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2022

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Articles 18121 - 18150 of 18295

Full-Text Articles in Physical Sciences and Mathematics

Cycles Or Repetitions: A Quantitative Analysis Of Alluvial Bed Thicknesses, Kristopher D. Phillips Jan 2022

Cycles Or Repetitions: A Quantitative Analysis Of Alluvial Bed Thicknesses, Kristopher D. Phillips

WWU Graduate School Collection

Sedimentary strata display a range of repetitive patterns from interbedded lithofacies through recurring sequence stratigraphic systems tracts. Highly structured, large-scale patterns are commonly ascribed to cyclic allogenic forcings such as eustasy and climate. In contrast, autogenic processes are typically thought to impart stochastic noise or limited small-scale structure on stratigraphy. Recent studies indicate some autogenic processes in fluvial and fluvio-deltaic systems such as the large-scale compensational deposition (i.e., the tendency for a channel to occupy and fill topographic lows in a basin), can occur on spatiotemporal scales that may overlap with some allogenic forcings. These autogenic processes could impart deterministic, …


Sortase-Mediated Ligation To Investigate Large Idr-Containing Cytoskeletal Regulators, Melissa Oueld Es Cheikh Jan 2022

Sortase-Mediated Ligation To Investigate Large Idr-Containing Cytoskeletal Regulators, Melissa Oueld Es Cheikh

WWU Graduate School Collection

About 43% of eukaryotic proteins contain intrinsically disordered regions (IDRs) of 40 residues or longer. These proteins modulate key cellular functions such as transcription, translation, and signal transduction. Despite their vital roles, little is known about the properties of large disordered proteins due to the difficulties encountered studying them. Solution nuclear magnetic resonance (NMR) spectroscopy is a unique tool allowing for their analysis but traditionally requires uniform protein labeling with 15N and 13C isotopesresulting in convoluted spectra which obscure any meaningful information on their structures and interactions. To remedy this issue, we aim at developing a procedure to segmentally label …


Structural History Of The Formidable-Le Conte Mountain Area, North Cascades, Wa, Nyle Weldon Jan 2022

Structural History Of The Formidable-Le Conte Mountain Area, North Cascades, Wa, Nyle Weldon

WWU Graduate School Collection

A record of Permian to Tertiary polyphase deformation, metamorphism and magmatism is preserved in the Cascades River region of the North Cascades Crystalline Core, Washington. The tectonic history recorded here can be used to understand the deep crustal processes occurring within active convergent plate margins around the world. New structural and geochronologic data from this study are used to advance our understanding of terrane origin, accretion, and processes that altered and thickened the crust of the North Cascades.

The study focuses on several rock units within an accreted Permian-Jurassic island arc, the Chelan Mountains terrane, that was tectonized in Cretaceous …


Off-Channel Habitat Restoration Using Groundwater Infiltration Galleries In The Methow River Basin, Washington, Nicole Masurat Jan 2022

Off-Channel Habitat Restoration Using Groundwater Infiltration Galleries In The Methow River Basin, Washington, Nicole Masurat

WWU Graduate School Collection

Anthropogenic development in river floodplains has diminished the extent groundwater and surface water interact. This interaction plays an important role in the formation of floodplain habitats that provide essential refuge for stream biota when extreme seasonal conditions arise. To address the need for more off-channel habitat in the floodplain, a novel strategy of habitat construction was implemented by the Yakama Nation in the Methow River Basin. At two locations, groundwater infiltration galleries were installed in relic side channels disconnected from the mainstem by infrastructure. These installations collect subsurface flow and drain it to excavated channels connected to the mainstem channel …


Using Crystal Zoning, Thermobarometry, And Melts To Elucidate Koma Kulshan’S (Mt. Baker) Transcrustal Magma Storage System, Northern Cascade Arc, Brendan Garvey Jan 2022

Using Crystal Zoning, Thermobarometry, And Melts To Elucidate Koma Kulshan’S (Mt. Baker) Transcrustal Magma Storage System, Northern Cascade Arc, Brendan Garvey

WWU Graduate School Collection

Koma Kulshan (Mt. Baker) is classified as a high-threat volcano due to its past eruptive history and its proximity to populations, yet its eruptive products are understudied. Combining mineral chemistry from complexly zoned crystals with thermobarometry and thermodynamic modeling (MELTS) is a powerful way to provide constraints on magmatic processes beneath an active volcano. Up to four populations each of pyroxene, plagioclase, and olivine occur as phenocrysts and crystal clusters in the youngest (9.8 ka) lava flow at Koma Kulshan and represent four co-crystallizing assemblages derived from distinct magmas. These co-crystallizing assemblages are defined by petrologic observations and mineral chemistry …


Eruption Evolution Of West Mata Volcano, Ne Lau Basin Using Hydroacoustic And Video Data, Mikkel Shanice Louis Jan 2022

Eruption Evolution Of West Mata Volcano, Ne Lau Basin Using Hydroacoustic And Video Data, Mikkel Shanice Louis

WWU Graduate School Collection

West Mata Volcano located in the NE Lau Basin is the site of the deepest observed submarine volcanic eruption, 1,200 meters below sea level. In May 2009, a research cruise collected video data of two eruptive vents showcasing different eruption styles. During the same research cruise, a BprobeTM portable hydrophone was deployed at the summit of West Mata and collected data that coincides with video recorded at the vents during ROV dives. These data sets were correlated to better understand the spectral signatures associated with the two eruptive vents. Both vents were near the summit, about 50 meters apart, …


Responses Of The Symbiotic Sea Anemone Anthopleura Elegantissima To Microplastics, Robert Beck Jan 2022

Responses Of The Symbiotic Sea Anemone Anthopleura Elegantissima To Microplastics, Robert Beck

WWU Graduate School Collection

The Salish Sea, a large and complex fjord estuary, receives waters impacted by a watershed that includes 8 million people aggregated in several large urban and industrial centers. Microplastics, defined as plastic particles less than 5 mm in their largest dimension, are transported from this watershed into the Salish Sea where they are easily ingested by filter feeders, herbivores and predators. To measure effects of microplastics on one common and important intertidal species, we exposed the sea anemone Anthopleura elegantissima to polyester microfibers at concentrations of 0, 0.01, or 0.1 g/L in the laboratory and measured the responses of the …


Ecological Risk Assessment Of Tire Wear Particles In The San Francisco Bay Using A Bayesian Network Relative Risk Model, Emma E. Sharpe Jan 2022

Ecological Risk Assessment Of Tire Wear Particles In The San Francisco Bay Using A Bayesian Network Relative Risk Model, Emma E. Sharpe

WWU Graduate School Collection

Here we present an ecological risk assessment for a specific type of microplastic in the San Francisco Bay. There has been an increased interest in understanding and managing the impacts that microplastics may have on ecological systems because recent studies have shown that plastic particles are widespread in the environment and that exposure to these particles has toxicological effects. Until now, an ecological risk assessment for microplastics that meets the current standards for risk assessment, has not been completed. This study lays the groundwork for future ecological risk assessments of microplastics and identifies key uncertainties that need to be addressed. …


Living In Pele's Workshop: Using Community-Informed Planning To Address Housing Needs In Puna, Hawai'i, Taylor Webb Jan 2022

Living In Pele's Workshop: Using Community-Informed Planning To Address Housing Needs In Puna, Hawai'i, Taylor Webb

WWU Graduate School Collection

The purpose of this research project is to understand the ways in which the current land use regulations in Puna, Hawai’i have impacted accessibility to a variety of affordable housing forms. The 2018 Kīlauea eruption and COVID-19 pandemic have exacerbated issues in the community that were already prevalent in the area including rising housing costs, lack of housing options, and insufficient infrastructure and access to essential services. As more people continue to move into the Puna District, these issues are becoming intensified. With these complexities in mind, I utilized a mixed-method research approach to study both the physical and social …


Using Frog Embryo Teratogenesis Assay-Xenopus Laevis (Fetax) To Study Metals And Temperature As Multiple Stressors In Cascades Frog (Rana Cascadae), Adam Turner (Cockrill) Crispin Jan 2022

Using Frog Embryo Teratogenesis Assay-Xenopus Laevis (Fetax) To Study Metals And Temperature As Multiple Stressors In Cascades Frog (Rana Cascadae), Adam Turner (Cockrill) Crispin

WWU Graduate School Collection

Amphibian populations have been declining globally since at least the 1970s. In the western United States, disappearances have resulted in significant range contractions due to habitat loss, climate change, predation by non-native species, pesticide use, and disease, most recently by the fungal pathogen, Batrachochytrium dendrobatidis. Several recent studies have addressed amphibian population declines due to climate change, yet few studies have examined the interacting effects of climate change and metal contaminants as they relate to amphibians. Risks may be especially pronounced in amphibians that reside in high-alpine aquatic ecosystems, such as the Cascades frog (Rana cascadae), which may be affected …


Avian And Shallow Water Community Response To Pacific Herring (Clupea Pallasii) Spawn Events, Heidi Stewart Jan 2022

Avian And Shallow Water Community Response To Pacific Herring (Clupea Pallasii) Spawn Events, Heidi Stewart

WWU Graduate School Collection

Pacific Herring play a critical role in the food web of the Salish Sea. The Cherry Point stock, centered 30 miles north of Bellingham Bay, has declined roughly 97% since the 1970s. This massive decline is a point of concern for environmental and fishery managers and has led to research into both the initial decline and the stock’s inability to recover. One key data gap in need of research is whether the Cherry Point herring stock is experiencing increased predation from the nearshore fish, bird, and invertebrate community due to its unique late spawn timing and spawning behavior. To that …


Species Distribution And Abundance Of Bering Sea Tunicates With Implications For Coastal Food Security, Meghan Bugaj Jan 2022

Species Distribution And Abundance Of Bering Sea Tunicates With Implications For Coastal Food Security, Meghan Bugaj

WWU Graduate School Collection

The use of sessile macroinvertebrates as leading indicators of change in marine ecosystems makes them potentially valuable as a management tool for predicting habitat suitability for more mobile, commercially important fishes. In addition to potential use as an ecosystem indicator in fisheries management, tunicates are used as a food resource by some Alaska Native communities. Variability in abundance and distribution, driven by changing physical conditions in the Bering Sea, could impact food security for these communities. I used fishery-independent NOAA survey data from the Eastern Bering Sea summer surveys from 1987 to 2019 to examine abundance and distribution of several …


Modeling 21st Century Peak Streamflows In The Stillaguamish Watershed Using Dynamically Downscaled General Circulation Model Projections, James Marcell Robinson Jan 2022

Modeling 21st Century Peak Streamflows In The Stillaguamish Watershed Using Dynamically Downscaled General Circulation Model Projections, James Marcell Robinson

WWU Graduate School Collection

Climate change is projected to increase river flooding in the Puget Sound region of Washington State by reducing snowpack and yielding more intense storm events. Pairing meteorological forcings from general circulation models (GCMs) with a physically based hydrologic model is a robust method of assessing watershed response to projected climate. Before GCM forcings can be applied to regional hydrologic models, some form of downscaling or regionalization is required. Dynamical downscaling is a means of incorporating mesoscale atmospheric processes within GCM-informed boundary conditions. Here I apply climate projections, dynamically downscaled using the Weather Research and Forecasting model (WRF), to the Stillaguamish …


The Photochemical Evolution Of Dissolved Black Carbon In Snow: A Case Study From The North Cascades, Molly Peek Jan 2022

The Photochemical Evolution Of Dissolved Black Carbon In Snow: A Case Study From The North Cascades, Molly Peek

WWU Graduate School Collection

Black carbon (BC) is partially combusted organic material from natural and anthropogenic sources, and is a highly effective driver of melt in the cryosphere. BC has been found in both populated and remote areas around the globe. This study follows the evolution of UV-exposed dissolved BC (DBC) in the cryosphere using the Benzenepolycarboxylic Acid (BPCA) markers B4CA, B5CA, and B6CA. Samples were collected from Mount Baker, Washington, and from both an in situ field study and a controlled photodegradation study, both using natural and anthropogenic BC standards. Both natural and experimental samples had a dominance of B5CA relative to other …


Polarization Properties Of Millisecond Pulsars: Astrophysical Interpretations And Applications, Haley Megan Wahl Jan 2022

Polarization Properties Of Millisecond Pulsars: Astrophysical Interpretations And Applications, Haley Megan Wahl

Graduate Theses, Dissertations, and Problem Reports

Pulsars are some of the most extreme objects in the universe; their small yet incredibly predictable spin periods coupled with their strong magnetic fields make them ideal laboratories for study. Not only are they interesting objects themselves, but they can also help us probe different astrophysical environments, such as the interstellar magnetic field and the solar corona.

These stars are highly polarized, and that polarization comes into play in various fields of pulsar physics (such as constraining models of pulsar emission), but obtaining that polarization information can be difficult, as the polarization properties of the light can change as the …


Synthesis, Characterization, And Activation Of Pyridine Dipyrrolide Supported Vanadium-Nitrogen Multiple Bonds, Jordan Cruz Martinez Jan 2022

Synthesis, Characterization, And Activation Of Pyridine Dipyrrolide Supported Vanadium-Nitrogen Multiple Bonds, Jordan Cruz Martinez

Graduate Theses, Dissertations, and Problem Reports

The chemistry of coordination complexes of vanadium supported by pyridine di-pyrrolide pincer ligands was probed via the synthesis and investigation of a variety of compounds from the trivalent starting material, (MesPDPPh)VCl(thf)2. Under reducing conditions and subsequent addition of terpyridine, a redox transfer series (1-, 0, 1+) stemming from the neutral product (MesPDPPh)V(terpy) was isolated and characterized by X-ray crystallography. The precise bond lengths, in conjunction with bulk magnetic susceptibility, allowed for a detailed study of the redox non-innocence of polypyridyl ligands in these systems.

Metathesis of the halide starting material …


Structure-Dependent Characterizations Of Multistationarity In Mass-Action Reaction Networks, Galyna Voitiuk Jan 2022

Structure-Dependent Characterizations Of Multistationarity In Mass-Action Reaction Networks, Galyna Voitiuk

Graduate Theses, Dissertations, and Problem Reports

This project explores a topic in Chemical Reaction Network Theory. We analyze networks with one dimensional stoichiometric subspace using mass-action kinetics. For these types of networks, we study how the capacity for multiple positive equilibria and multiple positive nondegenerate equilibria can be determined using Euclidian embedded graphs. Our work adds to the catalog of the class of reaction networks with one-dimensional stoichiometric subspace answering in the affirmative a conjecture posed by Joshi and Shiu: Conjecture 0.1 (Question 6.1 [26]). A reaction network with one-dimensional stoichiometric subspace and more than one source complex has the capacity for multistationarity if and only …


Scaling Theory Of 3d Magnetic Reconnection X-Line Spreading, Milton Arencibia Jan 2022

Scaling Theory Of 3d Magnetic Reconnection X-Line Spreading, Milton Arencibia

Graduate Theses, Dissertations, and Problem Reports

Magnetic reconnection is fundamental process in plasmas that converts magnetic energy into kinetic and thermal energy via a change in magnetic topology. Magnetic reconnection is known to mediate eruptive solar flares, geomagnetic substorms that create the Northern lights, heating and particle acceleration in controlled fusion devices, and is thought to be an important process in numerous settings in high-energy astrophysics. Classical models of reconnection are two-dimensional (2D), but naturally occurring reconnection is three-dimensional (3D), and a manifestation of the 3D nature is that the x-line where the magnetic field topology changes has a finite extent in the direction normal to …


Characterizing The Effects Of Solvent And Analyte Properties On Ionization Efficiency By Novel Field-Free And Field-Enabled Ionization Techniques, Kinkini Udara Jayasundara Jan 2022

Characterizing The Effects Of Solvent And Analyte Properties On Ionization Efficiency By Novel Field-Free And Field-Enabled Ionization Techniques, Kinkini Udara Jayasundara

Graduate Theses, Dissertations, and Problem Reports

In recent years the mass spectrometry (MS) area of field and/or direct analysis has grown dramatically. As a result, field-portable and miniaturized mass spectrometers, introduced only a few years ago, are proliferating. A highly desired feature for field-portable MS, or in-field analysis, is the ability to use ionization techniques requiring very little sample preparation as well as an ability to generate the ions under ambient conditions. Recently, a new ambient ionization technique termed vibrating sharp-edge spray ionization (VSSI) has been introduced which overcomes the field-portable limitations of other spray-based methods including the requirements for auxiliary components (e.g., nebulizing gas and …


Towards A Digital Twin For Characterising Natural Source Zone Depletion: A Feasibility Study Based On The Bemidji Site, Kaveh Sookhak Lari, Greg B. Davis, John L. Rayner Jan 2022

Towards A Digital Twin For Characterising Natural Source Zone Depletion: A Feasibility Study Based On The Bemidji Site, Kaveh Sookhak Lari, Greg B. Davis, John L. Rayner

Research outputs 2022 to 2026

Natural source zone depletion (NSZD) of light non-aqueous phase liquids (LNAPLs) may be a valid long-term management option at petroleum impacted sites. However, its future long-term reliability needs to be established. NSZD includes partitioning, biotic and abiotic degradation of LNAPL components plus multiphase fluid dynamics in the subsurface. Over time, LNAPL components are depleted and those partitioning to various phases change, as do those available for biodegradation. To accommodate these processes and predict trends and NSZD over decades to centuries, for the first time, we incorporated a multi-phase multi-component multi-microbe non-isothermal approach to representatively simulate NSZD at field scale. To …


Black Walnut Plantations In West Virginia: Maximizing Financial Returns Through Decision Modeling And Cash Flow Analysis, Erin Duffy Shaw Jan 2022

Black Walnut Plantations In West Virginia: Maximizing Financial Returns Through Decision Modeling And Cash Flow Analysis, Erin Duffy Shaw

Graduate Theses, Dissertations, and Problem Reports

The purpose of this study was to identify the management strategies that lead to maximum financial returns from a black walnut plantation. To evaluate a selection of plantation establishment scenarios, thinning treatments, and product objectives, an Excel-based black walnut financial model was updated and revised. Key updates to the model included incorporating three cash flows for 1) the collection and wholesale of black walnut sap, 2) producing black walnut syrup, and 3) leasing black walnut trees for tapping. Additionally, outputs from the Forest Vegetation Simulator were integrated into the model’s growth and yield projections as a means of more accurately …


Deep Learning Detection In The Visible And Radio Spectrums, Greg Clancy Murray Jan 2022

Deep Learning Detection In The Visible And Radio Spectrums, Greg Clancy Murray

Graduate Theses, Dissertations, and Problem Reports

Deep learning models with convolutional neural networks are being used to solve some of the most difficult problems in computing today. Complicating factors to the use and development of deep learning models include lack of availability of large volumes of data, lack of problem specific samples, and the lack variations in the specific samples available. The costs to collect this data and to compute the models for the task of detection remains a inhibitory condition for all but the most well funded organizations. This thesis seeks to approach deep learning from a cost reduction and hybrid perspective — incorporating techniques …


From Evaluating The Performance Of Approximations In Density Functional Theory To A Machine Learning Design, Pedram Tavazohi Jan 2022

From Evaluating The Performance Of Approximations In Density Functional Theory To A Machine Learning Design, Pedram Tavazohi

Graduate Theses, Dissertations, and Problem Reports

Density-functional theory (DFT) has gained popularity because of its ability to predict the properties of a large group of materials a priori. Even though DFT is exact, there are inaccuracies introduced into the theory due to the approximations in the exchange-correlation (XC) functionals. Over the 50 years of its existence, scientists have tried to improve the design of the XC functionals. The errors introduced by these functionals are not consistent across all types of solid-state materials. In this project, a high throughput framework was utilized to compare the theoretical DFT predictions with the experimental results available in the Inorganic Crystal …


Efficacy Of Reported Issue Times As A Means For Effort Estimation, Paul Phillip Maclean Jan 2022

Efficacy Of Reported Issue Times As A Means For Effort Estimation, Paul Phillip Maclean

Graduate Theses, Dissertations, and Problem Reports

Software effort is a measure of manpower dedicated to developing and maintaining and software. Effort estimation can help project managers monitor their software, teams, and timelines. Conversely, improper effort estimation can result in budget overruns, delays, lost contracts, and accumulated Technical Debt (TD). Issue Tracking Systems (ITS) have become mainstream project management tools, with over 65,000 companies using Jira alone. ITS are an untapped resource for issue resolution effort research. Related work investigates issue effort for specific issue types, usually Bugs or similar. They model their developer-documented issue resolution times using features from the issues themselves. This thesis explores a …


Inferential Statistics And Information Theoretical Measures: An Approach To Interference Detection In Radio Astronomy, Morgan R. Dameron Jan 2022

Inferential Statistics And Information Theoretical Measures: An Approach To Interference Detection In Radio Astronomy, Morgan R. Dameron

Graduate Theses, Dissertations, and Problem Reports

In a time when technology is rapidly growing, radio observatories are now able to expand their computational power to achieve higher receiver sensitivity power and a more flexible realtime computing approach to probe the universe for its composition and study new astronomical phenomena. This allows searches to go deeper into the universe, and results in the recording of massive quantities of observed data. At the same time, this increases the amount of radio frequency interference (RFI) found in the obtained observatory data. The high power of RFI easily masks the low power of extraterrestrial signals, making them hard to detect …


Development Of Computational Methods For Electronic Structural Characterization Of Strongly Correlated Materials: From Different Ab-Initio Perspectives, Uthpala K. Herath Jan 2022

Development Of Computational Methods For Electronic Structural Characterization Of Strongly Correlated Materials: From Different Ab-Initio Perspectives, Uthpala K. Herath

Graduate Theses, Dissertations, and Problem Reports

The electronic correlations in materials drive a variety of fascinating phenomena from magnetism to metal-to-insulator transitions (MIT), which are due to the coupling between electron spin, charge, ionic displacements, and orbital ordering. Although Density Functional Theory (DFT) successfully describes the electronic structure of weakly interacting material systems, being a static mean-field approach, it fails to predict the properties of Strongly Correlated Materials (SCM) that include transition and rare earth metals where there is a prominent electron localization as in the case of d and f orbitals due to the nature of their spatial confinement.

Dynamical Mean Field Theory (DMFT) is …


Quantifying Water Security In West Virginia And The Potomac River Basin, Eric Carl Edvard Sinius Sjostedt Jan 2022

Quantifying Water Security In West Virginia And The Potomac River Basin, Eric Carl Edvard Sinius Sjostedt

Graduate Theses, Dissertations, and Problem Reports

All healthy ecosystems, communities, and economies are founded on access to clean, adequate water sources to support ecosystem services, provide clean drinking water, and allow the production of water-intensive goods and services. The state of available water resources must be analyzed through the lens of water security, defined as the capability to safeguard sustainable access to adequate quantities of acceptable quality water for people, the economy, and ecosystems. Mountain regions are sources of freshwater resources for downstream regions, which produce disproportionately higher runoff than downstream regions. As a result, mountain regions are often referred to as natural water towers …


The Potential Of Diabase Sills In Eastern Pennsylvania To Store Co2 And H2, Rhiannon R. Schmitt Jan 2022

The Potential Of Diabase Sills In Eastern Pennsylvania To Store Co2 And H2, Rhiannon R. Schmitt

Graduate Theses, Dissertations, and Problem Reports

With anthropogenic CO2 concentrations rising, geologic carbon sequestration and H2 storage are essential processes in mitigating climate change. Typical geologic carbon sequestration involves the capture of anthropogenic CO2 and injection into depleted oil/gas reservoirs or saline formations with an impermeable cap rock to prevent the buoyant migration of CO2. The risk of eventual CO2 migration through these low permeability cap rocks adds expensive monitoring costs to this traditional sequestration strategy. Another method for CO2 sequestration utilizes the reaction of CO2 with mafic and ultramafic rocks. CarbFix, a sequestration project in Iceland, has …


Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom Jan 2022

Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom

Graduate Theses, Dissertations, and Problem Reports

The Long Valley volcanic region, eastern California, USA is most famous for the caldera-forming eruption which produced the Bishop Tuff ~760,000 years ago. Over the last 3,000 years volcanism has been focused in the western margin of the region through punctuated eruptions of silicic lavas and domes. Three simultaneous effusive silicic eruptions, ~600 years ago, generated three lava domes: Obsidian Dome; Glass Creek Dome; and Deadman Dome which erupted onto vastly different topographies. These domes are exceptionally unique as they erupted variable amounts of two textural and chemical endmember lavas (crystal-rich and crystal-poor) that intimately mixed. The overarching goal of …


Studies Of Electromagnetic Counterparts To Gravitational-Wave Sources And The Nonlinear Gravitational-Wave Memory Effect, Ashok Choudhary Jan 2022

Studies Of Electromagnetic Counterparts To Gravitational-Wave Sources And The Nonlinear Gravitational-Wave Memory Effect, Ashok Choudhary

Graduate Theses, Dissertations, and Problem Reports

In this dissertation, theoretical/computational results are presented from the investigations of three different topics within the general research areas of gravitational wave astrophysics and electromagnetic counterparts. First, general relativistic force-free electromagnetic theory and its application to black hole magnetospheres are discussed. In this connection, simulations of a binary black hole merger are examined using the open-source software, GiRaFFE, which is used to model black holes’ magnetospheres and to study supermassive black-hole binary mergers in an external magnetic field. In the simulations, a helical magnetic field structure around each black hole is observed. Electromagnetic energy flux is observed during the inspiral …