Astrophysics and Astronomy Commons^™

Theoretical Spectroscopic Predictions Of Electronically Excited States, Noah R. Garrett

Honors Theses

The quest for faster computation of anharmonic vibrational frequencies of both ground and excited electronic states has led to combining coupled cluster theory harmonic force constants with density functional theory (DFT) cubic and quartic force constants for defining a quartic force field (QFF) utilized in conjunction with vibrational perturbation theory at second order (VPT2). This work shows that explicitly correlated coupled cluster theory at the singles, doubles, and perturbative triples level [CCSD(T)-F12] provides accurate anharmonic vibrational frequencies and rotational constants when conjoined with any of B3LYP, CAM-B3LYP, BHandHLYP, PBE0, and ωB97XD for roughly one-quarter of the computational time of the …

Examining Galaxy Bulge Regions With The Sloan Digital Sky Survey, Sarah E. Draves, Ariyeh Maller

Publications and Research

Nearly all of the ordinary matter in the universe is located in galaxies, which are made up stars, gas, dust, and black holes, and range in size from a few thousand to a few hundred thousand light years across. Galaxies come in different shapes, but many of them are spiral shaped, and some of those have a central bulge region that is distinct from the rest of the galactic disk. This project used a large data set of galaxies that had their bulge and disk components separated to see what correlations those fractions of each galaxy have with other galaxy …

Cn Stretches Around 4.4 Microns Dominate The Ir Absorption Spectra Of Cyanopolycyclic Aromatic Hydrocarbons, Vincent J. Esposito, Ryan C. Fortenberry, Christiaan Boersma, Alexandros Maragkoudakis, Louis J. Allamandola

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Anharmonic quantum chemical computations reveal a strong, narrow (width = 0.075 μm) band in the 4.3–4.5 μm region of the absorption spectra of the cyano-substituted polycyclic aromatic hydrocarbons (CN-PAHs) cyanonaphthalene, cyanoanthracene, c yanophenanthrene, and c yanopyrene. This narro w windo w with intense IR lines implies that CN-PAHs of various shapes and sizes offer little variation in both wavelength and intensity in this region. Subsequently, this band can be used as a tracer for CN-PAHs. The distinct features making up the band are assigned to mixed vibrational states consisting of the CN stretch fundamental and various combination bands, including in-plane …

Analysis Of Bayesian Transfer Function Fitting Method - A Potential Tool For Estimating Interferometer Uncertainty, Caden Swain

Honors Thesis

The Response Function of the LIGO Interferometer is central to reconstructing the strain produced by incoming gravitational waves. As a function of the interferometer's response to external stimuli, the Response Function is both analytically modeled and experimentally measured using excitations from the photon calibrator system at discrete frequencies. The uncertainty in each data point is propagated to the residual between the model and measurements, with both the uncertainty and residual being interpolated over a broadband frequency range. This project explores an alternative method to estimating the uncertainty and systematic error present in the Response function model through the utilization of …

Energy Dependence Of Quasi-Periodic Oscillations In Accreting X-Ray Pulsars, Hemanth Manikantan, Biswajit Paul, Rahul Sharma, Pragati Pradhan, Vikram Rana

Publications

We present the results from an investigation of the energy dependence of quasi-periodic oscillations (QPOs) exhibited by accreting X-ray pulsars using data from archival XMM-Newton, NuSTAR, RXTE, and NICER observations. In a search for the presence of QPOs in 99 XMM-Newton and NuSTAR observations, we detected QPOs in eleven observations of five sources, viz., 4U 1626–67 (48 mHz), IGR J19294+1816 (30 mHz), V 0332+53 (2, 18, and 40 mHz), Cen X–3 (30 mHz), and XTE J1858+034 (180 mHz). A positive correlation of the QPO rms amplitude with energy is exhibited by 4U 1626–67, IGR J19294+1816, Cen X–3 and XTE J1858+034, …

Identification Of The Top Tess Objects Of Interest For Atmospheric Characterization Of Transiting Exoplanets With Jwst, B. J. Hord, E. M.-R. Kempton, T. M. Evans-Soma, D. W. Latham, D. R. Ciardi, D. Dragomir, K. D. Colón, G. Ross, A. Vanderburg, Z. L. De Beurs, K. A. Collins, C. N. Watkins, J. Bean, N. B. Cowan, T. Daylan, C. V. Morley, J. Ih, D. Baker, K. Barkaoui, N. M. Batalha, A. Behmard, A. Belinski, Z. Benkhaldoun, P. Benni, K. Bernacki, A. Bieryla, A. Binnenfeld, P. Bosch-Cabot, F. Bouchy, V. Bozza, R. Brahm, L. A. Buchhave, M. Calkins, A. Chontos, C. A. Clark, R. Cloutier, M. Cointepas, K. I. Collins, D. M. Conti, I. J. M. Crossfield, F. Dai, J. P. De Leon, G. Dransfield, C. Dressing, A. Dustor, G. Esquerdo, P. Evans, S. B. Fajardo-Acosta, J. Fiołka, R. Forés-Toribio, A. Frasca, A. Fukui, B. Fulton, E. Furlan, T. Gan, D. Gandolfi, M. Ghachoui, S. Giacalone, E. A. Gilbert, M. Gillon, E. Girardin, E. Gonzales, F. Grau Horta, J. Gregorio, M. Greklek-Mckeon, P. Guerra, J. D. Hartman, C. Hellier, I. Helm, K. G. Hełminiak, T. Henning, M. L. Hill, K. Horne, A. W. Howard, S. B. Howell, D. Huber, G. Isopi, E. Jehin, J. M. Jenkins, Eric L.N. Jensen, M. C. Johnson, A. Jordán, S. R. Kane, J. F. Kielkopf, V. Krushinsky, S. Lasota, E. Lee, P. Lewin, J. H. Livingston, J. Lubin, M. B. Lund, F. Mallia, C. R. Mann, G. Marino, N. Maslennikova, B. Massey, R. Matson, E. Matthews, A. W. Mayo, T. Mazeh, K. K. Mcleod, E. J. Michaels, T. Močnik, M. Mori, G. Mraz, J. A. Muñoz, N. Narita, K. Natarajan, L. D. Nielsen, H. Osborn, E. Palle, A. Panahi, R. Papini, P. Plavchan, A. S. Polanski, A. Popowicz, F. J. Pozuelos, S. N. Quinn, D. J. Radford, P. A. Reed, H. M. Relles, M. Rice, P. Robertson, J. E. Rodriguez, L. J. Rosenthal, R. A. Rubenzahl, N. Schanche, J. Schlieder, R. P. Schwarz, R. Sefako, A. Shporer, A. Sozzetti, G. Srdoc, C. Stockdale, A. Tarasenkov, T.-G. Tan, M. Timmermans, E. B. Ting, J. Van Zandt, Jp Vignes, I. Waite, N. Watanabe, L. M. Weiss, J. Wittrock, G. Zhou, C. Ziegler, S. Zucker

Physics & Astronomy Faculty Works

JWST has ushered in an era of unprecedented ability to characterize exoplanetary atmospheres. While there are over 5000 confirmed planets, more than 4000 Transiting Exoplanet Survey Satellite (TESS) planet candidates are still unconfirmed and many of the best planets for atmospheric characterization may remain to be identified. We present a sample of TESS planets and planet candidates that we identify as "best-in-class" for transmission and emission spectroscopy with JWST. These targets are sorted into bins across equilibrium temperature T_eq and planetary radius R_p and are ranked by a transmission and an emission spectroscopy metric (TSM and ESM, respectively) …

Sites Of Planet Formation In Binary Systems. I. Evidence For Disk−Orbit Alignment In The Close Binary Fo Tau, B. M. Tofflemire, L. Prato, A. L. Kraus, D. Segura-Cox, G. H. Schaefer, R. Akeson, S. Andrews, Eric L.N. Jensen, C. M. Johns-Krull, J. J. Zanazzi, M. Simon

Physics & Astronomy Faculty Works

Close binary systems present challenges to planet formation. As binary separations decrease, so do the occurrence rates of protoplanetary disks in young systems and planets in mature systems. For systems that do retain disks, their disk masses and sizes are altered by the presence of the binary companion. Through the study of protoplanetary disks in binary systems with known orbital parameters, we seek to determine the properties that promote disk retention and therefore planet formation. In this work, we characterize the young binary−disk system FO Tau. We determine the first full orbital solution for the system, finding masses of 0.35 …

A Search For Pulsars And An Exploration Of Dispersion Measure Within The Milky Way Galaxy, Emily Ware

Physics Undergraduate Honors Theses

A pulsar is a rapidly rotating neutron star which emits electromagnetic radiation from its magnetic poles. Upon detection from Earth, these signals have been dispersed in phase due to electron interactions in transit. The extent of this dispersion indicates information about both the distance to and the location of the pulsar, with respect to Earth and the Galactic plane. This project makes use of radio data from the 100m Robert C. Byrd Green Bank Telescope (GBT), presented in the form of prepfold plots assembled by the Pulsar Science Collaboratory (PSC). 1,007 of these plots were analyzed in order to determine …

Lhs 475 B: A Potential Venus Analog Orbiting A Nearby M Dwarf, K. Ment, D. Charbonneau, J. Irwin, J. G. Winters, E. Pass, A. Shporer, K. A. Collins, K. I. Collins, Eric L.N. Jensen, R. P. Schwarz, K. Horne, Z. Essack, V. B. Kostov, M. Kunimoto, A. Levine, S. Seager, R. Vanderspek, J. N. Winn

Physics & Astronomy Faculty Works

Based on photometric observations by TESS, we present the discovery of a potential Venus analog transiting LHS 475, an M3 dwarf located 12.5 pc from the Sun. The mass of the star is 0.274 ± 0.015 M_☉. The planet, originally reported as TOI 910.01, has an orbital period of 2.0291010 ± 0.0000017 days and an estimated radius of 0.975 ± 0.058 R_⊕. We confirm the validity and source of the transit signal with MEarth and Las Cumbres Observatory Global Telescope ground-based follow-up photometry. We present radial velocity data from CHIRON that rule out massive companions. In …

Remnant Polarization And Structural Arrangement In P(Vdf-Trfe) Electrospun Fiber Meshes Affect Osteogenic Differentiation Of Human Mesenchymal Stromal Cells, Bahareh Azimi, Massimiliano Labardi, Mohammad Sajad Sorayani Bafqi, Teresa Macchi, Claudio Ricci, Veronica Carnicelli, Lorenzo Scarpelli, Istiak Hussain, Francesca Matino, Mohammed Uddin

Physics & Astronomy Faculty Publications

Highlights

• The type of solvent had noticeable effects on morphology and piezoelectric properties of P(VDF-TrFE) electrospun fibers.

• Using MEK as a solvent and specific environmental conditions led to the obtainment of surface nanopores.

• Uniaxially aligned fibers exhibited higher β phase and mechanical properties than random ones.

• Randomly oriented fibers had higher remnant piezoelectric properties (Vout, d31 piezoelectric coefficient) than aligned ones.

• Human mesenchymal stem cells cultured on randomly oriented fibers showed an accelerated osteogenic differentiation.

Abstract

Many tissues and cells are influenced by mechano-electric stimulation, thus the application of piezoelectric materials has recently received considerable attention in tissue engineering. …

Search For Gravitational-Wave Transients Associated With Magnetar Bursts In Advanced Ligo And Advanced Virgo Data From The Third Observing Run, R. Abbott, Michael G. Benjamin, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

Gravitational waves are expected to be produced from neutron star oscillations associated with magnetar giant flares and short bursts. We present the results of a search for short-duration (milliseconds to seconds) and long-duration (∼100 s) transient gravitational waves from 13 magnetar short bursts observed during Advanced LIGO, Advanced Virgo, and KAGRA's third observation run. These 13 bursts come from two magnetars, SGR 1935+2154 and Swift J1818.0−1607. We also include three other electromagnetic burst events detected by Fermi-GBM which were identified as likely coming from one or more magnetars, but they have no association with a known magnetar. No magnetar giant …

The Jwst Early Release Science Program For Direct Observations Of Exoplanetary Systems. V. Do Self-Consistent Atmospheric Models Represent Jwst Spectra? A Showcase With Vhs 1256-1257 B, Simon Petrus, Niall Whiteford, Polychronis Patapis, Beth A. Biller, Andrew Skemer, Sasha Hinkley, Genaro Suárez, Paulina Palma-Bifani, Caroline V. Morley, Pascal Tremblin, Benjamin Charnay, Johanna M. Vos, Jason J. Wang, Jordan M. Stone, Mickaël Bonnefoy, Gaël Chauvin, Brittany E. Miles, Aarynn L. Carter, Anna Lueber, Christiane Helling, Ben J. Sutlieff, Markus Janson, Eileen C. Gonzales, Kielan K.W. Hoch, Olivier Absil, William O. Balmer, Anthony Boccaletti, Mariangela Bonavita, Mark Booth, Brendan P. Bowler, Et Al, Kimberly Ward-Duong

Astronomy: Faculty Publications

The unprecedented medium-resolution (R λ ∼ 1500-3500) near- and mid-infrared (1-18 μm) spectrum provided by JWST for the young (140 ± 20 Myr) low-mass (12-20 M Jup) L-T transition (L7) companion VHS 1256 b gives access to a catalog of molecular absorptions. In this study, we present a comprehensive analysis of this data set utilizing a forward-modeling approach applying our Bayesian framework, ForMoSA. We explore five distinct atmospheric models to assess their performance in estimating key atmospheric parameters: T eff, log(g), [M/H], C/O, γ, f sed, and R. Our findings reveal that each parameter’s estimate is significantly influenced by factors …

Modeling The Spatiotemporal Variations Of The Magnetic Field In Active Regions On The Sun Using Deep Neural Networks, Godwill Asare Mensah Mensah

Open Access Theses & Dissertations

Solar active regions are areas on the Sun's surface that have especially strong magnetic fields. Active regions are usually linked to a number of phenomena that can have serious detrimental consequences on technology and, in turn, human life. Examples of these phenomena include solar flares and coronal mass ejections, or CMEs. The precise predictionof solar flares and coronal mass ejections is still an open problem since the fundamental processes underpinning the formation and development of active regions are still not well understood. One key area of research at the intersection of solar physics and artificial intelligence is deriving insights from …

Toi-1135 B: A Young Hot Saturn-Size Planet Orbiting A Solar-Type Star, M. Mallorquín, N. Lodieu, V. J. S. Béjar, M. R. Zapatero Osorio, J. Sanz-Forcada, M. R. Alarcon, H. M. Tabernero, E. Nagel, K. A. Collins, D. R. Ciardi, M. Serra-Ricart, J. Orell-Miquel, K. Barkaoui, A. Burdanov, J. De Wit, M. E. Everett, M. Gillon, Eric L.N. Jensen, L. G. Murphy, P. A. Reed, B. Safonov, I. A. Strakhov, C. Ziegler

Physics & Astronomy Faculty Works

Despite the thousands of planets in orbit around stars known to date, the mechanisms of planetary formation, migration, and atmospheric loss remain unresolved. In this work, we confirm the planetary nature of a young Saturn-size planet transiting a solar-type star every 8.03 d, TOI-1135 b. The age of the parent star is estimated to be in the interval of 125-1000 Myr based on various activity and age indicators, including its stellar rotation period of 5.13 ± 0.27 days and the intensity of photospheric lithium. We obtained follow-up photometry and spectroscopy, including precise radial velocity measurements using the CARMENES spectrograph, which …

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

Spin Disorder Control Of Topological Spin Texture, Hongrui Zhang, Yu-Tsun Shao, Xiang Chen, Binhua Zhang, Tianye Wang, Fanhao Meng, Kun Xu, Peter Meisenheimer, Xianzhe Chen, Xiaoxi Huang, Piush Behera, Sajid Husain, Tiancong Zhu, Hao Pan, Yanli Jia, Nick Settineri, Nathan Giles-Donovan, Zehao He, Andreas Scholl, Alpha N'Diaye, Padraic Shafer, Archana Raja, Changsong Xu, Lane W. Martin, Michael F. Crommie, Jie Yao, Ziqiang Qiu, Arun Majumdar, Laurent Bellaiche, David A. Muller, Robert J. Birgeneau, Ramamoorthy Ramesh

Physics Faculty Publications and Presentations

Stabilization of topological spin textures in layered magnets has the potential to drive the development of advanced low-dimensional spintronics devices. However, achieving reliable and flexible manipulation of the topological spin textures beyond skyrmion in a two-dimensional magnet system remains challenging. Here, we demonstrate the introduction of magnetic iron atoms between the van der Waals gap of a layered magnet, Fe₃GaTe₂, to modify local anisotropic magnetic interactions. Consequently, we present direct observations of the order-disorder skyrmion lattices transition. In addition, non-trivial topological solitons, such as skyrmioniums and skyrmion bags, are realized at room temperature. Our work highlights …

How Do Nuclear Isomers Influence The Gamma-Ray Bursts In Binary Neutron Star Mergers?, Maria Babiuc-Hamilton, Joseph I. Powell

Physics Faculty Research

Neutron star mergers are astrophysical “gold mines,” synthesizing over half of the elements heavier than iron through rapid neutron capture nucleosynthesis. The observation of the binary neutron star merger GW170817, detected both in gravitational waves and electromagnetic radiation, marked a breakthrough. One electromagnetic component of this event, the gamma ray burst GRB 170817A, has an unresolved aspect: the characteristics of its prompt gamma-ray emission spectrum. In this work, we investigate that gamma-ray spectra in such GRBs may be influenced by de-excitations from isomeric transitions. Our study begins with a review of current knowledge on GRB structure and of r-process nucleosynthesis …

Survival Of Methanogens Desiccated On Mars Soil Simulants: Implications For Life On Mars, Lanee Knight

Biological Sciences Undergraduate Honors Theses

Because of Mars’s chemical features, it can be studied in the search for life and is a significant figure in the study of astrobiology (McKay, 2010). Dr. Kral’s laboratory studies methanogens, microorganisms in the domain Archaea, as possible life forms on Mars. Since some methanogens can withstand harsh environmental conditions and emit methane as a waste product, the growth of these microorganisms can be used as an indicator of potential life in the Mars subsurface (Kral et al., 1998). In this research, four methanogens, Methanothermobacter wolfeii, Methanobacterium formicicum, Methanosarcina barkeri, and Methanococcus maripaludi were desiccated in the …

To The Torus And Beyond: An X-Ray Study Of Agn Tori Morphology, Andrealuna Pizzetti

All Dissertations

Active Galactic Nuclei (AGN) are among the Universe's most energetic and powerful objects, fueled by an accreting supermassive black hole (SMBH) at the host galaxy's center, surrounded by a toroidal structure of dusty gas. Ultraviolet photons arising from the accretion disk get up-scattered to X-rays via inverse Compton scattering by hot electrons close to the accretion disk. Being produced in the very center of the AGN, X-ray photons are powerful messengers that probe the physics of the accretion system and the matter in the surroundings. The torus, formerly considered homogeneous, appears to be a more complex structure of clouds with …

Local Map Of The Interstellar Fuv Field, David Lomeli

Open Access Theses & Dissertations

The strength of the far-ultraviolet field is an important parameter in determining the chemistry that takes place in star-forming regions. FUV radiation is produced by bright stars in the galaxy and absorbed by interstellar dust. By using newly available maps of the dust distribution, in conjunction with catalogs of stellar positions and spectra, we created a local map of the FUV field ranging from 6-13.6 eV. We find a value of 6.57*10^-14 erg/cm^3 at the location of the Sun. This value, alongside its spectra, follow previous measurements and estimates of the FUV field at the Sun. We further study the …

Biomass Estimation Of Mature Mangrove Trees In The Uae Using Spaceborne Remote Sensing Techniques, Yasmine Ashraf Heikal

Theses

Mangrove forest ecosystems play an essential role in diminishing the effects of climate change caused by the increase in carbon dioxide in the atmosphere. Estimating mangrove forest aboveground biomass (AGB) and hence aboveground carbon (AGC) can assist in decision-making for conservation, sustainable use, and protection of these forests. The goal of this research project was to map the AGB of mangrove forests along the coasts of the United Arab Emirates (UAE) with the aid of Landsat-8-9 satellite imagery data acquired in September 2023. 12 AGB estimation models were developed based on the combination of in situ measurements and Landsat-8-9 derived …

Dynamical Studies Of Misaligned Circumbinary Disks, Ian C. Rabago

UNLV Theses, Dissertations, Professional Papers, and Capstones

Binary stars are common outcomes of the star formation process, with nearly half of Sun-like stars forming as part of a binary pair. The presence of a second star adds additional complexity and dynamical effects to the planet formation process in the surrounding circumbinary disk. In this work, I investigate the behavior of a circumbinary disk using hydrodynamic modeling, specifically in the case where the disk is misaligned to the binary orbital plane. Around eccentric binaries, highly inclined disks can align themselves perpendicular to the binary orbital plane. These "polar disks'' can produce vortices and spiral arms when the disk …

Better Light Than Never: A New Radiative Mechanism For Observing Binary Black Holes, Paul Rioles

Graduate Masters Theses

Black holes are notoriously elusive, they are impossible to observe directly, and cur- rent methods of extracting information from behind their cosmic camouflage are both limited in number and experimentally difficult. The scope of this investigation is to ex- plore a proposed novel radiative mechanism for active similar mass binary black holes, affording new observational methods to investigate frequency inspirals of BH mergers. The explored mechanism is a result of each BH’s accretion of the surrounding plasma, creating voids that orbit throughout the plasma. The significant results described in this thesis include expressions for the frequency, power radiated per unit …

Understanding Disk Substructures With 3d Self-Consistent Thermodynamics, Shangjia Zhang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Protoplanetary disks are birthplaces of planets. The past decade witnessed a great advance- ment in disk observations by Atacama Large Millimeter Array (ALMA) and extreme adaptive optics (ExAOs). Hundreds of disks have been observed at high angular resolutions and revealed rich substructures (e.g., gaps/rings) at midplane and atmosphere, at least part of which are per- turbed by planets. Deep understanding of disk physics has a great potential to unveil more young planets from substructures and distinguish those that are not caused by planets. I worked on con- straining young planet populations using planet-disk interaction simulations and substructures and self-consistent treatment …

Algorithm-Based Linearly Graded Compositions Of Gesn On Gaas (001) Via Molecular Beam Epitaxy, Calbi Gunder, Mohammad Zamani-Alavijeh, Emmanuel Wangila, Fernando Maia De Oliveira, Aida Sheibani, Serhii Kryvyi, Paul C. Attwood, Yuriy I. Mazur, Shui-Qing Yu, Gregory J. Salamo

Physics Faculty Publications and Presentations

The growth of high-composition GeSn films in the future will likely be guided by algorithms. In this study, we show how a logarithmic-based algorithm can be used to obtain high-quality GeSn compositions up to 16% on GaAs (001) substrates via molecular beam epitaxy. Herein, we use composition targeting and logarithmic Sn cell temperature control to achieve linearly graded pseudomorph Ge_1−xSn_x compositions up to 10% before partial relaxation of the structure and a continued gradient up to 16% GeSn. In this report, we use X-ray diffraction, simulation, secondary ion mass spectrometry, and atomic force microscopy to analyze and …

Unraveling The Physics Of Quasar Jets Using Hst Polarimetry, Devon Clautice

Theses and Dissertations

We present a multiwavelength study of three high-power FR II (quasar) jets -- 3C 273, PKS 0637-752, and 1150+497 -- with an emphasis on new high-quality Hubble Space Telescope (HST) optical polarimetry and Chandra X-ray Observatory imaging. Relativistic jets from active galactic nuclei transport energy and mass from the supermassive black hole’s accretion region out to Megaparsec-scale lobes, with effects that feedback into galaxy formation and cluster energetics. We build on recent work which has called into question our fundamental understanding of FR II jet physics, and suggest that highly-efficient particle acceleration must be taking place in situ …

The Gravitational Wave Peep: Improved Modeling Of Highly Eccentric Emris For Lisa Signal Confusion Noise, Daniel Joseph Oliver

Graduate Theses and Dissertations

Scattering events around a massive black hole will occasionally toss a stellar-mass compact object into an orbit around the massive black hole, beginning an extreme mass ratio inspiral. The early stages of such a highly eccentric orbit will not produce detectable gravitational waves as the source will only be in a suitable frequency band briefly when it is close to periapsis during each long-period orbit. This burst of emission, firmly in the millihertz band, is the gravitational wave peep. While a single peep is not likely to be detectable, if we consider an ensemble of such subthreshold sources, spread across …

Mapping Star Formation Histories In Nearby Galaxies To Source Lyman Continuum Photon Escape, Katie Kudla '24

Engineering & Physics Student Scholarship

Katie Kudla ’24, Physics major
Faculty Mentor: Dr. Joseph Ribaudo, Engineering and Physics

Investigation Of Surface Chemistry From Electron Irradiation Of Synthetic Schreibersite, Tyler Davis

Master's Theses

While phosphorus is one of the key elements for life on Earth, it has relatively low abundance in extraterrestrial environments, making it a target for astronomers and astrobiologists interested in the possibility of life beyond our planet. Schreibersite (Fe,Ni)₃P is one of the first P-containing minerals to condense during planetary cooling and one of the primary P-containing minerals in iron and stony-iron meteorites. Therefore, it is a likely P-bearing mineral in cometary cores and dust grains within the interstellar medium and circumstellar envelopes. Experiments in this project were performed with the aim of observing the formation of small …

Models Of Low Mass Stars As Physical Labratories, Emily M. Boudreaux

Dartmouth College Ph.D Dissertations

Low mass stars account for approximately 70 percent of the stellar populations (Conroy & Van Dokkum, 2012); yet, due to their small sizes and cool temperatures they account for only a small fraction of the galaxies luminosity function (Laughlin et al., 1997). Moreover, due to the lack of laboratory conditions available to astronomy and astrophysics low mass stars can provide a rare controlled environment for calibrations of numerical models. Consequently, across multiple domains there has been significant interest in these key astronomical objects. In this thesis I present three projects which have further revealed properties of low mass stars and …