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Characterization Of An Ambe Tagged Neutron Source For A 30-Ton Wbls Detector, Rylee Grover 2026 Embry-Riddle Aeronautical University

Characterization Of An Ambe Tagged Neutron Source For A 30-Ton Wbls Detector, Rylee Grover

Discovery Day - Daytona Beach

Understanding the detection capabilities of water-based liquid scintillator (WbLS) is critical for its deployment in next-generation neutrino detectors such as THEIA and Phase II of the Deep Underground Neutrino Experiment (DUNE). This study focuses on the characterization and alignment testing of an Americium-Beryllium (AmBe) radioactive neutron source. We plan to dope the 30-ton WbLS detector at Brookhaven National Laboratory (BNL) with Gadolinium (Gd) to improve neutron detection capabilities. This will be tested by the implementation of an AmBe source as a calibration metric. The AmBe source emits neutrons coincident with a 4.4 MeV gamma ray, making it possible to perform …


Estimating The Effects Of Dark Matter Capture On The Sun Using Asteria And Analytic Stellar Scaling, Skylar G. Butler 2026 Embry-Riddle Aeronautical University

Estimating The Effects Of Dark Matter Capture On The Sun Using Asteria And Analytic Stellar Scaling, Skylar G. Butler

Discovery Day - Daytona Beach

We investigate how the internal structure of the Sun would change if dark matter particles were present at densities predicted by Galactic halo models. Dark matter capture rates were computed using the Python code Asteria, which implements the multi-element capture formalism of Gould (1987) to determine the rate at which dark matter particles scatter and become gravitationally bound inside the Sun. Because Asteria calculates only the capture rate, we developed a post-processing Python-based analysis to estimate the resulting physical effects using analytic scaling relations from previous solar dark matter studies. These relations were used to compute the effective dark matter …


Measuring Lyman Continuum Photon Luminosity In H Ii Regions, Brianna Johnshon 2026 Embry-Riddle Aeronautical University

Measuring Lyman Continuum Photon Luminosity In H Ii Regions, Brianna Johnshon

Discovery Day - Daytona Beach

This project focuses on measuring the Lyman continuum photon luminosity (Lc) of diffuse H II regions using multi-line observations from the Wisconsin H-Alpha Mapper (WHAM). Previous work by Sahan & Haffner (2016) analyzed the λ Ori region in Hα, [S II], and [N II], which I build on by refining assumptions about distance, extinction, and background emission, as well as extending the analysis to additional regions such as Perseus. To define the extent of each H II region, I identify the brightest Hα beam and select surrounding beams within 0.25σ of that peak. I then applied two different approaches to …


The Mystery Of Ngc2264-196'S Pulsation, Matthew Hernandez, Jadia Renee Ewing, Leila Alamos, Jacob R. Romeo, Kaelyn Weddle, Divyeshwari Vansadia, Thomas Matney, Marcus Flesher, Desiree Robinson, Alexandra Beianu 2026 Embry-Riddle Aeronautical University

The Mystery Of Ngc2264-196'S Pulsation, Matthew Hernandez, Jadia Renee Ewing, Leila Alamos, Jacob R. Romeo, Kaelyn Weddle, Divyeshwari Vansadia, Thomas Matney, Marcus Flesher, Desiree Robinson, Alexandra Beianu

Discovery Day - Daytona Beach

Matthew Hernandez, Jadia R. Ewing, Leila Alamos, Jacob Romeo, Kaelyn Weddle, Vansadia, TJ Matney, Maybelline A. Flesher, Desiree Robinson, Alexandra Beianu Faculty Mentor: Dr. Stephen D. Gillam Department of Physical Sciences Embry-Riddle Aeronautical University, Daytona Beach, FL USA.   March 2026 This study investigates the pulsation characteristics of NGC 2264-196, a chemically peculiar star within the young open cluster NGC 2264. Classification as a suspected Rapidly Oscillating Ap (roAp) star is supported by its spectral type (F5/7) and the recurring detection of a pulsation frequency near 3.01~ mHz. Photometric data was obtained over eight recorded oscillations: 121520UT, 111923UT, 070124UT, 080124UT, 012525UT, …


Quantifying The Effect Of Metallicity On Stellar Properties And Evolutionary Timescales, Jacob Becker 2026 Embry-Riddle Aeronautical University

Quantifying The Effect Of Metallicity On Stellar Properties And Evolutionary Timescales, Jacob Becker

Discovery Day - Daytona Beach

Stellar age estimations derived from asteroseismology depend on stellar models that are sensitive to metallicity (Z). Variations in this parameter could alter the agreement between gyrochronological and asteroseismic ages, as well as main sequence lifetimes and observational properties such as effective temperature and luminosity. We test how much typical metallicity differences (±0.2 dex) affect main-sequence models of solar-type stars. Using MESA, evolutionary tracks are created for 1 M☉ stars at three metallicities (Z = 0.009, 0.014, 0.022), and it is measured how these changes shift the positions of the zero-age main sequence and the corresponding main sequence lifetimes. This work …


Broad Emission-Line Limits On Stellar Winds From Small-Aperture Dslr Spectroscopy, Benjamin Katz, David Cardona 2026 Embry-Riddle Aeronautical University

Broad Emission-Line Limits On Stellar Winds From Small-Aperture Dslr Spectroscopy, Benjamin Katz, David Cardona

Discovery Day - Daytona Beach

Broad Emission-Line Limits on Stellar Winds from Small-Aperture DSLR Spectroscopy   Wolf-Rayet (WR) stars have very strong stellar winds, with speeds of thousands of km/s, usually measured using high-resolution spectroscopy on large telescopes. Here, we test how well those speeds can be recovered using small-aperture, low-resolution DSLR spectroscopy. We used an 8-inch Celestron 8SE with an SA-100 grating and a Nikon D750 DSLR, giving a dispersion of about 4.1 Å per pixel. A key limitation is the instrumental resolution of the system, with an FWHM of about 30 Å, which is not small compared to the emission line widths being measured. …


Precise Stellar Age Constraints And Habitable Zone Evolution In Exoplanet Systems, Grace Henry 2026 Embry-Riddle Aeronautical University

Precise Stellar Age Constraints And Habitable Zone Evolution In Exoplanet Systems, Grace Henry

Discovery Day - Daytona Beach

Accurate stellar ages are fundamental to interpreting the evolutionary histories of habitable zone (HZ) planets. Because stellar luminosity evolves over time, HZ boundaries migrate outward, meaning that present-day HZ planets may have experienced very different irradiation environments earlier in their evolution. Accurate ages are therefore required to estimate HZ residence times and place planetary habitability in an evolutionary context. We use the Bayesian Analysis of Stellar Evolution with nine parameters (BASE-9) code to constrain ages and masses for exoplanet host stars with planets located in the HZ. Our sample includes single stars with effective temperatures of 4475–7200 K that host …


Tess Study Of Wolf-Rayet Stars In The Large Magellanic Cloud, Benjamin Katz, Kassidy Myers, Bailey Wolf, Anthony Fabrega, William Punches 2026 Embry-Riddle Aeronautical University

Tess Study Of Wolf-Rayet Stars In The Large Magellanic Cloud, Benjamin Katz, Kassidy Myers, Bailey Wolf, Anthony Fabrega, William Punches

Discovery Day - Daytona Beach

TESS Study of Wolf-Rayet Stars in the Large Magellanic Cloud   Wolf-Rayet (WR) stars are massive and rare stars whose evolution is mainly changed by stellar winds or binary interactions. In a lot of cases, WR stars are found in binary systems with a companion star, often an O-type star, which can help astronomers find the mass and other properties of the WR star. The Large Magellanic Cloud (LMC), located about 50 kpc from the Milky Way, has a lower metallicity than the Milky Way which makes it a useful place to study Wolf-Rayet stars. For this project, we will study …


Unveiling Stellar Core Depletion In Ngc 4649 With Jwst Nircam, Sydney Krause 2026 Embry-Riddle Aeronautical University

Unveiling Stellar Core Depletion In Ngc 4649 With Jwst Nircam, Sydney Krause

Discovery Day - Daytona Beach

Galaxies are considered to have depleted cores when the central region’s concentration of stars is lower than typical, a feature linked to supermassive black hole formation and vital in galaxy evolution studies. In this project, “Unveiling Stellar Core Depletion in NGC 4649 with JWST NIRCam”, Space-based archival data from the James Webb Space Telescope (JWST) Near Infrared Camera (NIRCam) was utilized for several forms of analysis. Initial analysis involved accessing these images via SAO DS9, an astrophysics software for viewing and manipulating files. These images were analyzed using Photoutils, a Python based coding package, part of the Astropy extension. To …


Modeling Doppler-Shifted Solar Spectra From Simulated Asteroidal Dust Populations Using Orbital Evolution Codes, Skylar G. Butler, Jarrett Dieterle 2026 Embry-Riddle Aeronautical University

Modeling Doppler-Shifted Solar Spectra From Simulated Asteroidal Dust Populations Using Orbital Evolution Codes, Skylar G. Butler, Jarrett Dieterle

Discovery Day - Daytona Beach

We investigate how orbital properties of interplanetary dust particles produce Doppler-shifted solar absorption lines using synthetic spectra generated from particle outputs of a numerical orbital evolution code. The code is based on the Ipatov dynamical model, written in Fortran and using the SWIFT integration package to track the evolution of dust particles originating from asteroid and comet populations. The program reads input files containing particle orbital elements and heliocentric positions, along with planetary parameters and integration settings, and computes the time evolution of particle trajectories under gravitational perturbations. The resulting particle states are then used to generate synthetic spectra by …


Ngc 4374 With Jwst/Nircam: A Central Structural Analysis Revealing A Depleted Core And Agn, Elizabeth Crevinston 2026 Embry-Riddle Aeronautical University

Ngc 4374 With Jwst/Nircam: A Central Structural Analysis Revealing A Depleted Core And Agn, Elizabeth Crevinston

Discovery Day - Daytona Beach

We use James Webb Space Telescope’s (JWST) Near Infrared Camera (NIRCam) F150W imaging to study the central regions of massive elliptical galaxies, focusing on their partially depleted cores. These cores are thought to form when a binary supermassive black hole (SMBH) ejects stars from the central regions through dynamical three-body interactions. After the binary coalesces, gas accretion onto the newly formed SMBH can trigger a compact active galactic nucleus (AGN), which plays a key role in regulating star formation and shaping galaxy structure. With JWST NIRCam, we extracted the surface brightness profile of NGC 4374, a giant elliptical galaxy in …


Measuring Cosmic Expansion From Early To Late Times Using Quasars, Galaxies, & Local Supernovae, Rajeev Vaisakh 2026 Southern Methodist University

Measuring Cosmic Expansion From Early To Late Times Using Quasars, Galaxies, & Local Supernovae, Rajeev Vaisakh

Physics Theses and Dissertations

This dissertation investigates the evolution of cosmic expansion across a wide redshift ($z$) range by combining measurements from quasars \& galaxies in the distant universe $(z > 0.8)$ with those obtained from stripped-core collapse supernovae observations from the nearby universe $(z < 0.1)$. Using the DESI spectroscopic survey, we analyze large-scale clustering from quasars over $0.8 < z < 2.1$ and emission line galaxies over $0.8 < z < 1.6$, contributing to DESI DR2 BAO and full-shape measurements of cosmic expansion and structure growth. Combined with BBN in flat $\Lambda$CDM, DESI DR2 BAO gives $H_0 = 68.51 \pm 0.58$ km s$^{-1}$ Mpc$^{-1}$, while combinations of DESI BAO with CMB and supernova data show a preference for evolving dark energy, with representative constraints such as $w_0 = -0.752 \pm 0.057$ and $w_a = -0.86^{+0.23}_{-0.20}$ for DESI+CMB+DESY5. Using the ROTSE-III Supernova Survey and the expanding photosphere method (EPM), we measure distances to a sample of six supernovae for which the thermal phase can be clearly identified. This analysis focuses on testing whether reliable EPM distances can be obtained for this population. The resulting distances will eventually be compared with independent estimates from the literature. Establishing consistency with these external measurements represents an important step toward applying this methodology to larger samples, with the eventual goal of using ROTSE supernova distances to provide an independent measurement of the local Hubble constant.


Out Of This World: An Exoplanetary Workshop, Monica Storss, Bart Kuipers 2026 Northeastern University

Out Of This World: An Exoplanetary Workshop, Monica Storss, Bart Kuipers

ELO (un)supervised 2026

The workshop investigates how scientific constraints can productively defamiliarize human experience and create new frameworks for creativity and expression. Participants will produce original work while considering broader questions about environment, perception, and cultural formation in speculative contexts, and how the arts, sciences, and technology inform each other in relational multiplicities. This generative workshop explores how astronomical data from confirmed exoplanets can generate new poetic forms and linguistic constraints. Participants will examine how exoplanetary conditions can shape language, metaphor, and narrative structure. We'll develop from writing exercises that respond to non-terrestrial physical parameters: alternative light spectra, gravitational variations, and atmospheric compositions. …


Detection Of C60 Combination Bands In The Near-Ir Spectrum Of Tc 1, Morgan M. Giese, Vincent J. Esposito, Simon Van Schuylenbergh, Jan Cami, Els Peeters, Charmi Bhatt, Dries Van De Putte, A. G. G. M. Tielens, Michael J. Barlow, Jeronimo Bernard-Salas, Alessandra Candian, Bryan Changala, Nick L. J. Cox, Harriet L. Dinerstein, D. A. García-Hernández, Marco A. Gómez-Muñoz, Kay Justtanont, Kathleen E. Kraemer, Eric Lagadec, Arturo Manchado, Ana Monreal Ibero, Raghvendra Sahai, Ameek Sidhu, G. C. Sloan, N. C. Sterling, Jeremy R. Walsh, Roger Wesson, Joshua Cole Whitman, Albert Zijlstra 2026 The University of Western Ontario

Detection Of C60 Combination Bands In The Near-Ir Spectrum Of Tc 1, Morgan M. Giese, Vincent J. Esposito, Simon Van Schuylenbergh, Jan Cami, Els Peeters, Charmi Bhatt, Dries Van De Putte, A. G. G. M. Tielens, Michael J. Barlow, Jeronimo Bernard-Salas, Alessandra Candian, Bryan Changala, Nick L. J. Cox, Harriet L. Dinerstein, D. A. García-Hernández, Marco A. Gómez-Muñoz, Kay Justtanont, Kathleen E. Kraemer, Eric Lagadec, Arturo Manchado, Ana Monreal Ibero, Raghvendra Sahai, Ameek Sidhu, G. C. Sloan, N. C. Sterling, Jeremy R. Walsh, Roger Wesson, Joshua Cole Whitman, Albert Zijlstra

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We report the detection of a set of new near-infrared emission features between 3.5 and 5.2 μm in JWST/NIRSpec observations of Tc 1, the planetary nebula known for displaying the cleanest and most prominent mid-infrared cosmic fullerene spectrum. These broad features share the same spatial distribution as the well-known C60 and C70 mid-infrared emission bands, peaking in an asymmetric ring approximately 5″–6″ from the central star. Through comparison with new anharmonic quantum chemical calculations, we demonstrate that these features arise from C60 combination bands, marking their first detection in an astrophysical environment. The total energy radiated …


1d Crust-Magnetosphere Coupling Model For Magnetars, Kennedy M. Jeter 2026 CUNY Graduate Center

1d Crust-Magnetosphere Coupling Model For Magnetars, Kennedy M. Jeter

Dissertations, Theses, and Capstone Projects

Magnetars are the most extremely magnetized objects in the universe. Their strong magnetic fields generate high-energy magnetic flares with instantaneous luminosity that can outshine their host galaxy. Previous works have explored how Hall drift in the crust affects the dynamics of magnetic field lines in the magnetosphere. This work investigates how a change in the magnetosphere, such as a flare or an outburst, can excite Hall evolution in the crust. We investigate how the twisting and untwisting of magnetic field lines in a magnetar’s magnetosphere launches Hall waves through its crust using a one-dimensional numerical model. We use the Dedalus …


Modeling Turbulent Accretion Flows Around Black Holes: Azimuthal Flux Derivative Density Curves In 3d Mhd Simulations, Sasmitha Purushothaman, Matthew D. Duez, Pavan Chawhan 2026 Portland State University

Modeling Turbulent Accretion Flows Around Black Holes: Azimuthal Flux Derivative Density Curves In 3d Mhd Simulations, Sasmitha Purushothaman, Matthew D. Duez, Pavan Chawhan

University Honors Theses

When modeling two-dimensional axisymmetric accretion disks around Kerr black holes, setting the azimuthal terms of the MHD equations to zero causes the loss of turbulence and dynamo effects. In this paper, we use three-dimensional models to identify the turbulence that arises from azimuthal flux derivatives (AFDs) and create probability density functions to characterize them. We establish a pipeline for calculating the AFDs, creating a distribution, and normalizing it. Then, we plot the dependence of the conditional probability of the AFDs on density, magnetic field strength, and velocity for the continuity and magnetic induction equations. Future research can take this information …


Search For Slow-Moving Magnetic Monopoles With An Improved High-Energy Event Removal Algorithm, Reeshi N. Gihosal 2026 University of South Alabama

Search For Slow-Moving Magnetic Monopoles With An Improved High-Energy Event Removal Algorithm, Reeshi N. Gihosal

Honors Theses

Fermilab’s NOvA (NuMI Off-axis 𝑣𝑒 Appearance) experiment focuses on understanding the behavior of neutrinos and how they affect the cosmos. A sub-focus of the NOvA experiment is the search for magnetic monopoles. These elusive particles have not yet been observed in nature, leaving their behavior to be mysterious. The Far Detector, located in Ash River, MN, is integral in the search for these particles. This project is on simulated magnetic monopoles with speeds thousandths the speed of light, with focus on the role of slicing algorithms in event reconstruction using the NOvA experiment’s reconstruction algorithm. Using sample data, analysis occurred …


Intermediate-Scale Outflow Dynamics Of Eta Carinae, Edmund J. Garcia, Matthew C. Fleenor 2026 University of Mary Washington

Intermediate-Scale Outflow Dynamics Of Eta Carinae, Edmund J. Garcia, Matthew C. Fleenor

Departmental Honors & Graduate Capstone Projects

η Carinae (η Car) is a binary system, with the larger star being an extremely massive, luminous blue variable (LBV) beyond the Eddington Limit. Surrounding the η Car system, numerous multi-wavelength imaging campaigns reveal axisymmetric structures with the expanding bipolar Homunculus Nebula (¡1 pc). In combination with the episodic eruptive history of the η Car system, our initial intermediate-scale imaging revealed further axisym- metric structures (1-5 pc). To gain a more expansive view of how the small scale structure connects to panoramic imaging of the η Car region, we constructed a deep, optical, narrowband mosaic of 189 images utilizing the …


Information Theory Analysis Of The Solar Wind Magnetic Structures For Space Weather Prediction, Katherine Holland 2026 Embry-Riddle Aeronautical University

Information Theory Analysis Of The Solar Wind Magnetic Structures For Space Weather Prediction, Katherine Holland

Doctoral Dissertations and Master's Theses

Forecasting space weather at Earth is highly complicated, because of the limited measurements of the dynamic processes in the Sun that span multiple temporal, spatial, and energy-scales. The solar wind is a highly structured, multi-scale, evolving plasma and consists of coronal mass ejections (CMEs), stream interaction regions (SIRs), expanding flux tubes (Borovsky, 2008), and interplanetary magnetic field (IMF) discontinuities and fluctuations. The aim of this research is to improve our understanding of the evolution and dissipation of different scale-size solar wind magnetic structures as they move from the Sun-Earth Lagrange point 1 (L1) to Earth's bow shock and, ultimately, to …


Searching For Temporal Variations In The Fine-Structure Constant Using Espresso Spectrograph Data, David Hoffman IV 2026 University of South Carolina - Columbia

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

Senior Theses

The fine-structure constant α is a dimensionless constant, defined as e²/(4πε₀ℏc) ≈ 1/137. On the order of human timescales, its value is very much unchanging, however, in recent years there has been extensive debate over whether or not the value of α has remained constant over cosmological timescales. With the natural corollary to a changing α being that either one or multiple of its constituent physical constants have also changed in value, observing a variation in the fine-structure constant would have vast ramifications for our understanding of the nature of the early universe and how it has evolved. While past …


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