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Consciousness And Physicalism, Brian Mcgowan Jun 2024

Consciousness And Physicalism, Brian Mcgowan

Dissertations, Theses, and Capstone Projects

Physicalism is a philosophy of mind which attempts to explain consciousness as resulting from physical causes. The lack of a complete and consistent mathematical theory to explain physical causation has led other philosophers of mind to propose that consciousness is a nonphysical essence, property, or substance. However, the idea that physics can be defined atomically and/or deterministically leads to explanatory problems for consciousness, as well as for the dualisms which explain consciousness under these assumptions. This thesis advances a position called “continuous physicalism” which takes all material to result from deformations in the physical medium of space, and any changes …


Time Resolved X-Ray Spectroscopy Of Highly Charged Ar, Nd, And Pr, Timothy Burke May 2024

Time Resolved X-Ray Spectroscopy Of Highly Charged Ar, Nd, And Pr, Timothy Burke

All Dissertations

Highly Charged Ions (HCIs) may be considered ideal mini-laboratory in which one can study the physics of matter and light in an environment of high internal electric field that can not be recreated with standard lab equipment. The remaining electron(s) exist in the extremely large electric field of the nucleus and therefore measurements of electronic transitions in these systems provide stringent tests of our understanding of physics in extreme conditions. Quantum electrodynamics (QED) despite being a powerful theory exhibits large discrepancies for systems under extreme conditions. The work here investigates the atomic properties within non-Maxwellian plasmas. The HCI plasmas studied …


Experimental Analyses Of Emission Lines In The Uv/Vis/Nir Range For Astrophysically-Important Elements: From The Iron Group To R-Process Elements, Brynna Neff May 2024

Experimental Analyses Of Emission Lines In The Uv/Vis/Nir Range For Astrophysically-Important Elements: From The Iron Group To R-Process Elements, Brynna Neff

All Dissertations

Analysis of astrophysical phenomena requires an understanding of the electronic

structure and transition probabilities of the elements present in that environment,

yet there are still many charge states of heavy elements whose electronic

structures and spectroscopic properties are not yet well understood. To address this,

we investigated the spectroscopic properties of three different elements through an

analysis of spectra collected from three different experimental apparatuses.

In order to better understand the spectroscopic properties of Ni I and II, we

analyzed spectra collected from the Compact Toroidal Hybrid (CTH) apparatus at

Auburn University. In this experiment, a nickel sample was inserted …


Boat Wake Attenuation Through Artificial Vegetation - A Case Study From Peche Island, Jamie Kathryn Lilly Jan 2024

Boat Wake Attenuation Through Artificial Vegetation - A Case Study From Peche Island, Jamie Kathryn Lilly

Electronic Theses and Dissertations

The use of nature-based solutions and engineering ideas has sparked interest in the value of vegetated shorelines for protecting against erosion. However, there is a lack of field data, and more research is needed to understand how effective vegetation is in reducing the impact of wind waves and boat wakes. The difference in period between wind waves and boat wakes suggests that they may be attenuated differently, requiring further study to determine the optimal management design. The purpose of this study is to quantify the ability of artificial vegetation to attenuate boat wakes and calculate the drag coefficient for model …


A Multi-Wavelength Determination Of The Total Luminosity And Star Formation Rate Of The Milky Way, Joshua L. Mascoop Jan 2024

A Multi-Wavelength Determination Of The Total Luminosity And Star Formation Rate Of The Milky Way, Joshua L. Mascoop

Graduate Theses, Dissertations, and Problem Reports

The star formation rate (SFR) of the Milky Way is poorly understood in comparison to the SFR of other galaxies. In order to better find the Galaxy's place in the universe, it is imperative to understand the star formation activity occurring within it. We characterize the Galactic \hii\ region luminosity function (LF) at multiple infrared and radio wavelengths using a sample of 797 first Galactic quadrant \hii regions compiled from the WISE Catalog of Galactic \hii Regions. This sample is statistically complete for all regions powered by single stars of type O9.5V and earlier.

We find that neither a single …


Student Performance In Modern Physics In An Active, Partially-Flipped Classroom, Scott Yarbrough Jan 2024

Student Performance In Modern Physics In An Active, Partially-Flipped Classroom, Scott Yarbrough

Physics Dissertations

The effectiveness of the flipped classroom and hybrid-flipped (partially flipped, partially lecture-based) method of instruction has been extensively studied for high school and introductory undergraduate physics courses, and it has been shown to increase student understanding and performance. However, few studies have been done for upper-level undergraduate courses, and even fewer have been done for virtual courses. In Spring 2021 and Fall 2023, a fully virtual, hybrid-flipped Modern Physics course was taught, primarily to a class of primarily juniors and seniors, with some sophomores. All were STEM majors. The same course, with a similar enrolment and demographic of students, was …


An Exploration Of Misconceptions In Introductory Physics, Christopher Mattthew Wheatley Jan 2024

An Exploration Of Misconceptions In Introductory Physics, Christopher Mattthew Wheatley

Graduate Theses, Dissertations, and Problem Reports

The study of student misconceptions about physics concepts has long been an important area of inquiry in physics education research (PER). The research discussed in this dissertation builds upon the developments in PER by exploring the prevalence of consistently held undergraduate student misconceptions in introductory calculus-based physics. This thesis explores the nature of student misconceptions, mistakes, and naive answering patterns in both introductory undergraduate Newtonian mechanics and electromagnetism by applying a network analytic technique called module analysis to student responses to different concept inventories from institutions of various levels of incoming physics preparation. Each study applying these methods also demonstrates …


Thermocatalytic Plasma-Assisted Dry Reforming Of Methane Over Ni/Al2o3 Catalyst, Tyler Wong Dec 2023

Thermocatalytic Plasma-Assisted Dry Reforming Of Methane Over Ni/Al2o3 Catalyst, Tyler Wong

Seton Hall University Dissertations and Theses (ETDs)

Plasma catalysis is an advantageous approach that combines the effects of plasma with the enhancements of a catalyst. By utilizing a nickel catalyst in the plasma discharge zone of a dielectric barrier discharge (DBD), it can give an enhancement to the electrical field, boost microdischarges, and increase conversion and selectivity rates of CH4 and CO2 in the dry reforming of methane (DRM) reaction.

Industrial application of nickel catalysts in DBD Plasma DRM process are limited by poor stability, which is caused by the sintering of active metal particles and coke deposition on the catalyst surface. In this work, …


Temporal And Spectral Analysis Of 1es 2344+514 In Two Flaring States Observed By Veritas, Connor Poggemann Dec 2023

Temporal And Spectral Analysis Of 1es 2344+514 In Two Flaring States Observed By Veritas, Connor Poggemann

Physics

VERITAS observed the bright blazar 1ES 2344+514 during two flaring periods, one from Dec. 17 to Dec. 18, 2015 (MJD 57373-57374) with a peak flux of ~60% of the Crab and another from Nov. 28 to Dec. 3, 2021 (MJD 59546-59551) with a peak flux of ~20% of the Crab. This blazar, located at a redshift of z = 0.044, is classified as an extreme high-frequency-peaked BL Lacertae object (HBL). It is known to be variable, including several previous day-scale flares: Whipple on Dec. 20, 1995, VERITAS on Dec. 7, 2007, and MAGIC on Aug. 11, 2016. The VERITAS near-nightly …


Seabed Reflection Coefficient Variability In The Mono Lake Using Seismic Reflection Sparker Data, Francis Nnamdi Okeifufe Oct 2023

Seabed Reflection Coefficient Variability In The Mono Lake Using Seismic Reflection Sparker Data, Francis Nnamdi Okeifufe

Earth Sciences Theses and Dissertations

Acoustic reflections from a lakebed provide valuable information about the dynamic boundary between water and the lakebed, where sediments and biota in the water column eventually settle. In this study, we present a comprehensive analysis of reflected sound wave amplitudes to gain insights into the physical properties of a water-sediment boundary. We decided to carry out this analysis within the unique ecosystem of the Mono Lake basin due to the fact that the Mono Lake, a meromictic and hypersaline waterbody is situated within one of the most active yet understudied volcanic regions in the United States. The fact that the …


Application Of Overburden Effects To The Elastic Scattering Limit For Cdmslite Run 3, Michael Litke Oct 2023

Application Of Overburden Effects To The Elastic Scattering Limit For Cdmslite Run 3, Michael Litke

Physics Theses and Dissertations

Many different types of astronomical evidence suggest that most of the mass in the universe is attributable to a nonluminous matter, called dark matter by physicists. Dark matter is believed to be one or more new elementary particles with currently unknown properties. So far, the prevailing method for attempting to discern the properties of the new particle(s) is to observe a direct collision between dark matter and standard model particles. SuperCDMS is a direct detection experiment conducted underground that measures ionization and phonon energy in cryogenic germanium crystal detectors. While taking data in the CDMSlite configuration it can amplify the …


Design And Fabrication Of A Trapped Ion Quantum Computing Testbed, Christopher A. Caron Aug 2023

Design And Fabrication Of A Trapped Ion Quantum Computing Testbed, Christopher A. Caron

Masters Theses

Here we present the design, assembly and successful ion trapping of a room-temperature ion trap system with a custom designed and fabricated surface electrode ion trap, which allows for rapid prototyping of novel trap designs such that new chips can be installed and reach UHV in under 2 days. The system has demonstrated success at trapping and maintaining both single ions and cold crystals of ions. We achieve this by fabricating our own custom surface Paul traps in the UMass Amherst cleanroom facilities, which are then argon ion milled, diced, mounted and wire bonded to an interposer which is placed …


Study Of Radiation Effects In Gan-Based Devices, Han Gao Jul 2023

Study Of Radiation Effects In Gan-Based Devices, Han Gao

Electrical Engineering Theses and Dissertations

Radiation tolerance of wide-bandgap Gallium Nitride (GaN) high-electron-mobility transistors (HEMT) has been studied, including X-ray-induced TID effects, heavy-ion-induced single event effects, and neutron-induced single event effects. Threshold voltage shift is observed in X-ray irradiation experiments, which recovers over time, indicating no permanent damage formed inside the device. Heavy-ion radiation effects in GaN HEMTs have been studied as a function of bias voltage, ion LET, radiation flux, and total fluence. A statistically significant amount of heavy-ion-induced gate dielectric degradation was observed, which consisted of hard breakdown and soft breakdown. Specific critical injection level experiments were designed and carried out to explore …


A Study Of Data/Monte Carlo Agreement In Charmed Baryon Decays At Belle Ii, Kaitlyn Thurmond May 2023

A Study Of Data/Monte Carlo Agreement In Charmed Baryon Decays At Belle Ii, Kaitlyn Thurmond

Honors Theses

The Belle II experiment at the SuperKEKB electron-positron accelerator facility in Tsukuba, Japan has a primary goal of searching for new physics beyond the Standard Model of particle physics. Extremely precise measurements of particle decays will be compared with Standard Model predictions in order to expose the presence of new particles and interactions. These measurements are prepared using simulated samples to avoid potential biases when studying the data. The Belle II collaboration produces two types of simulated samples for this purpose. One is produced with consistent calibration payloads and another with payloads calibrated as a function of data taking. This …


Photonic Sensors Based On Integrated Ring Resonators, Jaime Da Silva May 2023

Photonic Sensors Based On Integrated Ring Resonators, Jaime Da Silva

Mechanical Engineering Research Theses and Dissertations

This thesis investigates the application of integrated ring resonators to different sensing applications. The sensors proposed here rely on the principle of optical whispering gallery mode (WGM) resonance shifts of the resonators. Three distinct sensing applications are investigated to demonstrate the concept: a photonic seismometer, an evanescent field sensor, and a zero-drift Doppler velocimeter. These concepts can be helpful in developing lightweight, compact, and highly sensitive sensors. Successful implementation of these sensors could potentially address sensing requirements for both space and Earth-bound applications. The feasibility of this class of sensors is assessed for seismic, proximity, and vibrational measurements.


An Analysis Of Detection Asymmetry Using Baryon Decays In Belle Ii, Matthew Mestayer May 2023

An Analysis Of Detection Asymmetry Using Baryon Decays In Belle Ii, Matthew Mestayer

Honors Theses

The purpose of this study was to determine the detection asymmetry of the Belle II detector using decays of two common baryons, Λ0 → ��π- and Σ+ → ��π0. A Monte Carlo simulation of both decays was used to determine the validity of signal isolation criteria. These criteria were then applied to the Belle II data, allowing for a comparison of the detection asymmetry in the data relative to the simulation. The results show a moderate detection asymmetry when using the Λ0 → ��π- decay, particularly for forward-going baryons. For the Σ+ …


Total Absorption Spectroscopy Of Mo-106 And Tc-106, Michael Cooper May 2023

Total Absorption Spectroscopy Of Mo-106 And Tc-106, Michael Cooper

Doctoral Dissertations

Total absorption spectroscopy is a method of gamma-ray spectroscopy that has gained prominence in the past several decades, as nuclear data revisions are performed on older nuclear data, which is often incomplete. A strong understanding of underlying nuclear data, particularly fission and beta decay data, is essential for nuclear reactors and nuclear fuel decay heat. This PhD work involves the analysis of fission fragments 106Mo [Mo-106] and 106Tc [Tc-106]. These neutron rich isotopes contribute upwards of 6% of the cumulative fission yield of 241Pu [Pu-241] fission, and 4% of 239Pu [Pu-239] fission. Prior data for these two fission fragments only …


Identifying And Analyzing Multi-Star Systems Among Tess Planetary Candidates Using Gaia, Katie E. Bailey May 2023

Identifying And Analyzing Multi-Star Systems Among Tess Planetary Candidates Using Gaia, Katie E. Bailey

Electronic Theses and Dissertations

Exoplanets represent a young, rapidly advancing subfield of astrophysics where much is still unknown. It is therefore important to analyze trends among their parameters to learn more about these systems. More complexity is added to these systems with the presence of additional stellar companions. To study these complex systems, one can employ programming languages such as Python to parse databases such as those constructed by TESS and Gaia to bridge the gap between exoplanets and stellar companions. Data can then be analyzed for trends in these multi-star exoplanet systems and in juxtaposition to their single-star counterparts. This research was able …


Light Scattering From Periodic, Conducting Nanostructures, Wesley Kenneth Mills May 2023

Light Scattering From Periodic, Conducting Nanostructures, Wesley Kenneth Mills

Undergraduate Honors Capstone Projects

A material with broadband light absorbing capabilities has the potential for much usefulness in devices such as photovoltaics and thermoelectrics. By energy conservation, a non-transparent material with low reflectance will be highly absorbing. Thus, much research has been devoted to understanding what makes material having low reflectance across a wide wavelength spectrum.

The importance of a material’s electronic structure in determining reflectance is well-established. Current research is revealing the additional importance of surface architecture in the reflective properties of a material. A metasurface is a two-dimentional material with physical features at or smaller than the wavelength of light considered. These …


Mechanism And Kinetics Of Photocatalytic Partial Oxidation Of Methane On Single Site Mox Reaction Centers., Clint Evrard May 2023

Mechanism And Kinetics Of Photocatalytic Partial Oxidation Of Methane On Single Site Mox Reaction Centers., Clint Evrard

Electronic Theses and Dissertations

Single-site transition-metal doped photocatalysts are a class of materials in which small transition-metal oxide clusters are embedded onto the surface of zeolites, graphene, and bulk semiconductors. Experimental findings demonstrate that VO4, CrO4, NbO4, and WO4 clusters embedded on an MCM- 41 mesoporous amorphous SiO2 are effective photocatalysts for oxidative reactions. The selective direct partial oxidation of methane (POM) to form methanol is essential for efficiently utilizing natural gas. Photocatalytic methane oxidation has advantages over traditional thermal catalysis as it can be deployed at small-scale facilities to reduce methane release into the atmosphere due to flaring potentially. Our work has aimed …


Exploring The Dependence Of Bulges In Spiral Galaxies On Their Environment, William Jackson Clark May 2023

Exploring The Dependence Of Bulges In Spiral Galaxies On Their Environment, William Jackson Clark

Physics Theses & Dissertations

Recent research has shown a relationship between spiral galaxy satellite populations and the size of spiral bulges. The modern cosmological model of our universe (ΛCDM), does not predict this. Instead, ΛCMD predicts that only the total dynamical mass of a host galaxy should be correlated with satellite populations. We investigate this relationship in regimes other than satellites. In this study we compare the bulge to total mass ratios of spiral galaxies to the number of nearby galaxies within “n” Mpc. We use four papers from literature that calculate bulge to total mass ratios of 189 spiral galaxies using …


Empowering Latinos To Pursue A Degree In Astronomy/Physics, Ivon Tapia May 2023

Empowering Latinos To Pursue A Degree In Astronomy/Physics, Ivon Tapia

Capstone Projects and Master's Theses

Empowering Latino students to pursue careers in astronomy/physics is possible if we find the correct way to help them. Astronomy can help our planet, and physics teaches us how to appreciate our earth and everything around us. Currently, Latinos are underrepresented in these careers. This senior capstone examines the different ways that schools could empower Latino students to pursue careers in astronomy/physics. Through the use of literature review, interviews with two teachers and one astronomer, and an anonymous survey of students, the result findings indicate that introducing careers in astronomy/physics to Latino students at a young age could spark their …


Study Of Missing Mass Background In The Clas12 Detector, Jessie Hess, Gerard P. Gilfoyle, Lamya Baashen Apr 2023

Study Of Missing Mass Background In The Clas12 Detector, Jessie Hess, Gerard P. Gilfoyle, Lamya Baashen

Honors Theses

At Jefferson Lab we use the CLAS12 detector to measure the neutron magnetic form factor. An accurate measurement of the CLAS12 neutron detection efficiency (NDE) is required. We use the nuclear reaction ���� → ��′��+�� as a source of tagged neutrons and obtain the NDE from the ratio of expected neutrons to detected ones. We assume the final state consists of ��′��+�� only, use the ��′��+ information to predict the neutron's position(expected) and then search for that neutron(detected). We select neutrons with the missing mass (MM) technique. We use simulation to validate our methods. We simulated events with the Monte-Carlo …


New Physics In The Age Of Precision Cosmology, Vivian I. Sabla Apr 2023

New Physics In The Age Of Precision Cosmology, Vivian I. Sabla

Dartmouth College Ph.D Dissertations

The Lambda-cold dark matter (LCDM) model has become the standard model of cosmology because of its ability to reproduce a vast array of cosmological observations, from the earliest moments of our Universe, to the current period of accelerated expansion, which it does with great accuracy. However, the success of this model only distracts from its inherent flaws and ambiguities. LCDM is purely phenomenological, providing no physical explanation for the nature of dark matter, responsible for the formation and evolution of large-scale structure, and giving an inconclusive explanation for dark energy, which drives the current period of accelerated expansion.

Furthermore, cracks …


Expanding Upon Excitation: The Observance Of Nonlinearity In Alexandrite, Katherine A. Stephens Apr 2023

Expanding Upon Excitation: The Observance Of Nonlinearity In Alexandrite, Katherine A. Stephens

Honors Theses

Nonlinear optical effects are a light-matter interaction that can be observed when multiple optical fields drive a response in the material under excitation. To determine whether or not an effect is present in alexandrite, a beryl stone doped with chromium ions, literature reviews were conducted and research regarding the theory around the nonlinear multiphoton was performed. Safety measures for the laboratory and previous research using the same laser were also examined. This was taken into account when performing original experiments to measure a potential effect from a laser interaction with alexandrite. After an initial experiment was adjusted to filter out …


Certainty Is Wild And Weaving: Analyzing The Clouds Of Venus, Grace Sanger-Johnson Jan 2023

Certainty Is Wild And Weaving: Analyzing The Clouds Of Venus, Grace Sanger-Johnson

Senior Projects Spring 2023

Supposed detection of phosphine as a biosigature in the clouds of Venus has resulted in a flurry of interest in studying the potential habitability of Venus and other Venus-like exoplanets. However, there are still many unanswered questions about the planet's atmosphere. In this senior project, use spectroscopy to better understand the molecular composition and atmospheric dynamics of Venus. To do this, I analyzed partly-processed spectra from a previously unstudied infrared wavelength obtained at NASA’s Infrared Telescope Facility in July 2021. I developed multiple systems of analysis to extract information from the partly processed data and understand the consequences of this …


Symbolic Computation Of Squared Amplitudes In High Energy Physics With Machine Learning, Abdulhakim Alnuqaydan Jan 2023

Symbolic Computation Of Squared Amplitudes In High Energy Physics With Machine Learning, Abdulhakim Alnuqaydan

Theses and Dissertations--Physics and Astronomy

The calculation of particle interaction squared amplitudes is a key step in the calculation of cross sections in high-energy physics. These complex calculations are currently performed using domain-specific symbolic algebra tools, where the computational time escalates rapidly with an increase in the number of loops and final state particles. This dissertation introduces an innovative approach: employing a transformer-based sequence-to-sequence model capable of accurately predicting squared amplitudes of Standard Model processes up to one-loop order when trained on symbolic sequence pairs. The primary objective of this work is to significantly reduce the computational time and, more importantly, develop a model that …


Reflective Freewriting As A Strategy To Improve Pre-Service Teacher’S Physics Content Knowledge And Overall Attitude Toward Physics And Physics Teaching, Kali Ann Shoaf-Laughlin Jan 2023

Reflective Freewriting As A Strategy To Improve Pre-Service Teacher’S Physics Content Knowledge And Overall Attitude Toward Physics And Physics Teaching, Kali Ann Shoaf-Laughlin

MSU Graduate Theses

A pilot study conducted in the pre-service teacher (PST) physics classroom at Missouri State University sought to validate a tool for learning. A writing treatment, in which students were asked to participate in reflective freewriting exercises over the course of the semester was administered to one lab group. The Physics Attitude Scale was used to determine whether a positive impact was made on pre-service teacher attitudes about physics and teaching physics. Classroom exams and lab reports were used to determine whether or not aptitude was affected. This action research study used qualitative data to assess content knowledge and overall shift …


Examining The Relations Among Academic And Non-Cognitive Factors And Student Achievement, Dona Sachini Hasanjalie Hewagallage Jan 2023

Examining The Relations Among Academic And Non-Cognitive Factors And Student Achievement, Dona Sachini Hasanjalie Hewagallage

Graduate Theses, Dissertations, and Problem Reports

Since the 1980s, Physics Education Research (PER) has explored the factors influencing students' success in college. This manuscript reports three different studies to understand the impact of different factors on students' college physics achievement. The first study explored several academic (high school physics preparation, high school preparation, math readiness, and ACT or SAT verbal and mathematics scores) and non-cognitive (self-efficacy, personality, belonging, grade expectation, and demographic) factors using correlation and linear regression analysis to understand their relation to students' physics conceptual understanding measured by the Force and Motion Conceptual Evaluation (FMCE). High school preparation was found to be the most …


Using Machine Learning To Predict Student Outcomes, Saba Fatima Jan 2023

Using Machine Learning To Predict Student Outcomes, Saba Fatima

Graduate Research Theses & Dissertations

Predicting students’ performance to identify which students are at risk of receiving aD/Fail/Withdraw (DFW) grade and ensuring their timely graduation is not just desirable but also necessary in most educational entities. In the US, not only is the Science, Technology, Engineering, and Mathematics (STEM) major becoming less popular among students, the graduation rate of STEM students is steadily declining. The lack of STEM graduates in the US is a serious problem that will place this country at a disadvantage as a competitor in international technological advancement. In order to secure its status as a technological leader internationally, the US institutions …