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Articles 301 - 330 of 8856

Full-Text Articles in Astrophysics and Astronomy

Investigating Long-Lasting Meteor Train Phenomena In Optical And Radio Regimes, Logan E. Cordonnier Jul 2025

Investigating Long-Lasting Meteor Train Phenomena In Optical And Radio Regimes, Logan E. Cordonnier

Physics & Astronomy ETDs

Throughout history, meteors have been regarded as fascinating and portentous events, with bygone astronomers diligently recording their occurrence. The research presented herein continues in this tradition, using modern instruments, software, and data reduction techniques to study long-lasting meteor trail phenomena, specifically in the optical (persistent trains; PTs) and radio (meteor radio afterglows; MRAs) regimes. The overarching goal was to investigate the similarities between these phenomena, which began with the creation of a PT catalog. Many of the prior assumptions about the nature of PTs were found to be unsubstantiated, and several new behaviors were uncovered. This includes the discovery of …


Detecting Ionospheric Disturbances Using High Frequency Coastal Radar Transmissions From The West Coast Of The United States, Riley N. Troyer, Kenneth Obenberger, Michael Negale, Eugene Dao, Zsolt Balint, Eric Burnside, Kris Robinson, Jeffrey M. Holmes, Pavel Inchin, Jonathan Snively Jul 2025

Detecting Ionospheric Disturbances Using High Frequency Coastal Radar Transmissions From The West Coast Of The United States, Riley N. Troyer, Kenneth Obenberger, Michael Negale, Eugene Dao, Zsolt Balint, Eric Burnside, Kris Robinson, Jeffrey M. Holmes, Pavel Inchin, Jonathan Snively

Space Dynamics Laboratory Publications

Coastal radar system are located around the world and many happen to transmit at frequencies capable of skywave propagation via the ionosphere. Therefore, they can be detected hundreds to thousands of kilometers away. This paper demonstrates the opportunity to detect 39 Coastal Ocean Dynamics Application Radar transmitters located on the western coast of the United States using three HF radio receivers in Utah and New Mexico. It also illustrates the possibility to use the phase and Doppler measurements of these signals to derive displacements of the refracting ionospheric layer up to meter resolution for the 2023 annular solar eclipse, an …


Hot Donors In Cataclysmic Variables: The Case Of Ei Psc, Jan Kára, S. Zharikov, M. Wolf, N. Vaidman, A. Agishev, S. Khokhlov, C. E. Chavez Jul 2025

Hot Donors In Cataclysmic Variables: The Case Of Ei Psc, Jan Kára, S. Zharikov, M. Wolf, N. Vaidman, A. Agishev, S. Khokhlov, C. E. Chavez

Physics & Astronomy Faculty Publications

Context. We present results of time-resolved optical spectroscopy and photometry of the short-orbital period dwarf nova EI Psc.

Aims. This study aims to determine fundamental system parameters of EI Psc, study properties of accretion structures in the system, and investigate its origin and current evolution state.

Methods. We analyse newly obtained time-resolved spectroscopic and photometric observations as well as archival data. We used light curve modelling, Doppler tomography, and MESA evolutionary models to study the characteristics of EI Psc.

Results. The system contains a relatively low temperature (Teff = 6130 K) white dwarf with mass of M …


Understanding Stellar Element Formation Through Nuclear Reactions, Irena Langer, Mally Panek, Kiyah Young-Wilson, Adam Fritsch Jul 2025

Understanding Stellar Element Formation Through Nuclear Reactions, Irena Langer, Mally Panek, Kiyah Young-Wilson, Adam Fritsch

Physics Student Scholarship

Studying nuclear structure has many applications, such as developing a stronger understanding of stellar nucleosynthesis, or how elements are formed inside of stars. Our research focuses on analysis of the proton evaporation nuclear reaction of Carbon-12 on Aluminum-27 in order to extract information about the structure of the nuclei involved. We are studying the cross section, or likelihood, of this reaction, using both experimental and modeled data. Since the cross section of a nuclear reaction depends on the physical characteristics of the nuclei involved, we can use the cross section to analyze our work.


Auroral Hemispheric Power Asymmetry During Geomagnetic Storms: A Multi-Database Investigation Using Ae And Supermag Indices, Melvin J. Reyes Lozada Jun 2025

Auroral Hemispheric Power Asymmetry During Geomagnetic Storms: A Multi-Database Investigation Using Ae And Supermag Indices, Melvin J. Reyes Lozada

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Engineering at Morehead State University in partial fulfillment of the requirements for the Degree Master of Science by Melvin J. Reyes Lozada on June 20, 2025.


Exploring The Very Early Cosmological History With Dark Matter And Primordial Black Holes, Phuc Duc Loc Ngo Jun 2025

Exploring The Very Early Cosmological History With Dark Matter And Primordial Black Holes, Phuc Duc Loc Ngo

Physics & Astronomy ETDs

We explore the possibilities of nonstandard early cosmological histories and their potential roles to explain DM. We study how particle DM is produced with scenarios of early matter domination (EMD), how primordial black holes (PBHs), which could also be a DM candidate in certain mass ranges, are formed with enhanced curvature perturbation or FOPT and the corresponding gravitational wave (GW) signals, how PBHs could increase their mass by accretion during EMD and the corresponding GW signals.


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 …


Study Of Agn Jet And Possible Connection Among Different Agn Classes, Shahjahan Iqbal Jun 2025

Study Of Agn Jet And Possible Connection Among Different Agn Classes, Shahjahan Iqbal

University Departments

No abstract provided.


Spin Precession In Magnetized Kerr Spacetime, Karthik Krishnamurthy Iyer Jun 2025

Spin Precession In Magnetized Kerr Spacetime, Karthik Krishnamurthy Iyer

University Departments

No abstract provided.


Interacting Galaxy Clusters As A Probe To Cosmic Filaments, Shreya R. Kamath Jun 2025

Interacting Galaxy Clusters As A Probe To Cosmic Filaments, Shreya R. Kamath

University Departments

No abstract provided.


Photometric And Spectroscopic Properties Of Hydrogen-Rich Supernovae, Chaitrika B. M Jun 2025

Photometric And Spectroscopic Properties Of Hydrogen-Rich Supernovae, Chaitrika B. M

University Departments

No abstract provided.


Probing Dust Grain Optical Properties In The Ism Using Diffuse Ultraviolet Observations Together With Radiative Transfer Modelling, Nilanjana Dey Choudhury Jun 2025

Probing Dust Grain Optical Properties In The Ism Using Diffuse Ultraviolet Observations Together With Radiative Transfer Modelling, Nilanjana Dey Choudhury

University Departments

No abstract provided.


Higher-Order Exceptional Points In A Non-Reciprocal Waveguide Beam Splitter, Hamed Ghaemidizicheh, Shahram Dehdashti, Andreas Hanke, Ahmed Touhami, Janis Nötzel Jun 2025

Higher-Order Exceptional Points In A Non-Reciprocal Waveguide Beam Splitter, Hamed Ghaemidizicheh, Shahram Dehdashti, Andreas Hanke, Ahmed Touhami, Janis Nötzel

Physics & Astronomy Faculty Publications

Non-Hermitian systems have attracted significant interest because of their intriguing properties, including exceptional points (EPs), where eigenvalues and the corresponding eigenstates coalesce. In particular, quantum systems with EPs exhibit an enhanced sensitivity to external perturbations, which increases with the order of the EP. Therefore, higher-order EPs hold significant potential for advanced sensing applications, but they are challenging to achieve due to stringent symmetry requirements. In this work, we study the dynamics of a generalized lossy waveguide beam splitter with asymmetric coupling by introducing non-reciprocity as a tunable parameter to achieve higher-order EPs even without dissipation. Moreover, we analyze the evolution …


Data Sonification: The Art Of Exploring Space Through Sound, Jessica Cotturone Jun 2025

Data Sonification: The Art Of Exploring Space Through Sound, Jessica Cotturone

Music: Student Scholarship & Creative Works

Data sonification is a cutting-edge, interdisciplinary field that involves the transformation of data into sound. As the amount of data collected in today’s world continues to rise exponentially, new collaborations between scientists, mathematicians, and musicians are exploring the potential applications of sonification. Turning data into sound can create new avenues for interpretation and can increase accessibility for visually-impaired populations. The sonic renderings produced by this practice exist on a spectrum from sound to music and vary in their levels of objectivity and expressivity. One of the major areas where data sonification is providing a new scientific and artistic perspective is …


Temperature, Albedo, And Emissivity Of Triton And Proteus From Voyager 2 Iris Data, Garrett Nobis, Vincent Chevrier Jun 2025

Temperature, Albedo, And Emissivity Of Triton And Proteus From Voyager 2 Iris Data, Garrett Nobis, Vincent Chevrier

Space and Planetary Science Faculty Publications and Presentations

The Voyager 2 infrared interferometer and spectrometer (IRIS) spectra for Triton are revisited, and the Proteus IRIS spectra are looked at for the first time. Fifty more spectra are added to the average of 16 previously used for Triton. The unit emissivity Planck function temperature result is 37.9  ±  0.5 K. Iterating IRIS temperatures over several emissivities allows for constraints on emissivity and Bond albedo based on past data. Upper and lower bounds on Triton’s temperature and albedo of 37.9  ±  0.5 to 46.1  ±  0.7 K for temperature and 0.67−0.86 for albedo are determined from the IRIS data and …


Artificial Intelligence And Astronomy: Lab Manual For Generative Ai-Based Learning Activities, Vasiliy Znamenskiy Jun 2025

Artificial Intelligence And Astronomy: Lab Manual For Generative Ai-Based Learning Activities, Vasiliy Znamenskiy

Open Educational Resources

This lab manual introduces community college students to the intersection of artificial intelligence (AI) and astronomy through hands-on, inquiry-based activities. It explores how generative AI platforms—ranging from text-based chat systems to image and video generators—can enhance scientific understanding, creativity, and critical thinking in space science education. Students engage with tools such as ChatGPT, Gemini, DALL·E, and Synthesia to formulate and evaluate astronomy-related questions, generate scientifically inspired visualizations, and produce dynamic representations of cosmic phenomena. Through structured exercises, the manual promotes digital literacy, fosters analytical skills, and illustrates how AI assists in astronomical research, including data analysis, image enhancement, spacecraft autonomy, …


Atomistic Characterization Of Hydration-Dependent Fuel Cell Ionomer Nanostructure: Validation By Vibrational Spectroscopy, Dan J. Donnelly, Moon Young Yang, Nicholas Dimakis, Seung Soon Jang, William A. Goddard Iii, Eugene S. Smotkin Jun 2025

Atomistic Characterization Of Hydration-Dependent Fuel Cell Ionomer Nanostructure: Validation By Vibrational Spectroscopy, Dan J. Donnelly, Moon Young Yang, Nicholas Dimakis, Seung Soon Jang, William A. Goddard Iii, Eugene S. Smotkin

Physics & Astronomy Faculty Publications

The development of Nafion alternatives for fuel cells and electrolyzers requires a fundamental understanding of hydration-dependent ion-exchange site acid/base chemistry. We present here reactive force field (ReaxFF) molecular dynamics (MD) simulations of Nafion at varying molar water/ion-exchange-site ratios (λ), which we correlate to our experimental and density functional theory-based vibrational spectra. ReaxFF describes the formation and breaking of covalent bonds, enabling simulations of proton exchange between sulfonic acid/sulfonate groups and water/hydronium. Our MD simulations determine the λ-dependent equilibrium proportions of protonated and deprotonated sites. We find that protonated sites persist across all λ from 0 to 20, challenging the widely …


Gnss Technology, Utah State University Space Dynamics Laboratory Jun 2025

Gnss Technology, Utah State University Space Dynamics Laboratory

Space Dynamics Laboratory Publications

SDL presentation on GNSS Technology


Using Oblique, Bistatic Receptions Of Superdarn Signals To Measure Hf Propagation In The Auroral And Polar Cap Region, Riley Troyer, Jeffrey Holmes, Evan Thomas, Simon Shepherd, Eugene Dao, John Carilli Jun 2025

Using Oblique, Bistatic Receptions Of Superdarn Signals To Measure Hf Propagation In The Auroral And Polar Cap Region, Riley Troyer, Jeffrey Holmes, Evan Thomas, Simon Shepherd, Eugene Dao, John Carilli

Space Dynamics Laboratory Publications

Experiment Geometry

Three receiver locations:

  • Pituffik (formerly Thule)
  • Utqiagvik (formerly Barrow)
  • USCGC Healy – Beaufort Sea

Two SuperDARN locations:

  • Christmas Valley (CVE, CVW)
  • Iceland (ICE, ICW)


Wide Binary Orbits Are Preferentially Aligned With The Orbits Of Small Planets, But Probably Not Hot Jupiters, S. Christian, A. Vanderburg, J. Becker, A. L. Kraus, L. Pearce, K. A. Collins, M. Rice, Eric L.N. Jensen, D. Baker, V. Bozza, P. Benni, A. Bieryla, A. Binnenfeld, K. I. Collins, D. M. Conti, I. J. M. Crossfield, P. Evans, M. C. Johnson, E. Girardin, J. Gregorio, P. Lewin, T. Mazeh, F. Murgas, A. Panahi, F. J. Pozuelos, D. J. Radford, H. M. Relles, F. Rodriguez Frustaglia, R. P. Schwarz, G. Srdoc, C. Stockdale, T.-G. Tan, W. C. Waalkes, G. Wang, J. Wittrock, S. Zucker Jun 2025

Wide Binary Orbits Are Preferentially Aligned With The Orbits Of Small Planets, But Probably Not Hot Jupiters, S. Christian, A. Vanderburg, J. Becker, A. L. Kraus, L. Pearce, K. A. Collins, M. Rice, Eric L.N. Jensen, D. Baker, V. Bozza, P. Benni, A. Bieryla, A. Binnenfeld, K. I. Collins, D. M. Conti, I. J. M. Crossfield, P. Evans, M. C. Johnson, E. Girardin, J. Gregorio, P. Lewin, T. Mazeh, F. Murgas, A. Panahi, F. J. Pozuelos, D. J. Radford, H. M. Relles, F. Rodriguez Frustaglia, R. P. Schwarz, G. Srdoc, C. Stockdale, T.-G. Tan, W. C. Waalkes, G. Wang, J. Wittrock, S. Zucker

Physics & Astronomy Faculty Works

Studying the relative orientations of the orbits of exoplanets and wide-orbiting binary companions (semimajor axis greater than 100 au) can shed light on how planets form and evolve in binary systems. Previous observations by multiple groups discovered a possible alignment between the orbits of visual binaries and the exoplanets that reside in them. In this study, using data from Gaia DR3 and TESS, we confirm the existence of an alignment between the orbits of small planets (R < 6 R⊕) and binary systems with semimajor axes below 700 au (p = 10⁻⁶). However, we find no statistical evidence …


Integrating Universal Generative Ai Platforms In Educational Labs To Foster Critical Thinking And Digital Literacy, Vasiliy S. Znamenskiy, Joel Hernandez, Rafael Niyazov Jun 2025

Integrating Universal Generative Ai Platforms In Educational Labs To Foster Critical Thinking And Digital Literacy, Vasiliy S. Znamenskiy, Joel Hernandez, Rafael Niyazov

Publications and Research

This study investigates the educational potential of generative artificial intelligence (GenAI) platforms based on large language models (LLMs), such as ChatGPT, Claude, and Gemini, as tools for studentcentred learning. Recognizing the current limitations of GenAI, particularly its propensity for generating inaccurate or misleading information—the paper proposes a novel instructional strategy: an interdisciplinary laboratory designed to foster critical evaluation of GenAI-generated outputs. In this pedagogical model, students engage with GenAI systems by posing questions or solving problems drawn from topics they have already studied and understand. Equipped with correct answers, students are positioned to assess the accuracy and relevance of AI-generated …


The Gauge/Gravity Holographic Duality Between String Theory And Quantum Field Theory: A Full Introduction, Alex A. Short Jun 2025

The Gauge/Gravity Holographic Duality Between String Theory And Quantum Field Theory: A Full Introduction, Alex A. Short

Physics

The Anti-deSitter Spacetime / Conformal Field Theory (AdS/CFT) correspondence is a well known holographic duality between ten dimensional superstring theories and conformal quantum field theories. The existence of such a correspondence is fascinating and the duality provides a powerful tool-set for working out problems in both string theory and quantum field theory. The correspondence defines a dictionary of terms that exist dual to one another in each theory, allowing theorists to understand the dynamics in one system based on quantities from another. Furthermore, when one side of the duality has strong coupling (meaning the approximations of perturbation theory are no …


Search For Gravitational Waves Emitted From Sn 2023ixf, A. G. Abac, R. Abbott, Teviet Creighton, Mario C. Diaz, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Wenhui Wang Jun 2025

Search For Gravitational Waves Emitted From Sn 2023ixf, A. G. Abac, R. Abbott, Teviet Creighton, Mario C. Diaz, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We present the results of a search for gravitational-wave transients associated with core-collapse supernova SN 2023ixf, which was observed in the galaxy Messier 101 via optical emission on 2023 May 19, during the LIGO–Virgo–KAGRA 15th Engineering Run. We define a five-day on-source window during which an accompanying gravitational-wave signal may have occurred. No gravitational waves have been identified in data when at least two gravitational-wave observatories were operating, which covered ∼14% of this five-day window. We report the search detection efficiency for various possible gravitational-wave emission models. Considering the distance to M101 (6.7 Mpc), we derive constraints on the gravitational-wave …


Exploring The Enstatite Chondrites: Modal Abundances, Metamorphic History, And Volatile Challenges, Mabel Gray Jun 2025

Exploring The Enstatite Chondrites: Modal Abundances, Metamorphic History, And Volatile Challenges, Mabel Gray

Dissertations, Theses, and Capstone Projects

This thesis investigates the formation conditions, thermal histories, and volatile inventories of enstatite chondrites (ECs). A diverse set of ECs is analyzed to capture the broad variability within this meteorite class. Chapter 1 presents a comparative analysis of mineral abundances using automated point counting, X-ray diffraction analysis, and XMapTools-based phase mapping. The results reveal significant variations in silicate and sulfide abundances across EC groups, challenging the conventional binary classification and suggesting distinct formation conditions. Chapter 2 explores the thermal histories of two highly equilibrated EH chondrites, proposing a novel formation mechanism on the parent asteroid: contact metamorphism driven by an …


Streaming Instabilities In Class 0/I Disks, Shirin Gul Zaidi Jun 2025

Streaming Instabilities In Class 0/I Disks, Shirin Gul Zaidi

Dissertations, Theses, and Capstone Projects

While it is clear that planets form in protoplanetary disks, fragmentation and the radial drift of pebbles inhibit the growth of grains to planetesimals. To overcome these barriers, effective localized dust clumping on a short enough time scale is required. One promising solution to this problem is the streaming instability. Streaming instability is only triggered with a large enough dust-to-gas ratio and grain size. Though it is unknown when and where those conditions are met in protoplanetary disks, recent studies have indicated that planetary cores likely require early formation to match detected exoplanet system masses, so that we need to …


Fast Transients From Magnetic Disks Around Non-Spinning Collapsar Black Holes, Justin A. Bopp Jun 2025

Fast Transients From Magnetic Disks Around Non-Spinning Collapsar Black Holes, Justin A. Bopp

Dissertations, Theses, and Capstone Projects

Most black holes (BHs) formed in collapsing stars have low spin, though some are expected to acquire a magnetic accretion disk during the collapse. While such BH disks can launch magnetically driven winds, their physics and observational signatures have remained unexplored. We present global 3D general relativistic magnetohydrodynamic simulations of collapsing stars that form slowly spinning BHs with accretion disks. As the disk transitions to a magnetically arrested state, it drives mildly relativistic, wobbling, collimated magnetic outflows through two mechanisms: steady outflows along vertical magnetic field lines (“Blandford-Payne jets”) and magnetic flux eruptions. With isotropic-equivalent energy of Eiso ≈10 …


Artificial Intelligence And Astronomy: Lab Manual For Generative Ai-Based Learning Activities, Vasiliy Znamenskiy May 2025

Artificial Intelligence And Astronomy: Lab Manual For Generative Ai-Based Learning Activities, Vasiliy Znamenskiy

Open Educational Resources

This laboratory manual introduces an innovative approach to teaching astronomy by integrating generative artificial intelligence (AI) tools into hands-on educational activities. Aimed at undergraduate and general education students, the manual guides learners through interactive exercises that involve evaluating AI-generated text responses, creating scientifically inspired images, and producing short educational videos about astronomical phenomena. By engaging with platforms such as ChatGPT, Gemini, DALL·E, and InVideo, students develop critical thinking skills, enhance their digital literacy, and deepen their understanding of space science. The method emphasizes inquiry-based learning, creativity, and scientific communication, preparing students to become thoughtful users of AI in academic and …


Near-Earth Object (Neo) Surveyor Introduction “Neos”, Brent Carlsen May 2025

Near-Earth Object (Neo) Surveyor Introduction “Neos”, Brent Carlsen

Space Dynamics Laboratory Publications

NEOS

- Near-Earth Object Surveyor (NEOS)

- Its Mission

- Its Importance

- How it’s built

- What you will see today

  • Where piece parts were made
  • Where it will be assembled
  • Where it will be tested


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.


A Catalytic Pathway For The Formation Of Cyanobenzene In Nitrogen-Rich Environments And The Spectroscopy Of The Reactive Intermediates, Vincent J. Esposito, Silvia Alessandrini, David Dubois, Ryan Fortenberry May 2025

A Catalytic Pathway For The Formation Of Cyanobenzene In Nitrogen-Rich Environments And The Spectroscopy Of The Reactive Intermediates, Vincent J. Esposito, Silvia Alessandrini, David Dubois, Ryan Fortenberry

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The catalytic reaction of isocyanobenzene (C6H5NC) with NCN− produces cyanobenzene (C6H5NC) through various highly stable reactive intermediate species. Nitrogen-rich environments such as Titan’s atmosphere serve as favorable locations to study reaction pathways involving nitrogenated species contributing to organic growth. Formation pathways of cyanobenzene have been characterized, but none with the contribution of anions or phenyl groups. In regions with a high abundance of nitrogen anions, such as Titan’s atmosphere, reactions with species such as NCN− may play a role in the formation of cyanobenzene. Highly accurate computational methods are used …