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Faculty Publications

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Articles 1 - 30 of 692

Full-Text Articles in Astrophysics and Astronomy

How Neutron Star Radii Encode The Dense-Matter Equation Of State And Hadron-Quark Transition, Bao-An Li, Xavier Grundler Nov 2026

How Neutron Star Radii Encode The Dense-Matter Equation Of State And Hadron-Quark Transition, Bao-An Li, Xavier Grundler

Faculty Publications

We investigate how future high-precision neutron star (NS) radius measurements encode microscopic information about the dense-matter equation of state (EOS), focusing on a possible first-order hadron–quark phase transition and the resulting mass–radius topology. Within a Bayesian framework using metamodel EOSs with nine microscopic parameters, we analyze mock radius measurements R 1.4 =11.9 ± σ R km with σ =0.9 and 0.1 km for canonical NSs. Rather than relying only on marginalized posterior probability distributions, we introduce inverse EOS–radius mappings by studying the conditional mean of each EOS parameter as a function of the model-predicted canonical radius R R 1.4 . …

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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 …

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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.

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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 …

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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 …

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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 …

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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 …

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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 Feb 2026

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 …

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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, …

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Large Magnetoresistance And Quantum Oscillations Observed In Superconducting Β-Irsn4, Smita Speer, Yuriy V. Pershin, Joanna Blawat, John Singleton, Rongying Jin Feb 2026

Large Magnetoresistance And Quantum Oscillations Observed In Superconducting Β-Irsn4, Smita Speer, Yuriy V. Pershin, Joanna Blawat, John Singleton, Rongying Jin

Faculty Publications

Diverse quantum phenomena have been observed in TSn4 transition metal (T) stannides, includ ing superconductivity, nontrivial topology, and large magnetoresistance (MR) at low temperat ures. Here, we report the experimental and theoretical investigation of tetragonal β-IrSn4 (space group I41/acd) with the lattice parameters a = 6.362(3) Å and c = 22.723(0) Å. The temperature dependence of the electrical resistivity indicates that β-IrSn4 is a good metal with Fermi-liquid behavior above the superconducting transition at Tc ∼ 0.7 K. Magnetic susceptibility measure ments indicate it is non-magnetic. However, positive transverse MR with …

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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, …

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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 …

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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 …

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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 …

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Hyena: An Observing System Simulation Experiment For Hypothetical Energetic Neutral Atom Imagers, Joel Tibbetts, Amy Keesee, Matina Gkioulidou, Robert Demajistre, Viacheslav Merkin Jan 2026

Hyena: An Observing System Simulation Experiment For Hypothetical Energetic Neutral Atom Imagers, Joel Tibbetts, Amy Keesee, Matina Gkioulidou, Robert Demajistre, Viacheslav Merkin

Faculty Publications

Mesoscale plasma sheet flows are widely understood to be a critical component of the overall picture of energy, particle, and magnetic flux transport during periods of geomagnetic activity. Without simultaneous measurements with true global coverage, the short lifetime (~10 min) and localized spatial extents (~1–3 RE in azimuth) of these structures make obtaining a global picture of their contributions to stormtime magnetosphere dynamics difficult to characterize. Energetic neutral atom (ENA) imaging can enable remote mapping of plasma energization in the magnetosphere; however, its line-of-sight integrated nature, coupled with the challenging-to-characterize attributes of the target physical phenomena, means that numerous …

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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 …

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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 …

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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 …

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Large Bandgap Observed On The Surfaces Of Euzn2As2 Single Crystals, Dejia Kong, Siavash Karbasizadeh, Ganesh Narasimha, Paras Regmi, Chenggang Tao, Chenggang Tao, Sai Mu, Rama Vasudevan, Ian Harrison, Rongying Jin, Zheng Gai Jul 2025

Large Bandgap Observed On The Surfaces Of Euzn2As2 Single Crystals, Dejia Kong, Siavash Karbasizadeh, Ganesh Narasimha, Paras Regmi, Chenggang Tao, Chenggang Tao, Sai Mu, Rama Vasudevan, Ian Harrison, Rongying Jin, Zheng Gai

Faculty Publications

EuZn2As2 (M = Zn, Cd, In, Sn etc.) is an excellent material system for studying magnetism-tuned topological properties. However, discrepancies exist between experimental data and theoretical calculations regarding the bulk and surface bandgaps. In this work, cleaved EuZn2As2 crystals are studied using scanning tunneling microscopy/spectroscopy and density functional theory calculations. Triangular-shaped defect-induced modifications in the local density of states help distinguish between Eu-terminated and AsZn-terminated surfaces. While large bandgaps ( ~1.5 eV at 77 K) are observed on both pristine surfaces, the bandgap size is found to be highly sensitive to local heterogeneity, tending …

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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+ …

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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 …

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Final Results Of The Majorana Demonstrator’S Search For Double-Beta Decay Of 76Ge To Excited States Of 76Se, I. J. Arnquist, Frank Avignone Iii, A. S. Barabash, E. Blalock, B. Bos, M. Busch, Y. -D. Chan, J. R. Chapman, C. D. Chrisofferson, Et. Al., Majorana Collaboration Jun 2025

Final Results Of The Majorana Demonstrator’S Search For Double-Beta Decay Of 76Ge To Excited States Of 76Se, I. J. Arnquist, Frank Avignone Iii, A. S. Barabash, E. Blalock, B. Bos, M. Busch, Y. -D. Chan, J. R. Chapman, C. D. Chrisofferson, Et. Al., Majorana Collaboration

Faculty Publications

76Ge can ββ decay into three possible excited states of 76Se, with the emission of two or, if the neutrino is Majorana, zero neutrinos. None of these six transitions have yet been observed. The Majorana Demonstrator was designed to study ββ decay of 76Ge using a low background array of high purity germanium detectors. With 98.2 kg·y of isotopic exposure, the demonstrator sets the strongest half-life limits to date for all six transition modes. For 2νββ to the 01+ state of 76Se, this search has begun to probe for the first time half-life …

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Enhanced Nuclear Binding Near The Proton Drip Line Opens Possible Bypass Of The 64Ge Rapid Proton Capture Process Waiting Point, Zachary Meisel, W.-J Ong, J. S. Ranhawa May 2025

Enhanced Nuclear Binding Near The Proton Drip Line Opens Possible Bypass Of The 64Ge Rapid Proton Capture Process Waiting Point, Zachary Meisel, W.-J Ong, J. S. Ranhawa

Faculty Publications

We performed astrophysics model calculations with updated nuclear data to identify a possible bypass of the 64Ge waiting point, a defining feature of the rapid proton capture (rp) process that powers type I X-ray bursts on accreting neutron stars. We find that the rp-process flow through the 64Ge bypass could be up to 36% for astrophysically relevant conditions. Our results call for new studies of 65Se, including the nuclear mass, β-delayed proton emission branching, and nuclear structure as it pertains to the 64As(p, γ) reaction rate at X-ray burst temperatures.

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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.

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Global Ionospheric F Region Parameters From Gnss-Pod Limb Measurements: Evaluations And Comparisons With Two Empirical Models - Iri-2020 And Nequick-2, Nimalan Swarnalingam, Dong L. Wu, Dieter Bilitza, Daniel J. Emmons, Cornelius Csar Jude H. Salinas, Artem Smirnov, Yenca Migoya-Oru Apr 2025

Global Ionospheric F Region Parameters From Gnss-Pod Limb Measurements: Evaluations And Comparisons With Two Empirical Models - Iri-2020 And Nequick-2, Nimalan Swarnalingam, Dong L. Wu, Dieter Bilitza, Daniel J. Emmons, Cornelius Csar Jude H. Salinas, Artem Smirnov, Yenca Migoya-Oru

Faculty Publications

An optimal estimation (OE) technique has recently been developed for F region electron density (Ne) using Global Navigation Satellite System (GNSS) limb sounding on low Earth orbit (LEO) satellites (COSMIC-2, Spire, and FengYun-3). This method provides unprecedented spatiotemporal sampling for global monthly Ne climatology within 100–500 km in 2 hr intervals. The global dataset, collected during mid to moderately high solar activity, is compared with leading models: IRI-2020 and NeQuick-2. Diurnal variations in summer, winter, and equinoctial months are examined for the F2-layer peak, as well as the topside and bottomside of the F region. The observed and modeled NmF2 …

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Characterization Of Chromium Impurities In Β‐Ga2O3, Mark E. Turiansky, Sai Mu, Lukas Razinkovas, Kamyar Parto, Sahil D. Patel, Sean Doan, Ganesh Pokharel, Steven K. Gomez Alvarado, Stephen D. Wilson, Galan Moody, Chris G. Van De Wallie Mar 2025

Characterization Of Chromium Impurities In Β‐Ga2O3, Mark E. Turiansky, Sai Mu, Lukas Razinkovas, Kamyar Parto, Sahil D. Patel, Sean Doan, Ganesh Pokharel, Steven K. Gomez Alvarado, Stephen D. Wilson, Galan Moody, Chris G. Van De Wallie

Faculty Publications

Chromium is a common transition-metal impurity that is easily incorporated during crystal growth. It is perhaps best known for giving rise to the 694.3 nm (1.786 eV) emission in Cr-doped A2O3, exploited in ruby lasers. Chromium has also been found in monoclinic gallium oxide, a wide-bandgap semiconductor being pursued for power electronics. In this work, we thoroughly characterize the behavior of Cr in Ga2O3 through theoretical and experimental techniques. β-Ga2O3samples are grown with the floating zone method and show evidence of a sharp photoluminescence signal, reminiscent of ruby. …

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Dual-Baseline Search For Active-To-Sterile Neutrino Oscillations In Nova, A. Back, N. Balashov, P. Baldi, B. A. Bambah, E. F. Bannister, A. Barros, A. Bat, K. Bays, R. Bernstein, T.J.C. Bezerra, V. Bhatnagar, D. Bhattarai, B. Bhuyan, J. Bian, A.C. Booth, R. Bowles, B. Brahma, C. Bromberg, N. Buchanan, A. Butkevich, Roberto Petti, Et. Al. Feb 2025

Dual-Baseline Search For Active-To-Sterile Neutrino Oscillations In Nova, A. Back, N. Balashov, P. Baldi, B. A. Bambah, E. F. Bannister, A. Barros, A. Bat, K. Bays, R. Bernstein, T.J.C. Bezerra, V. Bhatnagar, D. Bhattarai, B. Bhuyan, J. Bian, A.C. Booth, R. Bowles, B. Brahma, C. Bromberg, N. Buchanan, A. Butkevich, Roberto Petti, Et. Al.

Faculty Publications

No abstract provided.

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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 …

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New Insights Into Supradense Matter From Dissecting Scaled Stellar Structure Equations, Bao-Jun Cai, Bao-An Li Dec 2024

New Insights Into Supradense Matter From Dissecting Scaled Stellar Structure Equations, Bao-Jun Cai, Bao-An Li

Faculty Publications

The strong-field gravity in general relativity (GR) realized in neutron stars (NSs) renders the equation of state (EOS) P(ε) of supradense neutron star matter to be essentially nonlinear and refines the upper bound for ϕ≡P/ε to be much smaller than the special relativity (SR) requirement with linear EOSs, where P andεare respectively the pressure and energy density of the system considered. Specifically, a tight bound ϕ ≲ 0.374 is obtained by perturbatively anatomizing the intrinsic structures of the scaled Tolman–Oppenheimer–Volkoff (TOV) equations without using any input nuclear EOS. New insights gained from this novel analysis provide EOS-model-independent constraints on the …

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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 …

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