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Full-Text Articles in Astrophysics and Astronomy

Table Of Contents May 2026

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Inferring The Breakdown Scales Of The Chiral Expansions For GA And MN, Andreas Ekström, Daniel R. Phillips, Lucas Platter, Matthias Schindler Apr 2026

Inferring The Breakdown Scales Of The Chiral Expansions For GA And MN, Andreas Ekström, Daniel R. Phillips, Lucas Platter, Matthias Schindler

Faculty Publications

We apply Bayesian inference to the order-by-order chiral perturbation theory (χPT) expansions for the axial-vector coupling constant gA and the nucleon mass mN, and thereby infer the scales at which χPT breaks down for these two observables. Using a pointwise Bayesian analysis, we find that the inferred breakdown scales are notably different for the two observables. For the chiral expansion of gA, we obtain 251+20−50 MeV and 211+20−30 MeV using two distinct sets of low-energy constants, while for the chiral expansion of mN we infer a significantly …


Searching For Temporal Variations In The Fine-Structure Constant Using Espresso Spectrograph Data, David Hoffman Iv Apr 2026

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 …


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

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 …


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

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.


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

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 …


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

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 …


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

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. Feb 2026

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 …


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 Feb 2026

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 Pr3ZrO8 as a new enabling material for efficient intermediate-temperature redox cycling, with thermal reduction at 900 °C in argon and steam oxidation at 400 °C. Pr3ZrO8 adopts 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, …


Crystal Structures, Optical Behavior, And Magnetic Properties In Hydrated Lanthanide Iron Sulfates, Chole Jones, Silu Huang, Tyler L. Spano, Eric A. Gabilondo, Mohammed Al-Fahdi, Kara Trim, Mary Douglas, Rongying Jin, Andrew Miskowiec, P. Shiv Halasyamani, Ming Hu, Jie Ling Jan 2026

Crystal Structures, Optical Behavior, And Magnetic Properties In Hydrated Lanthanide Iron Sulfates, Chole Jones, Silu Huang, Tyler L. Spano, Eric A. Gabilondo, Mohammed Al-Fahdi, Kara Trim, Mary Douglas, Rongying Jin, Andrew Miskowiec, P. Shiv Halasyamani, Ming Hu, Jie Ling

Faculty Publications

Single crystals of LnFe(SO4)3(H2O)2 (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm; compounds 1–11) and LnFe(SO4)3(H2O) (Ln = Tm, Yb, Lu; compounds 12–14) were synthesized under hydrothermal conditions. Single-crystal X-ray diffraction (SCXRD) analysis revealed that the dihydrated compounds (1–11) crystallize in centrosymmetric (CS) structures, with the lanthanide ions adopting eight-coordinate geometries. In contrast, the monohydrated compounds (12–14) exhibit noncentrosymmetric (NCS) structures, where the lanthanide ions are seven-coordinated. Vibrating sample magnetometry (VSM) confirmed that compounds 2, …


Gatos – Xi. Excess Dust Heating In The Narrow-Line Regions Of Nearby Agn Revealed With Jwst/Miri, Houda Haidar, David J. Rosario, Ismael García-Bernete, Almudena Alonso-Herrero, Anelise Audibert, Steph Campbell, Chris M. Harrison, Tiago Costa, Laura Hermosa Muñoz, Françoise Combes, Dimitra Rigopoulou, Claudio Ricci, Cristina Ramos Almeida, Enrica Bellocchi, Peter Boorman, Andrew Bunker, Richard Davies, Daniel Delaney, Tanio Díaz Santos, Federico Esposito, Enrique Lopez Rodriguez, Et. Al. Jan 2026

Gatos – Xi. Excess Dust Heating In The Narrow-Line Regions Of Nearby Agn Revealed With Jwst/Miri, Houda Haidar, David J. Rosario, Ismael García-Bernete, Almudena Alonso-Herrero, Anelise Audibert, Steph Campbell, Chris M. Harrison, Tiago Costa, Laura Hermosa Muñoz, Françoise Combes, Dimitra Rigopoulou, Claudio Ricci, Cristina Ramos Almeida, Enrica Bellocchi, Peter Boorman, Andrew Bunker, Richard Davies, Daniel Delaney, Tanio Díaz Santos, Federico Esposito, Enrique Lopez Rodriguez, Et. Al.

Faculty Publications

We present James Webb Space Telescope/Mid-Infrared Instrument imaging of eight nearby active galactic nuclei (AGN) from the GATOS (Galactic Activity, Torus, and Outflow Survey) survey to investigate the physical conditions of extended dust in their narrow-line regions (NLRs). In four galaxies (ESO 428–G14, NGC 4388, NGC 3081, and NGC 5728), we detect spatially resolved dust structures extending ∼100–200 pc along the NLR. In these systems, we find a strong link between the morphology of the dust, the radio ejecta, and the coronal [Si VI] emission, implying that dust carries imprints of the processes shaping the NLR. Using spatially resolved …


First Results On The Search For Lepton Number Violating Neutrinoless Double-Β Decay With The Legend-200 Experiment, H. Acharya, N. Ackermann, M. Agostini, A. Alexander, C. Andreoiu, G. R. Araujo, Frank Avignone Iii, M. Babicz, W. Bae, A. M. Bakalyarov, M. Balata, A. S. Barabash, C. J. Barton, L. Baudis, C. Bauer, E. Bernieri, L. Bezrukov, K. H. Bhimani, V. Biancaccu, E. Blalock, Et. Al. Jan 2026

First Results On The Search For Lepton Number Violating Neutrinoless Double-Β Decay With The Legend-200 Experiment, H. Acharya, N. Ackermann, M. Agostini, A. Alexander, C. Andreoiu, G. R. Araujo, Frank Avignone Iii, M. Babicz, W. Bae, A. M. Bakalyarov, M. Balata, A. S. Barabash, C. J. Barton, L. Baudis, C. Bauer, E. Bernieri, L. Bezrukov, K. H. Bhimani, V. Biancaccu, E. Blalock, Et. Al.

Faculty Publications

The LEGEND Collaboration is searching for neutrinoless double-beta (0νββ) decay by operating high-purity germanium detectors enriched in 76Ge in a low-background liquid argon environment. Building on key technological innovations from the GERmanium Detector Array (GERDA) experiment and the MAJORANA DEMONSTRATOR experiment, LEGEND-200 has performed a first 0νββ decay search based on 61.0 kg yr of data. Over half of this exposure comes from our highest performing detectors, including newly developed inverted-coaxial detectors, and is characterized by an estimated background level of 0.5+0.3−0.2 cts/(keV ton yr) in the 0νββ decay signal region. A combined …


Jwst Interferometric Imaging Reveals The Dusty Torus Obscuring The Supermassive Black Hole Of Circinus Galaxy, Enrique Lopez Rodriguez, Joel Sanchez-Bermudez, Omaira González-Martín, Robert Nikutta, Ryan M. Lau, Deepashri Thatte, Julien H. Girard, Ismael García-Bernete, Matthew J. Hankins Jan 2026

Jwst Interferometric Imaging Reveals The Dusty Torus Obscuring The Supermassive Black Hole Of Circinus Galaxy, Enrique Lopez Rodriguez, Joel Sanchez-Bermudez, Omaira González-Martín, Robert Nikutta, Ryan M. Lau, Deepashri Thatte, Julien H. Girard, Ismael García-Bernete, Matthew J. Hankins

Faculty Publications

The dusty and molecular torus is an elusive structure surrounding supermassive black holes, yet its importance is unequivocal for understanding feedback and accretion mechanisms. The torus and accretion disk feed the inspiraling gas onto the active nucleus, launching outflows that fundamentally connect the active nucleus’s activity to the host galaxy. In this work, we utilize the aperture-masking interferometric mode onboard the JWST to achieve a resolution of 0.08" at 4.3 μm and bring out the fainter features in the central 10 pc of the Circinus galaxy. We show that most of the dust mass is located along the equatorial …


Joint Neutrino Oscillation Analysis From The T2k And Nova Experiments, S. Abubakar, M. A. Acero, B. Acharya, P. Adamson, N. Anfimov, A. Antoshkin, E. Arrieta-Diaz, L. Asquith, A. Aurisano, D. Azevedo, A. Back, N. Balashov, P. Baldi, A. Bambah, E. F. Barenboim, A. Bashyal, A. Basti, K. Bromberg, N. Buchanan, Roberto Petti Oct 2025

Joint Neutrino Oscillation Analysis From The T2k And Nova Experiments, S. Abubakar, M. A. Acero, B. Acharya, P. Adamson, N. Anfimov, A. Antoshkin, E. Arrieta-Diaz, L. Asquith, A. Aurisano, D. Azevedo, A. Back, N. Balashov, P. Baldi, A. Bambah, E. F. Barenboim, A. Bashyal, A. Basti, K. Bromberg, N. Buchanan, Roberto Petti

Faculty Publications

The landmark discovery that neutrinos have mass and can change type (or flavour) as they propagate—a process called neutrino oscillation1,2,3,4,5,6—has opened up a rich array of theoretical and experimental questions being actively pursued today. Neutrino oscillation remains the most powerful experimental tool for addressing many of these questions, including whether neutrinos violate charge-parity (CP) symmetry, which has possible connections to the unexplained preponderance of matter over antimatter in the Universe7,8,9,10,11. Oscillation measurements also probe the mass-squared differences between the different neutrino mass states (Δm2), whether there are two light states and a heavier …


Detecting Polar Ring Galaxies Via Deep Learning, Fawad Kirmani, Anathavishnu S. Unnii, Varsha P. Kulkarni, Kyle Lackey, John R. Rose Oct 2025

Detecting Polar Ring Galaxies Via Deep Learning, Fawad Kirmani, Anathavishnu S. Unnii, Varsha P. Kulkarni, Kyle Lackey, John R. Rose

Faculty Publications

Polar ring galaxies (PRGs) are peculiar galaxies that show a ring of stars, gas, and dust oriented roughly over the poles of the central ‘host’ galaxy (i.e. roughly orthogonal to the disc of the host galaxy). The formation models for these rings involve mergers or tidal interactions of the host galaxy with another galaxy. Although the identified PRGs look different from each other, they all have a ring that is not in the same plane as the disc of the host galaxy. Unlike in galaxies such as our Milky Way, where stars form in spiral arms, the rings exemplify an …


Absence Of Phonon Softening Across A Charge Density Wave Transition Due To Quantum Fluctuations, Yubi Chen, Terawit Kongruengkit, Andrea Capa Salinas, Runqing Yang, Yujie Quan, Fanghao Zhang, Ganesh Pokharel, Linus Kautzsch, Stephen D. Wilson, Sai Mu Aug 2025

Absence Of Phonon Softening Across A Charge Density Wave Transition Due To Quantum Fluctuations, Yubi Chen, Terawit Kongruengkit, Andrea Capa Salinas, Runqing Yang, Yujie Quan, Fanghao Zhang, Ganesh Pokharel, Linus Kautzsch, Stephen D. Wilson, Sai Mu

Faculty Publications

Kagome metals have emerged as a frontier in condensed matter physics due to their potential to host exotic quantum states. Among these, CsV3Sb5 has attracted significant attention for the unusual coexistence of charge density wave (CDW) order and unconventional superconductivity, presenting an ideal system for exploring the emergent phenomena from the interplay of phonons, electronic fluctuations, and topological effects. The nature of CDW formation in CsV3Sb5 is unconventional and has sparked considerable debate. In this study, we examine the origin of the CDW state via ab initio finite-temperature simulations of the lattice dynamics. Through a comparative study …


Table Of Contents Jul 2025

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Electroexcitation Of Nucleon Resonances And Emergence Of Hadron Mass, Patrick Achenbach, Daniel S. Carman, Ralf Gothe, Kyungseon Joo, Victor I. Mokeev, Craig D. Roberts Jul 2025

Electroexcitation Of Nucleon Resonances And Emergence Of Hadron Mass, Patrick Achenbach, Daniel S. Carman, Ralf Gothe, Kyungseon Joo, Victor I. Mokeev, Craig D. Roberts

Faculty Publications

Developing an understanding of phenomena driven by the emergence of hadron mass (EHM) is one of the most challenging problems in the Standard Model. This discussion focuses on the impact of results on nucleon resonance (N*) electroexcitation amplitudes (or γvpN*) obtained from experiments during the 6 GeV era in Hall B at Jefferson Lab on understanding EHM. Analyzed using continuum Schwinger function methods (CSMs), these results have revealed new pathways for the elucidation of EHM. A good description of the Δ (1232) 3/2+, N (1440) 1/2+, and Δ (1600) 3/2+ …


Uncovering Multiscale Structure-Property Correlations Via Active Learning In Scanning Tunneling Microscopy, Ganesh Narasimha, Deja Kong, Paras Regmi, Rongying Jin, Zheng Gai, Rama Vasudevan, Maxim Ziatdinov Jun 2025

Uncovering Multiscale Structure-Property Correlations Via Active Learning In Scanning Tunneling Microscopy, Ganesh Narasimha, Deja Kong, Paras Regmi, Rongying Jin, Zheng Gai, Rama Vasudevan, Maxim Ziatdinov

Faculty Publications

Atomic arrangements and local sub-structures fundamentally influence emergent material functionalities. These structures are conventionally probed using spatially resolved studies and the property correlations are deciphered by a researcher based on sequential explorations, thereby limiting the efficiency and scope. Here we demonstrate a multi-scale Bayesian deep-learning based framework that automatically correlates material structure with its electronic properties using scanning tunneling microscopy (STM) measurements in real-time. Its predictions are used to autonomously direct exploration toward regions of the sample that optimize a given material property. This method is deployed on a low-temperature ultra-high vacuum STM to understand the structure-property relationship in a …


Jwst Reveals The Diversity Of Nuclear Obscuring Dust In Nearby Agn: Nuclear Isolation Of Miri/Mrs Data Cubes And Continuum Spectral Fitting, Omaira González-Martín, Daniel J. Díaz-González, Mariela Martínez-Paredes, Almudena Alonso-Herrero, Enrique López-Rodríguez, Begoña García-Lorenzo, Cristina Ramos Almeida, Ismael García-Bernete, Donaji Esparza-Arredondo, Sebastian F. Hoenig, Santiago García-Burillo, Chris Packham, Nancy A. Levenson, Alvaro Labiano, Miguel Pereira-Santaella, Francoise Combes, Anelise Audibert, Erin K.S. Hicks, Lulu Zhang, Enrica Bellocchi, Richard I. Davies, Laura Hermosa Muñoz, Masatoshi Imanishi, Claudio Ricci, Marko Stalevski May 2025

Jwst Reveals The Diversity Of Nuclear Obscuring Dust In Nearby Agn: Nuclear Isolation Of Miri/Mrs Data Cubes And Continuum Spectral Fitting, Omaira González-Martín, Daniel J. Díaz-González, Mariela Martínez-Paredes, Almudena Alonso-Herrero, Enrique López-Rodríguez, Begoña García-Lorenzo, Cristina Ramos Almeida, Ismael García-Bernete, Donaji Esparza-Arredondo, Sebastian F. Hoenig, Santiago García-Burillo, Chris Packham, Nancy A. Levenson, Alvaro Labiano, Miguel Pereira-Santaella, Francoise Combes, Anelise Audibert, Erin K.S. Hicks, Lulu Zhang, Enrica Bellocchi, Richard I. Davies, Laura Hermosa Muñoz, Masatoshi Imanishi, Claudio Ricci, Marko Stalevski

Faculty Publications

We investigate the capabilities of the mid-infrared instrument (MIRI) of JWST to advance our knowledge of active galactic nucleus (AGN) dust using the spectral fitting technique on an AGN collection of 21 nearby (z < 0.05) AGN (7 type-1 and 14 type-2) observations obtained with the medium resolution spectroscopy (MRS) mode. This collection includes publicly available AGN and data from the collaboration of Galactic Activity, Torus, and Outflow Survey (GATOS). We developed a tool named MRSPSFisol that decomposes MRS cubes into point-like and extended contributions. We found statistically good fits for 12 targets with current AGN dust models. The model that provides good fits (χ2/dof< 2) for these 12 targets assumes a combination of clumpy and smooth distribution of dust in a flare-disc geometry where the dust grain size is a free parameter. Still, two and one AGN statistically prefer the disc + wind and the classical clumpy torus model, respectively. However, the currently available models fail to reproduce 40 per cent of the targets, likely due to the extreme silicate features not well reproduced by the models and signatures of water-ice and aliphatic hydrocarbon absorption features in most targets. New models exploring, for instance, new chemistry, are needed to explain the complexity of AGN dust continuum emission observed by JWST.


Deep Learning-Based Superconductivity Prediction And Experimental Tests, Daniel Kaplan, Adam Zheng, Joanna Blawat, Rongying Jin, Robert J. Cava, Viktor Oudovenko, Gabriel Kotliar, Anirvan M. Sengupta, Weiwei Xie Jan 2025

Deep Learning-Based Superconductivity Prediction And Experimental Tests, Daniel Kaplan, Adam Zheng, Joanna Blawat, Rongying Jin, Robert J. Cava, Viktor Oudovenko, Gabriel Kotliar, Anirvan M. Sengupta, Weiwei Xie

Faculty Publications

The discovery of novel superconducting materials is a long-standing challenge in materials science, with a wealth of potential for applications in energy, transportation and computing. Recent advances in artificial intelligence (AI) have enabled expediting the search for new materials by efficiently utilizing vast materials databases. In this study, we developed an approach based on deep learning (DL) to predict new superconducting materials. We have synthesized a compound derived from our DL network and confirmed its superconducting properties in agreement with our prediction. Our approach is also compared to previous work based on random forests (RFs). In particular, RFs require knowledge …


Bound States And Particle Production By Breather-Type Background Field Configurations, Abhishek Rout, Brett Altschul Nov 2024

Bound States And Particle Production By Breather-Type Background Field Configurations, Abhishek Rout, Brett Altschul

Faculty Publications

We investigate the interaction of fermion fields with oscillating domain walls, inspired by breather-type solutions of the sine-Gordon equation, a nonlinear system of fundamental importance. Our study focuses on the fermionic bound states and particle production induced by a time-dependent scalar background field. The fermions couple to two domain walls undergoing harmonic motion, and we explore the resulting dynamics of the fermionic wave functions. We demonstrate that while fermions initially form bound states around the domain walls, the energy provided by the oscillatory motion of the scalar field induces an outward flux of fermions and antifermions, leading to particle production …


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 …


Table Of Contents May 2024

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Creation Of Bound Half-Fermion Pairs By Solitons, Sapan Karki, Brett Altschul Apr 2024

Creation Of Bound Half-Fermion Pairs By Solitons, Sapan Karki, Brett Altschul

Faculty Publications

In the presence of topologically nontrivial bosonic field configurations, the fermion number operator may take on fractional eigenvalues, because of the existence of zero-energy fermion modes. The simplest examples of this occur in 1+1 dimensions, with zero modes attached to kink-type solitons. In the presence of a kink-antikink pair, the two associated zero modes bifurcate into positive and negative energy levels with energies ±ge-gΔ, in terms of the Yukawa coupling g≪1 and the distance Δ between the kink and antikink centers. When the kink and antikink are moving, it seems that there could be Landau–Zener-like transitions between these …


Radiation From An Oscillating Dipole In The Presence Of Photon-Sector Cpt And Lorentz Violation, Joshua O'Connor, Brett Altschul Feb 2024

Radiation From An Oscillating Dipole In The Presence Of Photon-Sector Cpt And Lorentz Violation, Joshua O'Connor, Brett Altschul

Faculty Publications

We examine one of the standard loci for studying electromagnetic wave emission - the radiation from an oscillating electric dipole - in a model in which the electromagnetic sector is modified to include novel CPT- and Lorentz-violating propagation effects involving a preferred axial vector background. We evaluate the vacuum-birefringent radiation fields, including nonperturbative terms where appropriate. In general, the energy momentum carried by the fields in this model is known to have a complicated nonperturbative structure, which cannot be captured by naive power-series expansions in the components of the preferred background vector. However, we nevertheless find that at the lowest …


Muse-Alma Haloes X: The Stellar Masses Of Gas-Rich Absorbing Galaxies, Ramona Augustin, Céline Péroux, Arjun Karki, Varsha Kulkarni, Simon Weng, A Hamanowicz, M Hayes, J C. Howk, G G. Kacprzak, A Klitsch, M A. Zwaan, A Fox, A Biggs, A Y. Fresco, S Kassin, H. Kuntschner Feb 2024

Muse-Alma Haloes X: The Stellar Masses Of Gas-Rich Absorbing Galaxies, Ramona Augustin, Céline Péroux, Arjun Karki, Varsha Kulkarni, Simon Weng, A Hamanowicz, M Hayes, J C. Howk, G G. Kacprzak, A Klitsch, M A. Zwaan, A Fox, A Biggs, A Y. Fresco, S Kassin, H. Kuntschner

Faculty Publications

The physical processes by which gas is accreted onto galaxies, transformed into stars, and then expelled from galaxies are of paramount importance to galaxy evolution studies. Observationally constraining each of these baryonic components in the same system, however, is challenging. Furthermore, simulations indicate that the stellar mass of galaxies is a key factor influencing CGM properties. Indeed, absorption lines detected against background quasars offer the most compelling way to study the cold gas in the circumgalactic medium (CGM). The MUSE-ALMA Haloes survey is composed of quasar fields covered with VLT/MUSE observations, comprising 32 H i absorbers at 0.2 < z < 1.4 and 79 associated galaxies, with available or upcoming molecular gas measurements from ALMA. We use a dedicated 40-orbit HST …


Exiting Inflation With A Smooth Scale Factor, Harry Oslislo, Brett Altschul Nov 2023

Exiting Inflation With A Smooth Scale Factor, Harry Oslislo, Brett Altschul

Faculty Publications

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 of several smooth interpolator candidates, and …


Perturbative Aspects Of Cpt-Even Lorentz-Violating Scalar Chromodynamics, Brett Altschul, L. C.T. Brito, J. C.C. Felipe, S. Karki, A. C. Lehum, A. Yu Petrov Jun 2023

Perturbative Aspects Of Cpt-Even Lorentz-Violating Scalar Chromodynamics, Brett Altschul, L. C.T. Brito, J. C.C. Felipe, S. Karki, A. C. Lehum, A. Yu Petrov

Faculty Publications

In this work, we formulate the theory of Lorentz-violating scalar quantum chromodynamics with an arbitrary non-Abelian gauge group. This theory belongs to the class of models encompassed by the standard model extension framework. At the lowest order in the theory's Lorentz violation parameters, we calculate the divergent quantum corrections, including the renormalization group β-functions of the theory. The Lorentz-violating sector is shown to be scale invariant if there is a particular relation between the couplings.