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Supersymmetry And The Tunneling Problem In An Asymmetric Double Well, Asim Gangopadhyaya, Prasanta Panigrahi, Uday Sukhatne

Asim Gangopadhyaya

The techniques of supersymmetric quantum mechanics are applied to the calculation of the energy difference between the ground state and the first excited state of an asymmetric double well. This splitting, originating from the tunneling effect, is computed via a systematic, rapidly converging perturbation expansion. Perturbative calculations to any order can be easily carried out using a logarithmic perturbation theory. Our approach yield substantially better results than alternative widely used semiclassical analyses.

Solar Modulation Of The Cosmic Ray Intensity And The Measurement Of The Cerenkov Reemission In Nova’S Liquid Scintillator, Philip James Mason

Doctoral Dissertations

The NOνA (NuMI Off-axis electron neutrino Appearance) experiment is a long baseline neutrino oscillation experiment at Fermi National Accelerator Laboratory. Its purpose is to observe the oscillation of ν_μ (muon neutrino) to ν_e (electron neutrino) and to investigate the neutrino mass hierarchy and CP violation in the neutrino sector. Two detectors have been built for this purpose, a Near Detector 300 feet underground at Fermilab, and a Far Detector, on the surface at Ash River, Minnesota.

The completion of NOνA’s Far Detector in October 2014 enabled not only the recent measurement of neutrino oscillations, but an array of …

Geometry And Thermodynamics Of Filament Bundles, Isaac Bruss

Doctoral Dissertations

In this dissertation I present a study of the geometry and energetics of bundles composed of flexible cohesive filaments. This is a general class of materials, both biological and artificial, existing across many length scales. The aim of this thesis is to investigate the interdependence between the 2D organization of filaments in a bundle’s cross section, and the 3D structure, with an emphasis on the twisting mode of deformation. First we present a model of filament contacts and interactions, which we employ in numerical simulations to study the connection between the ground state energies of constant-pitch bundles and their interior …

Superhalogens Beget Superhalogens: A Case Study Of (Bo2)N Oligomers, Anil K. Kandalam, Boggavarapu Kiran, P. Jena, S. Pietsch, G. Gantefo¨R

Anil K. Kandalam

No abstract provided.

Introduction To Physics, Soumitra Chattopadhyay, Jeffrey Linek

Physics and Astronomy Grants Collections

This Grants Collection for Introduction to Physics was created under a Round Two ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials:

• Linked Syllabus
• Initial Proposal
• Final Report

Effective Microscopic Models For Sympathetic Cooling Of Atomic Gases, Roberto Onofrio, Bala Sundaram

Dartmouth Scholarship

Thermalization of a system in the presence of a heat bath has been the subject of many theoretical investigations especially in the framework of solid-state physics. In this setting, the presence of a large bandwidth for the frequency distribution of the harmonic oscillators schematizing the heat bath is crucial, as emphasized in the Caldeira-Leggett model. By contrast, ultracold gases in atomic traps oscillate at well-defined frequencies and therefore seem to lie outside the Caldeira-Leggett paradigm. We introduce interaction Hamiltonians which allow us to adapt the model to an atomic physics framework. The intrinsic nonlinearity of these models differentiates them from …

Stealth Assessment In Video Games, Val Shute

2009 - 2019 ACER Research Conferences

Games can be powerful vehicles to support learning, but their success in education hinges on getting the assessment part right. In this presentation, I will explore how games can use stealth assessment to measure and support the learning of competencies critical for the future. I will discuss what stealth assessment is, why it is important, and how to develop and accomplish it. I will also provide examples within the context of a game called Physics Playground that I designed and developed with my team. I’ll share what has been learned by recent research on stealth assessments in games, including: Does …

Toward Analog Quantum Computing: Simulating Designer Atomic Systems, Jacob L. Bigelow, Veronica L. Sanford

Physics and Astronomy Summer Fellows

We use a magneto-optical trap to cool rubidium atoms to temperatures in the _µK range. On the _µs timescales of our experiment, the atoms are moving slowly enough that they appear stationary. We then excite them to a Rydberg state, where the outer electron is loosely bound. In these high energy states, the atoms can exchange energy with each other. Since the energy exchange depends on the separation and the relative orientation of the atoms, we can potentially control their interactions by controlling the spatial arrangements of the atoms. We model this system using simulations on a supercomputer …

Models Of Time Travel And Their Consequences, Antonio M. Mantica

Oglethorpe Journal of Undergraduate Research

How do we travel through time? We know that we can move forward in it (we have no choice), but can we jump forward in time? Can we go backward in time? It also gives rise to other troubling questions: is time measurable in distinct increments, or does it flow continuously? In "Models of Time Travel and their Consequences," Antonio Mantica walks the reader through current understandings of how time functions in Einstein's universe and proposes three distinct models to explain it. Following that, he provides a list of experiments to credit or discredit the models. Appropriate for audiences of …

Electron Transmission Through Micrometer Sized Funnelshaped Tapered Glass Capillaries And Electron Micro-Beam Production, Samanthi Jayamini Wickramarachchi

Dissertations

The prime motivation of this work is to understand the fundamental transmission process of an electron beam through a funnel-shaped capillary taking into account its shape together with the energy, angular and time dependence of the transmitted electrons produce a microsized electron beam. The utilized capillaries had inlet/outlet diameters of 800/16 μm, 800/100 μm and lengths of 35 mm. Considerable transmission of 800 and 1000 eV electrons for tilt angles up to 1.5^o and only small transmission for 500 eV electrons was observed for the capillary with the smaller outlet diameter of 16 μm. Incident electrons with energies of …

Integrating Formative Assessment Into Physics Instruction: The Effect Of Formative Vs. Summative Assessment On Student Physics Learning And Attitudes, Chaiphat Plybour

Dissertations

Of many instructional strategies used to improve teaching and learning in science, formative assessment is potentially one of the most effective. A central feature is timely feedback during learning, giving students the opportunity to benefit and improve while also enabling teachers to adjust instruction to learner needs. By contrast, conventional assessment tends to be mostly summative, assigning point scores, grading and ranking students, and providing extrinsic motivation. For maximum effectiveness in enhancing learning, formative assessment should be designed into instruction from the start rather than being an add-on. This project comprised development, teaching, and research aspects. Two physics topic modules, …

Gravitational Wave Background In The Quasi-Steady State Cosmology, Sree Ram Valluri, Sayantan Auddy, J V. Narlikar, S V. Dhurandhar, R G. Vishwakarma

Physics and Astronomy Publications

This paper calculates the expected gravitational wave background (GWB) in the quasi-steady state cosmology (QSSC). The principal sources of gravitational waves in the QSSC are the mini-creation events (MCE). With suitable assumptions the GWB can be computed both numerically and with analytical methods. It is argued that the GWB in QSSC differs from that predicted for the standard cosmology and a future technology of detectors will be able to decide between the two predictions. We also derive a formula for the flux density of a typical extragalactic source of gravitational waves.

Measuring The Hyperfine Splittings Of Lowest Energy Atomic Transitions In Rubidium, Benjamin D. Graber

Undergraduate Honors Thesis Projects

The goal of this experiment was to measure the hyperfine energy splittings of the ground to first excited state transitions in rubidium using saturated absorption spectroscopy. Using this technique, we measured these transition energy spectra by taking the difference of two photodiode outputs due to multiple beams of a single laser scanned over a range of frequencies and shone through a cell of Rb vapor. When the laser frequency was resonant with an atomic transition, photons of those frequencies were absorbed, leaving a dip in intensity of the beam measured at the photodiode. One of the two laser beams had …

Visualizing Relationships Between Related Variables: Improving Physics Education Through D3.Js Network Visualizations, Stephanie Friend

Liberal Arts and Engineering Studies

phiMap is a web application started by Cal Poly professors and students to aid professors in teaching physics. I developed Javascript visualizations for phiMap that serve to simplify the processes of both teaching and learning physics. These visualizations aim to present relationships between physics variables in an easy to understand manner, and they could eventually have a huge impact on physics education.

Dual-Spacecraft Reconstruction Of A Three-Dimensional Magnetic Flux Rope At The Earth's Magnetopause, H. Hasegawa, B. U. Ö. Sonnerup, S. Eriksson, T. K. M. Nakamura

Dartmouth Scholarship

We present the first results of a data analysis method, developed by Sonnerup and Hasegawa (2011), for reconstructing three-dimensional (3-D), magnetohydrostatic structures from data taken as two closely spaced satellites traverse the structures. The method is applied to a magnetic flux transfer event (FTE), which was encountered on 27 June 2007 by at least three (TH-C, TH-D, and TH-E) of the five THEMIS probes near the subsolar magnetopause. The FTE was sandwiched between two oppositely directed reconnection jets under a southward interplanetary magnetic field condition, consistent with its generation by multiple X-line reconnection. The recovered 3-D field indicates that a …

Dr. Hetrick's Last Lecture, James Hetrick

Last Lecture

After finishing his Bachelor's degree in Physics from Case Western Reserve University, Dr. Hetrick spent 13 months at the South Pole Station in Antarctica where he studied cosmic rays, the solar wind, the auroras, and the earth's magnetosphere.

He received his Ph.D. from the University of Minnesota in theoretical particle physics and went on to postdoctoral research positions at ETH in Zürich, the University of Amsterdam, the University of Arizona, and Washington University in St. Louis, before coming to the University of the Pacific in 1997.

At Pacific, Professor Hetrick teaches a variety of classes, including courses like "Cosmology" and …

The Percy Roope Papers, Percy M. Roope

Archives & Special Collections Finding Aids

Percy M. Roope was a Professor of Physics at Clark University from 1921 to 1967. He was a student of Robert H. Goddard and was present at Goddard's first successful launch in 1926. His papers consist of interviews with him concerning Dr. Goddard and correspondence with him.

Towards A Resolution Of The Proton Form Factor Problem: New Electron And Positron Scattering Data, Clas Collaboration, D. Adikaram, L. B. Weinstein, R. P. Bennett, K. P, Adhikari, M. J. Amaryan, S. Careccia, L. El Fassi, C. E. Hyde, A. Klein, S E. Kuhn, M. Mayer, Z. W. Zhao

Physics Faculty Publications

There is a significant discrepancy between the values of the proton electric form factor, G^p_E, extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of G^p_Efrom the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual …

Phys 231: Electric And Electronic Circuits—A Peer Review Of Teaching Project Benchmark Portfolio, Xiaoshan Xu

UNL Faculty Course Portfolios

In this portfolio, I employed a backward design teaching approach on the course PHY231 (Electric and Electronic circuit). I first decide the course objectives and choose the teaching strategies and activities emphasizing student engagement and feedbacks. The effectiveness of the teaching strategies and activities are assessed throughout the course; the adjustments are made accordingly. The results are analyzed at the end of the semester. The assessments indicate that the course objectives are fundamentally achieved and the teaching strategies are effective.

The objectives of the course are:

1. Students will reinforce their understanding in electricity and magnetism.
2. Students will learn theory of …

Assessment Of The Applicability Of Terahertz Spectroscopic Breath Sensing Towards Monitoring Type 1 Diabetic Mellitus, Jessica Rose Thomas

Browse all Theses and Dissertations

Type 1 diabetes is a condition that cumulatively costs around $14.9 billion in medical expenses every year in the United States. Besides being costly, the monitoring of this disease is invasive, painful, and often embarrassing to the afflicted individual; blood and urine testing is currently the daily method of monitoring blood glucose and ketone levels in the body of type 1 diabetics. Though the use of these samples is standard, another avenue for possibly determining blood glucose has not been completely explored. With over 3000 chemicals reportedly found in exhaled human breath, biomarkers associated with this disorder and many of …

Resonant 𝜋⁺𝜸 → 𝜋⁺𝜋⁰ Amplitude From Quantum Chromodynamics, Raúl A. Briceño, Jozef J. Dudek, Robert G. Edwards, Christian J. Shultz, Christopher E. Thomas, David J. Wilson

Physics Faculty Publications

We present the first ab initio calculation of a radiative transition of a hadronic resonance within quantum chromodynamics (QCD). We compute the amplitude for 𝜋𝜋→𝜋𝜸^⋆, as a function of the energy of the 𝜋𝜋 pair and the virtuality of the photon, in the kinematic regime where 𝜋𝜋 couples strongly to the unstable ρ resonance. This exploratory calculation is performed using a lattice discretization of QCD with quark masses corresponding to m_π ≈ 400  MeV. We obtain a description of the energy dependence of the transition amplitude, constrained at 48 kinematic points, that we can analytically continue …

Lectures On Thermodynamics And Statistical Mechanics, V P. Nair

Open Educational Resources

No abstract provided.

Spatiotemporally Periodic Driven System With Long-Range Interactions, Owen Dale Myers

Graduate College Dissertations and Theses

It is well known that some driven systems undergo transitions when a system parameter is changed adiabatically around a critical value. This transition can be the result of a fundamental change in the structure of the phase space, called a bifurcation. Most of these transitions are well classified in the theory of bifurcations. Among the driven systems, spatiotemporally periodic (STP) potentials are noteworthy due to the intimate coupling between their time and spatial components. A paradigmatic example of such a system is the Kapitza pendulum, which is a pendulum with an oscillating suspension point. The Kapitza pendulum has the strange …