Digital Commons Network^™

A Uniform Analysis Of Gas-Phase Metallicity Evolution With 1–3 Gyr Time Sampling Over The Past 12 Gyr, Shweta Jain, Ryan L. Sanders, Ali Ahmad Khostova, Tucker Jones, Alice E. Shapley, Naveen Reddy, Alex M. Garcia, Paul Torrey, Alison L. Coil

Physics and Astronomy Faculty Publications

We present a systematic investigation of the evolution of the mass–metallicity relation (MZR) and fundamental metallicity relation (FMR) using uniform metallicity diagnostics across redshifts z ∼ 0 to z ∼ 3.3. We present new Keck/Deep Imaging Multi-Object Spectrograph measurements of the [O II]λλ3726, 3729 emission line doublet for star-forming galaxies at z ∼ 1.5 with existing measurements of redder rest-optical lines from the MOSFIRE Deep Evolution Field survey. These new observations enable uniform estimation of the gas-phase oxygen abundance using ratios of the [O II], Hβ, and [O III] lines for mass-binned samples of star-forming galaxies …

Energy Levels Of Multiscale Bound States From Qed Energy-Momentum Trace, Michael I. Eides, Vladimir A. Yerokhin

Physics and Astronomy Faculty Publications

Energy levels of quantum electrodynamics (QED) bound states, which depend on a number of independent mass parameters, can be calculated as matrix elements of the QED energy-momentum tensor trace. As an example of such system we consider muonic hydrogen. The leading one-loop corrections to its energy levels depend on the electron and muon masses. These corrections are calculated as matrix elements of the energy-momentum tensor trace. Respective one-loop trace diagrams are different from the standard Lamb shift diagrams. We explain analytically and diagrammatically why two different sets of diagrams lead to the same results. Similar relationships should also hold beyond …

Fe Xviii–Xxiv Kβ Inner-Shell Absorption Lines In The X-Ray Spectra Of Neutron Star And Black Hole Binaries With Xrism, Masahiro Tsujimoto, Daiki Miura, Hiroya Yamaguchi, Ehud Behar, Chris Done, María Díaz Trigo, Chamani M. Gunasekera, Peter A. M. Van Hoof, Stefano Bianchi, Maryam Dehghanian, Gary J. Ferland

Physics and Astronomy Faculty Publications

The advent of the X-ray microcalorimeter spectrometer Resolve onboard the XRISM space telescope opened a new era for high-resolution X-ray spectroscopy of astrophysical plasmas. Many spectral features were newly detected, including the Kα and Kβ inner-shell transition lines of mildly ionized (F- to Li-like) Fe at 6–8 keV in the spectra of X-ray binaries and active galactic nuclei. The widely used atomic databases contain information on the Kα but not Kβ lines of these ions. We conducted the atomic structure calculation using FAC to derive the Fe Kα and Kβ lines and verified the …

Pull-Out Performance Of Multiple Glued-In Rods In Sustainable Inorganic-Bonded Bamboo Composite Under Perpendicular-To-Grain Loading, Jing Ru Yao, Shaohua Yu, Qingxia Yue, Hanshu Zhang, Ernian Zhao

Physics and Engineering Science

As a sustainable bio-based material derived from bamboo crops, inorganic-bonded bamboo composite (InorgBam) exhibits excellent environmental sustainability, fire resistance, and long-term durability. To enable its broader adoption in structural applications, robust and efficient connection methods are essential. Glued-in rod (GiR) connections, characterized by high strength, stiffness, and superior fire performance, are especially well-suited for modern engineered bamboo and timber connections. The pull-out behavior of multiple GiRs in InorgBam material under perpendicular-to-grain loading was experimentally investigated using double-, triple-, and quadruple-rod specimens. The influence of anchorage length and spacing on failure modes and load-carrying capacity was systematically analyzed. Results demonstrate that …

A Novel Simulation Framework To Estimate Dynamic Response Of A Solar Panel Array Under Stationary Stochastic Wind Loads, Hanshu Zhang, You Jia Li, Matthew J. Dejong

Physics and Engineering Science

This paper presents a novel simulation framework for estimating the dynamic response of a full-scale ground-mounted solar panel array under stationary wind loads that are spatially correlated across the length of the solar panel array. Specifically, the framework uses mean pressure coefficient distributions along the length of a 1:10 prototype scale of the solar panel array from smooth inflow derived using the computational fluid dynamics (CFD) simulation software The Wind Engineering with Uncertainty Quantification (WE-UQ). Note that for the CFD simulation, the input wind field across the length of the solar panel array is uniform along the horizontal direction, and …

Preliminary Observations From The Relativistic Electron Atmospheric Loss (Real) Satellite Mission, Evzen Selvon, Robyn Millan

Wetterhahn Science Symposium Posters

The Relativistic Electron Atmospheric Loss (REAL) spacecraft (launched in July 2025) is a 3U cubesat designed to measure the precise energies (1 keV – 2MeV) and pitch angles of electrons entering the Earth’s ionosphere. The mission involves Dartmouth, BU, JHUAPL, MSU, and NASA. REAL carries three particle sensors measuring low, medium, and high energies. This work is focused on the ElectroStatic Analyzer (ESA) instrument, designed to measure lower energy electrons (1-40 keV) in the directions parallel and perpendicular to the Earth’s magnetic field. This research aims to identify notable events observed by the REAL spacecraft for future analysis.

An Exploration Of Geomagnetically Induced Currents And The Accessibility Of Geomagnetic Data Collection, Richard Le

Physics Theses

Geomagnetically Induced Currents (GICs) are electrical currents induced in long grounded conductors during geomagnetic disturbances. They represent one of the primary space weather hazards to critical infrastructure, particularly high-voltage power transmission systems and other grounded conductor networks such as pipelines. As modern society becomes more dependent on these systems, understanding and mitigating the impacts of space weather has become increasingly important. This thesis examines the physical mechanisms that generate GICs, from the interaction of the solar wind with Earth’s Magnetosphere to Magnetosphere-Ionosphere-Thermosphere (MIT) coupling and the current systems that drive geomagnetic disturbances (GMDs). Case studies from Zimbabwe and Finland illustrate …

Computational Study Of Rotating Detonation Combustors, Aditya Balasubramaniam

Mechanical and Aerospace Engineering Theses

Rotating detonation combustors (RDCs) are pressure-gain combustion devices that sustain one or more continuously rotating detonation waves, offering potential thermodynamic and performance advantages over conventional deflagration-based systems. Their behavior depends strongly on combustor geometry and operating conditions. Understanding these effects is therefore essential for the design and optimization of practical RDCs. Accordingly, this thesis numerically investigates annular RDCs with two primary objectives: (1) to evaluate the effects of propellant mass flux and (2) to assess the influence of annular width on detonation-wave dynamics and combustor performance.

A finite-volume framework is used to solve the compressible reactive Euler equations with hydrogen–air …

The Hitran2024 Molecular Spectroscopic Database, I. E. Gordon, L. S. Rothman, R. J. Hargreaves, F. M. Gomez, T. Bertin, C. Hill, R. V. Kochanov, Y. Tan, P. Wcisło, V. Yu. Makhnev, P. F. Bernath, M. Birk, V. Boudon, A. Campargue, A. Coustenis, B. J. Drouin, R. R. Gamache, J. T. Hodges, D. Jacquemart, E. J. Mlawer, A. V. Nikitin, V. I. Perevalov, M. Rotger, S. Robert, J. Tennyson, G. C. Toon, H. Tran, V. G. Tyuterev, E. M. Adkins, A. Barbe, D. M. Bailey, K. Bielska, L. Bizzocchi, T. A. Blake, C. A. Bowesman, P. Cacciani, P. Čermák, A. G. Császár, L. Denis, S. C. Egbert, O. Egorov, A. Yu. Ermilov, A. J. Fleisher, H. Fleurbaey, A. Foltynowicz, T. Furtenbacher, M. Germann, E. R. Guest, J. J. Harrison, J. -M. Hartmann, A. Hjältén, S. -M. Hu, X. Huang, T. J. Johnson, H. Jóźwiak, S. Kassi, M. V. Khan, F. Kwabia-Tchana, T. J. Lee, D. Lisak, A. -W. Liu, O. M. Lyulin, N. A. Malarich, L. Manceron, A. A. Marinina, S. T. Massie, J. Mascio, E. S. Medvedev, V. V. Meshkov, G. Ch. Mellau, M. Melosso, S. N. Mikhailenko, D. Mondelain, H.S.P. Müller, M. O' Donnell, A. Owens, A. Perrin, O. L. Polyansky, P. L. Raston, Z. D. Reed, M. Rey, C. Richard, G. B. Rieker, C. Röske, S. W. Sharpe, E. Starikova, N. Stolarczyk, A. V. Stolyarov, K. Sung, F. Tamassia, J. Terragni, V. G. Ushakov, S. Vasilchenko, B. Vispoel, K. L. Vodopyanov, G. Wagner, S. Wójtewicz, S. N. Yurchenko, N. F. Zobov

Chemistry & Biochemistry Faculty Publications

The HITRAN database is a curated compilation of validated molecular spectroscopic parameters, established in the early 1970s. It is used by various computer codes to predict and simulate the transmission and emission of light in gaseous media (with an emphasis on terrestrial and planetary atmospheres). The HITRAN compilation is composed of six major components. These components include the line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, experimentally derived absorption cross-sections (for molecules where it is not yet feasible for representation in a line-by-line form), collision-induced absorption data, aerosol indices of refraction, and general tables (including partition sums) that apply globally …

References, Appendices & All Parts Merged, Konstantin Likharev

Essential Graduate Physics

Includes: Appendix MA: Selected Mathematical Formulas; Appendix UCA: Selected Physical Units and Constants; References; EGP merged file (all parts, appendices, and references)

The Scattering Algebra Of Physical Space: Squared Massive Constructive Amplitudes, Moab Croft, Neil Christensen

Faculty publications – Physics

The Algebra of Physical Space (APS) is used to explore the Constructive Standard Model (CSM) of particle physics. Namely, this paper connects the spinor formalism of the APS to massive amplitudes in the CSM. A novel equivalency between traditional CSM and APS-CSM formalisms is introduced, called the Scattering Algebra (SA), with example calculations confirming the consistency of results between both frameworks. Through this all, two significant insights are revealed: The identification of traditional CSM spin spinors with Lorentz rotors in the APS, and the connection of the CSM to various formalisms through ray spinor structure. The CSM’s results are …

Amorphous Selenium Photodetectors For Liquid Noble Detectors, Michael Rooks

Physics Dissertations - Archive

Physics offers a way to connect deeply with the mysteries that surround us. Advances in detector physics, particularly in neutrino experiments and rare-event searches, have expanded our ability to probe phenomena that challenge how we describe the universe. Each discovery brings us closer to understanding the unknown, returning us to a sense of wonder that motivates exploration. My work on detector technology was inspired by a concept paper from Professor David Nygren, in which he noted the speculative possibility of integrating photon detection into a charge readout for pixelated liquid argon time projection chambers (LArTPCs) using the photoconductor amorphous selenium …

Wiener-Granger Causality To Model Banking Sector Contagion, Riya Bhasin

CMC Senior Theses

In this thesis, we explore the main drivers behind the 2008 Global Financial Crisis and how the interconnectivity of banking sectors contributed to the worldwide spread of its effects. To understand how this became a global phenomenon, we apply linear Wiener-Granger Causality as a form of network analysis, building on pre-existing methodology in order to study continent banking indices. We find connections across locales on the continent and country level, but ones that are weak. Our modelling was insufficient to completely capture existing and well-known relationships accurately. This occurs due to limitations of the data and of the linear models’ …

Part Sm: Statistical Mechanics, Konstantin Likharev

Essential Graduate Physics

Includes: Review of Thermodynamics; Principles of Physical Statistics; Ideal and Not-So-Ideal Gases; Phase Transitions; Fluctuations; Elements of Kinetics

Laser Beam Shaping Using A Neural Network, Azeem A. Hakim

Honors Undergraduate Theses

Multiphoton lithography (MPL) is a method of laser-based 3D-printing for fabricating micron-scale structures point-by-point in a photopolymerizable medium. MPL’s high-resolution capabilities have made it a powerful method for the fabrication of many devices, such as microelectromechanical systems (MEMS) and tissue scaffolds.  The throughput of MPL processes can be increased by using spatially shaped laser beams that expose large areas or volumes simultaneously. A laser beam can be reshaped by passing it through a spatial light modulator (SLM) displaying a pre-designed phase mask. One type of laser beam profile used for this purpose is the Bessel beam, a type of structured …

Ultrafast Vibrational Dynamics In Important Wide-Bandgap Semiconductors, Dielectrics And Energetic Materials, Dinusha Madushanka Senarathna

Open Access Dissertations

This dissertation applies time-resolved coherent anti-Stokes Raman scattering (tr-CARS), to measure ultrafast vibrational dynamics in technologically important solid-state and van der Waals molecular systems. The central goal is to use time-domain Raman methods to resolve mode-specific phonon and vibrational dephasing processes with high temporal precision, high spectral selectivity, and sufficient experimental flexibility to probe materials ranging from wide-bandgap semiconductors and oxide crystals to energetic molecular crystals. Across the work, I show that carefully designed tr-CARS measurements can access vibrational lifetimes from hundreds of femtoseconds to several picoseconds, enabling direct observation of decay pathways, relaxation mechanisms, and dispersion effects that shape …

Utilizing Computer Modeling To Optimize Electric Fields Within Xenon Time Projection Chambers, Miles Meloni

Honors Theses

XENONnT is a physics experiment designed with the goal of detecting dark matter particles. The detector is a time projection chamber; a series of charged electrodes creates an electric field, surrounding a central body filled with liquid and gaseous xenon. Photomultiplier tubes (PMTs), positioned on either end of the chamber, serve to detect light signals. We seek to minimize the root mean square of the electric field norms experienced by the PMTs. This quantity corresponds to the variance in the electric field observed by the PMTs. Establishing a consistent electric field is important to maintaining these sensitive components. The electric …

Ultra-Low Noise Ion Detection For Neutrinoless Double Beta Decay Searches, Karen E. Navarro

Physics Dissertations

Neutrinos are the most abundant particles in the universe that carry mass. Yet, we know very little about them since they are electrically neutral and interact weakly. A small instance after the Big Bang, an imbalance occurred that caused matter to be produced in greater quantities than antimatter. A leading candidate for this unexplained process is leptogenesis. Leptogenesis predicts that neutrinos are Majorana particles: a particle that is its own antiparticle. Today, particle detectors are being constructed to search for this property through the yet unobserved neutrinoless double beta decay (0νββ) . If observed, this would demonstrate that neutrinos are …

Bursty Bulk Flows: The What, The Why, And Their Impacts On The Earth, Fariza Tanvir

2026 Spring Honors Capstones Projects

Due to solar wind-magnetosphere interactions, the Earth's magnetic field lines stretch into a long, comet-shaped magnetotail, which extends thousands of miles away from the Earth. Bursty Bulk Flows (BBFs) are transient, high-speed ion bulk flows in the magnetotail that play an essential role in energy and mass transport. Characterized by their short-lived duration, they are related to magnetic reconnection events. This investigation focuses on being able to identify BBFs using the Magnetospheric Multiscale (MMS) probes, a mission consisting of four probes arranged in a tetrahedron to study the Earth’s magnetosphere. We examine parameters such as energy spectra, spin bulk velocity, …

Holographic Sensors For The Detection Of Volatile Organic Compounds, Graceson Antony

Doctoral

Volatile organic compound (VOC) monitoring at parts-per-million (ppm) concentration levels is essential for occupational safety, indoor air quality, and regulatory compliance. Although holographic gas sensors have been widely investigated, most operate in reflection mode as qualitative visual indicators, with limited quantitative evaluation of sensing mechanisms and scarce systematic demonstrations of repeatable multi-cycle validation for VOCs at ppm concentrations. A physics-based optimisation framework for transmission-mode holographic gas sensors which can bridge this gap has remained largely undeveloped.

This thesis presents the development and optimisation of real-time transmission-mode volume phase transmission holographic grating (VPTHG) sensors for ppm-level VOC detection. A comprehensive theoretical …

I Think, Therefore I Can: Self-Efficacy, Self-Regulation, And Sense Of Belonging In Introductory Physics, Danielle Christine Maldonado

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cognitive and affective beliefs in physics classrooms are important indicators of student success beyond traditional measurements of academic performance. This body of work explores major beliefs and processes, including self-efficacy, self-regulation, and sense of belonging, as they relate to academic achievement among introductory undergraduate physics students. First, this dissertation explores the development of physics self-efficacy and physics sense of belonging, two highly correlated variables. This work identifies unique sources of physics self-efficacy and sense of belonging development from current and prior academic experiences, personality factors, and demographic variables. Then, relationships between early- semester self-efficacy and sense of belonging, mid-semester …

Comparison Of Push-Pull Air Curtain To Overhead Downdraft Systems On Aerosol Containment And Distribution In Controlled Environments, Manal Mutairi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract

Comparison of Push-Pull Air Curtain to Overhead Downdraft Systems on Aerosol Containment and Distribution in Controlled Environments.

This dissertation looks at the ongoing issue of tiny airborne particles created during medical and dental procedures and evaluates ways to reduce the risk of exposure for healthcare workers and patients to these particles. The first study focuses on the size, how long particles stay in the air, and how far they travel from common medical procedures that create aerosols, showing that tiny particles (less than 5 µm) can stay in the air long enough to escape basic droplet controls. As a …

Evidence For A Spectral Break Or Curvature In The Spectrum Of Astrophysical Neutrinos From 5 Tev To 10 Pev, Karen Andeen

Physics Faculty Research and Publications

We report improved measurements of the all flavor astrophysical neutrino spectrum with IceCube by combining complementary neutrino samples in two independent analyses. Both analyses show evidence of a harder spectrum at energies below  ∼30  TeV compared to higher energies where the spectrum is well characterized by a power law. The spectrum is better described by a log parabola or a broken power law, the latter being the preferred model. Both, however, reject a single power law over an energy range 5 TeV–10 PeV with a significance  >4⁢𝜎, providing new constraints on properties of cosmic neutrino sources.

Harnessing Coherent-Wave Control For Sensing Applications In Scattering Media, Pablo Xavier Jara Palacios

Doctoral Dissertations

"Diffuse electromagnetic waves are widely used for non-invasive sensing and imaging in complex scattering media such as biological tissues. A fundamental limitation of such techniques is the scarcity of detected photons: as the source-detector separation increases to access deeper regions of the medium, the signal strength decays rapidly, leading to poor signal-to-noise ratio and limited sensitivity. This dissertation addresses this challenge through a combination of theory and computation.

We show that coherent control of the incident optical wavefront can compensate for the scarcity of detected photons that limits conventional diffuse optical imaging, typically performed in the near-infrared spectral region. By …

Explainable Physics-Based Constraints On Reinforcement Learning For Accelerator Optimization, Jonathan Colen, Malachi Schram, Kishansingh Rajput, Armen Kasparian

Data Science Faculty Publications

We present a reinforcement learning (RL) framework for optimizing particle accelerator experiments that builds explainable physics-based constraints on agent behavior. The goal is to increase transparency and trust by letting users verify that the agent’s decision-making process incorporates suitable physics. Our algorithm uses a learnable surrogate function for physical observables, such as energy, and uses them to fine-tune how actions are chosen. This surrogate can be represented by a neural network or by an interpretable sparse dictionary model. We test our algorithm on a range of particle accelerator optimization environments designed to emulate the Continuous Electron Beam Accelerator Facility at …

Spectral Phase Pulse Shaping Alters Photoionization Time, James Aygun, Dany Yaacoub, Allison L. Harris

Faculty publications – Physics

Photoionization is a key step in many attosecond processes. Accurately determining the photoionization time delay is critical to understanding electron dynamics during and after ionization and can guide future efforts to manipulate electron motion. Prior studies have shown that the photoionization time delay is non-zero and that pulse shaping through alteration of the spectral phase may change the number and timing of ionization events. In order to assess whether and how the spectral phase modifies the photoionization time delay, we use attosecond streaking simulations to extract the streaking time delay for ionizing pulses with identical power spectra, but different spectral …

Optimizing Microscale Tesla Valve Design For Enhanced Efficiency For Filtering And Sorting Bacteria, Brian Ewalt

2026 Research Poster Competition

Invented by Nikola Tesla in 1920, a Tesla valve is a passive check valve with no moving parts but showing diodicity for fluids (i.e., allowing fluids to flow easily in one direction but not in the other). Tesla valves have demonstrated remarkable versatility across a range of scientific fields. Recently, a study conducted at the University of Arkansas showed that these conduits exhibited diodicity for bacteria in the absence of fluid flows (Rogers et al. 2023), serving as proof of concept for applying microscale Tesla valves for filtering and sorting bacteria and microorganisms in biomedical settings. However, the design of …

An Application Of Molecular Dynamics To Hed Plasma Physics: Point And Group Defect Diffusion In Coulomb Crystals, Levi Webb

Theses and Dissertations

Molecular dynamics (MD) simulations are used to explore the microscopic behaviors of complex systems that cannot be easily studied experimentally. In particular, the microphysics of high energy density (HED) astrophysical plasma environments remain inaccessible by modern experiment---even in laser facilities, these plasmas exist only on short timescales that do not lend easily to investigation. The diffusion of point and group defects through crystallized plasmas in the cores of white dwarfs and neutron star crusts, called Coulomb crystals, has potentially macroscopic implications for the evolution of these bodies. Thus, I employ the widely-used MD code LAMMPS to simulate small Coulomb crystal …

Detection And Quantification Of Spreading Depolarization In Drosophila Melanogaster Using High-Throughput, Wide-Field Brain Imaging, Wolfgang Stein, Allison L. Harris

Faculty publications – Physics

Spreading depolarization (SD) is a ubiquitous neural phenomenon implicated in mammalian neurological disorders including cerebral ischemia, brain death, stroke, brain injury, and migraine, as well as in insect chill coma. During SD, a breakdown of ion homeostasis and a slowly spreading wave of neural depolarization leads to processing deficits, such as sensory disturbances and paralysis. Our protocols introduce high-throughput techniques using wide-field fluorescence brain imaging in Drosophila melanogaster larvae and adults to detect and quantify the spatial and temporal dynamics of SD and its initiation points. Two SD initiation techniques, rapid cooling and pharmacological manipulation, are detailed. The larval protocols …

A Nuclear Terrorism Scenario: Improvised Nuclear Weapons With 60%-Enriched Uranium, Matt Caplan

Faculty publications – Physics

In this work we show that approximately 60–70 kg of 60%-enriched uranium can be used to build a crude nuclear weapon with a kiloton yield. While too large to fit on a missile, such a weapon could be delivered by a shipping container. This analysis is motivated by the June 2025 Israeli and US attacks on Iran, especially the bombings of the nuclear facilities at Natanz, Fordow and Isfahan. The Iranian stockpile of approximately 440 kg of 60%-enriched uranium is, at the time of writing, inaccessible to IAEA inspectors and stored in secret. The rapid clandestine relocation of this material …