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Searching For Temporal Variations In The Fine-Structure Constant Using Espresso Spectrograph Data, David Hoffman IV 2026 University of South Carolina - Columbia

Searching For Temporal Variations In The Fine-Structure Constant Using Espresso Spectrograph Data, David Hoffman Iv

Senior Theses

The fine-structure constant α is a dimensionless constant, defined as e²/(4πε₀ℏc) ≈ 1/137. On the order of human timescales, its value is very much unchanging, however, in recent years there has been extensive debate over whether or not the value of α has remained constant over cosmological timescales. With the natural corollary to a changing α being that either one or multiple of its constituent physical constants have also changed in value, observing a variation in the fine-structure constant would have vast ramifications for our understanding of the nature of the early universe and how it has evolved. While past …


Construction Of A Deffi Sprayer: Using 3d Printer Methodology And Techniques For Cost-Effective Analysis Using Desi Mass Spectrometry Imaging, Ryan Karst, Savvy Stevens, Luke Amos, Logan Koester, Ethan Newbold, Karson Whitaker 2026 Indiana State University

Construction Of A Deffi Sprayer: Using 3d Printer Methodology And Techniques For Cost-Effective Analysis Using Desi Mass Spectrometry Imaging, Ryan Karst, Savvy Stevens, Luke Amos, Logan Koester, Ethan Newbold, Karson Whitaker

Symposium Projects

Using 3D Printer Methodology and Techniques for Cost-Effective Analysis using DESI Mass Spectrometry Imaging


The Eye: A Science-Fiction Screenplay Examining Space-Time, Meteorology, And Human Connection, Ella K. Lukowiak 2026 University of South Carolina

The Eye: A Science-Fiction Screenplay Examining Space-Time, Meteorology, And Human Connection, Ella K. Lukowiak

Senior Theses

This thesis explores the nature of time, meteorology, and human interconnection to the universe through the lens of a science-fiction screenplay. The creative project spans a three-act, detailed outline, and a screenplay draft of Act I. It is based upon extensive scientific research regarding hurricane development, the inner workings of organizations such as the National Weather Service, Einstein’s Theory of Relativity, and the space-time continuum. I will delve into the various factors that shaped my science-fiction premise, including pivotal films such as Christopher Nolan’s INTERSTELLAR (2014) and Denis Villeneuve’s ARRIVAL (2016). Both of these filmmakers integrated complex science-fiction concepts into …


Information Theory Analysis Of The Solar Wind Magnetic Structures For Space Weather Prediction, Katherine Holland 2026 Embry-Riddle Aeronautical University

Information Theory Analysis Of The Solar Wind Magnetic Structures For Space Weather Prediction, Katherine Holland

Doctoral Dissertations and Master's Theses

Forecasting space weather at Earth is highly complicated, because of the limited measurements of the dynamic processes in the Sun that span multiple temporal, spatial, and energy-scales. The solar wind is a highly structured, multi-scale, evolving plasma and consists of coronal mass ejections (CMEs), stream interaction regions (SIRs), expanding flux tubes (Borovsky, 2008), and interplanetary magnetic field (IMF) discontinuities and fluctuations. The aim of this research is to improve our understanding of the evolution and dissipation of different scale-size solar wind magnetic structures as they move from the Sun-Earth Lagrange point 1 (L1) to Earth's bow shock and, ultimately, to …


Non-Hermitian Sl (3, C) Three-Mode Couplers, B. M. Rodríguez-Lara, Hamed Ghaemi-Dizicheh, Shahram Dehdashti, Andreas Hanke, Ahmed Touhami, J. Nötzel 2026 The University of Texas Rio Grande Valley

Non-Hermitian Sl (3, C) Three-Mode Couplers, B. M. Rodríguez-Lara, Hamed Ghaemi-Dizicheh, Shahram Dehdashti, Andreas Hanke, Ahmed Touhami, J. Nötzel

Physics & Astronomy Faculty Publications

Photonic systems with exceptional points, where eigenvalues and corresponding eigenstates coalesce, have attracted interest due to their topological features and enhanced sensitivity to external perturbations. Non-Hermitian mode-coupling matrices provide a tractable analytic framework to model gain, loss, and chirality across optical, electronic, and mechanical platforms without the complexity of full open-system dynamics. Exceptional points define their spectral topology, and enable applications in mode control, amplification, and sensing. Yet N -mode couplers, the minimal setting for N th-order exceptional points, are often studied in specific designs that overlook their algebraic structure. We introduce a general sl(N , C) framework for arbitrary …


Strong Gravitational Lensing Of Balart-Vagenas Regular Black Holes, Akif Pervez, Hassan Moin Ud Din, Handika Satrio Ramdhan 2026 Department of Physic, Universitas Indonesia, Depok 16424, Indonesia

Strong Gravitational Lensing Of Balart-Vagenas Regular Black Holes, Akif Pervez, Hassan Moin Ud Din, Handika Satrio Ramdhan

Makara Journal of Science

Gravitational lensing is an integral part of Einstein general theory of relativity. The existence of singularity in standard black holes is a hurdle for understanding the properties of black holes. The introduction of nonlinear electrodynamics (NLED) offers an intriguing possibility of constructing non-singular black hole. Gravitational lensing by the photon sphere probes the physical properties of lens objects such as black holes. This work presents a strong deflection limit analysis in a general asymptotically flat, stationary, spherically symmetric spacetime. We extend the analysis of the light deflection around the photon sphere-complete capture, and set a strong field limit that is …


A Study Of Transients From Ground-Based Surveys Reveals New Ultra-Compact Accreting White Dwarf Binaries, Jan Kára, Liliana E. Rivera Sandoval, Wendy Mendoza, Thomas J. Maccarone, Manuel Pichardo Marcano, Luis Salazar Manzano, Ryan J. Oelkers, Jan van Roestel 2026 The University of Texas Rio Grande Valley

A Study Of Transients From Ground-Based Surveys Reveals New Ultra-Compact Accreting White Dwarf Binaries, Jan Kára, Liliana E. Rivera Sandoval, Wendy Mendoza, Thomas J. Maccarone, Manuel Pichardo Marcano, Luis Salazar Manzano, Ryan J. Oelkers, Jan Van Roestel

Physics & Astronomy Faculty Publications

AM CVn stars are ultra-compact semi-detached binaries consisting of a white dwarf primary and a hydrogen-depleted secondary. In this paper, we present spectroscopic and photometric results of 15 transient sources pre-classified as AM CVn candidates. Our analysis confirms 9 systems of the type AM CVn, 3 hydrogen-rich cataclysmic variables (accreting white dwarfs with near-main-sequence stars for donors), and 3 systems that could be evolved cataclysmic variables. Eight of the AM CVn stars are analysed spectroscopically for the first time, which increases the number of spectroscopically confirmed AM CVns by about 10%. TESS data revealed the orbital period of the AM …


First-Order Axial Perturbation Of The Reissner–Nordström Metric Against A Possible Parity-Violating Gravity Background, Abhishek Rout, Brett David Altschul 2026 University of South Carolina

First-Order Axial Perturbation Of The Reissner–Nordström Metric Against A Possible Parity-Violating Gravity Background, Abhishek Rout, Brett David Altschul

Faculty Publications

We study axial perturbations of Reissner–Nordström black holes within the general frame-work of parity-violating modified gravity theories. We derive the governing equations for a class of frame-dragging perturbations, focusing on the symmetry structure and radial dependence of the perturbed metric component, describing its behavior across three distinct regions: near the singularity (r → 0), between the inner and outer Reissner–Nordström horizons (r− < r < r+), and in the asymptotic exterior regime (r → ∞). Using a combination of analytical and numerical methods, we analyze the solutions for varying black hole charge-to-mass ratios (Q/M) and angular momentum parameters (l). Key findings include the suppression of perturbations by the electromagnetic field for higher Q/M; the emergence of radial resonance-like behavior for specific l values; and a high degree of symmetry for solutions in the extremal limit (Q/M ∼ 1), attributed to the AdS2 × S 2 near-horizon geometry. The WKB approximation is employed to study the high-l regime, revealing quantized radial resonance modes and singular behavior in the extremal limit. Additionally, we explore the role of boundary conditions and the possibility of a Chern–Simons field Θ as the source of the parity violation, showing that consistency and the behavior of the perturbations under time reversal demand a constant field (and thus no actually observable Chern–Simons effects) at leading order. These results provide a basis for further analysis of the stability and dynamical properties of charged black holes in parity-violating theories, with potential experimental signatures in gravitational wave observations.


Bacillus Subtilis Parb C-Terminal Lysine Residues Are Essential For Dimerization And In Vivo Function, Indicating Their Roles In Dna Sliding, Aleksey Aleshintsev, Lindsey E. Way, Ngoc Khanh Lai, Bianca Guerra, Paloma Dorantes, Lois Akosua Serwaa, Sealtiel Anulao, Miranda Molina, Xindan Wang, HyeongJun Kim 2026 The University of Texas Rio Grande Valley

Bacillus Subtilis Parb C-Terminal Lysine Residues Are Essential For Dimerization And In Vivo Function, Indicating Their Roles In Dna Sliding, Aleksey Aleshintsev, Lindsey E. Way, Ngoc Khanh Lai, Bianca Guerra, Paloma Dorantes, Lois Akosua Serwaa, Sealtiel Anulao, Miranda Molina, Xindan Wang, Hyeongjun Kim

Physics & Astronomy Faculty Publications

The broadly conserved ParB protein performs crucial functions in bacterial chromosome segregation and replication regulation. The cellular function of ParB requires it to dimerize, recognize parS DNA sequences, clamp on DNA, then slide to adjacent sequences through nonspecific DNA binding. How ParB coordinates nonspecific DNA binding and sliding remains elusive. Here, we combine multiple in vitro biophysical and computational tools and in vivo approaches to address this question. We found that five conserved lysine residues in the C-terminal domain (CTD) of ParB play distinct roles. While the two central rigid lysine residues provide the structural platform for the CTD, the …


Galaxy Zoo: A Catalog Of ~1000 Occulting Pairs In The Desi Legacy Survey For Dust Studies, Trevor A. Butrum, Benne Holwerda 2026 University of Louisville

Galaxy Zoo: A Catalog Of ~1000 Occulting Pairs In The Desi Legacy Survey For Dust Studies, Trevor A. Butrum, Benne Holwerda

The Cardinal Edge

Occulting pairs of galaxies, where a foreground galaxy partially overlaps a background galaxy, are becoming increasingly valuable for studying dust attenuation and other dust properties in galaxies. These occulting systems present a unique opportunity to derive attenuation measurements by modelling the light from both galaxies and inferring the missing light in the overlapping regions, leaving only the light attenuated by dust remaining. However, the current master catalogue of these pairs is still relatively limited in number, and expanding such a catalogue will provide significant advantages. To achieve this, we use galaxies classified as "overlapping" from Galaxy Zoo DECaLS (GZD-1, 2, …


High Polarization In Narrow Line Seyfert 1 Galaxy Iras 1239.7+3333, Bryn Connelly, Dirk Grupe PhD 2026 University of Louisville

High Polarization In Narrow Line Seyfert 1 Galaxy Iras 1239.7+3333, Bryn Connelly, Dirk Grupe Phd

The Cardinal Edge

IRAS 1239 is a narrow line Seyfert 1 galaxy discovered with the ROSAT All-Sky survey. It is interesting because it shows very high polarization, but very little cold X-ray absorption, potentially revealing more insight into the classification of Seyfert galaxies. An Active Galactic Nucleus, or AGN, is an accreting black hole at the center of a galaxy. Galaxies containing these AGNs are known as active galaxies. There are several different types of active galaxies, including Seyfert galaxies. These are a common galaxy type, making up around 10% of galaxies. They are classified by having strong emission lines and detectable host …


Empirical Validation Of Einstein’S Coefficient For The Deflection Of Light Due To Gravitational Forces, Alexandra R. McDowell 2026 Murray State University

Empirical Validation Of Einstein’S Coefficient For The Deflection Of Light Due To Gravitational Forces, Alexandra R. Mcdowell

Honors College Theses

Einstein’s formula to calculate the deflection angle of light through space as it interacts with gravity was introduced in his 1916 publication on general relativity. This was not a new idea, but his equation was, and it was correct. Just 3 years after this publication, it was empirically validated by Sir Arthur Eddington and Sir Frank Dyson. Since that experiment in 1919, at least seven others have been performed that also gave definitive answers in support of Einstein’s deflection constant of 1.751 arcseconds. The two most recent ones made groundbreaking contributions to this effort. The 2017 eclipse showed reproducible results …


New Avenues For |Δb=2| Processes Beyond Neutron-Antineutron Oscillations, Arnau Basi Beneito, Svjetlana Fajfer, Alexey A. Petrov 2026 University of South Carolina

New Avenues For |Δb=2| Processes Beyond Neutron-Antineutron Oscillations, Arnau Basi Beneito, Svjetlana Fajfer, Alexey A. Petrov

Faculty Publications

We explore baryon-number-violating (|∆B| = 2) processes beyond the well-known neutron-antineutron (n-n̄) oscillations, focusing on the Λ-Λ̄ system. The presence of a strange quark in the Λ baryon introduces a new set of six-quark operators roughly of the form (uds)2, which are different from the (udd)2 operators responsible for n-n̄ oscillations. Using the Standard Model Effective Field Theory (SMEFT), we classify all dimension-9 operators that cause |∆B| = 2  transitions and study their UV completions mediated by exotic scalar fields with trilinear interactions. We demonstrate that …


Using Ngc 2168 To Calibrate Ages For Individual Stars, Skylar G. Butler 2026 Embry-Riddle Aeronautical University

Using Ngc 2168 To Calibrate Ages For Individual Stars, Skylar G. Butler

Beyond: Undergraduate Research Journal

This research investigates the precision and accuracy of age determination in open star clusters using BASE-9 software. The project is divided into two parts, with the first being the determination of the age of the entire cluster and the second being the age determination of the individual stars within the NGC 2168 cluster. Part one involves analyzing the collective properties of the cluster to derive its age. Part two involves assessing the age of individual stars within the selected star clusters using BASE-9 software. We will evaluate the reliability and validity of the age determinations obtained by analyzing individual stars …


Coordinates, Time, And The Sky, John R. Thorstensen 2026 Dartmouth College

Coordinates, Time, And The Sky, John R. Thorstensen

Other Faculty Materials

This monograph explains celestial coordinates and their basis in the motion and orientation of the earth.  It was written for use in undergraduate classes in basic astronomy and observational techniques.


Spectroscopy And Photochemistry Of The Astrochemical Molecules Sicp And Alcp, Vincent J. Esposito, Tarek Trabelsi, Rebecca Firth, Ryan C. Fortenberry, Joseph S. Francisco 2026 Chapman University

Spectroscopy And Photochemistry Of The Astrochemical Molecules Sicp And Alcp, Vincent J. Esposito, Tarek Trabelsi, Rebecca Firth, Ryan C. Fortenberry, Joseph S. Francisco

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Through characterization of the electronic excited-state topology, linear-SiCP is predicted to be photostable in the UV region, whereas linear-AlCP is predicted to undergo photodissociation to form Al+CP products after absorption of light in the 200–250 nm range, representing a catalytic process for freeing aluminum molecules from a solid dust grain. Both SiCP and AlCP are predicted to have electronic transitions with large absorption cross sections (∼10–17 cm2) and to undergo fluorescence from bound excited states. The total electronic absorption spectrum is provided to inform electronic spectroscopy experiments. Silicon (SiC) and aluminum (Al2O3) dust …


Complex Spin Structure In Co-Trimer-Chain Li2Co3Se4O12, Jie Xing, Feng Ye, Daniel Duong, Sai Mu, Max T. Pan, Rongying Jin 2026 University of South Carolina

Complex Spin Structure In Co-Trimer-Chain Li2Co3Se4O12, Jie Xing, Feng Ye, Daniel Duong, Sai Mu, Max T. Pan, Rongying Jin

Faculty Publications

Complex magnetic materials are extremely attractive for revealing unconventional spin states and novel magnetic excitations. Here, we report the structural, thermodynamic, and magnetic properties of a novel magnetic material Li2Co3Se4O12based on x-ray and neutron diffraction, specific heat, magnetization, and x-ray photoelectron spectroscopy measurements. X-ray and neutron diffraction refinements reveal two Co sites Co (1) and Co (2) even though both are in the octahedral environment. While they are not connected along the b and c directions, these octahedra are edge-shared forming the Co (2) – Co (1) – Co (2) trimer chain …


X-Ray Emission In Illustristng Circum-Cluster Environments: Ii. Possible Origins Of The Soft X-Ray Excess Emission, Celine Gouin, Daniela Galárraga-Espinosa, Massimiliano Bonamente, Stephen Walker, Mohammad Mirakhor, Richard Lieu, Clotilde Laigle, Etienne Bonnassieux, Charlotte Welker, Stefano Gallo, Tony Bonnaire, Jade Paste 2026 Sorbonne Université

X-Ray Emission In Illustristng Circum-Cluster Environments: Ii. Possible Origins Of The Soft X-Ray Excess Emission, Celine Gouin, Daniela Galárraga-Espinosa, Massimiliano Bonamente, Stephen Walker, Mohammad Mirakhor, Richard Lieu, Clotilde Laigle, Etienne Bonnassieux, Charlotte Welker, Stefano Gallo, Tony Bonnaire, Jade Paste

Publications and Research

Context. An excess of soft X–ray emission (∼0.2 − 1 keV) above the contribution from the hot intracluster medium (ICM) has been detected in a number of galaxy clusters, including the Coma cluster. The physical origin of this emitting medium above the hot ICM has not yet been determined, in particular, it is unclear whether it is thermal or nonthermal.

Aims. We investigate the gas phase and gas structure that reproduce the soft excess radiation from the cluster core to the outskirts best using simulations.

Method. By using the IllustrisTNG simulation (TNG300), we predict the radial profile of thermodynamic properties …


Egain Tube Memristors Offering Reliable Switching On A Biological Time Scale, Yuriy V. Pershin, Liya Patel, Bapi Bera, Doug Aaron, Stephen A. Sarles 2026 University of South Carolina

Egain Tube Memristors Offering Reliable Switching On A Biological Time Scale, Yuriy V. Pershin, Liya Patel, Bapi Bera, Doug Aaron, Stephen A. Sarles

Faculty Publications

Memristive devices have been considered promising candidates for nature-inspired computing and in-memory information processing. However, experimental devices developed to date typically show significant variability and function at different time scales than biological neurons and synapses. This study presents a memristive device comprised of liquid-metal eutectic gallium indium (EGaIn) contained within a mm-scale tube that operates via a bulk, voltage-dependent switching mechanism and exhibits distinct unipolar resistive switching characteristics that occur on a biological time scale (tens of milliseconds). The switching mechanism involves voltage-controlled growth and dissolution of an oxide layer on the surface of the liquid metal in contact with …


The Detection Of Marine Microseismic Activity With The Cuore Tonne-Scale Cryogenic Experiment, D. Q. Adams, C. Aldunio, K. Alfonso, A. Armatol, Frank Avignone III, O. Azzolini, G. Bari, F. Bellini, G. Benato, M. Beretta, C. Bucci, J. Camilleri, A. Caminata, A. Campani, J. Cao, C. Capelli, S. Capelli, L. Capelli, J. Capelli, A. Caminata, Et. Al. 2026 University of South Carolina

The Detection Of Marine Microseismic Activity With The Cuore Tonne-Scale Cryogenic Experiment, D. Q. Adams, C. Aldunio, K. Alfonso, A. Armatol, Frank Avignone Iii, O. Azzolini, G. Bari, F. Bellini, G. Benato, M. Beretta, C. Bucci, J. Camilleri, A. Caminata, A. Campani, J. Cao, C. Capelli, S. Capelli, L. Capelli, J. Capelli, A. Caminata, Et. Al.

Faculty Publications

Vibrations from experimental setups and the environment are a persistent source of noise for low-temperature calorimeters searching for rare events, including neutrinoless double beta (0νββ) decay or dark matter interactions. Such noise can significantly limit experimental sensitivity to the physics case under investigation. Here, we report the detection of marine microseismic vibrations using mK-scale calorimeters. This study employs a multi-device analysis correlating data from CUORE, the leading experiment in the search for 0νββ decay with mK-scale calorimeters, and the Copernicus Earth Observation program, revealing the seasonal impact of Mediterranean Sea activity on CUORE’s …


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