. Using orthogonal function theory, we give an explicit algorithm to optimize the wave pulse in finite time to have the best performance. We also explore range resolution estimation with unnormalized waveforms with multiparameter methods to …


Synthesis Of Zno: Zro2 Nanocomposites Using Green Method For Medical Applications, Mohammed J. Tuama, Maysoon F. Alias Sep 2024

Synthesis Of Zno: Zro2 Nanocomposites Using Green Method For Medical Applications, Mohammed J. Tuama, Maysoon F. Alias

Karbala International Journal of Modern Science

These days, nanocomposites are very popular, especially in medical applications. The spread of diseases in general, and those caused by microbes and cancerous diseases in particular, and the increased resistance of these diseases to antibiotics, have led to the need for the rapid, low-cost, and environmentally friendly production of nanocomposites. To create the chemical G-ZnO: ZrO2 and S-ZnO: ZrO2 (green technique), two different plant extracts were utilized: Z. officinal and S. aromaticum. The effective synthesis and acceptable properties features of the nanoparticles were confirmed using characterization techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) , diffuse reflectance spectroscopy …


Search For Core Collapse Supernovae Signals In Ligo’S Third Observation Run Using A Network Of Gravitational Wave Detectors Integrated With A Multiclass Convolutional Neural Network, Shahrear Khan Faisal, Gaukhar Nurbek, Michael Benjamin, Bhawana Sedhai, Soma Mukherjee Sep 2024

Search For Core Collapse Supernovae Signals In Ligo’S Third Observation Run Using A Network Of Gravitational Wave Detectors Integrated With A Multiclass Convolutional Neural Network, Shahrear Khan Faisal, Gaukhar Nurbek, Michael Benjamin, Bhawana Sedhai, Soma Mukherjee

Physics and Astronomy Faculty Publications and Presentations

In the existing body of literature, numerous waveforms of core collapse supernovae (CCSN) have emerged from extensive simulations conducted in high-performance computing facilities globally. These waveforms exhibit distinct characteristics related to their explosion mechanisms, influenced by parameters such as progenitor mass, angular momentum, gravitational wave energy, peak frequency, duration, and equation of state. Core collapse supernovae stand out as highly anticipated sources in LIGO’s fourth observation (O4) run, prompting dedicated efforts to detect them. The integration of machine learning, specifically convolutional neural networks (CNN), has become a pivotal avenue for analysis. This study addresses a fundamental query: how can a …


Systematic Review On Isolation, Purification, Characterization, And Industrial Applications Of Thermophilic Microbial Α- Amylases, Rugaiyah A. Arfah, Sarlan Sarlan, Abdul Karim, Anita Anita, Ahyar Ahmad, Paulina Taba, Harningsih Karim, Siti Halimah Larekeng, Dorothea Agnes Rampisela, Rusdina Bte Ladju Sep 2024

Systematic Review On Isolation, Purification, Characterization, And Industrial Applications Of Thermophilic Microbial Α- Amylases, Rugaiyah A. Arfah, Sarlan Sarlan, Abdul Karim, Anita Anita, Ahyar Ahmad, Paulina Taba, Harningsih Karim, Siti Halimah Larekeng, Dorothea Agnes Rampisela, Rusdina Bte Ladju

Karbala International Journal of Modern Science

The α-amylase enzyme, sourced from diverse organisms, including plants, animals, and bacteria, plays a crucial role in multiple industries, notably food processing sectors like cakes, fruit juices, and starch syrup. Research identifies thermophilic organisms as prime sources of this enzyme thriving at temperatures ranging from 41°C to 122°C. The enzyme purification was carried out using liquid-liquid extraction, which involved the exchange of substances between two liquid phases that were immiscible or partially soluble. The optimal temperature for α-amylase was 45 to 90°C. The best pH for bacterial and fungal α-amylases ranged from 5.0 to 10.5 and 5.0 to 9.0. Based …


Exploring The Early Solar System: Cometary Chemical Fingerprints: A Study Of Comet C/2022 E3 (Ztf) Via Near-Infrared Spectroscopy, Grace Puchalski Sep 2024

Exploring The Early Solar System: Cometary Chemical Fingerprints: A Study Of Comet C/2022 E3 (Ztf) Via Near-Infrared Spectroscopy, Grace Puchalski

Undergraduate Research Symposium

Comets are small, icy remnants from the solar system formation (4.5 billion years ago). Their interior composition should reflect the composition and conditions presented in the mid-plane of the protoplanetary region where (and when) they formed. These small objects predominantly reside in two major reservoirs, the Oort cloud and the Kuiper belt. Comets coming from the Oort cloud have long orbital periods while comets from the Kuiper belt have short orbital periods (< 200 years). An overarching goal in astronomy is to understand the conditions presented in the planetary region in the early solar system. Since comets lack a known mechanism of self internal heating, any processes that have changed their composition should only affect a few meters deep, which is believed to be excavated over a course of a perihelion passage into the inner parts of the solar system. As comets get closer to the Sun, solar irradiation causes their ices to sublime, leaving a formation of a freely expanding atmosphere (coma). Depending on the science interest, astrophysicists use different techniques for data collection, a common one being spectroscopy. Using iSHELL spectrograph at the NASA-Near-Infrared Telescope Facility (IRTF), we examine the primary chemical composition (e.g., H2O, CO, CH4, C2H6, C2H2, H2CO, NH3, CH3OH, OCS, and OH) of cometary coma in bright comet C/2022 E3 (ZTF). Our preliminary results indicate the H2O production rate of ~3.4E28 (molecules per second), which corresponds to the rotational temperature of 86 (K). Cometary atmospheres are dense enough that molecules in the inner coma are thermalized by collision (Local Thermodynamic Equilibrium), thus 86 (K) is a physical parameter of coma. We compared the production of the rest of species with that of water (in %) and our results indicated that comet E3 was typical (close to average) in mixing ratios of all volatile species. By mapping the intensity of light with distance from the nucleus,we were able to examine the spatial distribution of volatiles and dust in E3’s coma which were consistent with production directly from the nucleus.


The Effect Of Different Vegetable Oils (Macadamia Nut Oil And Walnut Oil) On The Coefficient Of Friction As A Finish For Oak Wood, Lee Dillon Sep 2024

The Effect Of Different Vegetable Oils (Macadamia Nut Oil And Walnut Oil) On The Coefficient Of Friction As A Finish For Oak Wood, Lee Dillon

Journal of the South Carolina Academy of Science

Slipping due to insufficient friction with flooring can cause fatal injuries in workplaces and homes. Oak wood flooring is commonly used in construction to build these environments. In the manufacturing process, wood finishing is conducted at the end of the process to strengthen the properties and longevity of the wood, although it could impact the coefficient of friction (COF) causing slip falls. Vegetable oils, such as macadamia nut and walnut oils, used as wood finishes have gained prominence due to their beneficial aspects to the environment. However, little is known about their effectiveness as a safe coating for wood floors. …


Table Of Contents Sep 2024

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Implementing Reactivity In Molecular Dynamics Simulations With Harmonic Force Fields, Jordan J. Winetrout, Krishan Kanhaiya, Josh Kemppainen, Pieter J. In ‘T Veld, Geeta Sachdeva, Ravindra Pandey, Behzad Damirchi, Adri Van Duin, Gregory Odegard, Hendrik Heinz Sep 2024

Implementing Reactivity In Molecular Dynamics Simulations With Harmonic Force Fields, Jordan J. Winetrout, Krishan Kanhaiya, Josh Kemppainen, Pieter J. In ‘T Veld, Geeta Sachdeva, Ravindra Pandey, Behzad Damirchi, Adri Van Duin, Gregory Odegard, Hendrik Heinz

Michigan Tech Publications, Part 2

The simulation of chemical reactions and mechanical properties including failure from atoms to the micrometer scale remains a longstanding challenge in chemistry and materials science. Bottlenecks include computational feasibility, reliability, and cost. We introduce a method for reactive molecular dynamics simulations using a clean replacement of non-reactive classical harmonic bond potentials with reactive, energy-conserving Morse potentials, called the Reactive INTERFACE Force Field (IFF-R). IFF-R is compatible with force fields for organic and inorganic compounds such as IFF, CHARMM, PCFF, OPLS-AA, and AMBER. Bond dissociation is enabled by three interpretable Morse parameters per bond type and zero energy upon disconnect. Use …


Angular Momentum Flow Without Anything Carrying It, Yakir Aharonov, Daniel Collins, Sandu Popescu Sep 2024

Angular Momentum Flow Without Anything Carrying It, Yakir Aharonov, Daniel Collins, Sandu Popescu

Mathematics, Physics, and Computer Science Faculty Articles and Research

Transfer of conserved quantities between two remote regions is generally assumed to be a rather trivial process: a flux of particles carrying the conserved quantities propagates from one region to another. However, we demonstrate a flow of angular momentum from one region to another across a region of space in which there is a vanishingly small probability of any particles (or fields) being present. This shows that the usual view of how conservation laws work needs to be revisited.


Performance Of The Hawc Observatory And Tev Gamma-Ray Measurements Of The Crab Nebula With Improved Extensive Air Shower Reconstruction Algorithms, A. Albert, R. Alfaro, C. Alvarez, A. Andrés, J. C. Arteaga-Velázquez, D. Avila Rojas, S. Groetsch, P. Hüntemeyer, R. Turner, X. Wang, Et Al. Sep 2024

Performance Of The Hawc Observatory And Tev Gamma-Ray Measurements Of The Crab Nebula With Improved Extensive Air Shower Reconstruction Algorithms, A. Albert, R. Alfaro, C. Alvarez, A. Andrés, J. C. Arteaga-Velázquez, D. Avila Rojas, S. Groetsch, P. Hüntemeyer, R. Turner, X. Wang, Et Al.

Michigan Tech Publications, Part 2

The High-Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory, located on the side of the Sierra Negra volcano in Mexico, has been fully operational since 2015. The HAWC collaboration has recently significantly improved their extensive air shower reconstruction algorithms, which has notably advanced the observatory performance. The energy resolution for primary gamma rays with energies below 1 TeV was improved by including a noise-suppression algorithm. Corrections have also been made to systematic errors in direction fitting related to the detector and shower plane inclinations, O ( 0 .° 1 ) biases in highly inclined showers, and enhancements to the core reconstruction. The …


Striatal Beat Frequency Interval Timing Model With Microgravity Stressor, Jason Michael Fitzgerald, Sorinel Oprisan Sep 2024

Striatal Beat Frequency Interval Timing Model With Microgravity Stressor, Jason Michael Fitzgerald, Sorinel Oprisan

Journal of the South Carolina Academy of Science

The Striatal Beat Frequency (SBF) model of interval timing uses frontal cortex (FC) neural oscillations to record the state of the brain at the reinforcement time Tc during fixed interval (FI) procedures in the long-term memory (LMEM). The state of the FC oscillators at any given time is stored in a short-term memory (SMEM) buffer. The SBF model uses the spiny neurons of the basal ganglia (BG) as coincidence detectors to produce beats between the content of the SMEM and LMEM. Across multiple species that can perform interval timing, there are two invariant properties: (a) the timing is precise, and …


Luminescent Coupling In Perovskite Tandem Solar Cells: The Advantages Of Perovskite And Luminescent Coupling In Photovoltaics, Briana Dokken Sep 2024

Luminescent Coupling In Perovskite Tandem Solar Cells: The Advantages Of Perovskite And Luminescent Coupling In Photovoltaics, Briana Dokken

Senior Seminars and Capstones

Multijunction or tandem solar cells are made of multiple semiconductor light absorbing layers. Having multiple absorber layers in a solar cell allows it to absorb a larger range of the solar spectrum. When electrons recombine (relax to a lower energy state) in the top layer of a tandem solar cell, they can emit luminescent photons that are absorbed by the bottom layer of the cell. This process is called luminescent coupling, and it can be used to enhance the performance of photovoltaic cells. Another strategy to increase solar cell performance is to use perovskite as the absorber layer material. Currently, …


Toi–757 B: An Eccentric Transiting Mini–Neptune On A 17.5–D Orbit, A Alqasim, N Grieves, N M. Rosário, D Gandolfi, J H. Livingston, S Sousa, K A. Collins, J K. Teske, M Fridlund, Ryan J. Oelkers Sep 2024

Toi–757 B: An Eccentric Transiting Mini–Neptune On A 17.5–D Orbit, A Alqasim, N Grieves, N M. Rosário, D Gandolfi, J H. Livingston, S Sousa, K A. Collins, J K. Teske, M Fridlund, Ryan J. Oelkers

Physics and Astronomy Faculty Publications and Presentations

We report the spectroscopic confirmation and fundamental properties of TOI 757 b, a mini Neptune on a 17.5 d orbit transiting a bright star (⁠ mag) discovered by the TESS mission. We acquired high precision radial velocity measurements with the HARPS, ESPRESSO, and PFS spectrographs to confirm the planet detection and determine its mass. We also acquired space borne transit photometry with the CHEOPS space telescope to place stronger constraints on the planet radius, supported with ground based LCOGT photometry. WASP and KELT photometry were used to help constrain the stellar rotation period. We also determined the fundamental parameters of …


Twisted Spatiotemporal Optical Vortex Beams In Dispersive Media, Milo W. Hyde Iv Sep 2024

Twisted Spatiotemporal Optical Vortex Beams In Dispersive Media, Milo W. Hyde Iv

Faculty Publications

We derive a closed-form expression for the mutual coherence function (MCF) of a twisted spatiotemporal optical vortex (STOV) beam after propagating a distance in a linear dispersive medium. A twisted STOV beam is a partially coherent optical field that possesses a coherent STOV and a stochastic twist coupling its space and time dimensions. These beams belong to a special class of space–time-coupled light fields that carry transverse (to the direction of propagation) orbital angular momentum, making them potentially useful in numerous applications including quantum optics, optical manipulation, and optical communications. After presenting the derivation, we validate our new general MCF …


Shear Viscosity Of Quasi One-Dimensional Bec Tubes And Entanglement Negativity Conditions, Camilla Polvara Sep 2024

Shear Viscosity Of Quasi One-Dimensional Bec Tubes And Entanglement Negativity Conditions, Camilla Polvara

Dissertations, Theses, and Capstone Projects

Shear Viscosity of Quasi One-dimensional BEC Tubes

We consider layered Bose-Einstein condensates interacting via contact intra-condensate interacions and dipolar inter-condensate potentials, both of which dominate intercondensate tunneling (which we neglect for simplicity). For this system, we compute the normal modes, we study its localization properties by numerically computing the inverse participation ratio, and we compute the inter-tube shear viscosity.

Entanglement Negativity Conditions

This project explores bounds on entanglement negativity using operator inequalities, building on the results of [1]. We are looking for a way to quantify entanglement, as an alternative to calculating the full negativity, which would otherwise require the …


Interplay Of Magnetic Impurities And Superconductivity In Topological Materials, Didier Ndengeyintwali Sep 2024

Interplay Of Magnetic Impurities And Superconductivity In Topological Materials, Didier Ndengeyintwali

Dissertations, Theses, and Capstone Projects

The interplay of superconductivity and magnetism has been a long-standing topic of interest since the discovery of superconductivity. In recent years it has been shown that topological superconductivity, which has promising applications such as in topological quantum computing, could result from such interplay. Motivated by the later results I study the effect of magnetic impurities in superconducting doped topological insulators, such as Iron based topological superconductors. I show that topological character of parent materials could lead to modifications in the structure of magnetic impurity induced in-gap states. Moreover, the superconductivity induced interaction between magnetic impurities in doped topological insulator would …


Antioxidant, Photoprotective, And Cytotoxic Activities Of Tristaniopsis Merguensis Leaf Fractions With Molecular Docking Study Of Potential Fraction, Boima Situmeang, Respati Tri Swasono, Tri Joko Raharjo Aug 2024

Antioxidant, Photoprotective, And Cytotoxic Activities Of Tristaniopsis Merguensis Leaf Fractions With Molecular Docking Study Of Potential Fraction, Boima Situmeang, Respati Tri Swasono, Tri Joko Raharjo

Karbala International Journal of Modern Science

Through experimental along with molecular docking techniques of potential fraction, this study intended to evaluate the essential phytochemical elements of Tristaniopsis merguensis leaflets as well as potential antioxidant, photoprotective, along with cytotoxic activities. The DPPH and ABTS tests were used to evaluate the antioxidant efficacy of the n-hexane (HPF), ethyl acetate (EPF), and methanol (MPF) fractions. Using an in-vitro solar protection factor (SPF) assessment, the photoprotective ability of T. merguensis components against UV damage was examined. Subsequently, invitro cytotoxic research were carried out against MCF-7 cell line (breast cancer line) assay. This was followed by molecular docking stimulation testing against …


Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The Third Observing Run Of Advanced Ligo And Advanced Virgo, Marek J. Szczepańczyk, Yanyan Zheng, Javier M. Antelis, Michael G. Benjamin, Marie-Anne Bizouard, Alejandro Casallas-Lagos, Pablo Cerda-Duran, Derek Davis, Dorota Gondek-Rosinska, Soma Mukherjee Aug 2024

Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The Third Observing Run Of Advanced Ligo And Advanced Virgo, Marek J. Szczepańczyk, Yanyan Zheng, Javier M. Antelis, Michael G. Benjamin, Marie-Anne Bizouard, Alejandro Casallas-Lagos, Pablo Cerda-Duran, Derek Davis, Dorota Gondek-Rosinska, Soma Mukherjee

Physics and Astronomy Faculty Publications and Presentations

We present the results from a search for gravitational-wave transients associated with core-collapse supernovae observed optically within 30 Mpc during the third observing run of Advanced LIGO and Advanced Virgo. No gravitational wave associated with a core-collapse supernova has been identified. We then report the detection efficiency for a variety of possible gravitational-wave emissions. For neutrino-driven explosions, the distance at which we reach 50% detection efficiency is up to 8.9 kpc, while more energetic magnetorotationally driven explosions are detectable at larger distances. The distance reaches for selected models of the black hole formation, and quantum chromodynamics phase transition are also …


Experimental Realization Of Supergrowing Fields, Sethuraj K. R., Tathagata Karmakar, S. A. Wadood, Andrew N. Jordan, A. Nick Vamivakas Aug 2024

Experimental Realization Of Supergrowing Fields, Sethuraj K. R., Tathagata Karmakar, S. A. Wadood, Andrew N. Jordan, A. Nick Vamivakas

Mathematics, Physics, and Computer Science Faculty Articles and Research

Supergrowth refers to the local amplitude growth rate of a signal being faster than its fastest Fourier mode. In contrast, superoscillation pertains to the variation of the phase. Compared to the latter, supergrowth can have exponentially higher intensities and promises improvement over superoscillation-based superresolution imaging. Here, we demonstrate the experimental synthesis of controlled supergrowing fields with a maximum growth rate of ∼19.07 times the system bandlimit. Our work is an essential step toward realizing supergrowth-based far-field superresolution imaging.


Open Quantum Systems In High Energy Physics, Bharath Sambasivam Aug 2024

Open Quantum Systems In High Energy Physics, Bharath Sambasivam

Dissertations - ALL

Open quantum systems (OQS) are ubiquitous in various fields of physics, such as high energy physics, cosmology, atomic and molecular physics, and quantum optics. In some cases, there is a natural separation between the system and the environment, like the presence of a horizon in inflationary cosmology. In other cases, like field theories coupled to thermal baths or at finite chemical potential, it is not practical to simulate the large number of degrees of freedom making up the bath. The system of interest can be described by an effective theory upon integrating out the environment degrees of freedom. In certain …


Studies Towards Improved Gravitational Wave Detector Thermodynamics, Daniel Vander-Hyde Aug 2024

Studies Towards Improved Gravitational Wave Detector Thermodynamics, Daniel Vander-Hyde

Dissertations - ALL

Since the first gravitational wave detection, the Laser Interferometric Gravitational Wave Observatories (LIGO) combined with an expanding and co-observing global gravitational wave network (i.e. Virgo, KAGRA) has worked to increase a novel and growing astronomical data catalog of gravitational wave detections. With each additional observing run, rates of detection continue to increase with iterative upgrades to detector technology. Discussed within this thesis are considerations pertinent to the improvement of Dual Recycled Fabry-Perot Michelson interferometer (DRFPMI) thermodynamics proposed during LIGO's third observing run (O3) for present and future detectors. The first chapter reviews fundamental material relevant to gravitational waves and how …


Open-Loop Wavefront Sensing In The Presence Of Speckle And Weak Scintillation, Derek J. Burrell, Mark F. Spencer, Ronald G. Driggers Aug 2024

Open-Loop Wavefront Sensing In The Presence Of Speckle And Weak Scintillation, Derek J. Burrell, Mark F. Spencer, Ronald G. Driggers

Faculty Publications

In this paper, we show that speckle averaging helps to reduce the measurement error associated with a Shack–Hartmann wavefront sensor (SHWFS); however, this reduction is rendered ineffective with increasing beacon anisoplanatism. We do so operating in a weak-scintillation regime, where the SHWFS offers robust performance, and using in-plane translation of the illuminated rough surface to accomplish frame-to-frame speckle diversity. Understanding these trade-space limitations is critical when performing wavefront sensing with noncooperative, extended-source beacons.


Quantum Field Theory And The Limits Of Reductionism, Emily Adlam Aug 2024

Quantum Field Theory And The Limits Of Reductionism, Emily Adlam

Mathematics, Physics, and Computer Science Faculty Articles and Research

I suggest that the current situation in quantum field theory (QFT) provides some reason to question the universal validity of ontological reductionism. I argue that the renormalization group flow is reversible except at fixed points, which makes the relation between large and small distance scales quite symmetric in QFT, opening up at least the technical possibility of a non-reductionist approach to QFT. I suggest that some conceptual problems encountered within QFT may potentially be mitigated by moving to an alternative picture in which it is no longer the case that the large supervenes on the small. Finally, I explore some …


Unraveling The Structure And Star Formation History Of Polar Ring Galaxies, Kyle Lackey Aug 2024

Unraveling The Structure And Star Formation History Of Polar Ring Galaxies, Kyle Lackey

Theses and Dissertations

Polar ring galaxies (PRGs) are a fascinating subgroup of early-type galaxies (ETGs) consisting of a central host galaxy - typically E/S0 - surrounded by a ring of gas, dust and stars orbitting perpedicular to the major axis of that host. In order to estimate physical properties and origins of five such objects taken from Whitmore's 1990 PRC catalog, we conduct a photometric study in optical and infrared wavebands. Data are taken from SDSS, GMOS-S, HST-WFPC2, and SST-IRAC. Each object was decomposed into a host galaxy bulge, host galaxy disk, and polar ring, and each component was fit with a Sersic …


Exiting Inflation With A Smooth Scale Factor, Harry Oslislo Aug 2024

Exiting Inflation With A Smooth Scale Factor, Harry Oslislo

Theses and Dissertations

The expectation that the physical expansion of space occurs smoothly may be expressed mathematically as a requirement for continuity in the time derivative of the metric scale factor of the Friedmann–Robertson–Walker cosmology. We explore the consequences of imposing such a smoothness requirement, examining the forms of possible interpolating functions between the end of inflation and subsequent radiation- or matter-dominated eras, using a straightforward geometric model of the interpolating behavior. We quantify the magnitude of the cusp found in a direct transition from the end of slow roll inflation to the subsequent era, analyze the validity several smooth interpolator candidates, and …


On Magnetic Moments Of Up And Down Quarks And Electron Neutrino Structures Composed Of Fractional Charges, Polievkt Perov Aug 2024

On Magnetic Moments Of Up And Down Quarks And Electron Neutrino Structures Composed Of Fractional Charges, Polievkt Perov

College of Arts & Sciences Faculty Works

Abstract

Using our models of elementary particles as spinning structures composed of fractional +-e/3 charges, we suggest a possible mechanism of the inverse-b reaction as the transfer of one +e/3 charge from its axial position in the antineutrino to the axial position in an up-quark of a proton. Such a transfer converts that up-quark into a positron, and the antineutrino becomes a down-quark after one of the antineutrino’s axial positive charges is removed from it. We will consider that a positron is a tetrahedral-like structure with three positive basic charges revolve about the axis passing through the fourth positive …


Breaking The Causality Limit For Broadband Acoustic Absorption Using A Noncausal Active Absorber, Kangkang Wang, Sipei Zhao, Chen Shen, Haishan Zou, Jing Lu, Andrea Alu Aug 2024

Breaking The Causality Limit For Broadband Acoustic Absorption Using A Noncausal Active Absorber, Kangkang Wang, Sipei Zhao, Chen Shen, Haishan Zou, Jing Lu, Andrea Alu

Henry M. Rowan College of Engineering Departmental Research

The principle of causality imposes a constraint between the thickness and bandwidth of absorbers. This trade-off applies to any linear, time-invariant, passive system, limiting the development of broadband-absorbing materials that demand a thin profile for sound, light, and radio waves. Here, we demonstrate a strategy to overcome this constraint in acoustics using a noncausal active absorber whose response is controlled over time. A theoretical framework is established, which sets a relation among minimum thickness, bandwidth, and a priori information about the incident signal, representing a relaxed physical bound for noncausal absorbers. We design an absorber based on this principle and …