Physics Commons^™

Ucna/Ucna+, Robert Pattie

Robert W. Pattie Jr.

The neutron provides a simple yet dynamic nuclear system to study the Standard Model of Particle Physics. The process of transforming a neutron into a proton, an electron, and an anti-neutrino contains a wealth of information in the decay rate and the kinematics of the emitted particles. Precision measurements of angular correlations in neutron β-decay can lend insight to the structure of the weak interaction and probe for physics beyond the Standard Model. The UCNA experiment at the Los Alamos Neutron Science Center is the only experiment to use ultracold neutrons to perform such a measurement, determining the β-asymmetry parameter …

Temperaments And Learning Styles Vs. Academic Performance Of First-Semester Physics Students, Shel Randall

Shel Randall

Comparing Experts And Novices In Solving Electrical Circuit Problems With The Help Of Eye-Tracking, David Rosengrant, Colin Thomson, Taha Mzoughi

David Rosengrant

In order to help introductory physics students understand and learn to solve problems with circuits, we must first understand how they differ from experts. This preliminary study focuses on problem-solving dealing with electrical circuits. We investigate difficulties novices have with circuits and compare their work with those of experts. We incorporate the use of an eye-tracker to investigate any possible differences or similarities on how experts and novices solve electrical circuit problems. Our results show similarities in gaze patterns among all subjects on the components of the circuit. We further found that experts would look back at the circuit while …

Pre-Service Physics Teachers And Physics Education Research, David Rosengrant

David Rosengrant

Training pre-service teachers requires, among other things, content knowledge, pedagogical skills and pedagogical content knowledge. Teacher preparation programs have little, if any spare time to add more courses/activities to their program. However, I argue in this paper that we, as educators, must enhance the amount of physics education research in our pre-service physics teacher training programs. In this study, I analyze the results of two different types of exposure to physics education research (PER) from two different groups of pre-service physics teachers in our masters of arts and teaching program. The preliminary results show, for example that the PER helped …

Vector Acoustic Intensity Around A Tuning Fork, Daniel A. Russell, Justin Junell, Daniel O. Ludwigsen

Daniel Ludwigsen

The acoustic intensity vector field around a tuning fork is investigated. Theory for a longitudinal quadrupole source predicts a well-defined transition between near-field and far-field, with significant circulation of sound energy in the near-field. Vector components of the time-averaged intensity were measured using a two-microphone intensity probe and found to agree well with predictions from theory. The vector intensity map is interpreted, and shown to provide useful information about the near-field of an acoustic source.

A Simple Electric Field Probe In A Gauss's Law Laboratory, Daniel O. Ludwigsen, Gregory N. Hassold

Daniel Ludwigsen

Early in our calculus-based introductory course, students are introduced to electric fields and sometimes struggle with the abstraction of a vector field. They have less familiarity with the phenomena associated with electric fields, and the connection between phenomena and mathematical formalism is weaker. Our very next topic is Gauss's law.

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.

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.

Identification Of Hyperhalogens In Agn(Bo2)M (N = 1–3, M = 1–2) Clusters: Anion Photoelectron Spectroscopy And Density Functional Calculations, Xiang-Yu Kong, Hong-Guang Xu, Pratik Koirala, Wei-Jun Zheng, Anil K. Kandalam, Puru Jena

Anil K. Kandalam

No abstract provided.

Basic Astronomy Labs, Terry L. Smith, Michael D. Reynolds, Jay S. Huebner

Jay S Huebner

Providing the tools and know-how to apply the principles of astronomy first-hand, these 43 laboratory exercises each contain an introduction that clearly shows budding astronomers why the particular topic of that lab is of interest and relevant to astronomy. About one-third of the exercises are devoted solely to observation, and no mathematics is required beyond simple high school algebra and trigonometry.Organizes exercises into six major topics—sky, optics and spectroscopy, celestial mechanics, solar system, stellar properties, and exploration and other topics—providing clear outlines of what is involved in the exercise, its purpose, and what procedures and apparatus are to be used. …

Introduction To Physics Ii: Laboratory Manual, Robert Coakley

Robert Coakley

No abstract provided.

Measurement Of The Half-Life Of The T=1/2 Mirror Decay Of Ne-19 And Its Implication On Physics Beyond The Standard Model, Leah J. Broussard, Henning O. Back, Mitzi S. Boswell, A. S. Crowell, Peter Dendooven, G. S. Giri, Calvin R. Howell, M. F. Kidd, Klaus Jungmann, Wilbert L. Kruithof, A. Mol, Cornelis J. G. Onderwater, Robert W. Pattie Jr., Praveen D. Shidling, M. Sohani, D. J. Van Der Hoek, A. Rogachevskiy, Emil Traykov, Oscar O. Versolato, Lorenz Willmann, Hans W. Wilschut, Andrew T. Young

Robert W. Pattie Jr.

Titanium Oxide Nanotubes: Synthesis, Properties And Applications For Solar Energy Harvesting, Eugen Panaitescu

Eugen Panaitescu

Titanium oxide (titania) nanotubes, although relatively recently discovered (less than 15 years ago), have already shown great promise regarding solar energy harvesting applications, exhibiting very good photocatalytic and photovoltaic properties. An alternative anodization route for production of titania nanotubes at the surface of a titanium foil using chloride ions as catalyst instead of the routinely used highly toxic fluorides, is presented in this work. Moreover, the fabrication parameters are extensively studied, thus providing both an insight into the synthesis mechanism and hints towards possible process optimization routes. Although not forming uniformly over the sample surface and lacking long range ordering, …

Neutron Interferometric Method To Provide Improved Constraints On Non-Newtonian Gravity At The Nanometer Scale, Geoffrey Greene, Vladimir Gudkov

Geoffrey Greene

In recent years, an energetic experimental program has set quite stringent limits on a possible “non-1/r2” dependence on gravity at short length scales. This effort has been largely driven by the predictions of theories based on compactification of extra spatial dimensions. It is characteristic of many such theories that the strength and length scales of such anomalous gravity are not clearly determined from first principles. As a result, it is productive to extend the current limits the range and strength of such hypothetical interactions. As a heavy, neutral, and (almost) stable particle, the neutron provides an ideal probe for the …

Characterizing Scientific Production And Consumption In Physics, Qian Zhang, Nicola Perra, Bruno Gonçalves, Fabio Ciulla, Alessandro Vespignani

Alessandro Vespignani

We analyze the entire publication database of the American Physical Society generating longitudinal (50 years) citation networks geolocalized at the level of single urban areas. We define the knowledge diffusion proxy, and scientific production ranking algorithms to capture the spatiotemporal dynamics of Physics knowledge worldwide. By using the knowledge diffusion proxy we identify the key cities in the production and consumption of knowledge in Physics as a function of time. The results from the scientific production ranking algorithm allow us to characterize the top cities for scholarly research in Physics. Although we focus on a single dataset concerning a specific …

Adaptive Circuits Using Pfet Floating-Gate Devices, Paul Hasler, Bradley Minch, Chris Diorio

Bradley Minch

In this paper, we describe our floating-gate pFET device, with its many circuit applications and supporting experimental measurements. We developed these devices in standard double-poly CMOS technologies by utilizing many effects inherent in these processes. We add floating-gate charge by electron tunneling, and we remove floating-gate charge by hot-electron injection. With this floating-gate technology, we cannot only build analog EEPROMs, we can also implement adaptation and learning when we consider floating-gate devices to be circuit elements with important time-domain dynamics. We start by discussing non-adaptive properties of floating-gate devices and we present two representative non-adaptive applications. First, we discuss using …

Self-Assembly Of Helical Ribbons, Yevgeniya V. Zastavker, Neer Asherie, Aleksey Lomakin, Jayanti Pande, Joanne M. Donovan, Joel M. Schnur, George B. Benedek

Yevgeniya V. Zastavker

The self-assembly of helical ribbons is examined in a variety of multicomponent enantiomerically pure systems that contain a bile salt or a nonionic detergent, a phosphatidylcholine or a fatty acid, and a steroid analog of cholesterol. In almost all systems, two different pitch types of helical ribbons are observed: high pitch, with a pitch angle of 54 ± 2°, and low pitch, with a pitch angle of 11 ± 2°. Although the majority of these helices are right-handed, a small proportion of left-handed helices is observed. Additionally, a third type of helical ribbon, with a pitch angle in the range …

Topics In Electronic Structure And Spectroscopy Of Cuprates, Hsin Lin

Hsin Lin

I have applied first-principles calculations to investigate several interrelated problems concerned with the electronic structure and spectroscopy of cuprates. The specific topics addressed in this thesis are as follows. 1. By properly including doping effects beyond rigid band filling, a longstanding problem of the missing Bi-O pocket in the electronic structure of Bi$_2$Sr$_2$CaCu$_2$O$_{8}$ (Bi2212) is solved. The doping effect is explained in terms of Coulombic effect between layers and is a generic property of all cuprates. 2. A systematic study for Pb/O and rare-earth doping in Bi2212 is carried out to explain the experimental phase diagrams, and a possible new …

Laboratory Manual For Physics, Gary Lewis

Gary C. Lewis

No abstract provided.

Interactive Learningware For Physics Vol. 1: Mechanics, Thermodynamics, Waves, James Tanner, Gary Lewis

Gary C. Lewis

Retaining the comprehensiveness and rigor of the previous edition, this sequel has been dramatically revised to be more student oriented. Definitions and issues have been improved, making them tighter and more easily understood. More than 400 sample problems have been updated and expanded to reinforce physics concepts. Formulas involving elements of calculus are better explained due to additional subsections. A wealth of animated illustrations and full-color photographs will capture today's visually-oriented students' attention.

Interactive Learningware For Physics Vol. 2: Fundamentals Of Physics, James Tanner, Gary Lewis

Gary C. Lewis

Retaining the comprehensiveness and rigor of the previous edition, this sequel has been dramatically revised to be more student oriented. Definitions and issues have been improved, making them tighter and more easily understood. More than 400 sample problems have been updated and expanded to reinforce physics concepts. Formulas involving elements of calculus are better explained due to additional subsections. A wealth of animated illustrations and full-color photographs will capture today's visually-oriented students' attention.

Fall 2010 Sci 2130: Quantum Physics: Information About Course: Learning Objectives, Stephen Holt

Stephen Holt

Modern Physics is based upon a few fundamental ideas that allow the explanation of phenomena that seem to defy consistency with traditional (Newtonian) physics. The most important of these (in the context of engineering applications) are the principles of quantum mechanics and statistical mechanics. This course will introduce the basic concepts of Modern Physics, with particular application to atoms, molecules and the materials utilized in modern electronics.

Fall 2010 Sci 2130: Quantum Physics: Course Materials: Homework Overview, Stephen Holt

Stephen Holt

Modern Physics is based upon a few fundamental ideas that allow the explanation of phenomena that seem to defy consistency with traditional (Newtonian) physics. The most important of these (in the context of engineering applications) are the principles of quantum mechanics and statistical mechanics. This course will introduce the basic concepts of Modern Physics, with particular application to atoms, molecules and the materials utilized in modern electronics.

Fall 2010 Sci 2130: Quantum Physics: Course Materials: Assignments, Stephen Holt

Stephen Holt

Modern Physics is based upon a few fundamental ideas that allow the explanation of phenomena that seem to defy consistency with traditional (Newtonian) physics. The most important of these (in the context of engineering applications) are the principles of quantum mechanics and statistical mechanics. This course will introduce the basic concepts of Modern Physics, with particular application to atoms, molecules and the materials utilized in modern electronics.

Fall 2010 Sci 2130: Quantum Physics: Information About Course: Course Syllabus, Stephen Holt

Stephen Holt

Modern Physics is based upon a few fundamental ideas that allow the explanation of phenomena that seem to defy consistency with traditional (Newtonian) physics. The most important of these (in the context of engineering applications) are the principles of quantum mechanics and statistical mechanics. This course will introduce the basic concepts of Modern Physics, with particular application to atoms, molecules and the materials utilized in modern electronics.

How Deep Is The Irrationalism In The Science?, Pal R. Molnar

Pal R. Molnar

In the last decades a strong skeptic movement started against the para-sciences or irrationalism. We welcome this endeavor and we would like to extend the target of this movement into the field of scientific irrationalism too. In this article we try to discuss some of the clear and evident contradiction in the physics. Most of these problems were published in the last 20 years [1], and here we try to collect the biggest and stunk bugs. With this paper we try to break out the wall of silence about the inner problems of scientific world view. We believe that the …

The End Of 20th Century Physics, Pal R. Molnar

Pal R. Molnar

No abstract provided.

On The Acoustic Of Moving Bodies, Pal R. Molnar

Pal R. Molnar

No abstract provided.

Lattice Thermal Conductivity Of K2(Bi1_Zsbz)8se13 Solid Solutions, Jeffrey S. Dyck, Theodora Kyratsi, Evripides Hatzikraniotis, M Paraskevopoulous, H. K. Shin, Ctirad Uher, Mercouri Kanatzidis

Jeffrey Dyck

The family of solid solutions of the type B -K2(Bi1_zSbz)8Se13 (0

Magnetic And Transport Properties Of The V2– Vi3 Diluted Magnetic Semiconductor Sb2_Xmnxte3, Jeffrey Dyck, P. Svanda, P. Lostak, J. Horak, W. Chen, C. Uher

Jeffrey Dyck

We have measured electrical and magnetic properties of single crystals of Sb2_xMnxTe3 with x =0 – 0.045 at temperatures of 2 K to 300 K. Hall effect measurements indicate that each manganese atom donates approximately one hole to the valence band. The magnetic susceptibility is paramagnetic down to 2 K, and both Curie–Weiss and Brillouin analyses show that manganese substitutes for Sb and takes the Mn2+ state with S=5/2. Contrary to the case of III–V host matrices, manganese does not stimulate ferromagnetic order in the family of bulk layered V2– VI3 diluted magnetic semiconductors, at least in the range of …