Other Physics Commons^™

A Note On The Fine Structure Constant, Bilal Khan, Irshadullah Khan

Department of Sociology: Faculty Publications

We derive the numerical value of the fine structure constant in purely number-theoretic terms, under the assumption that in a system of charges between two parallel conducting plates, the Casimir energy and the mutual Coulomb interaction energy agree.

Measurements Of Radio Pulse Reception With Stations Of The Ara Experiment Based On The Spicecore Pulser Data Set, Jesse Osborn, Ilya Kravchenko

UCARE: Research Products

The Askaryan Radio Array Experiment located near the South Pole works to pinpoint specific instances of neutrinos from outside the solar system interacting with nucleons inside the Antarctic ice. Neutrinos are a subatomic particle that has nearly no mass and a net neutral charge. As they are, neutrinos tend not to interact with anything as they travel through space which means they can provide us with information about events occurring far from Earth that might not be easily attained through other methods. Neutrinos are known to be emitted from a myriad of sources, including the Sun, the interaction between cosmic …

285— Modifications Of Cosmic Watch Muon Detectors For Deployment At Letchworth State Park, Kevin Seitz

GREAT Day Posters

For an American Physical Society funded physics outreach project, fifteen Cosmic Watch cosmic ray muon detectors, designed at MIT, are being assembled by students at Geneseo. Over the summer of 2020, ten detectors will be deployed around Letchworth State Park to educate park visitors about cosmic rays. The muon detection rate and cumulative count are displayed on a small OLED screen, with an LED flashing every time a muon passes through the detector’s scintillator. Each incidence is also logged to a micro SD card. Customized open-source software was used to allow the OLED and SD card to work simultaneously. The …

An Analysis Of The Debate Over Creation, Evolution, And The Timeline Of The Universe At An Ecumenical Christian University, Mason Pohlman

Honors Scholars Collaborative Projects

Throughout a significant portion of history and within modern culture, the fields of science and religion appear to be competing for the same holds in a person’s belief system. Universities are where academics and the sciences are the prevailing held truth, while in churches, the Bible reigns as supreme authority. However, in a Christian academic setting, the predominate school of thought in belief systems might turn into a little more of a melting pot. By analyzing gathered personal data (via surveys and interviews), one can begin to piece together the predominate thoughts on the apparent conflict between religion and science …

Magnetic Forces In The Absence Of A Classical Magnetic Field, Ismael L. Paiva, Yakir Aharonov, Jeff Tollaksen, Mordecai Waegell

Mathematics, Physics, and Computer Science Faculty Articles and Research

It is shown that, in some cases, the effect of discrete distributions of flux lines in quantum mechanics can be associated with the effect of continuous distributions of magnetic fields with special symmetries. In particular, flux lines with an arbitrary value of magnetic flux can be used to create energetic barriers, which can be used to confine quantum systems in specially designed configurations. This generalizes a previous work where such energy barriers arose from flux lines with half-integer fluxons. Furthermore, it is shown how the Landau levels can be obtained from a two-dimensional grid of flux lines. These results suggest …

Accurate Tracking Of Position And Dose During Vmat Based On Vmat-Ct, Xiaodong Zhao

LSU Doctoral Dissertations

Purpose: Local tomography reconstruction is achievable with EPID images acquired during VMAT and was named as VMAT-CT. However, it did not gain popularity due to multiple limitations and technical challenges. The goal of this study was to extend VMAT-CT concept, generate complete 3D or 4D CT images and dose, track and adapt VMAT plan based on updated images and dose.

Methods: We considered collimator angle and removed blurred areas in EPID images for VMAT-CT reconstruction to reduce artifacts and improve image quality. VMAT-CT+ images were generated by fusing VMAT-CT and planning CT using rigid or deformable registration. For 4D SBRT …

X-Ray Interferometry Without Analyzer For Breast Ct Application, A Simulation Study, Jingzhu Xu

LSU Doctoral Dissertations

We investigated a novel analyzer-less X-ray interferometer with a spatially modulated phase-grating (MPG) which produces three types of images (attenuation image, phase image and scatter image) for Breast computed tomography (CT). The system provides the three complimentary X-ray images with the goals of limiting the dose to the object and achieving similar attenuation image sensitivity as a standard absorption-only Breast CT. The MPG system features an X-ray source, a source-grating, a single phase-grating, and a detector. No analyzer grating is necessary, compared to other geometries such as Talbot-Lau X-ray interferometry (TLXI). Thus, there is a ~2 times improvement in X-ray …

Evaluation Of Neutron Skyshine Contributions During Injection At An Electron Synchrotron Facility Using Fluka, Andrew D. Hastings

LSU Master's Theses

The Center for Advanced Microstructures and Devices (CAMD) is a 1.5 giga-electron volt (GeV) electron synchrotron research facility under the jurisdiction of Louisiana State University (LSU). When originally constructed in 1992, CAMD was surrounded by pasture and woodland. Over the past several years, urban development of the area has found CAMD bracketed by a shopping center, apartment complex, and business offices. These developments raised concerns amongst the CAMD radiation safety personnel regarding an increased potential for public exposure to radiation. To ensure compliance with the annual public effective dose equivalent limit of 1 milli-sievert (mSv), the radiation monitoring program was …

Characterization Of Magma Storage And Dynamics At Akutan, Semisopochnoi, And Okmok Volcanoes From Analytical And Numerical Models Of Geodetic, Seismic, And Petrologic Data, Kimberly Degrandpre

Earth Sciences Theses and Dissertations

Volcanic eruptions can cause significant socioeconomic loss, but a better understanding of the processes and dynamics influencing the evolution of volcanic plumbing systems will advance the development of eruption forecasting models that will ultimately mitigate hazards and risks associated with eruptive events. Geologic and geophysical data must be integrated in 3D, finite- element, multiphysical, numerical models to define the coupled evolution of magmatic and crustal stress regimes in volcanic environments, but in data limited regions this is not always an option. The remote nature of the Aleutian Island Arc restricts ground-based monitoring and sampling efforts, and due to sparse temporal …

Comprehensive Investigation Of Radiation Techniques For Whole Breast And Post-Mastectomy Irradiations, Yibo Xie

LSU Doctoral Dissertations

Purpose: The purpose of this dissertation is to compare treatment outcomes and cost-effectiveness of various radiotherapy techniques for post-mastectomy radiotherapy (PMRT) and whole breast radiotherapy (WBRT) patients.

Methods: Treatment planning comparison of standard volumetric modulated arc therapy (STD-VMAT), multiple arc VMAT (MA-VMAT), non-coplanar VMAT (NC-VMAT), intensity modulated radiotherapy (IMRT), helical tomotherapy (HT), mixed beam therapy and proton therapy was performed for 9 PMRT patients, and cost-effectiveness of those PMRT techniques compared to standard of care (SOC) were evaluated using a Markov model. Treatment planning comparison of SOC, field-in-field (FIF), hybrid IMRT, full IMRT, STD-VMAT, MA-VMAT and NC-VMAT was performed …

Efficiency And Performance Improvement Via Using Optical Reflectors Of On-Grid Cigs Pv Solar System, Alaa N. Abed, Hazim H. Hussain, Naseer K. Kasim

Karbala International Journal of Modern Science

CIGS PV solar module is a thin film technology (second generation) that is fabricated from Copper-Indium Gallium Selenide. CIGS an abbreviation of Copper-Indium Gallium Selenide. The system, with which reflectors are incorporated, is 5kWp On-Grid CIGS PV Solar system is located at Al Mansour company, Iraq-Baghdad (latitude 33.3°N, longitude 44.4°E and 41m above the sea level). This study improves performance ratio, array efficiency, electrical power and current. All these improvements are done via increasing solar irradiance by using optical reflectors (fabricates from aluminum metal). The maximum values ( at 12:00PM) of the improved and reference …

The Emergence Of The Local Moment Molecular Spin Transistor, Guanhua Hao, Ruihua Cheng, Peter Dowben

Peter Dowben Publications

Local moment molecular systems have now been used as the conduction channel in gated spintronics devices, and some of these three terminal devices might even be considered molecular spin transistors. In these systems, the gate voltage can be used to tune the molecular level alignment, while applied magnetic fields have an influence on the spin state, altering the magnetic properties, and providing insights to the magnetic anisotropy. More recently, the use of molecular spin crossover complexes, as the conduction channel, has led to devices that are both nonvolatile and have functionality at higher temperatures. Indeed, some devices have now been …

Probing Ferroelectricity By X-Ray Absorption Spectroscopy In Molecular Crystals, Fujie Tang, Xuanyuan Jiang, Hsin Yu Ko, Jianhang Xu, Mehmet Topsakal, Guanhua Hao, Alpha T. N'Diaye, Peter Dowben, Deyu Lu, Xiaoshan Xu, Xifan Wu

Peter Dowben Publications

We carry out X-ray absorption spectroscopy experiment at the oxygen K edge in croconic acid (C₅H₂O₅) crystal as a prototype of ferroelectric organic molecular solid, whose electric polarization is generated by proton transfer. The experimental spectrum is well reproduced by the electron-hole excitation theory simulations from configuration generated by ab initio molecular dynamics simulation. When inversion symmetry is broken in the ferroelectric state, the hydrogen bonding environment on the two bonded molecules become inequivalent. Such a difference is sensitively probed by the bound excitation in the pre-edge, which is strongly localized on the excited …

Optimizing Llrf Parameters In The Electron-Ion Collider, William M. Bjorndahl

Physics

To improve particle interaction in the future Electron-Ion Collider (EIC), we investigated different feedback implementations to control the accelerating voltage and examined the power and beam phase for each instance. Using MATLAB, we studied three feedback mechanisms: Direct, One Turn, and Feedforward. Enacting feedforward yielded the best performance. To minimize the klystron power consumption, we analyzed different Low-Level Radio Frequency (LLRF) parameters such as detuning. Combining theory and simulated results, we found the optimal detuning value that minimizes klystron power consumption.

Designing Writing Intensive Upper Division Laboratories In Physics, Sara Callori

Q2S Enhancing Pedagogy

California State University San Bernardino is currently transitioning from quarters to semesters, starting in Fall 2020. As part of this transition, the Department of Physics has transformed its curriculum to better suit the needs of its students. One major facet of this redesign has been the creation of two writing intensive, upper division laboratory courses. From a practical standpoint, under the revamped general education program, we are able to incorporate upper division writing into the major. More importantly, there are many benefits where having a writing-intensive major course aligns with program goals and professional organization recommendations. This includes designing activities …

Homestead National Monument Of America, Acoustic Monitoring Report, 2017, Emma Brown

United States National Park Service: Publications

Executive Summary

This report presents acoustical data gathered by Student Conservation Association interns and the Natural Resource Specialist at Homestead National Monument of America in 2017. Data were collected at one site to provide park managers with information about the acoustical environment, sources of noise, and the existing ambient sound levels within the monument. This deployment also captured acoustic conditions during the total solar eclipse on 8/21/2017. (Results of the eclipse monitoring effort are provided in Appendix B.)

In this deployment, sound pressure level (SPL) was measured continuously every second by a calibrated sound level meter. Other equipment included an …

Homestead National Monument Of America, Acoustic Monitoring, 2011-2012

United States National Park Service: Publications

Executive Summary

This report presents acoustical data gathered by Student Conservation Association interns and the Natural Resource Specialist at Homestead National Monument of America in 2011 and 2012. Data were collected at four sites to provide park managers with information on the acoustical environment, sources of noise, and the existing ambient sound levels within the monument. The data will also inform the park managers with information regarding the potential impact of traffic on Highway 4.

Monitoring occurred at each site during two different seasons (except HOME002) in order to document seasonal variations. In each deployment, sound pressure level (SPL) was …

Overview Of Trends In Indian Optics Research (2008 – 2018), Mallikarjun Kappi, Biradar B S

Library Philosophy and Practice (e-journal)

The present study deals with the assessment of Indian optics research output as reflected in Web of Science (WOS) database for the period 2008 to 2018 for identifying the research output in the field of optics literature. It also provides a comparative evaluation and performance of different types of scientometric indicators, such as number of publications, number of citations and collaboration from India. The Indian optics research has increased exponentially over the last decade.

Density Functional Theory Study Of Two-Dimensional Boron Nitride Films, Pradip R. Niraula

Dissertations, Theses, and Capstone Projects

Since graphene was isolated in 2004, the number of two-dimensional (2D) materials and their scientific relevance have grown exponentially. Besides graphene, one of the most important and technolocially promizing 2D materials that has emerged in recent years is hexagonal boron nitride, in its monolayer or multilayer form. In my thesis work, I used density functional theory (DFT) calculations to investigate the properties of boron nitride films. In particular, I first studied the properties (i.e. formation energy, defect states, and structure) of point charged defects in monolayer and bilayer hexagonal boron nitride, and subsequently, I focused on the linear and nonlinear …

Itinerant Ferromagnetism And Intrinsic Anomalous Hall Effect In Amorphous Iron-Germanium, D. S. Bouma, Z. Chen, B. Zhang, F. Bruni, M. E. Flatté, A. Ceballos, R. Streubel, L. W. Wang, R. Q. Wu, F. Hellman

Robert Streubel Papers

The amorphous iron-germanium system (a-Fe_xGe_1-x) lacks long-range structural order and hence lacks a meaningful Brillouin zone. The magnetization of a-Fe_xGe_1-x is well explained by the Stoner model for Fe concentrations x above the onset of magnetic order around x=0.4, indicating that the local order of the amorphous structure preserves the spin-split density of states of the Fe-3d states sufficiently to polarize the electronic structure despite k being a bad quantum number. Measurements reveal an enhanced anomalous Hall resistivity ρ_xy^AH relative to crystalline FeGe; this ρ_xy^AH is compared to density-functional …