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UNLV Theses, Dissertations, Professional Papers, and Capstones

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Full-Text Articles in Physical Sciences and Mathematics

Stoichiometric Determination Of Hydride Materials At Extreme Conditions, Gregory Alexander Smith May 2023

Stoichiometric Determination Of Hydride Materials At Extreme Conditions, Gregory Alexander Smith

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hydrogen was predicted to be a high-temperature superconductor at near-megabar conditions in 1968,[1] but only recently was been experimentally observed.[2] This is due to the extraneous metrological constraint of requiring 5 megabars of pressure to stabilize. A more practical approach for synthesis of high-temperature superconductors has been pro-posed through the use of hydride compounds. Recently, a surge of rare earth hydrides have achieved critical superconducting transition temperatures (T_C ) close to room temperature.[3, 4, 5, 6] However, due to limitations of the necessary instrumentation to achieve megabar pressures, many techniques traditionally used to measure stoichiometry are unavailable.Three works presented in …


Dea2uth: A Decentralized Authentication And Authorization Scheme For Secure Private Data Transfer, Phillipe Austria May 2023

Dea2uth: A Decentralized Authentication And Authorization Scheme For Secure Private Data Transfer, Phillipe Austria

UNLV Theses, Dissertations, Professional Papers, and Capstones

The sharing of private information is a daunting, multifaceted, and expensive undertaking. Furthermore, identity management is an additional challenge that poses significant technological, operational, and legal obstacles. Present solutions and their accompanying infrastructures rely on centralized models that are susceptible to hacking and can hinder data control by the rightful owner. Consequently, blockchain technology has generated interest in the fields of identity and access control. This technology is viewed as a potential solution due to its ability to offer decentralization, transparency, provenance, security, and privacy benefits. Nevertheless, a completely decentralized and private solution that enables data owners to control their …


Desert Spring Prokaryotes And Benthic Macroinvertebrates: Geological And Ecological Controls, Ariel D. Friel May 2023

Desert Spring Prokaryotes And Benthic Macroinvertebrates: Geological And Ecological Controls, Ariel D. Friel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Desert springs are aquatic oases, being considered among the most diverse and imperiled ecosystems on Earth. Despite the ecological significance and threatened status of desert springs, few studies have surveyed the microorganisms in these systems or their interactions with other community members. The primary goal of this dissertation was to describe the major controls influencing the community ecology of prokaryotic and BMI communities in cold- and moderate-temperature desert springs of the southern hydrographic Great Basin. Chapter 1 provides a broad overview of spring ecosystems and of each chapter included in this dissertation. Chapter 2 documents the first-ever, regional-scale survey of …


Solving Boundary Value And Initial Boundary Value Problems Of Partial Differential Equations Using Meshless Methods, Adam Johnson May 2023

Solving Boundary Value And Initial Boundary Value Problems Of Partial Differential Equations Using Meshless Methods, Adam Johnson

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this dissertation, the methods of fundamental solutions (MFS) and the methods of particular solutions (MPS) are used to solve the boundary value problems of the Poisson and Helmholtz equations, where the particular solutions of the Poisson and Helmholtz equations in [13, 14] are used. Then the initial boundary value problems of the diffusion and wave equations are discretized into a sequence of boundary value problems of the Helmholtz equation by using either the Laplace transform or time difference methods along the lines of [8]. The Helmholtz problems are solved consequently in an iterative manner which leads to the solution …


Joint Constraints On Kepler-36 From Kepler And New Keck-Hires Data, Nicholas Juliano May 2023

Joint Constraints On Kepler-36 From Kepler And New Keck-Hires Data, Nicholas Juliano

UNLV Theses, Dissertations, Professional Papers, and Capstones

I analyze new HIRES Radial Velocity (RV) data in conjunction with transit mid-times and uncertainties from the full 17 quarters of Kepler data to reassess the orbital parameters of the Kepler-36 system. Six additional RV measurements were taken by the Keck-HIRES spectrograph from September 21, 2021 to October 11, 2021. I carry out a differential evolution Markov Chain Monte Carlo-based (DEMCMC) analysis to infer improved orbital elements for the two known planets in the system. Leveraging additional information provided by the new RV measurements, I extend this DEMCMC analysis to a possible three-planet configuration. I explore the likelihood of a …


Critical Metals: From Granitic Pegmatites To The Anthropogenic Cycle, Dalton Mccaffrey May 2023

Critical Metals: From Granitic Pegmatites To The Anthropogenic Cycle, Dalton Mccaffrey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Critical metals are vital to the functionality of the modern world. The increased diversity and usage intensity of these commodities in defense-related and strategic technologies (e.g., jet engines, rocket assemblies), modern infrastructure and products (e.g., high-strength steel, cellular phones, laptop computers), and energy-related, low-emissions technologies (e.g., nuclear reactors, solar panels, wind turbines, hybrid and electric vehicles) has drastically increased our reliance on critical metals and, thus, the United States (and global) exposure to supply restrictions. Granitic pegmatites are unique mineral deposits that represent a past, present and future resource for many (approximately half) of these critical resources. Even with the …


Metastability And Degradation In Cu(In,Ga)Se2 Thin-Film Solar Cells, Mohsen Jahandardoost May 2023

Metastability And Degradation In Cu(In,Ga)Se2 Thin-Film Solar Cells, Mohsen Jahandardoost

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cu(In,Ga)(S,Se)2 or CIGS is a thin-film semiconductor that has shown a device efficiency of 23.35% and 24.2% for single-junction and perovskite/CIGS tandem solar cells, respectively. CIGS offers promising properties such as tunable bandgap and ease of processing making them great candidates for thin-film tandem devices. However, knowledge of the effect of material defects, buffer materials, and post-deposition treatment (PDT) on degradation and metastability behavior in these devices is not well understood.In this dissertation, metastability and long-term degradation of CIGS thin-film solar cells have been investigated under combinatorial stress factors of heat, light, and voltage bias to systematically understand the effect …


Spectroscopic Studies On Silicon And Chalcopyrite Materials For Solar Energy Applications, Amandee Hua May 2023

Spectroscopic Studies On Silicon And Chalcopyrite Materials For Solar Energy Applications, Amandee Hua

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this dissertation, silicon-based materials for photovoltaics and chalcopyrite-based materials for photoelectrochemical water splitting are investigated using various spectroscopic and microscopic techniques. Although silicon dominates the photovoltaic market, further improvement can be made by using an alternative low temperature passivation approach. Currently, thermally grown SiO2 passivation is commonly used for silicon solar cells. However, this technique requires high processing temperatures (>800 °C), which increases the thermal budget, potentially decreases the bulk quality of Si, and can lead to difficulties in implementing in production lines. Here, a S-based passivation approach is studied that require lower processing temperatures of ~550 °C. …


Hydrogeologic Heterogeneity Identification: Using Inverse Modeling Of Synthetic Borehole Temperatures To Predict Groundwater Flux, Kevin Heintz Dec 2022

Hydrogeologic Heterogeneity Identification: Using Inverse Modeling Of Synthetic Borehole Temperatures To Predict Groundwater Flux, Kevin Heintz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Heat has been effectively used as a groundwater tracer for decades, and high-resolution temperature data can better identify and quantify discrete flow zones. Refinements to the numerical modeling of advective heat transfer in borehole temperature sensing deployments can improve understanding of dynamic hydrogeologic systems. In my thesis, I develop a novel two-dimensional coupled radial groundwater flow and heat transfer numerical model that considers intra-borehole vertical flow. To test the performance of this model, I used finite element analysis to generate synthetic data sets consisting of prescribed variable flow fields and resulting borehole temperatures. I input synthetic temperatures into the two-dimensional …


Calcite Spherulite Formations And Their Controls In Halophilic Bacterial Cultures, Zakaria Jibrin Dec 2022

Calcite Spherulite Formations And Their Controls In Halophilic Bacterial Cultures, Zakaria Jibrin

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study arose from an accidental discovery of calcite spherulites forming on colonies of various halophilic bacteria grown on solid Luria-Bertani medium made containing water from a brine pool in Death Valley, their natural habitat. Further studies with a large spherulite forming bacteria, Pseudoalteromonas haloplanktis, showed that calcite precipitation conditions were the consequence of bacteria using amino acids as a source of carbon and energy, a metabolism that produces NH3 and CO2 waste products. NH3 raises the pH of the medium, turning CO2 into CO32-. Calcium in the natural brine combines with CO32-. The resulting spherulitic calcite precipitation is nano-acicular …


Use Of Healthcare Utilization Records For Analyzing Trends In Clinical Toxoplasmosis: A Comparison Of Nevada And The United States, Elijah Kreutzer Dec 2022

Use Of Healthcare Utilization Records For Analyzing Trends In Clinical Toxoplasmosis: A Comparison Of Nevada And The United States, Elijah Kreutzer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Toxoplasmosis, a zoonotic disease caused by the parasitic protist Toxoplasma gondii, is a ubiquitous, global public health concern with a wide variety of clinical manifestations. Surveillance for the disease is lacking even in developed countries, and what surveillance is present most often focuses on pregnant women. This research investigated trends in clinical toxoplasmosis in Nevada and nationally to address the lack of knowledge concerning how Nevada discharges compare to national discharges in cases of toxoplasmosis. Specifically, this research sought to determine what characterizes toxoplasmosis in Nevada across inpatient, outpatient, and emergency department settings, as well as how these cases differ …


Estimation Of The Parameters In A Mixture Of Two Normal Distributions And The Generalized Pivotal Quantity Method, Md Faruk Hossain Dec 2022

Estimation Of The Parameters In A Mixture Of Two Normal Distributions And The Generalized Pivotal Quantity Method, Md Faruk Hossain

UNLV Theses, Dissertations, Professional Papers, and Capstones

A pivotal quantity is a random variable that is a function of both the random data and the unknown population parameters and whose probability distribution does not depend on any of the unknown parameters. The population parameters here may include nuisance parameters. Historically, pivotal quantities have been used for the construction of test statistics for hypothesis testing of some of these unknown parameters. They have also been used for the construction of confidence intervals for some of these parameters.Generalized pivotal quantities (GPQ) were introduced by Tsui and Weerahandi (1989) and Weerahandi (1993). A GPQ is a function, not only of …


Towards The Electronic Response Of Carbon-Based Van Der Waals Heterostructures In A Diamond Anvil Cell, George Thomas Foskaris Dec 2022

Towards The Electronic Response Of Carbon-Based Van Der Waals Heterostructures In A Diamond Anvil Cell, George Thomas Foskaris

UNLV Theses, Dissertations, Professional Papers, and Capstones

The nanoscale regime of materials has been at the forefront of research and interest in condensed matter physics for many years. In a merger of the fields of two-dimensional (2D) materials and high pressure physics, we present an investigation of the electronic response of carbon-based, van der Waals (vdW) heterostructures in a diamond anvil cell (DAC). Combining these fields presents us with the ability to study the characteristics of such systems both optically, and through electrical transport. Properties such as conductance, band structure, and layer number are considered. The samples in this study are assembled using exfoliation and stacking techniques …


Transient Sources And How To Study Them: Selected Topics In Multi-Messenger Astronomy, Jiawei Luo Dec 2022

Transient Sources And How To Study Them: Selected Topics In Multi-Messenger Astronomy, Jiawei Luo

UNLV Theses, Dissertations, Professional Papers, and Capstones

The discovery of cosmic neutrino flux by IceCube, and the multi-messenger observations of gravitational event GW170817 ushered in the era of multi-messenger astronomy. Since the Universe itself is a natural laboratory, multi-messenger astronomy can help us study the most extreme physics processes in great detail. In this dissertation, we touch on some of the currently unanswered questions involving different types of transient sources and different “messengers” of multi-messenger astronomy. We employ a variety of analysis methods, including machine learning, a method that has not yet been widely adopted in astronomy but is rapidly gaining momentum.We start this dissertation with Chapter …


Mesozoic Sevier Thrusts Overprinted By Miocene-Quaternary Left-Lateral Deformation: Structures And Tectonism Of The Kane Springs Wash Region, Nevada, Andrew Reid Dec 2022

Mesozoic Sevier Thrusts Overprinted By Miocene-Quaternary Left-Lateral Deformation: Structures And Tectonism Of The Kane Springs Wash Region, Nevada, Andrew Reid

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recognizing how rifts develop through space and time is vital to enrich our understanding of continental breakup. Rifts are commonly segmented by transfer or accommodations zones that form as the rift develops due to differences in the onset, direction, magnitude, or rates of extension on either side of the transfer or accommodation zone. The Basin and Range province is a wide rift where Cenozoic extension overprints and exposes earlier Mesozoic Sevier fold-thrust belt shortening structures. This exposure allows Sevier thrust correlations between individual mountain ranges and use of these shortening structures to study rift segmentation by strike-slip transfer faults. The …


Day ‘N’ Nite: Habitability Of Tidally Locked Planets With Sporadic Rotation, Cody James Shakespeare Dec 2022

Day ‘N’ Nite: Habitability Of Tidally Locked Planets With Sporadic Rotation, Cody James Shakespeare

UNLV Theses, Dissertations, Professional Papers, and Capstones

Tidally locked worlds provide a unique opportunity for constraining the climates of detected exoplanets. They are unique in that few exoplanet spin and obliquity states are known or will be determined in the near future. The TRAPPIST-1 exoplanet system has multiple habitable zone planets that, in the past, have been presumed to be tidally locked. However, a recent study shows the dynamical conditions present in the TRAPPIST-1 system make rotation and large librations possible spin states for these planets. I confirm the tendency for these planets to sporadically transition from tidally locked libration to slow rotation using N-body simulations independent …


Jiapi: A Type Checker Generator For Statically Typed Languages, Benjamin Cisneros Merino Dec 2022

Jiapi: A Type Checker Generator For Statically Typed Languages, Benjamin Cisneros Merino

UNLV Theses, Dissertations, Professional Papers, and Capstones

Type systems are a key characteristic in the context of the study of programming languages. They frequently offer a simple, intuitive way of expressing and testing the fundamental structure of programs. This is especially true when types are used to provide formal, machine-checked documentation for an implementation. For example, the absence of type errors in code prior to execution is what type systems for static programming languages are designed to assure, and in the literature, type systems that satisfy this requirement are referred to as sound type systems. Types also define module interfaces, making them essential for achieving and maintaining …


Quantifying The Effect Of Disturbance On Native Mojave Desert Shrubs, Tamara J. Wynne Dec 2022

Quantifying The Effect Of Disturbance On Native Mojave Desert Shrubs, Tamara J. Wynne

UNLV Theses, Dissertations, Professional Papers, and Capstones

Disturbance can come in many different forms. In our studies, we looked at the impact of a solar photovoltaic facility on native plants growing inside and outside of the facility, alteration in precipitation (simulated) on four native shrubs and the impact of applying supplemental water as a function of volume and frequency to establish native shrubs such as might occur at restoration sites. Disturbance is becoming a more common phenomenon in many ecosystems throughout the world, increasing the need for studies that quantify the impact at the plant and ecosystem level. Each research project revealed different plant responses, such as …


Real–Time Semantic Segmentation For Railway Anomalies Analysis, Paul Stanik Iii Dec 2022

Real–Time Semantic Segmentation For Railway Anomalies Analysis, Paul Stanik Iii

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the past few years, computer vision has made huge jumps due to deep learning which leverages increased computational power and access to data. The computer vision community has also embraced transparency to accelerate research progress by sharing open datasets and open source code. Access to large scale datasets and benchmark challenges propelled and opened the field. The autonomous vehicle community is a prime example. While there has been significant growth in the automotive vision community, not much has been done in the rail domain. Traditional rail inspection methods require special trains that are run during down time, have sensitive …


Display Applications For Grating Angle Magnification Accelerated Angular Scanners, Daniel Jesus Valdes Dec 2022

Display Applications For Grating Angle Magnification Accelerated Angular Scanners, Daniel Jesus Valdes

UNLV Theses, Dissertations, Professional Papers, and Capstones

This work includes experimental demonstrations of grating angle magnification accelerated optical beam scanners. Diffraction grating scanners governed by the grating equation can have scan speed advantages over the flat mirror bound by Snell's law of reflection. Scan speed enhancement of 750% was achieved with a 635nm laser and 1800 groove/mm diffraction grating configuration thanks to the grating angle magnification. A three-color diffraction grating scanner shows identical results at larger scan angles. Tunable acceleration speed is a feature enabled by the diffraction grating scanner to operate in a high-speed scanning region and/or high-resolution scanning region depending on the demands of the …


What Can General Chemistry Students Learn From External Representations Of Acid- Base Titrations?, Nicole Baldwin Dec 2022

What Can General Chemistry Students Learn From External Representations Of Acid- Base Titrations?, Nicole Baldwin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Laboratory activities are a prevalent and essential part of chemistry learning because of their potential to help students develop problem solving abilities, visualize chemistry concepts learned in lecture, and gain practical skills. However, learning in the laboratory environment is not without its challenges. For example, cookbook-style chemistry laboratories can promote superficial learning, and cognitive overload can result from the study of new concepts and the use of new procedures in this environment. Multiple pedagogies and supports have been developed to address challenges such as these. The current research focuses upon external representations that are commonly used to support learning in …


Retrospective Varying Coefficient Association Analysis Of Longitudinal Binary Traits, Gang Xu Dec 2022

Retrospective Varying Coefficient Association Analysis Of Longitudinal Binary Traits, Gang Xu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many genetic studies contain rich information on longitudinal phenotypes that require powerful analytical tools for optimal analysis. Genetic analysis of longitudinal data that incorporates temporal variation is important for understanding the genetic architecture and biological variation of complex diseases. Most of the existing methods assume that the contribution of genetic variants is constant over time and fails to capture the dynamic pattern of disease progression. However, the relative influence of genetic variants on complex traits fluctuates over time.We developed several tests to fill the gap of analyzing time-varying genetic effects in longitudinal GWAS for binary traits. First, we propose a …


Characterization Of The Isothermal Titration Calorimetry Single Injection Method Using T4 Polynucleotide Kinase As A Model System For Kinases, Rebecca Chaehee Lim Dec 2022

Characterization Of The Isothermal Titration Calorimetry Single Injection Method Using T4 Polynucleotide Kinase As A Model System For Kinases, Rebecca Chaehee Lim

UNLV Theses, Dissertations, Professional Papers, and Capstones

Kinases are an important class of enzymes involved in the regulation of different cellular processes. The dysfunctional activity, either hyperactivity or inactivity, of kinases has been associated with many types of diseases, making kinases a major therapeutic target. As of 2020, more than 80 kinase inhibitors have been FDA-approved and have revolutionized the treatment for progressive disorders such as cancers and Alzheimer's diseases. However, there is always the possibility of developing severe side effects or resistance to drugs so the search for new therapeutics must continue with efficiency and accuracy.Isothermal titration calorimetry (ITC) is a state-of-the-art technique specialized in detecting …


The Metabolic Change Of Lipid Species In Stam Mice With Hepatocellular Carcinoma, Devin J. Peart Dec 2022

The Metabolic Change Of Lipid Species In Stam Mice With Hepatocellular Carcinoma, Devin J. Peart

UNLV Theses, Dissertations, Professional Papers, and Capstones

Primary liver cancer hepatocellular carcinoma (HCC) is the second leading cause of cancer death worldwide. In the US, primary liver cancer is the most rapidly increasing type of cancer due to increases in hepatitis B and C and the continued trend of greater and greater percentages of the population suffering from obesity, diabetes mellitus and metabolic syndrome. The prognosis for this disease is poor, with a 5-year survival rate of 26% as compared to only 2% when the cancer is metastatic. Unfortunately, current strategies for early detection of HCC, including routine CT imaging or alpha-fetoprotein biomarker, are suboptimal and tend …


Identification Of Factors Contributing To Traffic Crashes By Analysis Of Text Narratives, Cristian D. Arteaga-Sanchez Dec 2022

Identification Of Factors Contributing To Traffic Crashes By Analysis Of Text Narratives, Cristian D. Arteaga-Sanchez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The fatalities, injuries, and property damage that result from traffic crashes impose a significant burden on society. Current research and practice in traffic safety rely on analysis of quantitative data from crash reports to understand crash severity contributors and develop countermeasures. Despite advances from this effort, quantitative crash data suffers from drawbacks, such as the limited ability to capture all the information relevant to the crashes and the potential errors introduced during data collection. Crash narratives can help address these limitations, as they contain detailed descriptions of the context and sequence of events of the crash. However, the unstructured nature …


Trace Element Behaviors During Igneous Evolution And Hydrothermal Alteration Of An Evolved Rhyolite, The Blawn Formation, Wah Wah Mountains, Utah: Implications For Critical Metal Abundances In Highly Evolved Rhyolites, Drew William Barkoff Dec 2022

Trace Element Behaviors During Igneous Evolution And Hydrothermal Alteration Of An Evolved Rhyolite, The Blawn Formation, Wah Wah Mountains, Utah: Implications For Critical Metal Abundances In Highly Evolved Rhyolites, Drew William Barkoff

UNLV Theses, Dissertations, Professional Papers, and Capstones

A-type rhyolites and granites often contain elevated concentrations of the rare earth elements (REE) and many other critical trace elements relative to I- and S-type rhyolites and granites. Their trace element-enriched nature makes them potentially prospective bulk tonnage, low-grade resources of the REE and many other critical trace elements, including Li, Be, Mo, Sn, and W, but little work has been performed to delineate their economic potential. The 22.1 Ma Red Beryl Rhyolite (RBR) and the 18.3 Ma Tetons Rhyolite (TR) units of the Blawn Formation represent two A-type rhyolite domes located in the southern Wah Wah Mountains of Utah. …


Age And Genesis Of W-Mo-Cu Mineralization, Gold Hill, Utah, Nathan J. Carey Dec 2022

Age And Genesis Of W-Mo-Cu Mineralization, Gold Hill, Utah, Nathan J. Carey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Utah's Gold Hill mining district hosts a Jurassic felsic pluton (~80 km^2) that was emplaced into a Mississippian to Pennsylvanian carbonate-dominated sedimentary sequence and is spatially associated with numerous polymetallic mineral deposits. This study focuses on W-Mo-Cu mineralization at the Lucy L., Doctor, Yellow Hammer, Reaper, and Rustler deposits within the district. The new, detailed petrographic observations, mineral chemistry (on scheelite, molybdenite, chalcopyrite, magnetite, garnet, and pyroxene), and Re-Os molybdenite geochronological data presented here allows for the determination of key mineral associations and paragenesis, the characterization of deposit types and their evolution, and the constraining of the relative and absolute …


Along Strike Tectonic Evolution Of The Neogene Bermejo Foreland Basin And Eastern Precordillera Thrust Front, Argentina (30-32ºs), Zoey Catherine Plonka Dec 2022

Along Strike Tectonic Evolution Of The Neogene Bermejo Foreland Basin And Eastern Precordillera Thrust Front, Argentina (30-32ºs), Zoey Catherine Plonka

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Bermejo retroarc foreland basin system formed in flexural response to Miocene crustal thickening in the Andean orogenic system, specifically, the eastward propagation of the Precordillera fold-thrust belt and the basement-involved uplift of the Sierras Pampeanas. Previous work in the area has mainly focused on the mechanisms and expression of flat slab subduction and the structural geometry of the basement-involved Sierras Pampeanas and east-vergent Precordillera fold-thrust belt at depth. Much of this work has furthered the understanding of Bermejo basin evolution north of 31ºS, however debate still exists whether the N-S trending Bermejo basin evolved synchronously or asynchronously through time. …


Polar Alignment Of Massive Retrograde Circumbinary Discs, Charles Abod Aug 2022

Polar Alignment Of Massive Retrograde Circumbinary Discs, Charles Abod

UNLV Theses, Dissertations, Professional Papers, and Capstones

To understand the observed circumbinary planetary systems, we must first explain the dynamics of the circumbinary discs in which they formed. Observations of circumbinary discs show that misalignments to the binary orbital plane may be common. Here we investigate these systems by exploring the orbital dynamics of three-body systems and circumbinary discs. A test particle orbit around an eccentric binary has two stationary states in which there is no nodal precession: coplanar and polar. Nodal precession of a misaligned test particle orbit centres on one of these stationary states. A low mass circumbinary disc undergoes the same precession and moves …


Design And Fabrication Of An Apparatus For Tao High-Resolution Laser Spectroscopy, Timothy Chung Aug 2022

Design And Fabrication Of An Apparatus For Tao High-Resolution Laser Spectroscopy, Timothy Chung

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study, an apparatus for the high-resolution laser spectroscopy of molecules is designed and constructed. The apparatus is used to identify TaO transitions, but may be used for any other molecular species in the future. It will also later be used for experiments such as quantum logic spectroscopy, which are enabled by attachable chambers that can be supplied with molecules from the apparatus. Several considerations are made to improve the quality and longevity of the apparatus such as regulating the rovibrational states of the produced molecules, optimizing the linewidth of the ionization lasers, reducing noise from sources such as …