Physics Commons™

All Articles in Physics

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Development Of Wearable Sensors For Gait Analysis, 2020 William & Mary

Development Of Wearable Sensors For Gait Analysis, Jorden Smyth

In an ongoing experiment being conducted at The Williamsburg Landing by The Center for Balance and Aging Studies (CBAS), gait analysis is being performed on senior citizens in order to identify gait characteristics that are predictive of an increased likelihood to fall. This thesis describes the design and analysis of wearable sensors meant to assist the Williamsburg Landing study by increasing the efficiency and breadth of data collection. These sensors collect distance data from the foot to the ground over the course of multiple steps and return an approximation of the average step cycle for the subject. From my analysis ...

2020 William & Mary

Studies In Seop Hyperpolarized 3he: Measuring Ko And The Spatial Dependence Of Alkali Polarization, Michael Cairo

3He is an isotope of helium whose nucleus is composed of two protons and one neutron. The proportion of atoms whose spins are pointed along the same direction in a volume of 3He gas is known as the polarization. This study entails two experiments in the field of 3He polarimetry concerned with measuring the polarization of a 3He cell and reducing the uncertainty associated with it. 3He cells are full of gaseous 3He, along with alkali metal vapors, K and Rb in our case. The polarization of a 3He cell can be measured ...

2020 William & Mary

Development And Upgrade Of A Laser Cooling And Trapping System Of Ultracold Potassium Atoms, Bennett Atwater

This thesis describes work to improve the apparatus that cools and loads potassium atoms onto the atom chip. This work consists of two main thrusts: a laser trap translator to help cool and load atoms onto the atom chip and a temperature stabilization system for the lasers that are used to laser cool potassium atoms. The current iteration of the beam translator has the ability to vertically translate a beam ±4.5 mm relative to its incident height. The translator has been shown to not alter the spatial profile of the beam through interference or obstruction. The translator’s rotation ...

2020 Utah State University

Model-Based Properties Of Earth's Protective Shield: Relating Ut-Based Dependencies Of The Open/Closed Boundary, Cutoff Latitude, And L-Shell Parameter With Polar Cap Absorption Events, David A. Smith

High frequency radio continues to be an important communications medium. For example, commercial airlines use high frequency radios as their primary communications mode during transpolar crossings. It has been estimated that over 7000 transpolar flights occur each year. Unfortunately, during geomagnetic storms high frequency communications can become unreliable, especially near Earth's Polar Regions.

Space weather forecasters are burdened with the responsibility of predicting how radio signals might be affected during geomagnetic storms and passing that important information on to commercial airlines, allowing them to adjust flight plans accordingly. Such adjustments can be costly, but are necessary to ensure safety ...

Data Supporting The Paper "The Role Of Turbulent Fluctuations In Aerosol Activation And Cloud Formation", 2020 Michigan Technological University

Data Supporting The Paper "The Role Of Turbulent Fluctuations In Aerosol Activation And Cloud Formation", Prasanth Prabhakaran, Abu Sayeed Md Shawon, Greg Kinney, Subin Thomas, Will Cantrell, Raymond Shaw

Data Files

This data supports the following paper:

Prasanth Prabhakaran, Abu Sayeed Md Shawon, Gregory Kinney, Subin Thomas, Will Cantrell and Raymond A. Shaw, “The role of turbulent fluctuations in aerosol activation and cloud formation”, Proceedings of the National Academy of Sciences (2020), in review.

A Note On The Fine Structure Constant, 2020 University of Nebraska-Lincoln

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

CSE Technical reports

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.

A Note On The Fine Structure Constant, 2020 University of Nebraska-Lincoln

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

Sociology Department, Faculty Publications

We derive the numerical value of the fine structure constant $\alpha$ 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.

A Note On The Fine Structure Constant, 2020 University of Nebraska-Lincoln

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

Sociology Department, 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.

2020 Utah State University

Clustering And Classifying Geophysical Rock Properties Of The San Andreas Fault, Jared Bryan

Physics Capstone Projects

Borehole geophysical data provide important in situ observations for identifying and characterizing geologic and structural features in the subsurface. We perform an unsupervised classification of geophysical logs from the Sand Andreas Fault Observatory at Depth (SAFOD) borehole in order to define intervals of distinct geophysical properties. We focus on borehole geophysical data collected during Phase 3 drilling operations from 3.0-3.3 km measured depth, which encompasses the active trace of the San Andreas Fault. We use dimensionality reduction to increase the interpretability of the retrieved clusters, and we compare the performance of distance- and density-based clustering techniques. K-means clustering ...

2020 Susquehanna University

Mapping And Simulating Standing Wave Patterns In A Microwave Oven, Sana Ahmed

Senior Scholars Day

The goal of our project was to map the standing wave patterns in a microwave oven cavity using experimentation. The next task was then to view the standing wave patterns utilizing computer simulations. In a related project done by one of the group members, a microwave oven was used to find the speed of light. He placed chocolate into the microwave cavity, let the chocolate melt at the antinodes of the standing waves. He then measured the distance between the melted spots, multiplied the distance by the frequency of the microwave and found the speed of light. However, while finding ...

Measurements Of Radio Pulse Reception With Stations Of The Ara Experiment Based On The Spicecore Pulser Data Set, 2020 University of Nebraska - Lincoln

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

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 ...

Optical Relaxation Of Defects In Kapton Caused By Irradiation, 2020 Utah State University

Optical Relaxation Of Defects In Kapton Caused By Irradiation, Ashlan Keeler Swainston

Physics Capstone Projects

Radiation can create atomic-scale defect states in polymers, leading to changes in their optical, electrical and mechanical properties. Recent studies of polymers have shown that these defect states are sensitive to oxygen or air exposure. It is believed that air cause the number of defect states to decrease and the polymers to revert to their original states. However, the time scale of this regression is not known. This experiment quantified the time that it takes one polymer to recover and the extent of said recovery; polymide (PI). In order to study the regression, optical transmission data were taken using a ...

Competing Magnetic Interactions In The Antiferromagnetic Topological Insulator Mnbi2te4, 2020 Iowa State University and Ames Laboratory

Competing Magnetic Interactions In The Antiferromagnetic Topological Insulator Mnbi2te4, Bing Li, J.-Q. Yan, D. Pajerowski, Elijah Gordon, Ana-Marija Nedic, Y. Sizyuk, Liqin Ke, Peter P. Orth, David Vaknin, Robert J. Mcqueeney

Physics and Astronomy Publications

The antiferromagnetic (AFM) compound MnBi2Te4 is suggested to be the first realization of an AFM topological insulator. We report on inelastic neutron scattering studies of the magnetic interactions in MnBi2Te4 that possess ferromagnetic triangular layers with AFM interlayer coupling. The spin waves display a large spin gap and pairwise exchange interactions within the triangular layer are long ranged and frustrated by large next-nearest neighbor AFM exchange. The degree of frustration suggests proximity to a variety of magnetic phases, potentially including skyrmion phases, which could be accessed in chemically tuned compounds or upon the application of symmetry-breaking fields.

The Journey Of A Single Polymer Chain To A Nanopore, 2020 The University of Western Ontario

The Journey Of A Single Polymer Chain To A Nanopore, Navid Afrasiabian

Electronic Thesis and Dissertation Repository

Single chain translocation has been eagerly studied for more than two decades due to its importance in biological processes and also, providing a better understanding of polymer dynamics. Polymer translocation can be divided into three stages of reaching the pore, entering the pore and passing through it. We study the delivery of the chain from the bulk to the entrance, which is called the capture process, for a single chain driven by hydrodynamic flow. Our molecular dynamics-lattice Boltzmann simulations show that the converging flow around the nanopore not only facilitates the process of finding the pore but also deforms the ...

396— Radioactive Decay Calibrations Of Rics Using 41 Ar, 2020 SUNY Geneseo

396— Radioactive Decay Calibrations Of Rics Using 41 Ar, Emily Vanderbilt, Nicole Gindling

GREAT Day

The short-lived isotope-counting system (SLIC) being built for the OMEGA laser facility at LLE requires gaseous radioisotopes for calibration purposes. Using a Plutonium-Beryllium (Pu-Be) source at SUNY Geneseo, 41Ar was made by capturing thermal neutrons via the 40Ar(n,gamma) reaction. Once activated, 41Ar beta decays, producing an electron with endpoint energy of 1.198 MeV. The daughter product is found to be the second excited state of 41K 99.1% of the time. This decays to the ground state and emits a 1.293 MeV gamma ray. To accurately measure the beta activity of 41Ar, the Gamma-X system at ...

2020 SUNY Geneseo

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

GREAT Day

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 ...

240— Target Characterization Using Rutherford Backscattering Spectroscopy, 2020 SUNY Geneseo

240— Target Characterization Using Rutherford Backscattering Spectroscopy, Matthew G. Klein, Anthony C. Cooper, Jovahn A. Roumell

GREAT Day

Rutherford backscattering spectroscopy (RBS) is a non-destructive ion-beam analytical technique that is used to determine properties of a target such as thickness, areal density, and elemental composition. This scattering is the result of Coulomb forces between the target atoms and the incident particle. The energy spectrum of the scattered ions depends on the atomic number of the target atoms as well as the target thickness.

293— Moly - Monitoring Oxygen Levels In Ntof Scintillators Using Cosmic Ray Muons, 2020 SUNY Geneseo

293— Moly - Monitoring Oxygen Levels In Ntof Scintillators Using Cosmic Ray Muons, Sean King, Matthew Signor

GREAT Day

High Energy Density Physics and Inertial Confinement Fusion facilities employ nTOF methods to measure neutron energies. Laser induced fusion facilities use the beam pulse as a start signal and Xylene scintillators as the stop signal to obtain the time of flight. To improve timing performance, the scintillator liquid is quenched with oxygen reducing the light production. However, oxygen reacts with the scintillator liquid causing the detector photo flash decay time to increase that reduces the energy resolution of the detector. An in-situ monitoring system which uses cosmic ray muons to determine the oxygen concentration, is being developed at SUNY Geneseo ...

2020 SUNY Geneseo

297— Modeling Optical Extinction Spectra Of Polystyrene Beads In Water, Justin D'Souza

GREAT Day

To model the global climate, it is critical to understand how light interacts with particles in the atmosphere. Extinction spectra have been measured and simulated for a model system consisting of polystyrene beads in water. These beads have sizes comparable to atmospheric aerosols and can be dyed to mimic the properties of soot. Once the simulation is validated by comparing optimized simulation parameters to nominal particle properties, it can be used to study soot aerosols. We show that our simulation program can return reasonable values for the size and optical properties of this model system.

Volume 12, 2020 Longwood University

Volume 12, Haleigh James, Hannah Meyls, Hope Irvin, Megan E. Hlavaty, Samara L. Gall, Austin J. Funk, Karyn Keane, Sarah Ghali, Antonio Harvey, Andrew Jones, Rachel Hazelwood, Madison Schmitz, Marija Venta, Haley Tebo, Jeremiah Gilmer, Bridget Dunn, Benjamin Sullivan, Mckenzie Johnson

Incite: The Journal of Undergraduate Scholarship

Introduction, Dr. Roger A. Byrne, Dean

From the Editor, Dr. Larissa "Kat" Tracy

From the Designers, Rachel English, Rachel Hanson

Immortality in the Mortal World: Otherworldly Intervention in "Lanval" and "The Wife of Bath's Tale" by Haleigh James

Analysis of Phenolic Compounds in Moroccan Olive Oils by HPLC by Hannah Meyls

Art by Hope Irvin

The Effects of Cell Phone Use on Gameplay Enjoyment and Frustration by Megan E. Hlavaty, Samara L. Gall, and Austin J. Funk

Care, No Matter What: Planned Parenthood's Use of Organizational Rhetoric to Expand its Reputation by Karyn Keane

Analysis of Petroleum Products ...