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Full-Text Articles in Stars, Interstellar Medium and the Galaxy

Estimating The Effects Of Dark Matter Capture On The Sun Using Asteria And Analytic Stellar Scaling, Skylar G. Butler Aug 2026

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 Aug 2026

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 Aug 2026

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 Aug 2026

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 Aug 2026

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 Aug 2026

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 Aug 2026

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 …


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

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. …


1d Crust-Magnetosphere Coupling Model For Magnetars, Kennedy M. Jeter Jun 2026

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 …


Intermediate-Scale Outflow Dynamics Of Eta Carinae, Edmund J. Garcia, Matthew C. Fleenor Apr 2026

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 …


Constraining The Impact Threat From Small Bodies In Near Earth And Cislunar Space, Skylar G. Butler, Jarrett Dieterle, Henry Sanders, Aiden Kelleher Feb 2026

Constraining The Impact Threat From Small Bodies In Near Earth And Cislunar Space, Skylar G. Butler, Jarrett Dieterle, Henry Sanders, Aiden Kelleher

Student Research Symposium (SRS)

Understanding and mitigating the impact threat posed by small bodies in near-Earth and cislunar space is vital for planetary defense, spacecraft safety, and sustainable space operations. This research integrates dynamical evolution modeling, synthetic observations, and reprocessed infrared data to assess the origins and potential hazards of debris from young asteroid families. By modeling the trajectories and orbital evolution of fragments from the Datura, Emilkowalski, 1992 YC2, Lucascavin (Nesvorný & Vokrouhlický, 2006), and Veritas (Nesvorný et al., 2003) families, we constrain how these sources contribute to near-Earth debris populations. Reprocessing Infrared Astronomical Satellite (IRAS) data with Fourier-filtering techniques reveals fine-structure variations …


Solar Wind–Magnetosphere Coupling During The September 2025 Cme: Multi-Spacecraft Analysis Using Mms And Omni Data, Skylar G. Butler, Margret Stanley Feb 2026

Solar Wind–Magnetosphere Coupling During The September 2025 Cme: Multi-Spacecraft Analysis Using Mms And Omni Data, Skylar G. Butler, Margret Stanley

Student Research Symposium (SRS)

A sequence of two coronal mass ejections (CMEs) impacted Earth in early September 2025, producing consecutive geomagnetic disturbances. The first CME, launched on 31 August 2025 and observed as a halo in SOHO/LASCO imagery, reached Earth on 1 September (~20:45 UTC), generating a clear interplanetary shock. OMNI 1-min solar-wind data show a sudden rise in |B| from ≈ 5 nT to > 25 nT, proton density and velocity increases (≈ 350 → 600 km s⁻¹), and a southward IMF Bz interval that drove enhanced coupling. The Kyoto Dst index recorded a sudden storm commencement followed by a minimum of −75 nT …


How Hidden Companions Skew Stellar Ages: A Binary-Inclusive Analysis Of Ngc 2168, Skylar G. Butler Feb 2026

How Hidden Companions Skew Stellar Ages: A Binary-Inclusive Analysis Of Ngc 2168, Skylar G. Butler

Student Research Symposium (SRS)

We expand upon our previous analysis of NGC 2168 (M35), which investigated the precision of isochrone-based age determination for individual main-sequence stars using photometric modeling. Building on that earlier framework, we now assess how inferred stellar ages change when each object is modeled under the assumption that it may possess an unresolved binary companion. Using post burn in posterior samples from the same dataset, we computed the mean Stage 3 ages for more than 3,000 cluster members with binaries turned on, allowing a direct comparison to our prior results with binaries turned off. The resulting age distribution peaks near 2.1 …


Modeling The Secondary Catastrophic Disruption Of The Veritas Family, Jarrett Dieterle, Skylar G. Butler, Aiden Kelleher Feb 2026

Modeling The Secondary Catastrophic Disruption Of The Veritas Family, Jarrett Dieterle, Skylar G. Butler, Aiden Kelleher

Student Research Symposium (SRS)

The Veritas asteroid family, located in the outer main belt, is believed to have formed from the catastrophic breakup of a parent body approximately 8.3 million years ago (e.g., Nesvorný et al., 2003). Larger fragments remained in the main belt, while smaller particles evolved inward under radiation forces, forming a toroidal dust structure observable in infrared data as paired bands. Previous studies (e.g., Dermott et al., 2001) have shown that these bands can be linked to their parent families and modeled from their initial disruptions. We propose that the 10° dust bands associated with Veritas may record evidence of a …


Numerical Modeling Of Multi-Scale Jet Feedback In Seyfert Galaxies, Julianne Goddard Jan 2026

Numerical Modeling Of Multi-Scale Jet Feedback In Seyfert Galaxies, Julianne Goddard

Theses and Dissertations--Physics and Astronomy

We present a suite of high-resolution cosmological zoom-in simulations investigating the impact of mechanical and thermal feedback from low-luminosity jets launched from supermassive black holes (SMBHs) on Seyfert galaxy evolution from early cosmic times to the present (z ≤ 10). Our models follow the formation of central galaxies within identical dark matter halos of logMhalo/M⊙ ∼ 11.8 at z = 0, seeded with ∼ 10^6M⊙ SMBHs at z ∼ 9.1 and z ∼ 3.7. Feedback from active galactic nuclei (AGN) is implemented in the form of bipolar jets launched along the SMBH spin axis, with jet powers spanning Ljet ∼ …


Determining The 17f(Α,P)20ne Reaction Rate For Application In Type I X-Ray Bursts, William Braverman Nov 2025

Determining The 17f(Α,P)20ne Reaction Rate For Application In Type I X-Ray Bursts, William Braverman

LSU Doctoral Dissertations

The 17F(α, p)20Ne reaction has been identified as an alternate pathway for breakout from the hot-CNO cycle that can be important in some X-ray burst scenarios. The 17F(α, p)20Ne reaction rate was previously determined through a parameterized exponential S-factor with a large enhancement from thermally-excited states based on statistical models with large uncertainties. We have measured the time-inverse 20Ne(p,α)17F cross section at center-of-mass energies ranging from 5.50 to 7.10 MeV using an activation method with a proton beam on a neon gas cell. Coincident detections of 511-keV γ-rays, resulting from electron-positron …


Determining The Light Curve And 3d Shape Of Asteroid Eunomia And Egeria Using Relative Photometry, Skylar G. Butler, Jackson Ladd Sackrider Sep 2025

Determining The Light Curve And 3d Shape Of Asteroid Eunomia And Egeria Using Relative Photometry, Skylar G. Butler, Jackson Ladd Sackrider

Discovery Day - Daytona Beach

Asteroids are relics of our solar system’s early formation, preserving valuable information about planetary evolution. Understanding their rotational properties and surface features provides deeper insights into the dynamical and thermophysical processes that shape their evolution. This study aims to conduct photometric observations of two main-belt asteroids, Egeria and Eunomia, using the Embry-Riddle Aeronautical University 1-meter telescope. Observations will be conducted in the red band on February 28 and March 14, 2025, over five-hour sessions, capturing full rotational light curves for each asteroid. These data will be analyzed using MPO Canopus to generate 3D surface models through photometric inversion techniques. The …


Satellite-Host Galaxy Co-Evolution With Next-Generation Regulator Models, Austen Gabrielpillai Sep 2025

Satellite-Host Galaxy Co-Evolution With Next-Generation Regulator Models, Austen Gabrielpillai

Dissertations, Theses, and Capstone Projects

The evolution of satellites galaxies is an unsolved problem in galaxy formation. Recent observations such as the SAGA and ELVES surveys find tension in HI contents and star formation of satellites around their central host galaxies when compared to our own local environment, the Milky Way. These processes are potentially highly influenced by the host's circumgalactic medium (CGM), and to constrain these cases requires accurate and fast modeling of satellites-host interactions. In this work, we present our methodology for evolving z = 0 surviving satellites alongside their central galaxy in sapphire, a CGM regulator co-evolution model of galaxy formation. …


Orbital Evolution Of The Datura Asteroid Family, Skylar G. Butler Aug 2025

Orbital Evolution Of The Datura Asteroid Family, Skylar G. Butler

Beyond: Undergraduate Research Journal

To research the Datura Family of asteroids, we used an orbital evolution code to track the orbital decay of asteroid fragments released in an asteroid disruption. Different particle sizes of 10, 100, 500, 750, and 100 micrometers were tracked including the semi-major axis, eccentricity, and inclination in order to observe how certain particle sizes’ orbital elements evolve. Using a young asteroid family like the Datura family gives more insight into the parent asteroid structure and formation because the time is closer to before the asteroid’s breakup. We use these models to constrain the parameters of the dust by comparing the …


Chemical & Electromagnetic Signatures Of Binary Neutron Star Mergers, Benjamin Amend Aug 2025

Chemical & Electromagnetic Signatures Of Binary Neutron Star Mergers, Benjamin Amend

All Dissertations

Binary neutron star (BNS) mergers are some of the most energetic events in the universe, producing both short gamma-ray bursts (GRBs) and kilonovae. GRBs are brief, bright flashes of gamma rays, powered by ultra-relativistic jets launched during the merger. These jets produce a prompt burst of gamma rays, followed by a broadband afterglow generated by external shocks as the outflow interacts with the surrounding medium. Kilonovae are optical-infrared transients from the radioactive decay of heavy, neutron-rich nuclei formed through the rapid neutron capture process (r-process) in the merger ejecta. Together, GRBs and kilonovae provide unique laboratories for probing fundamental physics …


Response Of Galactic Disks To Dark Matter Halo Triaxiality, Alex J. Hutton Jan 2025

Response Of Galactic Disks To Dark Matter Halo Triaxiality, Alex J. Hutton

College of Graduate Studies: Theses & Dissertations

In this study we examine the influence of dark matter halo triaxiality on the evolution of galactic disks. We do this by running a series of collisionless N-body models. In a first set of models we place the galactic disk within an oblate halo at various orientations and examine the resulting evolution. In our second set we construct fully self-consistent models of a stellar disk embedded within a spherical halo, with an impacting external dark matter dwarf galaxy. After evolving the simulations for a Hubble time, we examine the disk orientation and warping along with other quantities such as bar …


From Stars To Moons: Investigating Stellar Rotations, Planetary Interactions, And Exoplanetary Prospects, Rosario Cecilio-Flores-Elie Sep 2024

From Stars To Moons: Investigating Stellar Rotations, Planetary Interactions, And Exoplanetary Prospects, Rosario Cecilio-Flores-Elie

Dissertations, Theses, and Capstone Projects

The thesis is divided into two key sections. The first chapter presents the results of analyzing TESS light curves for 99 targets within the Carina-Near moving group. By deriving rotational periods, this analysis supports stellar age estimation, contributing to the broader efforts of the Backyard Worlds: Planet 9 citizen project in determining age parameters for 89 newly identified systems, including ultracool dwarf companions. These findings enhance our understanding of stellar rotation and evolution, offering new insights into the development of secondary co-moving objects like brown dwarfs.

The second chapter investigates planet-moon interactions within our solar system by examining mass ratios, …


Density And Magnetic Field Asymmetric Kelvin‐Helmholtz Instability, Xuanye Ma, Peter Delamere, Katariina Nykyri, Antonius Otto, Stefan Eriksson, Lihui Chai, Brandon Burkholder, Andrew Dimmock, Yu-Lun Liou, Shiva Kavosi Mar 2024

Density And Magnetic Field Asymmetric Kelvin‐Helmholtz Instability, Xuanye Ma, Peter Delamere, Katariina Nykyri, Antonius Otto, Stefan Eriksson, Lihui Chai, Brandon Burkholder, Andrew Dimmock, Yu-Lun Liou, Shiva Kavosi

Publications

The Kelvin‐Helmholtz (KH) instability can transport mass, momentum, magnetic flux, and energy between the magnetosheath and magnetosphere, which plays an important role in the solar‐wind‐ magnetosphere coupling process for different planets. Meanwhile, strong density and magnetic field asymmetry are often present between the magnetosheath (MSH) and magnetosphere (MSP), which could affect the transport processes driven by the KH instability. Our magnetohydrodynamics simulation shows that the KH growth rate is insensitive to the density ratio between the MSP and the MSH in the compressible regime, which is different than the prediction from linear incompressible theory. When the interplanetary magnetic field (IMF) …


The Computational Search For Unidentified Central Configurations Of The Newtonian N-Body Problem, Hannah G. Havel Jan 2024

The Computational Search For Unidentified Central Configurations Of The Newtonian N-Body Problem, Hannah G. Havel

CURE Proceedings

The N-body problem is a field of study in mathematics and physics that involves predicting the motion of particles moving under their mutual gravitational attraction. It is vital in celestial mechanics, such as planning collision-free satellite orbit trajectories. When beginning to understand the N-body problem, we can start by looking at equal masses of these particles or celestial bodies. As particles move, their position and velocity change, both energy and angular momentum are conserved. Sets of constant energy and angular momentum, known as integral manifolds, are higher-dimensional figures that represent constraints of movement to a system. Integral manifolds are described …


Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part Ii: Experiment Description, Victor Christianto, T. Daniel Chandra, Florentin Smarandache Dec 2023

Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part Ii: Experiment Description, Victor Christianto, T. Daniel Chandra, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The present article was partly inspired by G. Pollack’s book, and also Dadoloff, Saxena & Jensen (2010). As a senior physicist colleague and our friend, Robert N. Boyd, wrote in a journal (JCFA, Vol. 1, No. 2, 2022), for example, things and Beings can travel between Universes, intentionally or unintentionally [4]. In this short remark, we revisit and offer short remark to Neil Boyd’s ideas and trying to connect them with geometry of musical chords as presented by D. Tymoczko and others, then to Escherian staircase and then to Jacob’s ladder which seems to pointto possibility to interpret Jacob’s vision …


Cosmic Diffuse Neutrino And Gamma-Ray Backgrounds In The Mev Regime, Ilukpitiye Samalka Anandagoda Aug 2023

Cosmic Diffuse Neutrino And Gamma-Ray Backgrounds In The Mev Regime, Ilukpitiye Samalka Anandagoda

All Dissertations

Cosmic Multi-Messenger backgrounds include relic diffuse components created in the early Universe and contributions from individual sources. In this dissertation, I present the work done in Anandagoda (2019); Anandagoda et al. (2020, 2023) where type Ia (SNe Ia) and core-collapse supernovae (CCSNe) contributions to the diffuse neutrino and gamma-ray backgrounds in the MeV regime are studied. These backgrounds are referred to as DSNB and DSGB respectively. Based on this work, the diffuse SN Ia background is ~106 times lower (for electron antineutrinos) than the CCSN background making it negligible. The predicted DSNB electron antineutrino flux at earth in the …


Floating Liquid Droplets On The Surface Of Cryogenic Liquids: Implications For Titan Rain, Kendra Farnsworth, Alejandro Soto, Vincent F. Chevrier, Jordan K. Steckloff, Jason M. Soderblom Feb 2023

Floating Liquid Droplets On The Surface Of Cryogenic Liquids: Implications For Titan Rain, Kendra Farnsworth, Alejandro Soto, Vincent F. Chevrier, Jordan K. Steckloff, Jason M. Soderblom

Space and Planetary Science Faculty Publications and Presentations

Saturn’s moon, Titan, has a hydrocarbon-based hydrologic cycle with methane and ethane rainfall. Because of Titan’s low gravity, “floating liquid droplets” (coherent droplets of liquid hydrocarbons that float upon a liquid surface) may form on the surface of Titan’s hydrocarbon lakes and seas during rainfall. Floating liquid droplets, however, have not been investigated in the laboratory under conditions appropriate for the surface of Titan (cryogenic, hydrocarbon, liquids). We conducted a set of experiments to simulate methane and ethane rainfall under Titan surface conditions (89–94 K, 1.5 bar nitrogen atmosphere) and find that floating ethane droplets form in a wide range …


The Final Step In Contact Binary Star Formation, Larry A. Molnar, Levi Carr, Henry Phippen Jan 2023

The Final Step In Contact Binary Star Formation, Larry A. Molnar, Levi Carr, Henry Phippen

Summer Research

A binary star is a system that contains two stars orbiting each other. A contact binary is a binary star whose component stars are so close that they share the same atmosphere (see Figure 1). They are the most common kind of eclipsing binary stars. Critical questions we have answered are: how do they form, how do they survive for a long time, and how do they ultimately die?


Astr 1: General Astronomy, David Goldberg Jan 2023

Astr 1: General Astronomy, David Goldberg

Open Educational Resources

No abstract provided.


The Radial Quenching Progression Of Nearby Galaxies, Chenyu Zhao Jan 2023

The Radial Quenching Progression Of Nearby Galaxies, Chenyu Zhao

Theses and Dissertations--Physics and Astronomy

In this dissertation, we explore the spatial distribution of quiescent regions within galaxies using data from the Sloan Digital Sky Survey IV Mapping Nearby Galaxies at Apache Point Observatory (SDSS-IV MaNGA). Our analysis focuses on a radial range spanning from 0.3 R e to 1.2 R e and involves the development of innovative data selection and processing methods. Through this investigation, we identify two prominent types of transition galaxies: central-star-forming galaxies (C-SF galaxies) and central-quiescent galaxies (C-Q galaxies). Notably, we observe a correlation between galaxy mass and the predominant type of transition, with more massive galaxies tending to be C-Q …