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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 …


Discovery Of Dynamical Structures Mapping Chaotic Transport Pathways In The Earth–Moon Cr3bp, Tyler J. Kapolka, Christina E. Paljug, Robert A. Bettinger, Rachel Oliver, Bruce A. Cox, Jeremiah A. Specht 2026 Air Force Institute of Technology

Discovery Of Dynamical Structures Mapping Chaotic Transport Pathways In The Earth–Moon Cr3bp, Tyler J. Kapolka, Christina E. Paljug, Robert A. Bettinger, Rachel Oliver, Bruce A. Cox, Jeremiah A. Specht

Faculty Publications

Chaos; Deterministic chaos; Earth–Moon system; Poincaré map; Quasi-chaotic; Surface of section /// For the Circular Restricted 3-Body Problem (CR3BP), the topologies present within a Poincaré map enable the extraction of useful information regarding periodic, quasi-periodic, and chaotic trajectory behavior. Aside from the prominent topologies that follow distinct concentric patterns around fixed points, indicative of the periodic and quasi-periodic motion that is often the central focus of CR3BP research, there are also many “dusty” regions on the Poincaré map that appear random without an apparent structure and are indicative of chaotic motion. This paper, for the first time in literature, identifies …


Anomalous Spontaneous Induction Of Magnetic And Electric Fields In Dense Quark Matter, Efrain J. Ferrer, Jose Miguel Perez-Fernandez 2026 The University of Texas Rio Grande Valley

Anomalous Spontaneous Induction Of Magnetic And Electric Fields In Dense Quark Matter, Efrain J. Ferrer, Jose Miguel Perez-Fernandez

Physics & Astronomy Faculty Publications

In this paper, we will demonstrate that a dense quark-matter system in the dual chiral density wave (DCDW) phase behaves as a ferromagnet in the sense that its magnetic-field dependent magnetization remains different from zero even at 𝐵 →0. The corresponding permanent magnetization is a function of the baryonic chemical potential 𝜇, decreasing up to zero as 𝜇 increases in the range of intermediate densities (312  MeV⩽𝜇⩽342  MeV) and then increasing from zero in the higher density interval 490  MeV⩽𝜇⩽550  MeV. We will show that this system’s ability to generate permanent magnetization, together with the existence of the axial anomaly, …


A New Highly Oxygen-Deficient And Cubic Pr3Zro8-Δ For Intermediate-Temperature Thermochemical Production Of Oxygen And Hydrogen, Jiaxin Lu, Yongliang Zhang, Luhong Chen, Yan Chen, Ke An, Yasser Shoukry, Xinfang Jin, Zhi-Hao Wang, Sai Mu, Kevin Huang 2026 University of South Carolina

A New Highly Oxygen-Deficient And Cubic Pr3Zro8-Δ For Intermediate-Temperature Thermochemical Production Of Oxygen And Hydrogen, Jiaxin Lu, Yongliang Zhang, Luhong Chen, Yan Chen, Ke An, Yasser Shoukry, Xinfang Jin, Zhi-Hao Wang, Sai Mu, Kevin Huang

Faculty Publications

Two-step thermochemical cycles offer a clean route for hydrogen and oxygen production but are typically limited to high temperatures exceeding 1500 °C. Lowering operating temperatures would enable the use of alternative heat sources such as industrial waste heat. Here, we report Pr3ZrOas a new enabling material for efficient intermediate-temperature redox cycling, with thermal reduction at 900 °C in argon and steam oxidation at 400 °C. Pr3ZrOadopts a face-centered cubic structure similar to CeO2 but exhibits significantly greater oxygen deficiency, achieving average oxygen and hydrogen fluxes of 331.7 and 70.3 µmol·g-1, respectively, …


A 682-Second X-Ray Periodicity In Ch Cygni: Evidence For A Magnetic White Dwarf, Manuel Pichardo Marcano, Thomas J. Maccarone, Liliana E. Rivera Sandoval 2026 Texas Tech University

A 682-Second X-Ray Periodicity In Ch Cygni: Evidence For A Magnetic White Dwarf, Manuel Pichardo Marcano, Thomas J. Maccarone, Liliana E. Rivera Sandoval

Physics & Astronomy Faculty Publications

Symbiotic stars are interacting binaries consisting of a red giant and typically a white dwarf (WD), which are important as potential Type Ia supernova progenitors. Despite theoretical predictions that WDs in symbiotic systems should often be magnetic, direct evidence has been elusive. We report the discovery of a 682.5 ± 7 s periodicity in the XMM–Newton X-ray light curve that we interpret as the spin period of the WD in CH Cygni. This detection provides strong evidence for a magnetic WD in CH Cygni, making it only the second WD symbiotic star with confirmed X-ray pulsations after R Aquarii. Our …


Constraining The Impact Threat From Small Bodies In Near Earth And Cislunar Space, Skylar G. Butler, Jarrett Dieterle, Henry Sanders, Aiden Kelleher 2026 Embry-Riddle Aeronautical University

Constraining The Impact Threat From Small Bodies In Near Earth And Cislunar Space, Skylar G. Butler, Jarrett Dieterle, Henry Sanders, Aiden Kelleher

Student Research Symposium (SRS)

Understanding and mitigating the impact threat posed by small bodies in near-Earth and cislunar space is vital for planetary defense, spacecraft safety, and sustainable space operations. This research integrates dynamical evolution modeling, synthetic observations, and reprocessed infrared data to assess the origins and potential hazards of debris from young asteroid families. By modeling the trajectories and orbital evolution of fragments from the Datura, Emilkowalski, 1992 YC2, Lucascavin (Nesvorný & Vokrouhlický, 2006), and Veritas (Nesvorný et al., 2003) families, we constrain how these sources contribute to near-Earth debris populations. Reprocessing Infrared Astronomical Satellite (IRAS) data with Fourier-filtering techniques reveals fine-structure variations …


Solar Wind–Magnetosphere Coupling During The September 2025 Cme: Multi-Spacecraft Analysis Using Mms And Omni Data, Skylar G. Butler, Margret Stanley 2026 Embry-Riddle Aeronautical University

Solar Wind–Magnetosphere Coupling During The September 2025 Cme: Multi-Spacecraft Analysis Using Mms And Omni Data, Skylar G. Butler, Margret Stanley

Student Research Symposium (SRS)

A sequence of two coronal mass ejections (CMEs) impacted Earth in early September 2025, producing consecutive geomagnetic disturbances. The first CME, launched on 31 August 2025 and observed as a halo in SOHO/LASCO imagery, reached Earth on 1 September (~20:45 UTC), generating a clear interplanetary shock. OMNI 1-min solar-wind data show a sudden rise in |B| from ≈ 5 nT to > 25 nT, proton density and velocity increases (≈ 350 → 600 km s⁻¹), and a southward IMF Bz interval that drove enhanced coupling. The Kyoto Dst index recorded a sudden storm commencement followed by a minimum of −75 nT …


How Hidden Companions Skew Stellar Ages: A Binary-Inclusive Analysis Of Ngc 2168, Skylar G. Butler 2026 Embry-Riddle Aeronautical University

How Hidden Companions Skew Stellar Ages: A Binary-Inclusive Analysis Of Ngc 2168, Skylar G. Butler

Student Research Symposium (SRS)

We expand upon our previous analysis of NGC 2168 (M35), which investigated the precision of isochrone-based age determination for individual main-sequence stars using photometric modeling. Building on that earlier framework, we now assess how inferred stellar ages change when each object is modeled under the assumption that it may possess an unresolved binary companion. Using post burn in posterior samples from the same dataset, we computed the mean Stage 3 ages for more than 3,000 cluster members with binaries turned on, allowing a direct comparison to our prior results with binaries turned off. The resulting age distribution peaks near 2.1 …


Modeling The Secondary Catastrophic Disruption Of The Veritas Family, Jarrett Dieterle, Skylar G. Butler, Aiden Kelleher 2026 Embry-Riddle Aeronautical University

Modeling The Secondary Catastrophic Disruption Of The Veritas Family, Jarrett Dieterle, Skylar G. Butler, Aiden Kelleher

Student Research Symposium (SRS)

The Veritas asteroid family, located in the outer main belt, is believed to have formed from the catastrophic breakup of a parent body approximately 8.3 million years ago (e.g., Nesvorný et al., 2003). Larger fragments remained in the main belt, while smaller particles evolved inward under radiation forces, forming a toroidal dust structure observable in infrared data as paired bands. Previous studies (e.g., Dermott et al., 2001) have shown that these bands can be linked to their parent families and modeled from their initial disruptions. We propose that the 10° dust bands associated with Veritas may record evidence of a …


Building The Erau Solar Telescope: Advancing Heliophysics Research And Education Through Optical Innovation, Erin Abraham, Sarah Hoover, Skylar G. Butler, Margret Stanley, Gwynlyn Hannah 2026 Embry-Riddle Aeronautical University

Building The Erau Solar Telescope: Advancing Heliophysics Research And Education Through Optical Innovation, Erin Abraham, Sarah Hoover, Skylar G. Butler, Margret Stanley, Gwynlyn Hannah

Student Research Symposium (SRS)

The new Embry-Riddle Aeronautical University (ERAU) Solar Telescope represents a campus-wide collaboration to design and install a high-resolution solar observatory. The ERAU solar telescope, aiming for first light by Summer 2026, will integrate research-grade instrumentation, student training opportunities, and expand public engagement with the ERAU observatory. The telescope is housed within a 2.3-meter refurbished dome structure whose electrical and structural systems are being upgraded to support automated dome rotation and environmental stabilization. The optical design features a multi-element lens and mirror assembly optimized for a 1° field of view. The optical assembly includes a downport centered in the dome that …


Investigation Of Biofilm Formation And Osmotic Stress Tolerance Of Nonmotile E. Coli Mg1655 In Simulated Microgravity, Tyler Jenkins 2026 Embry-Riddle Aeronautical University

Investigation Of Biofilm Formation And Osmotic Stress Tolerance Of Nonmotile E. Coli Mg1655 In Simulated Microgravity, Tyler Jenkins

Student Research Symposium (SRS)

Simulated microgravity presents multiple physiological stressors for astronauts, including bone demineralization, muscle loss, and weakening of the immune system (Chavez et al., 2024). Bacteria serve as viable model organisms to study physiological changes because of their abundance in the human digestive system and skin. Motility in bacteria plays a significant role in cell survival, but few studies have been conducted on microgravity’s effect on motility phenotypes. While motile strains like K12 have been studied extensively under microgravity conditions (Topolski et al., 2022; Chavez et al., 2024), the effects of simulated microgravity on non-motile strains are largely unknown. To better understand …


Characterizing The Solar Sources Of Periodic Mesoscale Solar Wind Structures Responsible For Radiation Belt Particle Loss: Results And Implications For Space Weather Forecasting, Grace Gratton 2026 Embry-Riddle Aeronautical University

Characterizing The Solar Sources Of Periodic Mesoscale Solar Wind Structures Responsible For Radiation Belt Particle Loss: Results And Implications For Space Weather Forecasting, Grace Gratton

Student Research Symposium (SRS)

It is now well-established that the ambient solar wind is dynamic and highly structured at mesoscales – scales larger than kinetic, but smaller than CMEs/SIRs. These structures are often created at the Sun and survive to 1 AU, where they form the ground-state of space weather as they continually buffet Earth's magnetosphere, the moon, and Mars. Two primary ways that mesoscale structures pose significant risks to spacecraft and astronauts are through driving radiation belt depletion, and amplifying the hazards of CMEs and SIRs through upstream solar wind preconditioning. Characterizing the solar origins and solar wind properties of geoeffective mesoscale structures …


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