Open Access. Powered by Scholars. Published by Universities.®

Physics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Series

Discipline
Institution
Keyword
Publication Year
Publication
File Type

Articles 1 - 30 of 21790

Full-Text Articles in Physics

Pentagonal Pdte2 Monolayer For Sustainable Solar-Driven Hydrogen Production, Narender Kumar, Shambhu Bhandari, Dario Alfè, Ravindra Pandey, Nacir Tit Oct 2026

Pentagonal Pdte2 Monolayer For Sustainable Solar-Driven Hydrogen Production, Narender Kumar, Shambhu Bhandari, Dario Alfè, Ravindra Pandey, Nacir Tit

Michigan Tech Publications

This investigation demonstrates that the pentagonal PdTe2 (penta-PdTe2) monolayer is a highly tunable two-dimensional (2D) photocatalyst, characterized by the bandgap of 1.87 eV and high hole mobility. Using density functional theory calculations with the HSE06 functional, we show that tensile strain engineering (particularly at +2% and +3%) is essential for enabling spontaneous water splitting. At these strain values, the valence-band maximum and conduction-band maximum straddle the water redox potentials (H+/H2 and O2/H2O) under both acidic (pH = 0) and neutral (pH = 7) conditions. The monolayer's low hole effective mass facilitates rapid charge extraction, mitigating recombination and driving the oxygen …

Go to article

Quantum Mechanics, Non-Locality, And The Space Discreteness Hypothesis, Wilson A. Zuniga-Galindo Oct 2026

Quantum Mechanics, Non-Locality, And The Space Discreteness Hypothesis, Wilson A. Zuniga-Galindo

School of Mathematical & Statistical Sciences Faculty Publications

The space discreteness hypothesis asserts that the nature of space at short distances is radically different from that at large distances. Based on the Bronstein inequality, here, we use a totally disconnected topological space X as a model for the physical space at short distances. However, we consider the time as a real variable. In this framework, the Dirac–von Neumann formalism can be used. This discreteness hypothesis implies that given two different points in space, there is no continuous curve (a world line) joining them. Consequently, this hypothesis is not compatible with the theory of relativity. We propose R×(R×X)3 as …

Go to article

Temperature Predictions With Zncuins/Zns Quantum Dots, Reu/Fri Program Physics And Astronomy, Amber Banks Aug 2026

Temperature Predictions With Zncuins/Zns Quantum Dots, Reu/Fri Program Physics And Astronomy, Amber Banks

Student Works

For hundreds of years, humans have built thermometers based on the principles of thermal expansion and contraction. In the modern world, there is a need to scale down our thermometers to monitor cellular reactions, both within the human body and within artificial organ chips. Lewis et al. (2020) introduces a nanoscale thermometer based on the thermal expansion of CdTe quantum dots. When ex panded, these dots exhibit systematic changes in photoluminescence (PL) which are recognized by a neural network as an increase in temperature. Our research builds upon the framework of Lewis et al. (2020), testing its feasibility with ZnCuInS/ZnS …

Go to article

Feedback Indices To Evaluate Llm Responses To Rebuttals For Multiple Choice Type Questions, Justin C. Dunlap, Anne-Simone Parent, Ralf Widenhorn Aug 2026

Feedback Indices To Evaluate Llm Responses To Rebuttals For Multiple Choice Type Questions, Justin C. Dunlap, Anne-Simone Parent, Ralf Widenhorn

Physics Faculty Publications and Presentations

We present a set of indices designed to characterize Large Language Model (LLM) responses when challenged with rebuttals during a chat. Assessing how LLMs respond to user dissent is crucial for understanding their reliability and behavior patterns, yet the complexity of human-LLM interactions makes systematic evaluation challenging. Our approach employs a fictitious-response rebuttal method that quantifies LLM behavior when presented with multiple-choice questions followed by deliberate challenges to their fictitious previous response. The indices are specifically designed to detect and measure what could be characterized as sycophantic behavior (excessive agreement with user challenges) or stubborn responses (rigid adherence to the …

Go to article

Website: Home, Zhiqu Lu, Likun Zhang, Lei Cao Aug 2026

Website: Home, Zhiqu Lu, Likun Zhang, Lei Cao

Gulf Research Program Data Sets

No abstract provided.

Go to article

Website: Latest Results, Zhiqu Lu, Likun Zhang, Lei Cao Aug 2026

Website: Latest Results, Zhiqu Lu, Likun Zhang, Lei Cao

Gulf Research Program Data Sets

No abstract provided.

Go to article

Website: News And Events, Zhiqu Lu, Likun Zhang, Lei Cao Aug 2026

Website: News And Events, Zhiqu Lu, Likun Zhang, Lei Cao

Gulf Research Program Data Sets

No abstract provided.

Go to article

Simulation And Delivery Of The Next Stage Of The Cebra Array, Hanna J. Ross Aug 2026

Simulation And Delivery Of The Next Stage Of The Cebra Array, Hanna J. Ross

Physics and Astronomy Summer Fellows

The CeBrA detector array at Florida State University’s Fox Lab uses a collection of CeBr3 scintillator detectors to collect gamma rays emitted by excited nuclear reaction products to gain information about nuclear energy levels of a nucleus of interest. When the array was commissioned, it contained five individual detectors. Expanding the array maximizes its efficiency and accuracy. In collaboration with FSU, Ursinus College has purchased nine additional detectors that will be added to the array at the end of the summer. While the detectors are still in our possession, we are working to create an accurate simulation model of …

Go to article

Scattering Phase Shift In Quantum Mechanics On Quantum Computers: Non-Hermitian Systems And Imaginary-Time Simulations, Peng Guo, Paul Levan, Frank Lee, Yong Zhao Aug 2026

Scattering Phase Shift In Quantum Mechanics On Quantum Computers: Non-Hermitian Systems And Imaginary-Time Simulations, Peng Guo, Paul Levan, Frank Lee, Yong Zhao

Research & Publications

To overcome the fast oscillatory behavior of correlation functions for extracting scattering phase shift in real-time quantum simulations encountered in the work of Guo et al. [Phys. Rev. D 113, 054512 (2026)], we propose and test two solutions in the present work. One is to simulate Hermitian systems in imaginary time, and the other is to simulate non-Hermitian systems in real time. We demonstrate that both approaches lead to the problem of nonunitary quantum evolution that can be solved by combining two quantum algorithms: block encoding and Hadamard test. The combined quantum algorithm does not require midcircuit …

Go to article

Effective Visibility In The Infrared Bands, Peter L. Dean-Erlander, Steven T. Fiorino, Ronald G. Driggers Aug 2026

Effective Visibility In The Infrared Bands, Peter L. Dean-Erlander, Steven T. Fiorino, Ronald G. Driggers

Faculty Publications

Visibility is an atmospheric metric for the comparison of terrestrial imaging conditions and locations. A limitation of visibility is that it is defined for the visible spectrum only, and there is no simple infrared equivalent. This study compares three reflective infrared wavebands: near-IR (NIR), shortwave IR (SWIR), and extended shortwave IR (eSWIR), to the visible band across a global set of cities to develop three rule-of-thumb functions for IR effective visibility. To accomplish this, a radiometric sensor model is combined with the Laser Environmental Effects Definition and Reference (LEEDR) software package to calculate the visibility of a black-and-white contrast target …

Go to article

Demonstrating Superresolution In Radar Range Estimation Using A Denoising Autoencoder, Robert Czupryniak, Abhishek Chakraborty, Andrew N. Jordan, John C. Howell Aug 2026

Demonstrating Superresolution In Radar Range Estimation Using A Denoising Autoencoder, Robert Czupryniak, Abhishek Chakraborty, Andrew N. Jordan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We apply machine learning methods to demonstrate radar range superresolution using a denoising autoencoder trained without supervision. Focusing on the estimation of a single physical parameter, the separation between two scatterers in the subwavelength regime, we constrain the network to a one-dimensional bottleneck layer with its size matched to the parameter dimensionality. We find that the bottleneck layer forms a reproducible, monotonic mapping with the true separation, showing that the network learns a low-dimensional representation directly aligned with the underlying physical parameter. We further show that this representation preserves the Fisher information of the signal, indicating that the network recovers …

Go to article

Single Fluorogens And Orientation-Localization Microscopy For Quantifying Chemical And Biomolecular Dynamics At The Nanoscale, Yiyang Chen, Yuanxin Qiu, Matthew D. Lew Aug 2026

Single Fluorogens And Orientation-Localization Microscopy For Quantifying Chemical And Biomolecular Dynamics At The Nanoscale, Yiyang Chen, Yuanxin Qiu, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Many chemical systems look uniform only because ensemble measurements average over their most interesting molecules. Electron-transfer rates vary across electrode surfaces; lipid membranes contain nanodomains with distinct packing and fluidity; peptide aggregates exhibit local polymorphism; and biomolecular condensates contain transient networks of interactions that are blurred in ensemble images. A central challenge in chemical imaging is not simply to see smaller structures, but to measure chemical variables such as polarity, redox potential, and molecular confinement at the single-molecule level. In this Account, we describe how fluorogens, molecules whose brightness, blinking, spectral shifts, orientation, rotational mobility, and motion are directly shaped …

Go to article

The Role Of Local Winds And A Semi-Persistent Coastal Front On The Diurnal Heat Budget In An Upwelling Bay, April P. Thibodeau, Ryan K. Walter, Piero L.F. Mazzini, Thomas P. Connolly, Christopher A. Edwards, Ian C. Robbins Aug 2026

The Role Of Local Winds And A Semi-Persistent Coastal Front On The Diurnal Heat Budget In An Upwelling Bay, April P. Thibodeau, Ryan K. Walter, Piero L.F. Mazzini, Thomas P. Connolly, Christopher A. Edwards, Ian C. Robbins

Physics

Coastal embayments in nearshore upwelling systems (“upwelling bays”) play a disproportionately large role in regional oceanography. In these systems, local diurnal wind forcing and thermal gradients associated with an upwelling shadow front that forms between warmer sheltered waters inside the bay and colder recently upwelled waters outside the bay strongly influence local temperature dynamics. Despite their importance to local ecosystems, there are no long-term studies that assess the heat budget inside upwelling bays. In this study, we analyzed approximately two years of water temperature throughout the water column using an autonomous profiler in a small upwelling bay in central California …

Go to article

Emergent De Sitter Expansion And Closed Topology From The Cosmic Fabric Model As An Open Thermodynamic System: Resolving The Negative Bulk Modulus Paradox, T G. Tenev, C B. Ward, T F. Tenev, M F. Horstemeyer Jul 2026

Emergent De Sitter Expansion And Closed Topology From The Cosmic Fabric Model As An Open Thermodynamic System: Resolving The Negative Bulk Modulus Paradox, T G. Tenev, C B. Ward, T F. Tenev, M F. Horstemeyer

Faculty Publications and Presentations

The Cosmic Fabric Model establishes a continuum-mechanics isomorphism to General Relativity by representing physical space as an elastic three-dimensional hyperplate embedded in a four-dimensional spatial bulk. Reproducing vacuum kinematics requires a vanishing P-wave modulus, which in turn implies a negative bulk modulus—an apparent thermodynamic instability in a closed system. This paradox is resolved by recasting the framework as an open system: the instability is not pathological but instead drives cosmic expansion. In this interpretation, the observable universe is a lower-energy solid formed through continuous solidification from a higher-dimensional precursor fluid. Using multiplicative kinematics from finite-growth mechanics, the model shows that …

Go to article

Developing And Testing Visualization Simulations For The Gamma-Ray Energy Tracking Array (Greta), Blake Mcnulty Jul 2026

Developing And Testing Visualization Simulations For The Gamma-Ray Energy Tracking Array (Greta), Blake Mcnulty

Physics and Astronomy Summer Fellows

GRETA is a recently-completed Department of Energy-funded project to construct an array of 120 gamma-ray detectors for use in nuclear physics experiments. The Gretina Array was the successful pilot project to construct 48 of the eventual 120 detectors that would be used in the array. UCGretina is a program that is used to simulate the GRETA array for the purposes of planning experiments and analyzing measurements. My job for this summer, with the advent of the full GRETA system, was to implement the new modular mounting structure for the full GRETA array in the simulation code. This involves creating the …

Go to article

Culmination Of The Arts And Stem To Enhance Creativity And Promote Learning, Kaleigh Evans Jul 2026

Culmination Of The Arts And Stem To Enhance Creativity And Promote Learning, Kaleigh Evans

Physics and Astronomy Summer Fellows

In this work, we investigate the results from a survey, issued to a course in “Stained Glass” (n= 23 students). Major findings include that the introduction of a problem-based learning (PBL) course in the arts of stained glass may support high demand skills such as interdisciplinary conceptual learning as well as soft skills such as scientific confidence, interdisciplinary transfer, and collaborative learnings. A journal paper draft was completed and will be submitted this Fall. This summer, work was also done to establish a guide to modeling and 3D printing to help establish and grow a makerspace on campus for use …

Go to article

Simulations Of Skyrmions And Merons, Ryan Friesen, Aidan Kirk, Tom Carroll, Xuemei Cheng Jul 2026

Simulations Of Skyrmions And Merons, Ryan Friesen, Aidan Kirk, Tom Carroll, Xuemei Cheng

Physics and Astronomy Summer Fellows

Skyrmions and merons are particle-like spin structures that are found in specific magnetic materials. Due to their stability and nanoscale size, these quasiparticles have been proposed as promising candidates for qubits in quantum computing applications. Our goal is to design materials that can host and stabilize these quasiparticles. Skyrmions and merons exist only under specific conditions, and the parameter space for these materials is vast. Thus, we use the simulation package MuMax3 to run simulations to test the viability of potential materials to simplify this search. We present on our simulations of these skyrmions and merons. This work was supported …

Go to article

Glassy Magnetic Freezing Of Interacting Clusters In Materials Related To The Lk-99 Family, Serafim Teknowijoyo, Domenico Napoletani, Vahan Nikoghosyan, Armen Gulian Jul 2026

Glassy Magnetic Freezing Of Interacting Clusters In Materials Related To The Lk-99 Family, Serafim Teknowijoyo, Domenico Napoletani, Vahan Nikoghosyan, Armen Gulian

Mathematics, Physics, and Computer Science Faculty Articles and Research

We report reproducible magnetization anomalies appearing below room temperature in copper-doped apatite materials belonging to the LK-99 family synthesized via hydrothermal methods. These anomalies are observed consistently across samples prepared under comparable conditions. Although the extracted Mydosh parameter lies within the range often associated with vortex-glass behavior in superconductors, a detailed analysis of DC magnetization, AC susceptibility, field dependence, and magnetic memory effects demonstrates that the observed phenomena are not related to superconductivity. Instead, the data are consistent with glassy magnetic freezing of interacting clusters. Compositional and structural analysis identifies covellite (CuS), one of the constituent phases in these multiphase …

Go to article

Global Time-Resolved Measurements Of Inlet/Isolator Unstart Induced By Mass Injection, Andrew N. Bustard, Benjamin L. Bemis, Aaron Marques, Matthew J. Zahr, Thomas J. Juliano Jul 2026

Global Time-Resolved Measurements Of Inlet/Isolator Unstart Induced By Mass Injection, Andrew N. Bustard, Benjamin L. Bemis, Aaron Marques, Matthew J. Zahr, Thomas J. Juliano

Publications

The inner surface pressure of an axisymmetric inlet/isolator model was measured using anodized-aluminum pressure-sensitive paint (PSP) viewing through cast acrylic. Temperaturesensitive paint was utilized to correct for the PSP’s temperature sensitivity. The model was tested under Mach 5.7 flow at 𝑹𝒆 = 7.1 ×106 /m under conventional noise conditions. Transverse jet injection with jet-to-inlet mass-flow ratios up to 0.8 was used to induce unstart in the inlet/isolator. Background-oriented schlieren visualization of the inlet shocks was collected simultaneously with the PSP to determine when the inlet unstarted. Computational fluid dynamics results were used to determine off-wall flow structures and quantify approach …

Go to article

Capturing An Electron In The Virtual State, Alok Nath Singh, Bibek Bhandari, Rafael Sánchez, Andrew N. Jordan Jul 2026

Capturing An Electron In The Virtual State, Alok Nath Singh, Bibek Bhandari, Rafael Sánchez, Andrew N. Jordan

Mathematics, Physics, and Computer Science Faculty Articles and Research

We address a foundational question in quantum mechanics: can a particle be directly found in a classically-forbidden virtual state? We instantiate this conceptual question by investigating the traversal of electrons through a tunnel barrier, which we define in a triple quantum dot system where the occupation of the central dot is energetically avoided. The motivation behind this setup is to answer whether the central dot is occupied or not during a virtual transition when it is being explicitly monitored. We investigate this problem in two different limits of continuous measurements: the stochastic quantum diffusion and the quantum jump. We find …

Go to article

Narrowband Searches For Continuous Gravitational Waves From Known Pulsars In The First Two Parts Of The Fourth Ligo–Virgo–Kagra Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Miriam Ramos Arevalo, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang Jul 2026

Narrowband Searches For Continuous Gravitational Waves From Known Pulsars In The First Two Parts Of The Fourth Ligo–Virgo–Kagra Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Miriam Ramos Arevalo, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

Rotating nonaxisymmetric neutron stars (NSs) are promising sources for continuous gravitational waves (CWs). CWs may, if detected, inform us about the internal structure and equation of state of NSs. Here, we present a narrowband search for CWs from known pulsars, for which a matched-filter search can be applied. Narrowband searches are robust to mismatches between electromagnetic (EM) and gravitational emissions, in contrast to fully targeted searches where they are assumed to be phase-locked. In this work, we search for the CW counterparts emitted by 34 pulsars using data from the first and second parts of the fourth LIGO–Virgo–KAGRA observing run. …

Go to article

Gwtc-4.0: Population Properties Of Merging Compact Binaries, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Wenhui Wang Jul 2026

Gwtc-4.0: Population Properties Of Merging Compact Binaries, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We detail the population properties of binary neutron star, neutron star–black hole binary, and binary black hole mergers using 158 events from the cumulative Gravitational-Wave Transient Catalog 4.0. The black hole primary mass distribution consists of a power-law-like continuum that steepens above 35 M⊙ with overdensities at 10 M⊙ and 35 M⊙. Binary black holes with primary masses near 10 M⊙ are more likely to have less massive secondaries, with a mass ratio distribution peaking at  q=0.74+0.13−0.13, potentially a signature of stable mass transfer during binary evolution. Black hole spins are inferred to be nonextremal, with …

Go to article

Coherent Two-Photon Backscattering And Induced Angular Quantum Correlations In Multiple-Scattered Two-Photon States Of The Light, Nooshin M. Estakhri, Theodore B. Norris Jul 2026

Coherent Two-Photon Backscattering And Induced Angular Quantum Correlations In Multiple-Scattered Two-Photon States Of The Light, Nooshin M. Estakhri, Theodore B. Norris

Engineering Faculty Articles and Research

We present the emergence of coherent two-photon backscattering, a manifestation of weak localization, in multiple scattering of maximally entangled pure and fully mixed two-photon states and examine the effect of entanglement and classical correlations. Quantum correlations in backscattering are investigated for finite three-dimensional disordered structures in the weak localization regime, as well as systems of a small number of scatterers with specified spatial arrangements. No assumptions are made about the statistical behavior of the scattering matrix elements. Furthermore, we study the interplay between quantum correlations induced by multiple scattering and the correlations that may be present in the illumination fields, …

Go to article

Interfacial Redox Mediation By Amine/Alkyne-Functionalized Silicon Nanoparticles: Surfactant-Free Gold Nanoparticle Synthesis, Amber L. Garcia, Brittany Griggs, Brian S. Mitchell, Mark J. Fink, Julie P. Vanegas Jul 2026

Interfacial Redox Mediation By Amine/Alkyne-Functionalized Silicon Nanoparticles: Surfactant-Free Gold Nanoparticle Synthesis, Amber L. Garcia, Brittany Griggs, Brian S. Mitchell, Mark J. Fink, Julie P. Vanegas

Physics & Astronomy Faculty Publications

We develop a surfactant-free synthesis method for gold nanoparticles (AuNPs) using 2-propynylamine-functionalized silicon nanoparticles as integrated redox-active supports. Surface-anchored amine groups act as built-in reducing sites for Au3+ precursors at the hexane–water interface under ambient conditions, enabling in situ AuNP nucleation and growth. Time-resolved UV-vis spectroscopy and dynamic light scattering track the emergence of plasmonic AuNPs, while quantitative morphology analysis reveals a final population dominated by spherical and near-spherical nanoparticles (∼74%), with faceted polyhedral structures (∼4%) and dendritic, hollow, irregular, and rod-like morphologies (∼22%) as minority species. The temporal evolution proceeds from early dendritic and irregular aggregates to a …

Go to article

Constraints On Gravitational Waves From The 2024 Vela Pulsar Glitch, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang Jul 2026

Constraints On Gravitational Waves From The 2024 Vela Pulsar Glitch, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang

Physics & Astronomy Faculty Publications

Among known neutron stars, the Vela pulsar is one of the best targets for gravitational-wave searches. It is also one of the most prolific in terms of glitches, which are sudden frequency changes in a pulsar’s rotation. Such glitches could cause a variety of transient gravitational-wave signals. Here, we search for signals associated with a Vela glitch on 2024 April 29 in data of the two LIGO detectors from the fourth LIGO–Virgo–KAGRA observing run. We search both for seconds-scale burst-like emission, primarily from fundamental (f-)mode oscillations, and for longer quasi-monochromatic transients up to 4 months in duration, primarily …

Go to article

Binding Energy Of Muonic Beryllium: Perturbative Versus All-Order Calculations, Shikha Rathi, Ulrich D. Jentschura, Paul Indelicato, Ben Ohayon Jun 2026

Binding Energy Of Muonic Beryllium: Perturbative Versus All-Order Calculations, Shikha Rathi, Ulrich D. Jentschura, Paul Indelicato, Ben Ohayon

Physics Faculty Research & Creative Works

We compute the ground-state binding energy of muonic (Formula presented) (Formula presented) Be in two ways: first, the fully perturbative treatment of the nuclear-size effect often employed in light systems, and second, an approach that accounts for the finite-nuclear-size to all orders (and is inspired by calculations otherwise employed for heavy muonic ions). The results are compared term by term and show that both approaches agree to better than one part-per-million of the total energy. The objective of this work is twofold. The first is practical: to provide a parameterization that allows the extraction of the (Formula presented) (Formula presented) …

Go to article

Frequency And Radiative Analysis Of Random Yagi-Uhf/Vhf Phased Array, Luis M. Bres, Luis A. Hernandez, Teviet Creighton Jun 2026

Frequency And Radiative Analysis Of Random Yagi-Uhf/Vhf Phased Array, Luis M. Bres, Luis A. Hernandez, Teviet Creighton

Physics & Astronomy Faculty Publications

This study investigates a phased array ground station capable of tracking multiple sources, multi-beamforming, electronic steering, easy scaling, and low cost. The project will develop a 20-pair dual-polarized Yagi-UHF/VHF phased array, comparing the parameters of random and uniform layouts. This study will be divided into two domains: frequency, and radiative domain. The frequency domain will explore the reception and transmission spectra analysis under several scenarios for our antennas. The radiative domain will explore the following: general side lobe analysis across both elevation and azimuth, antenna element sweep analysis, electronic beam steering analysis, electro-mechanical beam steering analysis, array density analysis, and …

Go to article

Long-Term Monitoring Of The Optical Performance Of The Primary Mirrors At The Coihueco And Loma Amarilla Sites Of The Pierre Auger Observatory, A. Abdul Halim, P. Abreu, M. Aglietta, M. Ahmed, I. Allekotte, K. Almeida Cheminant, B. Fick, K. Nguyen, D. Nitz, Et Al. Jun 2026

Long-Term Monitoring Of The Optical Performance Of The Primary Mirrors At The Coihueco And Loma Amarilla Sites Of The Pierre Auger Observatory, A. Abdul Halim, P. Abreu, M. Aglietta, M. Ahmed, I. Allekotte, K. Almeida Cheminant, B. Fick, K. Nguyen, D. Nitz, Et Al.

Michigan Tech Publications

This paper presents the results of an optical performance monitoring campaign for the primary mirrors installed in fluorescence telescopes at the Coihueco and Loma Amarilla sites at the Pierre Auger Observatory in Argentina. Since the end of 2003, this effort has developed into a unique long-term dataset that addresses the performance of the primary mirrors. We have focused on the scattering characteristics and specular reflectance of mirror segments, as well as their evolution over several years of operation. Despite being housed in climate-controlled buildings, dust accumulation, impurities, and natural aging — such as oxidation or other chemical or physical degradation …

Go to article

Using Galex Uv Excess To Search For Metal-Poor Halo Stars, Chase L. Smith, Maxwell Moe, Megan Frank, Raven Cilley, Javier Fregoso, Alexander Gleason, Grace Nelson, Et Al. Jun 2026

Using Galex Uv Excess To Search For Metal-Poor Halo Stars, Chase L. Smith, Maxwell Moe, Megan Frank, Raven Cilley, Javier Fregoso, Alexander Gleason, Grace Nelson, Et Al.

Michigan Tech Publications

Metal-poor solar-type stars display a significant reduction in metal-line blanketing at short wavelengths, leading to an excess of near-ultraviolet (NUV) flux compared to their metal-rich counterparts. We utilize Galaxy Evolution Explorer Satellite (GALEX) NUV and Gaia DR3 photometry along with ground-based spectroscopy to establish a correlation between NUV excess and [Fe/H]. We construct a sample of 492 solar-type (F5-G9) halo stars with NUV excess and measured metallicities. We perform our own observations with the KOSMOS spectrograph at Apache Point Observatory’s 3.5 m telescope to measure the abundances of 13 halo stars, 11 of which did not have previous metallicity measurements. …

Go to article

Ecological Insights From Field And Laboratory Studies Of Akashiwo Sanguinea, Alexis L. Pasulka, Matthew J. Harke, Jaden Hansen, Ryan K. Walter, Eva Kokkino Jun 2026

Ecological Insights From Field And Laboratory Studies Of Akashiwo Sanguinea, Alexis L. Pasulka, Matthew J. Harke, Jaden Hansen, Ryan K. Walter, Eva Kokkino

Physics

Blooms of the dinoflagellate Akashiwo sanguinea occur in coastal ecosystems worldwide and can have significant ecological consequences. Along the central California coast, long-term oceanographic and harmful algal bloom observations indicate that A. sanguinea has exhibited seasonal blooms since approximately 2017, coinciding with negative upwelling anomalies and warm, stratified conditions characteristic of late summer and early fall. In laboratory experiments, three A. sanguinea strains isolated from different sites and/or environmental conditions along the central California coast exhibited variation in growth rates, temperature sensitivity, and transcriptional responses. Under the conditions tested in this study, one strain exhibiting higher maximum growth rates and …

Go to article

Next Last