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1

Atomic Physics  

NSDL National Science Digital Library

This collection provides a basic introduction to Atomic Physics. It reviews the building blocks of atomic structure, explores atomic isotopes, explains Einstein's famous equation E = mc2, and introduces the various types of radiation.

Christopher Griffith

2

Extending synchrotron-based atomic physics experiments into the hard X-ray region  

SciTech Connect

The high-brightness, hard x-ray beams available from third-generation synchrotron sources are opening new opportunities to study the deepest inner shells of atoms, an area where little work has been done and phenomena not observed in less tightly bound inner-shells are manifested. In addition scattering processes which are weak at lower energies become important, providing another tool to investigate atomic structure as well as an opportunity to study photon/atom interactions beyond photoabsorption. In this contribution the authors discuss some of the issues related to extending synchrotron-based atomic physics experiments into the hard x-ray region from the physical and the experimental point of view. They close with a discussion of a technique, resonant Raman scattering, that may prove invaluable in determining the spectra of the very highly-excited states resulting from the excitation of deep inner shells.

LeBrun, T. [Argonne National Lab., IL (United States). Physics Div.

1996-12-31

3

Atomic Physics 16: Sixteenth International Conference on Atomic Physics. Proceedings  

SciTech Connect

These proceedings represent papers presented at the 16th International Conference on Atomic Physics held in Windsor, Ontario, Canada, in August, 1998. The topics discussed included a wide array of subjects in atomic physics such as atom holography, alignment in atomic collisions, coulomb{minus}interacting particles, muon experiments, x{minus}rays from comets, atomic electron collisions in intense laser fields, spectroscopy of trapped ions, and Bose{minus}Einstein condensates. This conference represents the single most important meeting world wide on fundamental advances in atomic physics. There were 30 papers presented at the conference,out of which 4 have been abstracted for the Energy, Science and Technology database.(AIP)

Baylis, W.E.; Drake, G.W. [Department of Physics, University of Windsor, Windsor, Ontario, N9B 3P4 (CANADA)

1999-06-01

4

Atomic and Relativistic Physics  

Microsoft Academic Search

Course Description: This course is a basic study of modern physics in the areas of 7. relativity and quantum mechanics as applied to a wide range of phenomena. The fundamental ideas of atomic structure and quantization will be explored within the context of isolated systems; these ideas include Dalton's Law, Boyle's Law, Newton's Laws, Heisenberg's Uncertainty Principle, de Broglie Waves,

Keith Andrew; R. P. Feynman

5

Experiments with Stored Ions at the Boarder Line Between Atomic = and Nuclear Physics  

NASA Astrophysics Data System (ADS)

Particles stored in ion traps or storage rings open up the possibility to study the properties of rare species with high accuracy. The talk will concentrate on recent high-precision experiments performed at the heavy-ion accelerator GSI/Darmstadt, the on-line isotope separator ISOLDE, CERN/Geneva and at the Manne-Siegbahn Laboratory in Stockholm. These are measurements of the hyperfine structure in the ground state of hydrogen-like heavy ions by laser spectroscopy, x-ray spectroscopy of the 1s-Lamb shift of hydrogen-like gold and uranium ions, the observation of the bound-state beta decay and mass measurements of radioactive isotopes in storage rings and ion traps.

Kluge, H.-Juergen

1997-04-01

6

Contemporary Aspects of Atomic Physics  

ERIC Educational Resources Information Center

The approach generally used in writing undergraduate textbooks on Atomic and Nuclear Physics presents this branch as historical in nature. Describes the concepts of astrophysics, plasma physics and spectroscopy as contemporary and intriguing for modern scientists. (PS)

Knott, R. G. A.

1972-01-01

7

Informational experiments with microparticles and atoms  

E-print Network

Accepting information as a physical category and ascribing to inanimate matter some spirit (consciousness, intelligence) allows to explain quantum-mechanical phenomena, including delayed-choice and EPR-Bohm-Bell experiments, as well as irreversibility of time, remaining on the basis of local realism, and suggest essentially new experiments with microparticles and atoms in which information plays the principal role.

Raoul Nakhmanson

2005-09-07

8

TOPICS IN ATOMIC PHYSICS C. E. Burkhardt  

E-print Network

........................................................................................................................... 1 1.2 The Bohr model of the atomTOPICS IN ATOMIC PHYSICS C. E. Burkhardt Department of Physics St. Louis Community College St .................................................................. 9 1.4 Atomic dimensions ­ is a0 a reasonable atomic diameter

Leventhal, Jacob J.

9

The Tokamak Physics Experiment  

NASA Astrophysics Data System (ADS)

The mission of the Tokamak Physics Experiment (TPX) [Nevins et al., Plasma Physics and Controlled Nuclear Fusion, Würzburg (International Atomic Energy Agency, Vienna, 1992), Vol. 3, p. 279] is to develop the scientific basis for an economically competitive and continuously operating tokamak fusion power source. This complements the primary mission of the International Thermonuclear Experimental Reactor (ITER) [ITER Document Ser. No. 18 (International Atomic Energy Agency, Vienna, 1991)], the demonstration of ignition and long-pulse burn, and the integration of nuclear technologies. The TPX program is focused on making the demonstration power plant that follows ITER as compact and attractive as possible, and on permitting ITER to achieve its ultimate goal of steady-state operation. This mission of TPX requires the development of steady-state regimes with high beta, good confinement, and a high fraction of a self-driven bootstrap current. These regimes must be compatible with plasma stability, strong heat-flux dispersion in the divertor region, and effective particle control.

Davidson, Ronald C.; Goldston, Robert J.; Neilson, George H.; Thomassen, Keith I.

1995-06-01

10

Probing the Planck Scale in Low-Energy Atomic Physics  

NASA Astrophysics Data System (ADS)

Experiments in atomic physics have exceptional sensitivity to small shifts in energy in an atom, ion, or bound particle. They are particularly well suited to search for unique low-energy signatures of new physics, including effects that could originate from the Planck scale. A number of recent experiments have used CPT and Lorentz violation as a candidate signal of new physics originating from the Planck scale. A discussion of these experiments and their theoretical implications is presented.

Bluhm, R.

2002-02-01

11

Experiments in Ice Physics.  

ERIC Educational Resources Information Center

Describes experiments in ice physics that demonstrate the behavior and properties of ice. Show that ice behaves as an ionic conductor in which charge is transferred by the movement of protons, its electrical conductivity is highly temperature-dependent, and its dielectric properties show dramatic variation in the kilohertz range. (Author/GA)

Martin, P. F.; And Others

1978-01-01

12

Plasma Effects in Cold Atom Physics  

NASA Astrophysics Data System (ADS)

We discuss collective effects that can be relevant in cold atom physics. Similarities with plasma physics are emphasized. Both neutral and ionized atomic clouds are considered. We establish the basic frequencies and wave modes of a cloud of ultra-cold neutral atoms confined in a magneto-optical trap. The existence of a hybrid mode, Tonks-Dattner resonances and Mie oscillations are studied. Landau damping and resonant neutral atom-density wave interactions are also considered. Finally, free expansion and ambipolar diffusion regimes for a cold ionized cloud of atoms are discussed.

Mendonça, J. T.; Loureiro, J.; Terças, H.; Kaiser, R.

2008-03-01

13

Relativistic atomic physics at the SSC  

SciTech Connect

This report discusses the following proposed work for relativistic atomic physics at the Superconducting Super Collider: Beam diagnostics; atomic physics research; staffing; education; budget information; statement concerning matching funds; description and justification of major items of equipment; statement of current and pending support; and assurance of compliance.

NONE

1990-12-31

14

Atomic physics with vapor-cell clocks  

NASA Astrophysics Data System (ADS)

The most widely used atomic frequency standards (or clocks) are based on the microwave resonant frequencies of optically pumped vapors of alkali-metal atoms in glass cells filled with buffer gas. These vapor-cell clocks are secondary, not primary frequency standards mainly because of the light and pressure shifts, which alter the resonant frequencies of the alkali-metal atoms. This dissertation presents studies of atomic physics important to vapor-cell clocks and, in particular, their accuracy. First, we report a simple method to suppress the light shift in optical pumping systems. This method uses only frequency modulation of a radio frequency or microwave source, which excites an atomic resonance, to simultaneously lock the source frequency to the atomic resonance and lock the pumping light frequency to suppress the light shift. This technique can be applied to many optical pumping systems that experience light shifts. It is especially useful for atomic clocks because it improves the long-term performance, reduces the influence of a pumping laser, and requires less equipment than previous methods. Next, we present three studies of the pressure shift, starting with an estimation of the hyperfine-shift potential that is responsible for most of the pressure shift. We then show that the microwave resonant frequencies of ground-state Rb and Cs atoms in Xe buffer gas have a relatively large nonlinear dependence on the Xe pressure, presumably because of short-lived RbXe and CsXe van der Waals molecules. The Xe data show striking discrepancies with the previous theory for nonlinear shifts, most of which is eliminated by accounting for the spin-rotation interaction in addition to the hyperfine-shift interaction in the molecules. To the limit of our experimental accuracy, the shifts of Rb and Cs in He, Ne, and N2 were linear with pressure. We then consider the prospects for suppressing the pressure shift with buffer-gas mixtures and feedback. Finally, we report an investigation of the potential for integrating spheres to enhance absorption in optically thin alkali-metal vapor cells. We demonstrate a roughly ten-fold increase of the optical absorption that seems to be limited by the glass cell required to contain the alkali-metal vapor.

McGuyer, Bart Hunter

15

B Physics (Experiment)  

E-print Network

In past few years the flavor physics made important transition from the work on confirmation the standard model of particle physics to the phase of search for effects of a new physics beyond standard model. In this paper we review current state of the physics of b-hadrons with emphasis on results with a sensitivity to new physics.

Michal Kreps

2010-08-13

16

Atomic and Nuclear Physics with Radioactive Isotopes  

NASA Astrophysics Data System (ADS)

Capabilities in laser cooling and trapping, isotope production and nuclear chemistry enable us to pursue a variety of far-reaching experiments at the interface of atomic and nuclear physics with radioactive isotopes. Here we highlight both recent precision polarization measurements of Rb isotopes in an optical dipole trap for a new-generation ?-asymmetry measurement and our progress on characterizing the ^229Th nuclear isomer. Optical pumping allows us to prepare a dipole-trapped Rb atom sample with an initial polarization of 0.972(2), measured using resolved microwave transitions. The spin polarization further purifies to 0.987(1) in 10 seconds and remains above 0.99 when the two-body collision loss rate between atoms in mixed spin states is greater than the one-body trap loss rate [1]. We also describe our progress toward directly characterizing the ^229Th nuclear isomer transition and discuss our results in comparison to other published measurements. The isomer transition in ^229Th (indirectly-measured transition wavelength near 160 nm [2]) promises to be the first nuclear transition excitable with coherent laser sources. Its estimated narrow linewidth (natural lifetime ? ˜ 7 hr.) and wavelength make it a prime candidate to use for a nuclear clock and applicable in fields such as cosmology and metrology. [1] PRA 83, 013416 (2011). [2] PRL 98, 142501 (2007).

Natali Martinez de Escobar, Y.; Bond, E.; Moody, A.; Rundberg, R.; Torgerson, J.; Vieira, D. J.; Zhao, X.

2011-06-01

17

Physics in Action: Seeing Atoms  

NSDL National Science Digital Library

This article describes how scanning probe microscopes can be used to see atoms, which are too small to see with optical instruments. These instruments can be used for a wide range of both imaging and control of atoms. The site contains diagrams, pictures, and links to research in this field.

Central, Physics

2004-04-06

18

Quantum physics: An atomic SQUID  

NASA Astrophysics Data System (ADS)

Superconducting quantum circuits are the core technology behind the most sensitive magnetometers. An analogous device has now been implemented using a gas of ultracold atoms, with possible applications for rotation sensing.

Sackett, Charles A.

2014-01-01

19

Quantum Physics of Atoms and Materials  

E-print Network

. Niels Bohr (1913) Physicists Dawn Meekhof and Steve Jefferts with their atomic clock, which would. Copyright Geoffrey Wheeler, 1999.) Niels Bohr, Danish physicist who in 1913 discovered the quantum model299 9 Quantum Physics of Atoms and Materials The first postulate enunciates the existence

Moeck, Peter

20

Bringing atoms into first-year physics  

NSDL National Science Digital Library

We argue that thermal physics should not be treated as a separate topic in introductory physics. The first-year calculus-based college physics should offer a modern, unified view of physics representative of the contemporary scientific enterprise. It should focus on the consequences of the central fact that matter is composed of atoms, and on the process of modeling physical systems. Such a focus is more interesting and relevant to students than a repetition of a purely classical treatment. We give an example of a course that emphasizes physical modeling of phenomena in terms of the atomic nature of matter. Thermal physics is woven into the entire course and is fully integrated with classical and semiclassical mechanics.

Chabay, Ruth; Sherwood, Bruce

2005-10-11

21

Atomic Physics, Science (Experimental): 5318.42.  

ERIC Educational Resources Information Center

Presented is the study of modern and classical concepts of the atom; the structure of the atom as a mass-energy relationship; practical uses of radioactivity; isotopes; and the strange particles. Performance objectives (16) are included as well as a detailed course outline. Experiments, demonstrations, projects and reports to enhance student…

Petit, Ralph E.

22

Physically Sound Orthogonality Procedures for Atomic Physics Calculations  

Microsoft Academic Search

A physically sensible orthogonality procedure for use in atomic calculations is described. For clarity we focus on the orthogonalization of ejected-election orbitals to bound target orbitals for calculation of single ionization of multielectron atoms. A simple application to electron ionization of helium is given to illustrate the general analytic properties of the procedure and its practicability.

Alvin M. Halpern; Brian K. Thomas

1979-01-01

23

Study of atomic physics and population inversions with plasma focus  

SciTech Connect

The plasma focus can be used to generate high temperature and high density plasmas. Neon-like plasmas have previously been studied in Z-pinches and laser produced plasmas as sources for XUV and x-ray lasers. The plasma focus provides a simple and inexpensive source for studying atomic physics of highly ionized atoms. A detailed understanding of atomic physics at high temperatures, densities, and megagauss magnetic fields is necessary for possible x-ray laser designs. Methods that are generally used for obtaining population inversions include collisional ionization of the inner shells of multi-electron atoms and ions, photoexcitation, and electron collisional excitation of ions, collisional combination of ions, and atom-ion resonant charge exchange. We will discuss some possible experiments to help understand the atomic physics under the above condition. Some ideas and calculations will be given to show the feasibility of doing atomic physics relating to x-ray lasers with a plasma focus. 13 refs., 2 figs.

Oona, H.; Hodgdon, M.L.; Rickel, D.G.; Freeman, B.L.

1989-01-01

24

VOLUME 6S, NUMBER 13 PHYSICAL REVIEW LETTERS Very Cold Trapped Atoms in a Vapor Cell  

E-print Network

VOLUME 6S, NUMBER 13 PHYSICAL REVIEW LETTERS Very Cold Trapped Atoms in a Vapor Cell 24 SEPTEMBER sample of spin-polarized trapped atoms. The technique used dramati- cally simplifies the production of laser-cooled atoms. In this experiment, 1.8x10' neutral cesium atoms were optically captured directly

Monroe, Christopher

25

Planning a School Physics Experiment.  

ERIC Educational Resources Information Center

Presents a model for planning the measurement of physical quantities. Provides two examples of optimizing the conditions of indirect measurement for laboratory experiments which involve measurements of acceleration due to gravity and of viscosity by means of Stokes' formula. (ML)

Blasiak, Wladyslaw

1986-01-01

26

Future directions in kaonic atom physics  

E-print Network

Recent progress and open problems in kaonic atom physics are presented. A connection between phenomenological deep potentials and the underlying $K^-N$ interaction is established as well as the need for a theory for multinucleon absorption of kaons. $K^-$ absorption at rest to specific $\\Lambda $ hypernuclei states is briefly discussed.

E. Friedman

2011-11-30

27

Practical Physics: A Model of Vibrating Atoms in a Solid  

NSDL National Science Digital Library

In this classroom activity, learners construct a wobbly model of a crystal array to investigate the attractive interaction between neighboring atoms in a solid. By using this less traditional model, students explore chemical bonds as analogous to a stretched or compressed spring. Gently shaking the model shows how stored energy can be communicated to the next layer of atoms. Vigorous shaking causes the model to break apart, representing the breaking of chemical bonds. See Related Materials for a link to a Flash animation that helps learners visualize the atomic structure of metals and how the chemical bonds are impacted by bending and heating. This item is part of a much larger collection of physics/astronomy experiments, sponsored by the UK's Institute of Physics and funded by the Nuffield Curriculum Centre.

Centre, Nuffield C.

2011-08-16

28

Materials International Space Station Experiment-6 (MISSE-6) Atomic Oxygen Fluence Monitor Experiment  

NASA Technical Reports Server (NTRS)

An atomic oxygen fluence monitor was flown as part of the Materials International Space Station Experiment-6 (MISSE-6). The monitor was designed to measure the accumulation of atomic oxygen fluence with time as it impinged upon the ram surface of the MISSE 6B Passive Experiment Container (PEC). This was an active experiment for which data was to be stored on a battery-powered data logger for post-flight retrieval and analysis. The atomic oxygen fluence measurement was accomplished by allowing atomic oxygen to erode two opposing wedges of pyrolytic graphite that partially covered a photodiode. As the wedges of pyrolytic graphite erode, the area of the photodiode that is illuminated by the Sun increases. The short circuit current, which is proportional to the area of illumination, was to be measured and recorded as a function of time. The short circuit current from a different photodiode, which was oriented in the same direction and had an unobstructed view of the Sun, was also to be recorded as a reference current. The ratio of the two separate recorded currents should bear a linear relationship with the accumulated atomic oxygen fluence and be independent of the intensity of solar illumination. Ground hyperthermal atomic oxygen exposure facilities were used to evaluate the linearity of the ratio of short circuit current to the atomic oxygen fluence. In flight, the current measurement circuitry failed to operate properly, thus the overall atomic oxygen mission fluence could only be estimated based on the physical erosion of the pyrolytic graphite wedges. The atomic oxygen fluence was calculated based on the knowledge of the space atomic oxygen erosion yield of pyrolytic graphite measured from samples on the MISSE 2. The atomic oxygen fluence monitor, the expected result and comparison of mission atomic oxygen fluence based on the erosion of the pyrolytic graphite and Kapton H atomic oxygen fluence witness samples are presented in this paper.

Banks, Bruce A.; Miller, Sharon K.; Waters, Deborah L.

2010-01-01

29

Handbook explaining the fundamentals of nuclear and atomic physics  

NASA Technical Reports Server (NTRS)

Indoctrination document presents nuclear, reactor, and atomic physics in an easy, straightforward manner. The entire subject of nuclear physics including atomic structure ionization, isotopes, radioactivity, and reactor dynamics is discussed.

Hanlen, D. F.; Morse, W. J.

1969-01-01

30

8.422 Atomic and Optical Physics II, Spring 2005  

E-print Network

This is the second of a two-semester subject sequence beginning with Atomic and Optical Physics I (8.421) that provides the foundations for contemporary research in selected areas of atomic and optical physics. Topics ...

Chuang, Isaac

31

Progress of Atomic and Molecular Physics for Chinese Scientific Data Community  

NASA Astrophysics Data System (ADS)

We will report some progress of Atomic and Molecular Physics in China, especially for national needs such as astrophysics, energy, environment and medical physics research programs etc.. Various theoretical activities and experimental activities have been initiated by Chinese Research Association of Atomic and Molecular Data. For example, in order to manage huge sets of energy levels for atoms (atomic ions) required in our national energy and astrophysical research programs, we focus a manageable set of physical parameters in multichannel quantum defect theory (MQDT) based on which the huge atomic energy levels can be reproduced without missing any one. We also elucidate the physical meanings of such MQDT physical parameters which are related to scattering matrices of electron-ion collisions. Huge sets of collision data can also be managed. The scenario can also be extended to molecular data required in our national environmental research programs. In order to provide benchmark examinations of atomic and molecular data, we also report some progresses of atomic and molecular experimental measurements such as electron scattering experiments, storage ring experiments, laser spectroscopy and molecular beam experiments etc.. In order to pursue precise measurements in physics, there are also some attempts to set up atomic experiments by laser cooling techniques. Some atomic interference experiments are also reported.

Li, Jia-Ming; Han, Xiao-Ying

2009-05-01

32

PhD STUDENT IN ATOMIC THEORY The Theory group in the Atomic Physics division, Department of Physics, Stockholm  

E-print Network

Negative Ions and Photodetachment Relativistic Many-Body theory of atomic structure Highly Charged IonsPhD STUDENT IN ATOMIC THEORY The Theory group in the Atomic Physics division, Department of Physics ­ Resonances- in Atoms and Ions Recombination processes in electron-ion collisions - Dielectronic Recombination

Lindroth, Eva

33

Interactive Plasma Physics Education Experience  

NSDL National Science Digital Library

IPPEX (Internet Plasma Physics Education Experience) is a project developed to allow students and teachers to participate remotely in scientific research at the nation's largest fusion energy laboratory. It offers an introduction to the study of controlled fusion using the tokamak reactor, a fusion confinement device located at Princeton University. The web site includes simulations of plasma reactions and an interactive tutorial on the process of fusion, its potential as a sustainable energy source, and the challenges of harnessing its power. The data analysis exercises are appropriate for introductory physics learners.

Laboratory, Princeton P.

2003-10-10

34

Atomic, molecular, and optical physics with X-rays  

NASA Astrophysics Data System (ADS)

With the advent of third-generation synchrotron-radiation sources now being built, research in the area of atomic, molecular, and optical physics using X-rays from these insertion-device-based facilities is expected to experience a renaissance. Many of the most sought after experimental goals in this area of reseach will become possible or even routine. To highlight some of the exciting possibilities, some specific examples are discussed, such as the X-ray and Auger resonant-Raman effect and polarized molecular X-ray emission. Plans for implementation of an X-ray synchrotron-radiation beamline dedicated to atomic, molecular, and optical physics at the Advanced Light Source are presented, with emphasis on the enhanced capabilities that will be available at this state-of-the-art facility.

Lindle, Dennis W.; Crasemann, Bernd

1991-05-01

35

Solid Hydrogen Experiments for Atomic Propellants  

NASA Technical Reports Server (NTRS)

This paper illustrates experiments that were conducted on the formation of solid hydrogen particles in liquid helium. Solid particles of hydrogen were frozen in liquid helium, and observed with a video camera. The solid hydrogen particle sizes, their molecular structure transitions, and their agglomeration times were estimated. article sizes of 1.8 to 4.6 mm (0.07 to 0. 18 in.) were measured. The particle agglomeration times were 0.5 to 11 min, depending on the loading of particles in the dewar. These experiments are the first step toward visually characterizing these particles, and allow designers to understand what issues must be addressed in atomic propellant feed system designs for future aerospace vehicles.

Palaszewski, Bryan

2001-01-01

36

Physically representative atomistic modeling of atomic-scale friction  

NASA Astrophysics Data System (ADS)

Nanotribology is a research field to study friction, adhesion, wear and lubrication occurred between two sliding interfaces at nano scale. This study is motivated by the demanding need of miniaturization mechanical components in Micro Electro Mechanical Systems (MEMS), improvement of durability in magnetic storage system, and other industrial applications. Overcoming tribological failure and finding ways to control friction at small scale have become keys to commercialize MEMS with sliding components as well as to stimulate the technological innovation associated with the development of MEMS. In addition to the industrial applications, such research is also scientifically fascinating because it opens a door to understand macroscopic friction from the most bottom atomic level, and therefore serves as a bridge between science and engineering. This thesis focuses on solid/solid atomic friction and its associated energy dissipation through theoretical analysis, atomistic simulation, transition state theory, and close collaboration with experimentalists. Reduced-order models have many advantages for its simplification and capacity to simulating long-time event. We will apply Prandtl-Tomlinson models and their extensions to interpret dry atomic-scale friction. We begin with the fundamental equations and build on them step-by-step from the simple quasistatic one-spring, one-mass model for predicting transitions between friction regimes to the two-dimensional and multi-atom models for describing the effect of contact area. Theoretical analysis, numerical implementation, and predicted physical phenomena are all discussed. In the process, we demonstrate the significant potential for this approach to yield new fundamental understanding of atomic-scale friction. Atomistic modeling can never be overemphasized in the investigation of atomic friction, in which each single atom could play a significant role, but is hard to be captured experimentally. In atomic friction, the interesting physical process is buried between the two contact interfaces, thus makes a direct measurement more difficult. Atomistic simulation is able to simulate the process with the dynamic information of each single atom, and therefore provides valuable interpretations for experiments. In this, we will systematically to apply Molecular Dynamics (MD) simulation to optimally model the Atomic Force Microscopy (AFM) measurement of atomic friction. Furthermore, we also employed molecular dynamics simulation to correlate the atomic dynamics with the friction behavior observed in experiments. For instance, ParRep dynamics (an accelerated molecular dynamic technique) is introduced to investigate velocity dependence of atomic friction; we also employ MD simulation to "see" how the reconstruction of gold surface modulates the friction, and the friction enhancement mechanism at a graphite step edge. Atomic stick-slip friction can be treated as a rate process. Instead of running a direction simulation of the process, we can apply transition state theory to predict its property. We will have a rigorous derivation of velocity and temperature dependence of friction based on the Prandtl-Tomlinson model as well as transition theory. A more accurate relation to prediction velocity and temperature dependence is obtained. Furthermore, we have included instrumental noise inherent in AFM measurement to interpret two discoveries in experiments, suppression of friction at low temperature and the attempt frequency discrepancy between AFM measurement and theoretical prediction. We also discuss the possibility to treat wear as a rate process.

Dong, Yalin

37

Physics with the ALICE experiment  

E-print Network

ALICE experiment at LHC collects data in pp collisions at $\\sqrt{s}$=0.9, 2.76 and 7 TeV and in PbPb collisions at 2.76 TeV. Highlights of the detector performance and an overview of experimental results measured with ALICE in pp and AA collisions are presented in this paper. Physics with proton-proton collisions is focused on hadron spectroscopy at low and moderate $p_T$. Measurements with lead-lead collisions are shown in comparison with those in pp collisions, and the properties of hot quark matter are discussed.

Yuri Kharlov; for the ALICE collaboration

2012-03-09

38

[The physics of coal liquid slurry atomization]. Annual report 1992  

SciTech Connect

In order to understand the physics of atomization and to predict and improve the performance of atomizers, a survey on the effects of turbulence on atomization has been made. The influence of gas turbulence intensity on the disintegration of a liquid jet, while a constant mean velocity in both gas and liquid streams has been maintained, has been studied. A study has been made of the influence of changing dynamic surface tension on liquid surface wave characteristics and atomization. The dynamic surface tension of water was changed by adding Triton X-100 non-ionic surfactant into the liquid supplied to a two dimensional slot atomizer. Wave frequencies were measured using laser beam attenuation. Dynamic surface tension changes were found to influence liquid sheet disintegration with little effect on wave frequencies. A series of experiments have been conducted to determine the fundamental processes of injection and atomization of liquid propellants for rocket combustion chambers because of their direct influence on combustion instability. For coaxial injectors, liquid and gas flow rates have been progressively changed. Microphotography was used to obtain details of wave disturbances on liquid surfaces. Direct measurements were made of wavelength and frequency of wave propagation on liquid surfaces. Frequency was found to remain constant along the length of the liquid surface. Pulsations in the liquid jet caused drops to form clusters with the same frequency as that of jet surface waves. Measured frequencies were in the range of those measured in combustion instability experiments. Detailed measurements have been made in the sprays using the phase Doppler particle analyzer. Measurements of drop size, velocity and number density are related to the disintegration process. Increasing turbulence intensity in the gas stream is a very effective means of reducing drop size, increasing spray width, and therefore, improving combustion.

Chigier, N.; Brown, W.J.

1994-06-01

39

Experiment Design and Analysis Guide - Neutronics & Physics  

SciTech Connect

The purpose of this guide is to provide a consistent, standardized approach to performing neutronics/physics analysis for experiments inserted into the Advanced Test Reactor (ATR). This document provides neutronics/physics analysis guidance to support experiment design and analysis needs for experiments irradiated in the ATR. This guide addresses neutronics/physics analysis in support of experiment design, experiment safety, and experiment program objectives and goals. The intent of this guide is to provide a standardized approach for performing typical neutronics/physics analyses. Deviation from this guide is allowed provided that neutronics/physics analysis details are properly documented in an analysis report.

Misti A Lillo

2014-06-01

40

MISSE Scattered Atomic Oxygen Characterization Experiment  

NASA Technical Reports Server (NTRS)

An experiment designed to measure the atomic oxygen (AO) erosion profile of scattered AO was exposed to Low Earth Orbital (LEO) AO for almost four years as part of the Materials International Space Station Experiment 1 and 2 (MISSE 1 and 2). The experiment was flown in MISSE Passive Experiment Carrier 2 (PEC 2), Tray 1, attached to the exterior of the International Space Station (ISS) Quest Airlock. The experiment consisted of an aperture disk lid of Kapton H (DuPont) polyimide coated on the space exposed surface with a thin AO durable silicon dioxide film. The aperture lid had a small hole in its center to allow AO to enter into a chamber and impact a base disk of aluminum. The AO that scattered from the aluminum base could react with the under side of the aperture lid which was coated sporadically with microscopic sodium chloride particles. Scattered AO erosion can occur to materials within a spacecraft that are protected from direct AO attack but because of apertures in the spacecraft the AO can attack the interior materials after scattering. The erosion of the underside of the Kapton lid was sufficient to be able to use profilometry to measure the height of the buttes that remained after washing off the salt particles. The erosion pattern indicated that peak flux of scattered AO occurred at and angle of approximately 45 from the incoming normal incidence on the aluminum base unlike the erosion pattern predicted for scattering based on Monte Carlo computational predictions for AO scattering from Kapton H polyimide. The effective erosion yield for the scattered AO was found to be a factor of 0.214 of that for direct impingement on Kapton H polyimide.

Banks, Bruce A.; deGroh, Kim K.; Miller, Sharon K.

2006-01-01

41

ELISA, and electrostatic storage ring for atomic physics  

NASA Astrophysics Data System (ADS)

The design of a new type of storage ring for heavy ions using electrostatic deflection and focusing devices is described. At low energy, where the velocity is low for heavy ions, electrostatic bends and quadrupoles are more efficient than magnetic ones. Furthermore, electrostatic devices are more compact and easier to construct than magnetic devices. These and other features, e.g. no magnetic fields, makes such storage rings attractive for many atomic-physics experiments, and also for basic research in neighboring fields such as chemistry and biology.

Møller, Søren Pape

1997-02-01

42

Atomic physics and non-LTE effects  

NASA Astrophysics Data System (ADS)

Pulsed-power-driven z-pinch plasmas are an intense source of soft X-ray radiation producing, on the Z facility, about 2 MJ of total radiation for a number of tungsten loads and in the case of a multiwire titanium array over 1 MJ total radiation and about 100 kJ from the titanium K-shell. The production and transport of radiation in these non-LTE plasmas are often modeled assuming some variation of Local Thermodynamic Equilibrium (LTE) in conjunction with radiation diffusion. Since these plasmas are neither in LTE or entirely opaque or transparent these models do not properly predict the emitted radiation spectra and yield. Also, application of these models overestimates the radiation cooling to the extent that the evolving hydrodynamic profiles are significantly different from those that would obtain using the appropriate non-LTE model with a more realistic treatment of the radiation transport. In this investigation, we discuss the production and transport of radiation from the viewpoint of the microscopic collisional and radiative processes and then apply it to z-pinch plasmas. Through the use of examples and illustrations, it is shown that for identical initial load conditions, atomic level structure, and rate coefficients, the models predict different results that affect the dynamic evolution and hydrodynamic history of the plasma. As an example, the emission spectrum is generated using a 1-D radiation MHD model self-consistently coupled to a circuit representing the Sandia Z facility. A comparison is then made between several standard models of ionization dynamics for a multiwire titanium array. Finally, we address some of the issues regarding how the dense plasma environment influences isolated atom structure and processes. These include, for example, atomic level shifts, ionization lowering, collision cross sections, and collision widths. Transition from the isolated-atom to the dressed-particle picture can modify the ionization physics and emission spectra to such an extent that it may challenge our precepts on how best to design loads for the next generation machine.

Davis, J.; Clark, R.; Blaha, M.; Giuliani, J. L.

2001-10-01

43

Atomic Physics at Storage Rings:. Recent Results from the Esr and Future Perspectives at Fair  

NASA Astrophysics Data System (ADS)

At the Gesellschaft für Schwerionenforschung mbH (GSI), atomic physics research focusses on spectroscopy of simple atomic systems at high-Z, where both the structure as well as the dynamics are determined by extreme electromagnetic fields. The Experimental Storage Ring (ESR) enables us to store these ions for long periods of time, under ideal circumstances, and to perform high-precision experiments. By means of advanced laser, target, and detector technology, we are able to address the still largely unexplored physics of these simple but exotic systems. In this paper we present some important aspects of the current and future atomic physics program, and show recent results from the ESR.

Winters, D. F. A.; Stöhlker, Th.

44

On the utility and ubiquity of atomic collision physics  

NASA Astrophysics Data System (ADS)

This paper is divided into three parts. In the introduction, we discuss the history and makeup of ICPEAC. In the second part, we discuss the extent of applicability of atomic collision physics. In the third part, we chose one subject (dielectronic excitation) to show the interrelationship of various sub-branches of atomic collision physics.

Datz, Sheldon

1990-06-01

45

On the utility and ubiquity of atomic collision physics  

NASA Astrophysics Data System (ADS)

In the introduction, the history and makeup of ICPEAC are discussed. In the second part, the extent of applicability of atomic collision physics is covered. In the third part, one subject (dielectronic excitation) was chosen to show the interrelationship of various subbranches of atomic collision physics.

Datz, Sheldon

46

1. GENERAL VIEW, LOOKING NORTH, OF ATOMIC PHYSICS OBSERVATORY WHICH ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. GENERAL VIEW, LOOKING NORTH, OF ATOMIC PHYSICS OBSERVATORY WHICH CONTAINS THE WHITE DOME STRUCTURE. THE SHED-LIKE STRUCTURE TO THE LEFT IS THE SEARCH-LIGHT BUILDING. - Carnegie Institute of Washington, Department of Terrestrial Magnetism, Atomic Physics Observatory, 5241 Broad Branch Drive Northwest, Washington, District of Columbia, DC

47

On the utility and ubiquity of atomic collision physics  

SciTech Connect

This paper is divided into three parts. In the introduction, we discuss the history and makeup of ICPEAC. In the second part, we discuss the extent of applicability of atomic collision physics. In the third part, we chose one subject (dielectronic excitation) to show the interrelationship of various sub-branches of atomic collision physics. 28 refs., 14 figs.

Datz, S.

1989-01-01

48

Atom Smasher: An Educational Game for Teaching About Accelerators, Detectors and Particle Physics  

NASA Astrophysics Data System (ADS)

An innovative multimedia game called Atom Smasher is being developed to introduce precollege students to the world of particle accelerators, particle detectors, and elementary particle physics. The game includes an animated accelerator facility introduction that places the player in the role of a scientist conducting experiments. Live animated tutorials, movies, a particle physics game show, slide show tutorials and a fast- action game will all be demonstrated as elements of Atom Smasher.

Brown, Nathan; Lancaster, George; Gillespie, George; Hill, Barrey

1998-04-01

49

Atom Smasher: An Educational Game for Teaching About Accelerators, Detectors and Particle Physics  

Microsoft Academic Search

An innovative multimedia game called Atom Smasher is being developed to introduce precollege students to the world of particle accelerators, particle detectors, and elementary particle physics. The game includes an animated accelerator facility introduction that places the player in the role of a scientist conducting experiments. Live animated tutorials, movies, a particle physics game show, slide show tutorials and a

Nathan Brown; George Lancaster; George Gillespie; Barrey Hill

1998-01-01

50

Atomic oxygen exposure of LDEF experiment trays  

NASA Technical Reports Server (NTRS)

Atomic oxygen exposures were determined analytically for rows, longerons, and end bays of the Long Duration Exposure Facility (LDEF). The calculations are based on an analytical model that accounts for the effects of thermal molecular velocity, atmospheric temperature, number density, spacecraft velocity, incidence angle, and atmospheric rotation on atomic oxygen flux. Results incorporate variations in solar activity, geomagnetic index, and orbital parameters occurring over the 6-year flight of the spacecraft. To facilitate use of the data, both detailed tabulations and summary charts for atomic oxygen fluences are presented.

Bourassa, R. J.; Gillis, J. R.

1992-01-01

51

Apparatus for fermion atomic clock, atom interferometry and quantum pumping experiments  

NASA Astrophysics Data System (ADS)

We present the current state of an apparatus designed to create and manipulate ultracold bosonic and fermionic Rb and K isotopes for a fermion atomic clock, atom interferometry, microwave trapping, and quantum pumping experiments. Quantum pumping is a phenomenon which can precisely control bias-less flow of single electrons in a circuit. Using ultracold atoms on atom chips, we can test theoretical predictions which have not yet been verified due to experimental difficulties in solid state systems. The apparatus design consists of a magneto-optical trap, magnetic transport system, atom chip, and optical dipole trap. We have demonstrated basic laser cooling and trapping and are working towards transport of the collected atoms to the atom chip for cooling to quantum degeneracy. Once quantum degeneracy is achieved at the chip, micro-magnetic reservoirs of ultracold atoms connected by a 1D ``wire'' create a circuit for various quantum pumping schemes. These schemes are also more broadly applicable to atomtronics experiments.

Ivory, M. K.; Ziltz, A.; Field, J.; Aubin, S.

2010-03-01

52

Atomic Structure Calculations from the Los Alamos Atomic Physics Codes  

DOE Data Explorer

The well known Hartree-Fock method of R.D. Cowan, developed at Los Alamos National Laboratory, is used for the atomic structure calculations. Electron impact excitation cross sections are calculated using either the distorted wave approximation (DWA) or the first order many body theory (FOMBT). Electron impact ionization cross sections can be calculated using the scaled hydrogenic method developed by Sampson and co-workers, the binary encounter method or the distorted wave method. Photoionization cross sections and, where appropriate, autoionizations are also calculated. Original manuals for the atomic structure code, the collisional excitation code, and the ionization code, are available from this website. Using the specialized interface, you will be able to define the ionization stage of an element and pick the initial and final configurations. You will be led through a series of web pages ending with a display of results in the form of cross sections, collision strengths or rates coefficients. Results are available in tabular and graphic form.

Cowan, R. D.

53

Theoretical Atomic Physics code development IV: LINES, A code for computing atomic line spectra  

SciTech Connect

A new computer program, LINES, has been developed for simulating atomic line emission and absorption spectra using the accurate fine structure energy levels and transition strengths calculated by the (CATS) Cowan Atomic Structure code. Population distributions for the ion stages are obtained in LINES by using the Local Thermodynamic Equilibrium (LTE) model. LINES is also useful for displaying the pertinent atomic data generated by CATS. This report describes the use of LINES. Both CATS and LINES are part of the Theoretical Atomic PhysicS (TAPS) code development effort at Los Alamos. 11 refs., 9 figs., 1 tab.

Abdallah, J. Jr.; Clark, R.E.H.

1988-12-01

54

Precision physics of simple atoms: QED tests, nuclear structure and fundamental constants  

E-print Network

Quantum electrodynamics is the first successful and still the most successful quantum field theory. Simple atoms, being essentially QED systems, allow highly accurate theoretical predictions. Because of their simple spectra, such atoms have been also efficiently studied experimentally frequently offering the most precisely measured quantities. Our review is devoted to comparison of theory and experiment in the field of precision physics of light simple atoms. In particular, we consider the Lamb shift in the hydrogen atom, the hyperfine structure in hydrogen, deuterium, helium-3 ion, muonium and positronium, as well as a number of other transitions in positronium. Additionally to a spectrum of unperturbed atoms, we consider annihilation decay of positronium and the g factor of bound particles in various two-body atoms. Special attention is paid to the uncertainty of the QED calculations due to the uncalculated higher-order corrections and effects of the nuclear structure. We also discuss applications of simple atoms to determination of several fundamental constants.

Savely G. Karshenboim

2005-09-01

55

Explaining Atomic Spectra within Classical Physics: 1897-1913  

Microsoft Academic Search

In this paper we analyse the approach to interpreting atomic spectra in the framework of classical physics from the discovery of the electron in 1897 to Bohr's atomic model of 1913. Taken as a whole, efforts in this direction are part of a remarkable intellectual endeavour in which the classical theoretical framework seems to have been exploited to its full

Bruno Carazza; Nadia Robotti

2002-01-01

56

ATOMIC PHYSICS, AN AUTOINSTRUCTIONAL PROGRAM, VOLUME 2, SUPPLEMENT.  

ERIC Educational Resources Information Center

THE AUTOINSTRUCTIONAL MATERIALS IN THIS TEXT WERE PREPARED FOR USE IN AN EXPERIMENTAL STUDY, OFFERING SELF-TUTORING MATERIAL FOR LEARNING ATOMIC PHYSICS. THE TOPICS COVERED ARE (1) ISOTOPES AND MASS NUMBERS, (2) MEASURING ATOMIC MASS, (3) DISCOVERY OF THE NUCLEUS, (4) STRUCTURE OF THE NUCLEUS, (5) DISCOVERY OF THE NEUTRON, (6) NUCLEAR REACTIONS,…

DETERLINE, WILLIAM A.; KLAUS, DAVID J.

57

Practical Physics: Basic Experiments with Ripple Tanks  

NSDL National Science Digital Library

This resource contains a set of eight introductory experiments on wave reflections, appropriate for use in high school and middle school. Use of the ripple tank can be a powerful tool to help students visualize wave behavior in general. In these basic experiments, students are introduced to ripple tanks and gain confidence in using them by doing some simple experiments with pulses. SEE RELATED ITEMS for a Teachers' Guide on using ripple tanks, and for ripple tank experiments for the more advanced classroom. This item is part of a much larger collection of physics/astronomy experiments, sponsored by the UK's Institute of Physics and funded by the Nuffield Curriculum Centre.

Centre, Nuffield C.

58

Atomic parity-violation and precision physics  

NASA Astrophysics Data System (ADS)

The atomic parity-violation (APV) parameter QW for a nucleus with n neutrons and z protons has been included in the list of pseudo-observables accessible with the codes TOPAZ0 and ZFITTER. In this way one can add the APV results in the LEP EWWG “global” electroweak fits, checking the corresponding effect when added to the existing precision measurements.

Bardin, D.; Christova, P.; Kalinovskaya, L.; Passarino, G.

2001-09-01

59

Atomic physics with highly charged ions  

SciTech Connect

This report discusses: One electron outer shell processes in fast ion-atom collisions; role of electron-electron interaction in two-electron processes; multi-electron processes at low energy; multi-electron processes at high energy; inner shell processes; molecular fragmentation studies; theory; and, JRM laboratory operations.

Richard, P.

1991-08-01

60

The physics of spin polarized atomic vapors  

NASA Astrophysics Data System (ADS)

Research efforts are focussed on the study of spin polarized atoms, nuclei and electrons during the period covered by this report. Although this work is 6.1 basic research, it has applications to a number of important Air Force problems. For example, the atomic clocks used on the GPS satellite system operate with optically pumped rubidium absorption cells, very similar to the ones being investigated here. A number of the scientists and engineers working on atomic clocks used by Air Force satellite systems were trained with the support of this grant. We have participated in recent Air Force advisory panels to review concepts for high-energy-density fuels based on spin polarized atoms and molecules. The insights gained from research sponsored by this grant have been very useful in evaluating these ideas. Recent work has focussed on two main areas, the investigation of quadrupolar interactions between spin polarized noble gas nuclei and surfaces and the quantitative investigation of how magnetic field inhomogeneities cause spin relaxation.

Happer, William

1988-05-01

61

LASSP: The Laboratory of Atomic and Solid State Physics  

NSDL National Science Digital Library

The Laboratory of Atomic and Solid State Physics (LASSP) at Cornell University is a center for research in condensed matter physics. Scientists can read about the work of the thirty faculty members in topics such as theoretical condensed matter physics, low temperature physics, experimental liquid physics, and experimental soft-condensed matter and biological physics. With a number of images and animations at the website, students can learn about diffraction patterns of an icosahedral quasicrystal, Coarsening, and Spiral Defect Turbulence. Physicists can find employment opportunities at LASSP as well as information on upcoming seminars, conferences, and meetings.

62

Los Alamos free atomic tritium beta decay experiment  

SciTech Connect

An apparatus is under construction at Los Alamos to measure the beta spectrum of free tritium atoms and molecules. The tritium atoms decay in a gaseous windowless source and are analyzed by a Tret'yakov type toroidal field beta spectrometer. The ultimate sensitivity of the experiment to electron antineutrino mass is expected to be <10 eV.

Knapp, D.A.; Bowles, T.J.; Browne, J.C.; Burritt, T.H.; Cohen, J.S.; Helffrich, J.A.; Maley, M.P.; Martin, R.L.; Robertson, R.G.H.; Wilkerson, J.F.

1984-01-01

63

Clock Technology Development for the Laser Cooling and Atomic Physics (LCAP) Program  

NASA Technical Reports Server (NTRS)

The Time and Frequency Sciences and Technology Group at Jet Propulsion Laboratory (JPL) has developed a laser cooling capability for flight and has been selected by NASA to support the Laser-Cooling and Atomic Physics (LCAP) program. Current work in the group includes design and development for tee two laser-cooled atomic clock experiments which have been selected for flight on the International Space Station.

Klipstein, W. M.; Thompson, R. J.; Seidel, D. J.; Kohel, J.; Maleki, L.

1998-01-01

64

Positron spectroscopy in atomic and solid state physics  

Microsoft Academic Search

Basic research problems in Atomic Physics with positrons (total cross sections, Ramsauer minima, positronium formation, selective ionization) and some benchmark measurements in Solid State Physics using positron annihilation (He-created nano-voids in Si, Oxygen precipitates in Si, low ? materials) are discussed.

G. P. Karwasz; R. S. Brusa; A. Zecca

2003-01-01

65

Current experiments in elementary-particle physics  

NASA Astrophysics Data System (ADS)

Microfiche are included which contain summaries of 479 experiments in elementary particle physics. Experiments are included at the following laboratories: Brookhaven (ENL); CERN; DESY; Fermilab. (FNAL); Institute for Nuclear Studies (INS); KEK; LAMPF; Serpukhov (SERP); SIN; SLAC; and TRIUMP. Also, summries of proton decay experiments are included. A list of experiments and titles is included; and a beam-target-momentum index and a spokesperson index are given. Properties of beams at the facilities are tabulated.

Wohl, C. G.; Armstrong, F. E.; Rittenberg, A.

1983-03-01

66

Current experiments in elementary particle physics  

SciTech Connect

This report contains summaries of 736 current and recent experiments in elementary particle physics (experiments that finished taking data before 1982 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, Joint Institute for Nuclear Research (Dubna), KEK, LAMPF, Novosibirsk, PSI/SIN, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground experiments. Also given are instructions for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

Wohl, C.G.; Armstrong, F.E.; Trippe, T.G.; Yost, G.P. (Lawrence Berkeley Lab., CA (USA)); Oyanagi, Y. (Tsukuba Univ., Ibaraki (Japan)); Dodder, D.C. (Los Alamos National Lab., NM (USA)); Ryabov, Yu.G.; Slabospitsky, S.R. (Gosudarstvennyj Komitet po Ispol'zovaniyu Atomnoj Ehnergii SSSR, Serpukhov (USSR). Inst. Fiziki Vysokikh Ehnergij); Frosch, R. (Swiss Inst. for Nuclear Research, Villigen (Switzerla

1989-09-01

67

Current experiments in elementary particle physics. Revised  

SciTech Connect

This report contains summaries of 584 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1986 are excluded. Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, KEK, LAMPF, Novosibirsk, Paul Scherrer Institut (PSI), Saclay, Serpukhov, SLAC, SSCL, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

Galic, H. [Stanford Univ., CA (United States). Stanford Linear Accelerator Center; Wohl, C.G.; Armstrong, B. [Lawrence Berkeley Lab., CA (United States); Dodder, D.C. [Los Alamos National Lab., NM (United States); Klyukhin, V.I.; Ryabov, Yu.G. [Inst. for High Energy Physics, Serpukhov (Russian Federation); Illarionova, N.S. [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation); Lehar, F. [CEN Saclay, Gif-sur-Yvette (France); Oyanagi, Y. [Univ. of Tokyo (Japan). Faculty of Sciences; Olin, A. [TRIUMF, Vancouver, BC (Canada); Frosch, R. [Paul Scherrer Inst., Villigen (Switzerland)

1992-06-01

68

The Common Elements of Atomic and Hadronic Physics  

E-print Network

Atomic physics and hadronic physics are both governed by the Yang Mills gauge theory Lagrangian; in fact, Abelian quantum electrodynamics can be regarded as the zero-color limit of quantum chromodynamics. I review a number of areas where the techniques of atomic physics can provide important insight into hadronic eigenstates in QCD. For example, the Dirac-Coulomb equation, which predicts the spectroscopy and structure of hydrogenic atoms, has an analog in hadron physics in the form of frame-independent light-front relativistic equations of motion consistent with light-front holography which give a remarkable first approximation to the spectroscopy, dynamics, and structure of light hadrons. The production of antihydrogen in flight can provide important insight into the dynamics of hadron production in QCD at the amplitude level. The renormalization scale for the running coupling is unambiguously set in QED; an analogous procedure sets the renormalization scales in QCD, leading to scheme-independent scale-fixed...

Brodsky, Stanley J

2015-01-01

69

Lithium atom interferometer using laser diffraction : description and experiments  

E-print Network

We have built and operated an atom interferometer of the Mach-Zehnder type. The atomic wave is a supersonic beam of lithium seeded in argon and the mirrors and beam-splitters for the atomic wave are based on elastic Bragg diffraction on laser standing waves at 671 nm. We give here a detailed description of our experimental setup and of the procedures used to align its components. We then present experimental signals, exhibiting atomic interference effects with a very high visibility, up to 84.5 %. We describe a series of experiments testing the sensitivity of the fringe visibility to the main alignment defects and to the magnetic field gradient.

Alain Miffre; Marion Jacquey; Matthias Büchner; Gérard Trenec; Jacques Vigue

2005-04-08

70

PHYSICAL REVIEW A 88, 043429 (2013) Coherent manipulation of cold Rydberg atoms near the surface of an atom chip  

E-print Network

PHYSICAL REVIEW A 88, 043429 (2013) Coherent manipulation of cold Rydberg atoms near the surface of an atom chip J. D. Carter and J. D. D. Martin Department of Physics and Astronomy and Institute atoms were studied near the surface of an atom chip. The superpositions were created and manipulated

Le Roy, Robert J.

71

Physics of polarized scattering at multi-level atomic systems  

E-print Network

The symmetric peak observed in linear polarization in the core of the solar sodium D$_1$ line at 5896 \\AA\\ has remained enigmatic since its discovery nearly two decades ago. One reason is that the theory of polarized scattering has not been experimentally tested for multi-level atomic systems in the relevant parameter domains, although the theory is continually being used for the interpretation of astrophysical observations. A laboratory experiment that was set up a decade ago to find out whether the D$_1$ enigma is a problem of solar physics or quantum physics revealed that the D$_1$ system has a rich polarization structure in situations where standard scattering theory predicts zero polarization, even when optical pumping of the $m$ state populations of the hyperfine-split ground state is accounted for. Here we show that the laboratory results can be modeled in great quantitative detail if the theory is extended to include the coherences in both the initial and final states of the scattering process. Radiat...

Stenflo, Jan

2015-01-01

72

University of Oregon Physics Applets: Atomic Emission  

NSDL National Science Digital Library

This applet presents the user with an energy level diagram of an atom. The values of the levels (in eV) can be set by parameter tags. Relative transition probabilities can also be set by parameter tags. An active electron can be moved to any level by using the pointing device and then the electron will cascade down to the ground level according to the relative transition probabilities that have been set up. Each time the electron moves from a higher to lower energy level a photon will be emitted. The wavelength of the photon is indicated and some attempt is to color code the outgoing photon by the emitted wavelength.

Bothun, Gregory

2007-01-09

73

Hypergeometric integrals arising in atomic collisions physics  

SciTech Connect

We introduce a method of obtaining volume integrals involving confluent hypergeometric functions. This method is based on the integral representation of these functions and enabled us to write a generalized Nordsieck integral in terms of hypergeometric functions of many variables. We explore some particular results that could be useful when calculating transition matrices in collision theories. {copyright} {ital 1997 American Institute of Physics.}

Colavecchia, F.D.; Gasaneo, G.; Garibotti, C.R. [Centro Atomico Bariloche and Consejo Nacional de Investigaciones Cientificas y Tecnicas, 8400 San Carlos de Bariloche (Argentina)] [Centro Atomico Bariloche and Consejo Nacional de Investigaciones Cientificas y Tecnicas, 8400 San Carlos de Bariloche (Argentina)

1997-12-01

74

Atoms in Flight: The Remarkable Connections between Atomic and Hadronic Physics  

SciTech Connect

Atomic physics and hadron physics are both based on Yang Mills gauge theory; in fact, quantum electrodynamics can be regarded as the zero-color limit of quantum chromodynamics. I review a number of areas where the techniques of atomic physics provide important insight into the theory of hadrons in QCD. For example, the Dirac-Coulomb equation, which predicts the spectroscopy and structure of hydrogenic atoms, has an analog in hadron physics in the form of light-front relativistic equations of motion which give a remarkable first approximation to the spectroscopy, dynamics, and structure of light hadrons. The renormalization scale for the running coupling, which is unambiguously set in QED, leads to a method for setting the renormalization scale in QCD. The production of atoms in flight provides a method for computing the formation of hadrons at the amplitude level. Conversely, many techniques which have been developed for hadron physics, such as scaling laws, evolution equations, and light-front quantization have equal utility for atomic physics, especially in the relativistic domain. I also present a new perspective for understanding the contributions to the cosmological constant from QED and QCD.

Brodsky, Stanley J.; /SLAC

2012-02-16

75

Low-Cost Accelerometers for Physics Experiments  

ERIC Educational Resources Information Center

The implementation of a modern game-console controller as a data acquisition interface for physics experiments is discussed. The investigated controller is equipped with three perpendicular accelerometers and a built-in infrared camera to evaluate its own relative position. A pendulum experiment is realized as a demonstration of the proposed…

Vannoni, Maurizio; Straulino, Samuele

2007-01-01

76

PHYSICAL REVIEW A 83, 063631 (2011) Momentum distribution and ordering in mixtures of ultracold light-and heavy-fermion atoms  

E-print Network

light- and heavy-fermion atoms M. M. Ma´ska Department of Theoretical Physics, Institute of Physics, we consider mixtures of light- and heavy-fermionic atoms in an optical lattice described effectively, the pattern formed by the heavy atoms seen in the Bragg scattering experiments is very sensitive

Freericks, Jim

77

Current Experiments in Particle Physics (September 1996)  

SciTech Connect

This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries. This report contains full summaries of 180 approved current and recent experiments in elementary particle physics. The focus of the report is on selected experiments which directly contribute to our better understanding of elementary particles and their properties such as masses, widths or lifetimes, and branching fractions.

Galic, H.; Lehar, F.; Klyukhin, V.I.; Ryabov, Yu.G.; Bilak, S.V.; Illarionova, N.S.; Khachaturov, B.A.; Strokovsky, E.A.; Hoffman, C.M.; Kettle, P.-R.; Olin, A.; Armstrong, F.E.

1996-09-01

78

COMPILATION OF CURRENT HIGH ENERGY PHYSICS EXPERIMENTS  

SciTech Connect

This is the fourth edition of our compilation of current high energy physics experiments. It is a collaborative effort of the Berkeley Particle Data Group, the SLAC library, and nine participating laboratories: Argonne (ANL), Brookhaven (BNL), CERN, DESY, Fermilab (FNAL), the Institute for Nuclear Study, Tokyo (INS), KEK, Serpukhov (SERP), and SLAC. The compilation includes summaries of all high energy physics experiments at the above laboratories that (1) were approved (and not subsequently withdrawn) before about April 1981, and (2) had not completed taking of data by 1 January 1977. We emphasize that only approved experiments are included.

Wohl, C.G.; Kelly, R.L.; Armstrong, F.E.; Horne, C.P.; Hutchinson, M.S.; Rittenberg, A.; Trippe, T.G.; Yost, G.P.; Addis, L.; Ward, C.E.W.; Baggett, N.; Goldschmidt-Clermong, Y.; Joos, P.; Gelfand, N.; Oyanagi, Y.; Grudtsin, S.N.; Ryabov, Yu.G.

1981-05-01

79

Preliminary results of an atomic oxygen spaceflight experiment  

Microsoft Academic Search

An atomic oxygen (AO) experiment designed to measure the AO environment and the erosion rate of selected materials is currently flying on a microsatellite (STRV-la). The experiment comprised four bare silver resistance sensors and eight silver sensors with thin film overlays of polyethylene, PTFE, carbon and silica. Preliminary analysis of the results from the bare silver films shows good agreement

I. L. Harris; A. R. Chambers; G. T. Roberts

1997-01-01

80

Highlights INFM 2000/2001 1.Atomic and Molecular Physics, Quantum Electronics and Plasma Physics  

E-print Network

Highlights INFM 2000/2001 1.Atomic and Molecular Physics, Quantum Electronics and Plasma Physics 1.2 EXPERIMENTAL CHARACTERIZATION OF THE TRANSFER MATRIX OF A QUANTUM DEVICE It is unquestionable that the current, processing, storing, or computing. The marriage of Quantum Physics and Information Technology -originally

D'Ariano, Giacomo Mauro

81

Resource Article: Experiments with Vortices in Superfluid Atomic Gases  

Microsoft Academic Search

Observations of quantized vortices in dilute-gas Bose-Einstein condensates were first reported in 1999. Over the next 10 years, more than 70 papers describing experiments involving vortices in superfluid atomic gases were published in scientific journals. This resource article provides a guide to the published experimental studies related to quantized vortices in atomic Bose-Einstein condensates and superfluid Fermi gases. A BibTex-formatted

Brian P. Anderson

2010-01-01

82

Resource Article: Experiments with Vortices in Superfluid Atomic Gases  

Microsoft Academic Search

Observations of quantized vortices in dilute-gas Bose-Einstein condensates were first reported in 1999. Over the next 10 years,\\u000a more than 70 papers describing experiments involving vortices in superfluid atomic gases were published in scientific journals.\\u000a This resource article provides a guide to the published experimental studies related to quantized vortices in atomic Bose-Einstein\\u000a condensates and superfluid Fermi gases. A BibTex-formatted

Brian P. Anderson

2010-01-01

83

Majorana: From Atomic and Molecular, to Nuclear Physics  

NASA Astrophysics Data System (ADS)

In the centennial of Ettore Majorana's birth (1906-1938?), we re-examine some aspects of his fundamental scientific production in atomic and molecular physics, including a not well known short communication. There, Majorana critically discusses Fermi's solution of the celebrated Thomas-Fermi equation for electron screening in atoms and positive ions. We argue that some of Majorana's seminal contributions in molecular physics already prelude to the idea of exchange interactions (or Heisenberg-Majorana forces) in his later workson theoretical nuclear physics. In all his papers, he tended to emphasize the symmetries at the basis of a physical problem, as well as the limitations, rather than the advantages, of the approximations of the method employed.

Pucci, R.; Angilella, G. G. N.

2006-10-01

84

HISTRAP proposal: heavy ion storage ring for atomic physics  

SciTech Connect

HISTRAP, Heavy Ion Storage Ring for Atomic Physics, is a proposed 46.8-m-circumference synchrotron-cooling-storage ring optimized to accelerate, decelerate, and store beams of highly charged very-heavy ions at energies appropriate for advanced atomic physics research. The ring is designed to allow studies of electron-ion, photon-ion, ion-atom, and ion-ion interactions. An electron cooling system will provide ion beams with small angular divergence and energy spread for precision spectroscopic studies and also is necessary to allow the deceleration of heavy ions to low energies. HISTRAP will have a maximum bending power of 2.0 Tm and will be injected with ions from either the existing Holifield Heavy Ion Research Facility 25-MV tandem accelerator or from a dedicated ECR source and 250 keV/nucleon RFQ linac.

Olsen, D.K.; Alton, G.D.; Datz, S.; Dittner, P.F.; Dowling, D.T.; Haynes, D.L.; Hudson, E.D.; Johnson, J.W.; Lee, I.Y.; Lord, R.S.

1986-11-01

85

True\\/untrue explanations in Physics: the Bohr's atom model  

Microsoft Academic Search

In this note, and inspired by an article appeared recently in this journal, we discuss an example related to the theory of the Bohr's atom, who illustrates the fact that erroneous expositions in the learning of Physics exist, considering that this concept includes the use of well internationally recognized and commonly used educational text books.

E. Marín

2008-01-01

86

Project Physics Reader 5, Models of the Atom.  

ERIC Educational Resources Information Center

As a supplement to Project Physics Unit 5, a collection of articles is presented in this reader for student browsing. Nine excerpts are given under the following headings: failure and success, Einstein, Mr. Tompkins and simultaneity, parable of the surveyors, outside and inside the elevator, the teacher and the Bohr theory of atom, Dirac and Born,…

Harvard Univ., Cambridge, MA. Harvard Project Physics.

87

ATOMIC PHYSICS, AN AUTOINSTRUCTIONAL PROGRAM, VOLUME 4, SUPPLEMENT.  

ERIC Educational Resources Information Center

THE AUTOINSTRUCTIONAL MATERIALS IN THIS TEXT WERE PREPARED FOR USE IN AN EXPERIMENTAL STUDY, OFFERING SELF-TUTORING MATERIAL FOR LEARNING ATOMIC PHYSICS. THE TOPICS COVERED ARE (1) RADIATION USES AND NUCLEAR FISSION, (2) NUCLEAR REACTORS, (3) ENERGY FROM NUCLEAR REACTORS, (4) NUCLEAR EXPLOSIONS AND FUSION, (5) A COMPREHENSIVE REVIEW, AND (6) A…

DETERLINE, WILLIAM A.; KLAUS, DAVID J.

88

Bringing atomic and nuclear physics laboratory data into the classroom  

SciTech Connect

To illustrate a number of basic concepts in atomic and nuclear physics, we have developed three websites where students can analyze data from modern laboratories. By working through the on-line procedures, students will become acquainted with characteristic x-ray spectra, the concept of half-life, x-ray fluorescence, and neutron activation analysis.

Norman, Eric B.; Larimer, Ruth-Mary; Rech, Gregory; Lee, Jeffrey; Vue, Chue; Leubane, Tholoana; Zamvil, Kenneth; Guthrie, Laura

2003-05-27

89

Axiomatizing physical experiments as oracles to algorithms.  

PubMed

We developed earlier a theory of combining algorithms with physical systems, on the basis of using physical experiments as oracles to algorithms. Although our concepts and methods are general, each physical oracle requires its own analysis, on the basis of some fragment of physical theory that specifies the equipment and its behaviour. For specific examples of physical systems (mechanical, optical, electrical), the computational power has been characterized using non-uniform complexity classes. The powers of the known examples vary according to assumptions on precision and timing but seem to lead to the same complexity classes, namely P/log* and BPP//log*. In this study, we develop sets of axioms for the interface between physical equipment and algorithms that allow us to prove general characterizations, in terms of P/log* and BPP//log*, for large classes of physical oracles, in a uniform way. Sufficient conditions on physical equipment are given that ensure a physical system satisfies the axioms. PMID:22711864

Beggs, Edwin J; Costa, José Félix; Tucker, John V

2012-07-28

90

PHYSICAL REVIEW A 81, 063411 (2010) Spatially resolved excitation of Rydberg atoms and surface effects on an atom chip  

E-print Network

PHYSICAL REVIEW A 81, 063411 (2010) Spatially resolved excitation of Rydberg atoms and surface effects on an atom chip Atreju Tauschinsky,* Rutger M. T. Thijssen, S. Whitlock, H. B. van Linden van den spatially resolved, coherent excitation of Rydberg atoms on an atom chip. Electromagnetically induced

Amsterdam, Universiteit van

91

Thermal Sensitive Foils in Physics Experiments  

ERIC Educational Resources Information Center

The paper describes a set of physics demonstration experiments where thermal sensitive foils are used for the detection of the two dimensional distribution of temperature. The method is used for the demonstration of thermal conductivity, temperature change in adiabatic processes, distribution of electromagnetic radiation in a microwave oven and…

Bochnícek, Zdenek; Konecný, Pavel

2014-01-01

92

Thermal sensitive foils in physics experiments  

NASA Astrophysics Data System (ADS)

The paper describes a set of physics demonstration experiments where thermal sensitive foils are used for the detection of the two dimensional distribution of temperature. The method is used for the demonstration of thermal conductivity, temperature change in adiabatic processes, distribution of electromagnetic radiation in a microwave oven and detection of resonant acoustic oscillations in a Rubens’ tube.

Bochní?ek, Zden?k; Kone?ný, Pavel

2014-07-01

93

Atomic physics with highly charged ions. Progress report  

SciTech Connect

The study of inelastic collision phenomena with highly charged projectile ions and the interpretation of spectral features resulting from these collisions remain as the major focal points in the atomic physics research at the J.R. Macdonald Laboratory, Kansas State University, Manhattan, Kansas. The title of the research project, ``Atomic Physics with Highly Charged Ions,`` speaks to these points. The experimental work in the past few years has divided into collisions at high velocity using the primary beams from the tandem and LINAC accelerators and collisions at low velocity using the CRYEBIS facility. Theoretical calculations have been performed to accurately describe inelastic scattering processes of the one-electron and many-electron type, and to accurately predict atomic transition energies and intensities for x rays and Auger electrons. Brief research summaries are given for the following: (1) electron production in ion-atom collisions; (2) role of electron-electron interactions in two-electron processes; (3) multi-electron processes; (4) collisions with excited, aligned, Rydberg targets; (5) ion-ion collisions; (6) ion-molecule collisions; (7) ion-atom collision theory; and (8) ion-surface interactions.

Richard, P.

1994-08-01

94

Sustained Spheromak Physics Experiment (SSPX): design and physics results  

NASA Astrophysics Data System (ADS)

The Sustained Spheromak Physics Experiment (SSPX) was a high-temperature (Te up to 0.5 keV) spheromak formed by coaxial helicity injection (CHI) and with plasma duration of a few milliseconds following the high-current formation stage. Clean walls and low impurity operation were obtained by a combination of baking, discharge cleaning and titanium deposition on the walls, allowing the generation of high-quality plasmas. Resistive-magnetohydrodynamic simulations, benchmarked to the experiment, were used to elucidate the physics. The detailed characteristics of the n? = 1 toroidal mode associated with CHI were determined as was the physics of the nonlinear current drive and magnetic reconnection that formed and sustained the spheromak. If the helicity injection rate was reduced following formation the plasma became relatively quiescent and magnetic surfaces formed. The measured thermal diffusivity in the core was as low as ˜1 m2 s-1. However, reconnection events during buildup or sustainment of the plasma current by CHI were found to open magnetic surfaces throughout the plasma allowing rapid energy loss to the walls. As a result, experiments and simulations in SSPX found no path to simultaneous sustainment by CHI and good energy confinement. Additional physics results are also presented in this review.

Hooper, E. B.; Bulmer, R. H.; Cohen, B. I.; Hill, D. N.; Holcomb, C. T.; Hudson, B.; McLean, H. S.; Pearlstein, L. D.; Romero-Talamás, C. A.; Sovinec, C. R.; Stallard, B. W.; Wood, R. D.; Woodruff, S.

2012-11-01

95

Long Pulse Fusion Physics Experiments Without Superconducting Electromagnets  

E-print Network

Long Pulse Fusion Physics Experiments Without Superconducting Electromagnets Robert D. Woolley fusion physics experiments can be performed economically via resistive electromagnets designed for thermally steady-state operation. Possible fusion experiments using resistive electromagnets include long

96

Long Pulse Fusion Physics Experiments Without Superconducting Electromagnets  

E-print Network

Long Pulse Fusion Physics Experiments Without Superconducting Electromagnets Robert D. Woolley fusion physics experiments can be performed economically via resistive electromagnets designed for thermally steady­state operation. Possible fusion experiments using resistive electromagnets include long

97

Current Topics in Atomic, Molecular and Optical Physics  

NASA Astrophysics Data System (ADS)

Preface -- Ultrafast dynamics of nano and mesoscopic systems driven by asymmetric electromagnetic pulses / A. Matos-Abiague, A. S. Moskalenko and J. Berakdar -- One-dimensional non-linear oscillators as models for atoms and molecules under intense laser fields / A. Wadehra and B. M. Deb -- Experimenting with topological states of Bose-Einstein condensates / C. Raman -- Laser cooling and trapping of Rb atoms / S. Chakraborty ... [et al.] -- Pair-correlation in Bose-Einstein condensate and fermi superfluid of atomic gases / B. Deb -- Properties of trapped Bose gas in the large-gas-parameter regime / A. Banerjee -- A Feynman-Kac path integral study of Rb gas / S. Datta -- Mean field theory for interacting spin-1 bosons on a lattice / R. V. Pai, K. Sheshadri and R. Pandit -- Mixed internal-external state approach for quantum computation with neutral atoms on atom chips / E. Charron ... [et al.] -- Ultrafast pulse shaping developments for quantum computation / S. K. Karthick Kumar and D. Goswami -- Quantum information transfer in atom-photon interactions in a cavity / A. S. Majumdar, N. Nayak and B. Ghosh -- Liouville density evolution in billiards and the quantum connection / D. Biswas -- MRCPA: theory and application to highly correlating system / K. Tanaka -- Calculation of negative ion shape resonances using coupled cluster theory / Y. Sajeev and S. Pal -- Optical frequency standard with Sr+: a theoretical many-body approach / C. Sur ... [et al.] -- Fast heavy ion collisions with H[symbol] molecules and young type interference / L. C. Tribedi and D. Misra -- Estimation of ion kinetic energies from time-of-flight and momentum spectra / B. Bapat -- Third-order optical susceptibility of metal nanocluster-glass 28 composites / B. Ghosh and P. Chakraborty -- Study of atom-surface interaction using magnetic atom mirror / A. K. Mohapatra.

Sinha, Chandana; Bhattacharyya, Shib Shankar

98

Application of ECR ion source beams in atomic physics  

SciTech Connect

The availability of intense, high charge state ion beams from ECR ion sources has had significant impact not only on the upgrading of cyclotron and synchrotron facilities, but also on multicharged ion collision research, as evidenced by the increasing number of ECR source facilities used at least on a part time basis for atomic physics research. In this paper one such facility, located at the ORNL ECR source, and dedicated full time to the study of multicharged ion collisions, is described. Examples of applications of ECR ion source beams are given, based on multicharged ion collision physics studies performed at Oak Ridge over the last few years. 21 refs., 18 figs., 2 tabs.

Meyer, F.W.

1987-01-01

99

Theoretical atomic physics code development I: CATS: Cowan Atomic Structure Code  

SciTech Connect

An adaptation of R.D. Cowan's Atomic Structure program, CATS, has been developed as part of the Theoretical Atomic Physics (TAPS) code development effort at Los Alamos. CATS has been designed to be easy to run and to produce data files that can interface with other programs easily. The CATS produced data files currently include wave functions, energy levels, oscillator strengths, plane-wave-Born electron-ion collision strengths, photoionization cross sections, and a variety of other quantities. This paper describes the use of CATS. 10 refs.

Abdallah, J. Jr.; Clark, R.E.H.; Cowan, R.D.

1988-12-01

100

Adapting Transformative Experience Surveys to Undergraduate Physics  

NSDL National Science Digital Library

Transformative experience (TE) is a theoretical construct intended to capture the extent to which science concepts learned in the classroom shape students' everyday meaning-making and engagement with science outside the classroom. One tool available to assess the depth and prevalence of TE is with surveys. We have been adapting existing surveys for use in various undergraduate physics courses at two different institutions, including algebra-based introductory physics courses and physical science courses for pre-service elementary teachers. We describe our efforts to modify existing surveys for use across different courses and content areas and describe our initial findings concerning the depth and prevalence of TE. From survey data, large differences can be detected in both the depth of students' overall engagement and the degree to which that engagement falls off when students are not in the classroom or working on required assignments.

Frank, Brian W.; Atkins, Leslie J.

2014-01-31

101

TerascaleTerascale computational atomiccomputational atomic physics for the plasma edgephysics for the plasma edge  

E-print Network

Fusion Atomic Data Center, ORNL www-cfadc.phy.ornl.gov Atomic Data and Analysis Structure InternationalTerascaleTerascale computational atomiccomputational atomic physics for the plasma edgephysics Hallam University #12;Direct Dissemination of Atomic DataDirect Dissemination of Atomic Data Controlled

102

Atomic physics at the Advanced Photon Source: Workshop report  

SciTech Connect

The first Workshop on Atomic Physics at the Advanced Photon Source was held at Argonne National Laboratory on March 29--30, 1990. The unprecedented brightness of the Advanced Photon Source (APS) in the hard X-ray region is expected to make possible a vast array of new research opportunities for the atomic-physics community. Starting with discussions of the history and current status of the field, presentations were made on various future directions for research with hard X-rays interacting with atoms, ions, clusters, and solids. Also important were the discussions on the design and status of the four next-generation rings coming on line during the 1990's: the ALS 1.6 GeV ring at Berkeley; the ESRF 6.0-GeV ring at Grenoble (1993); the APS 7.0-GeV ring at Argonne (1995); and the SPring-8 8.0-GeV ring in Japan (1998). The participation of more than one hundred scientists from domestic as well as foreign institutions demonstrated a strong interest in this field. We plan to organize follow-up workshops in the future emphasizing specific research topics.

Not Available

1990-10-01

103

Physics of colloids in space experiment  

NASA Astrophysics Data System (ADS)

The Physics of Colloids in Space (PCS) experiment was proposed by investigators Weitz and Pusey. It is scheduled to be conducted on the International Space Station (ISS) in the year 2000. The broader objective is to study physics of colloidal particles dispersed in a fluid. This includes nucleation and growth of colloidal crystals and behavior of binary colloidal crystal alloys. The structure and properties of colloidal particles with attractive interactions (depletion interactions) induced by the addition of a non-adsorbing polymer, behavior of large-scale fractal aggregates, and gels will also be studied. A multi-purpose light scattering apparatus will be employed in these studies. This apparatus is being designed and built by the NASA Lewis Research Center and is capable of performing dynamic light scattering (DLS), static light scattering (SLS), and Bragg scattering experiments. The flight experiment hardware will be located on the EXPRESS rack mounted in the ISS US Laboratory Module. It is anticipated that the long-term benefit of this research will be to fabricate novel materials that may have applications in opto-electronic display technology. Materials could be fabricated that could act as light switches and could control the direction or color of the displayed light.

Ansari, Rafat R.; Hovenac, Edward A.; Sankaran, Subramanian; Koudelka, John M.; Weitz, David A.; Cipelletti, Luca; Segre, Phillip N.

1999-01-01

104

A Data Readout Approach for Physics Experiment  

E-print Network

With the increasing physical event rate and number of electronic channels, traditional readout scheme meets the challenge of improving readout speed caused by the limited bandwidth of crate backplane. In this paper, a high-speed data readout method based on Ethernet is designed for each module to have capability of transmitting data to DAQ. Features of explicitly parallel data transmitting and distributed network architecture make the readout system has advantage of adapting varying requirements of particle physics experiments. Furthermore, to guarantee the readout performance and flexibility, a standalone embedded CPU system is utilized for network protocol stack processing. To receive customized data format and protocol from front-end electronics, a field programmable gate array (FPGA) is used for logic reconfiguration. To optimize the interface and improve the data swap speed between CPU and FPGA, a sophisticated method based on SRAM is presented in this paper. For the purpose of evaluating this high-speed...

Xi-Ru, Huang; Li-Wei, Gao; Jia-Jun, Zheng

2014-01-01

105

HISTRAP proposal: heavy ion storage ring for atomic physics  

SciTech Connect

HISTRAP is a proposed synchrotron-cooling-storage ring optimized to accelerate, decelerate, and store beams of highly charged very-heavy ions at energies appropriate for advanced atomic physics research. The ring is designed to allow studies of electron-ion, photon-ion, ion-atom, and ion-ion interactions. An electron cooling system will provide ion beams with small angular divergence and energy spread for precision spectroscopic studies and also is necessary to allow the deceleration of heavy ions to low energies. HISTRAP will be injected with ions from either the existing Holifield Heavy Ion Research Facility 25-MV tandem accelerator or from a dedicated ECR source and 250 keV/nucleon RFQ linac. The ring will have a maximum bending power of 2.0 T.m and have a circumference of 46.8 m.

Olsen, D.K.; Alton, G.D.; Datz, S.; Dittner, P.F.; Dowling, D.T.; Haynes, D.L.; Hudson, E.D.; Johnson, J.W.; Lee, I.Y.; Lord, R.S.

1986-01-01

106

Tokamak physics experiment: Diagnostic windows study  

SciTech Connect

We detail the study of diagnostic windows and window thermal stress remediation in the long-pulse, high-power Tokamak Physics Experiment (TPX) operation. The operating environment of the TPX diagnostic windows is reviewed, thermal loads on the windows estimated, and cooling requirements for the windows considered. Applicable window-cooling technology from other fields is reviewed and its application to the TPX windows considered. Methods for TPX window thermal conditioning are recommended, with some discussion of potential implementation problems provided. Recommendations for further research and development work to ensure performance of windows in the TPX system are presented.

Merrigan, M.; Wurden, G.A.

1995-11-01

107

MISSE 6 Stressed Polymers Experiment Atomic Oxygen Erosion Data  

NASA Technical Reports Server (NTRS)

Polymers and other oxidizable materials used on the exterior of spacecraft in the low Earth orbit (LEO) space environment can be eroded away by reaction with atomic oxygen (AO). For spacecraft design, it is important to know the LEO AO erosion yield, Ey (volume loss per incident oxygen atom), of materials susceptible to AO erosion. The Stressed Polymers Experiment was developed and flown as part of the Materials International Space Station Experiment 6 (MISSE 6) to compare the AO erosion yields of stressed and non-stressed polymers to determine if erosion is dependent upon stress while in LEO. The experiment contained 36 thin film polymer samples that were exposed to ram AO for 1.45 years. This paper provides an overview of the Stressed Polymers Experiment with details on the polymers flown, the characterization techniques used, the AO fluence, and the erosion yield results. The MISSE 6 data are compared to data for similar samples flown on previous MISSE missions to determine fluence or solar radiation effects on erosion yield.

deGroh, Kim K.; Banks, Bruce A.; Mitchell, Gianna G.; Yi, Grace T.; Guo, Aobo; Ashmeade, Claire C.; Roberts, Lily M.; McCarthy, Catherine E.; Sechkar, Edward A.

2013-01-01

108

MOLAT: Atomic and Molecular Physics Databases of the Paris Observatory  

NASA Astrophysics Data System (ADS)

MOLAT (http://molat.obspm.fr/) is a joint project of several departments of the Paris Observatory supported by its Scientific Council. Its purpose is to make available original atomic and molecular data and compilations produced independently or in the course of collaborations by members of the Observatory. The data are of interest for the interpretation of observations made by spaceborne or ground based instruments and of laboratory experiments. The experimental data include mainly VUV spectroscopic data obtained by the Meudon group using either the 10m high resolution VUV spectrograph of the Meudon Observatory or the LURE-Orsay synchrotron facility. The theoretical data include calculations from different groups of the Observatory concerning atomic or molecular structures, radiative transition probabilities, collisional excitation cross-sections and line broadening parameters. The bibliographic compilations are maintained by members of the Observatory. The database also provides a selection of links to other pertinent atomic or molecular databases thus serving as a gateway between atomic and molecular physicists and astrophysicists. The data formats have been kept as provided by the authors. An effort is underway to give a unified presentation.

Bruston, M.; Cornille, M.; Dubau, J.; Eidelsberg, M.; Lesage, A.; Launay, F.; Rostas, F.; Spielfiedel, A.; Tchang-Brillet, W.-Ü. L.

2004-12-01

109

The Low Temperature Microgravity Physics Experiments Project  

NASA Technical Reports Server (NTRS)

The Low Temperature Microgravity Physics Facility (LTMPF) is being developed by NASA to provide long duration low temperature and microgravity environment on the International Space Station (ISS) for performing fundamental physics investigations. Currently, six experiments have been selected for flight definition studies. More will be selected in a two-year cycle, through NASA Research Announcement. This program is managed under the Low Temperature Microgravity Physics Experiments Project Office at the Jet Propulsion Laboratory. The facility is being designed to launch and returned to earth on a variety of vehicles including the HII-A and the space shuttle. On orbit, the facility will be connected to the Exposed Facility on the Japanese Experiment Module, Kibo. Features of the facility include a cryostat capable of maintaining super-fluid helium at a temperature of 1.4 K for 5 months, resistance thermometer bridges, multi-stage thermal isolation system, thermometers capable of pico-Kelvin resolution, DC SQUID magnetometers, passive vibration isolation, and magnetic shields with a shielding factor of 80dB. The electronics and software architecture incorporates two VME buses run using the VxWorks operating system. Technically challenging areas in the design effort include the following: 1) A long cryogen life that survives several launch and test cycles without the need to replace support straps for the helium tank. 2) The minimization of heat generation in the sample stage caused by launch vibration 3) The design of compact and lightweight DC SQUID electronics. 4) The minimization of RF interference for the measurement of heat at pico-Watt level. 5) Light weighting of the magnetic shields. 6) Implementation of a modular and flexible electronics and software architecture. The first launch is scheduled for mid-2003, on an H-IIA Rocket Transfer Vehicle, out of the Tanegashima Space Center of Japan. Two identical facilities will be built. While one facility is onboard the ISS, the other is re-integrated on the ground with new experiments. When the cryogen of the facility in space are exhausted, it will be swapped with the other facility with the new experiment. A total of 20 science missions are envisioned over the next 20 years.

Holmes, Warren; Lai, Anthony; Croonquist, Arvid; Chui, Talso; Eraker, J. H.; Abbott, Randy; Mills, Gary; Mohl, James; Craig, James; Balachandra, Balu; Gannon, Jade

2000-01-01

110

The physics design of the Tokamak Physics Experiment  

NASA Astrophysics Data System (ADS)

The physics approaches to improved, steady-state tokamak reactors, as evolved through reactor design studies, ideas based on experimental results, and better theoretical understanding, are the foundation for the mission and physics design of the Tokamak Physics Experiment (TPX). The mission of TPX is to develop the scientific basis for cost-competitive, continuously operating tokamak power plants. We report here the design status of TPX, a device optimized to achieve improved performance through strong plasma shaping, recycling control, and current profile shaping, while operating continuously. The design incorporates poloidal field flexibility for a wide range of operation in normalized beta and internal inductance, a double-null 'Vee' divertor configuration for power and particle control, internal and external n (ne) 0 coils, as well as passive stabilizers, for control of MHD activity, and remote maintenance for continuous high-power operation in deuterium. Having superconducting poloidal and toroidal coils, the TPX device itself is capable of continuous operation, although initially auxiliary equipment limits the pulse length to 1000 sec.

Thomassen, K. I.; Batchelor, D. B.; Bialek, J.

1994-08-01

111

Integrated physics package of a chip-scale atomic clock  

NASA Astrophysics Data System (ADS)

The physics package of a chip-scale atomic clock (CSAC) has been successfully realized by integrating vertical cavity surface emitting laser (VCSEL), neutral density (ND) filter, ?/4 wave plate, 87Rb vapor cell, photodiode (PD), and magnetic coil into a cuboid metal package with a volume of about 2.8 cm3. In this physics package, the critical component, 87Rb vapor cell, is batch-fabricated based on MEMS technology and in-situ chemical reaction method. Pt heater and thermistors are integrated in the physics package. A PTFE pillar is used to support the optical elements in the physics package, in order to reduce the power dissipation. The optical absorption spectrum of 87Rb D1 line and the microwave frequency correction signal are successfully observed while connecting the package with the servo circuit system. Using the above mentioned packaging solution, a CSAC with short-term frequency stability of about 7 × 10-10 ?-1/2 has been successfully achieved, which demonstrates that this physics package would become one promising solution for the CSAC.

Li, Shao-Liang; Xu, Jing; Zhang, Zhi-Qiang; Zhao, Lu-Bing; Long, Liang; Wu, Ya-Ming

2014-07-01

112

Analysis of the physical atomic forces between noble gas atoms, alkali ions and halogen ions  

NASA Technical Reports Server (NTRS)

The physical forces between atoms and molecules are important in a number of processes of practical importance, including line broadening in radiative processes, gas and crystal properties, adhesion, and thin films. The components of the physical forces between noble gas atoms, alkali ions, and halogen ions are analyzed and a data base for the dispersion forces is developed from the literature based on evaluations with the harmonic oscillator dispersion model for higher order coefficients. The Zener model of the repulsive core is used in the context of the recent asymptotic wave functions of Handler and Smith; and an effective ionization potential within the Handler and Smith wave functions is defined to analyze the two body potential data of Waldman and Gordon, the alkali-halide molecular data, and the noble gas crystal and salt crystal data. A satisfactory global fit to this molecular and crystal data is then reproduced by the model to within several percent. Surface potentials are evaluated for noble gas atoms on noble gas and salt crystal surfaces with surface tension neglected. Within this context, the noble gas surface potentials on noble gas and salt crystals are considered to be accurate to within several percent.

Wilson, J. W.; Heinbockel, J. H.; Outlaw, R. A.

1986-01-01

113

Characterization of the Source Physics Experiment Site  

NASA Astrophysics Data System (ADS)

Designed to improve long-range treaty monitoring capabilities, the Source Physics Experiments, conducted at the Nevada National Security Site, also provide an opportunity to advance near-field monitoring and field-based investigations of suspected underground test locations. In particular, features associated with underground testing can be evaluated using Source Physics Experiment activities as analogs, linking on-site inspections with remote sensing technologies. Following a calibration shot (SPE 1), SPE 2 (10/2011) and SPE 3 (07/2012) were performed in the same emplacement hole with 1.0 ton of explosives at 150 ft depth. Because one of the goals of the Source Physics Experiments is to determine damage effects on seismic wave propagation and improve modeling capabilities, a key component in the predictive component and ultimate validation of the models is a full understanding of the intervening geology between the source and instrumented bore holes. Ground-based LIDAR and fracture mapping, mechanical properties determined via laboratory testing of rock core, discontinuity analysis and optical microscopy of the core rocks were performed prior to and following each experiment. In addition, gravity and magnetic data were collected between SPE 2 and 3. The source region of the explosions was also characterized using cross-borehole seismic tomography and vertical seismic profiling utilizing two sets of two boreholes within 40 meters of ground zero. The two sets of boreholes are co-linear with the explosives hole in two directions. Results of the LIDAR collects from both SPE 2 and 3 indicate a permanent ground displacement of up to several centimeters aligning along the projected surface traces of two faults observed in the core and fractures mapped at the surface. Laboratory testing and optical work show a difference in the characteristics of the rocks below and above 40 feet and within the fault zones.The estimated near-surface densities from the gravity survey show substantial changes in apparent near-surface density and may help explain independently-observed near-surface velocity changes. Work by Los Alamos National Laboratory was sponsored by the National Nuclear Security AdministrationAward No. DE-AC52-06NA25946/NST10-NCNS-PD00. Work by National Security Technologies, LLC, was performed under Contract No. DE AC52 06NA25946 with the U.S. Department of Energy. Sandia National Laboratories, is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Sussman, A. J.; Schultz-Fellenz, E. S.; Broome, S. T.; Townsend, M.; Abbott, R. E.; Snelson, C. M.; Cogbill, A. H.; Conklin, G.; Mitra, G.; Sabbeth, L.

2012-12-01

114

Atom optics and space physics: A summary of an 'Enrico Fermi' summer school  

NASA Astrophysics Data System (ADS)

We describe the scientific content of the International School of Physics 'Enrico Fermi' on atom optics and space physics, organized by the Italian Physical Society in Varenna at Lake Como, Italy, 2-13 July 2007.

Arimondo, Ennio; Ertmer, Wolfgang; Rasel, Ernst M.; Schleich, Wolfgang P.

2008-03-01

115

Atom optics and space physics: A summary of an 'Enrico Fermi' summer school  

Microsoft Academic Search

We describe the scientific content of the International School of Physics 'Enrico Fermi' on atom optics and space physics, organized by the Italian Physical Society in Varenna at Lake Como, Italy, 2-13 July 2007.

Ennio Arimondo; Wolfgang Ertmer; Ernst M. Rasel; Wolfgang P. Schleich

2008-01-01

116

Development of Spectral and Atomic Models for Diagnosing Energetic Particle Characteristics in Fast Ignition Experiments  

SciTech Connect

This Final Report summarizes work performed under DOE STTR Phase II Grant No. DE-FG02-05ER86258 during the project period from August 2006 to August 2009. The project, “Development of Spectral and Atomic Models for Diagnosing Energetic Particle Characteristics in Fast Ignition Experiments,” was led by Prism Computational Sciences (Madison, WI), and involved collaboration with subcontractors University of Nevada-Reno and Voss Scientific (Albuquerque, NM). In this project, we have: ? Developed and implemented a multi-dimensional, multi-frequency radiation transport model in the LSP hybrid fluid-PIC (particle-in-cell) code [1,2]. ? Updated the LSP code to support the use of accurate equation-of-state (EOS) tables generated by Prism’s PROPACEOS [3] code to compute more accurate temperatures in high energy density physics (HEDP) plasmas. ? Updated LSP to support the use of Prism’s multi-frequency opacity tables. ? Generated equation of state and opacity data for LSP simulations for several materials being used in plasma jet experimental studies. ? Developed and implemented parallel processing techniques for the radiation physics algorithms in LSP. ? Benchmarked the new radiation transport and radiation physics algorithms in LSP and compared simulation results with analytic solutions and results from numerical radiation-hydrodynamics calculations. ? Performed simulations using Prism radiation physics codes to address issues related to radiative cooling and ionization dynamics in plasma jet experiments. ? Performed simulations to study the effects of radiation transport and radiation losses due to electrode contaminants in plasma jet experiments. ? Updated the LSP code to generate output using NetCDF to provide a better, more flexible interface to SPECT3D [4] in order to post-process LSP output. ? Updated the SPECT3D code to better support the post-processing of large-scale 2-D and 3-D datasets generated by simulation codes such as LSP. ? Updated atomic physics modeling to provide for more comprehensive and accurate atomic databases that feed into the radiation physics modeling (spectral simulations and opacity tables). ? Developed polarization spectroscopy modeling techniques suitable for diagnosing energetic particle characteristics in HEDP experiments. A description of these items is provided in this report. The above efforts lay the groundwork for utilizing the LSP and SPECT3D codes in providing simulation support for DOE-sponsored HEDP experiments, such as plasma jet and fast ignition physics experiments. We believe that taken together, the LSP and SPECT3D codes have unique capabilities for advancing our understanding of the physics of these HEDP plasmas. Based on conversations early in this project with our DOE program manager, Dr. Francis Thio, our efforts emphasized developing radiation physics and atomic modeling capabilities that can be utilized in the LSP PIC code, and performing radiation physics studies for plasma jets. A relatively minor component focused on the development of methods to diagnose energetic particle characteristics in short-pulse laser experiments related to fast ignition physics. The period of performance for the grant was extended by one year to August 2009 with a one-year no-cost extension, at the request of subcontractor University of Nevada-Reno.

MacFarlane, Joseph J [Prism Computational Sciences] [Prism Computational Sciences

2009-08-07

117

The laboratory experience in introductory physics courses  

NASA Astrophysics Data System (ADS)

The last two decades or so have witnessed intense efforts to improve the teaching and learning of physics. Scholarly studies have provided the grounding for many projects which reform the structure of introductory courses. A number of these innovations, however, are resource intensive, or depend on the ability to introduce changes in areas which are beyond the control of the faculty (e.g., scheduling), thus inhibiting their implementation. An alternative strategy that overcomes these obstacles is to modify the nature of the laboratory experience (a component that practically nobody disputes is an essential part of the introductory course), to provide hands-on learning opportunities that differ from the traditional "follow-this-recipe-to-verify-this-law" approach. I have chosen to implement a variety of activities that support the overall objectives of the course: developing conceptual understanding and transferable skills, and providing practice in the ways scientists actually do science. Given the audience in this two-semester, algebra-based course, mostly biology majors and pre-professionals (health-related careers, such as medicine, physical therapy, and veterinary), these goals were identified as the most important and lasting contribution that a physics course can make to the students intellectual development. I offer here examples of the types of hands on activities that I have implemented, organized for the sake of this presentation in four rather loose categories, depending on which subset of the course objectives the activities mostly address: self-designed lab activities, discussion of demo-type activities, building concepts from simple to complex, and out-of-lab physical phenomena.

Di Stefano, Maria C.

1997-03-01

118

Versatile cold atom source for multi-species experiments  

NASA Astrophysics Data System (ADS)

We present a dual-species oven and Zeeman slower setup capable of producing slow, high-flux atomic beams for loading magneto-optical traps. Our compact and versatile system is based on electronic switching between different magnetic field profiles and is applicable to a wide range of multi-species experiments. We give details of the vacuum setup, coils, and simple electronic circuitry. In addition, we demonstrate the performance of our system by optimized, sequential loading of magneto-optical traps of lithium-6 and cesium-133.

Paris-Mandoki, A.; Jones, M. D.; Nute, J.; Wu, J.; Warriar, S.; Hackermüller, L.

2014-11-01

119

Soft physics results from the PHENIX experiment  

NASA Astrophysics Data System (ADS)

High-energy heavy-ion collisions at RHIC-BNL and LHC-CERN provide a unique opportunity to study the properties of the high-temperature and high-density nuclear matter called the quark-gluon plasma (QGP), which is supposed to exist in the early universe or inside neutron stars. The PHENIX experiment is one of the major experiments at RHIC to study the properties of QGP, especially focusing on various particle identification capabilities including photons, leptons, and hadrons. This article summarizes the soft physics results from the PHENIX experiment, such as (1) global properties like transverse energy and multiplicity measurements as well as centrality determination, (2) transverse momentum distribution and the nuclear modification factor, which represents the modification of the spectra in A+A collisions relative to the binary-collision-scaled superposition of p+p data, (3) space-time properties with Hanbury Brown and Twiss (HBT) interferometry correlation measurement and source imaging, (4) elliptic collective expansion and higher-order harmonic event anisotropy, and (5) di-hadron correlation, jet modification, and medium response known as jet-quenching from the partonic energy loss and redistribution of the lost energy. These results are reviewed and discussed.

Esumi, ShinIchi

2015-03-01

120

Further investigations of experiment A0034 atomic oxygen stimulated outgassing  

NASA Technical Reports Server (NTRS)

Thermal control coatings within the recessed compartments of LDEF Experiment A0034 experienced the maximum leading edge fluence of atomic oxygen with considerably less solar UV radiation exposure than top-surface mounted materials of other LDEF experiments on either the leading or the trailing edge. This combination of exposure within A0034 resulted in generally lower levels of darkening attributable to solar UV radiation than for similar materials on other LDEF experiments exposed to greater cumulative solar UV radiation levels. Changes in solar absorptance and infrared thermal emittance of the exposed coatings are thus unique to this exposure. Analytical results for other applications have been found for environmentally induced changes in fluorescence, surface morphology, light scattering, and the effects of coating outgassing products on adjacent mirrors and windows of the A0034 experiment. Some atmospheric bleaching of the thermal control coatings, in addition to that presumably experience during reentry and recovery operations, has been found since initial post-flight observations and measurements.

Linton, Roger C.; Finckenor, Miria M.; Kamenetzky, Rachel R.

1995-01-01

121

AGS experiments in nuclear/QCD physics at medium energies  

SciTech Connect

This report contains a diagram of the experimental setup for each experiment as well as giving a brief discussion of its purpose and list of collaborators for the experiment. Thirty-one experiments in the areas of nuclear physics and particle physics are covered. It concludes with a list of publications of the AGS experiments.

Lo Presti, P.

1998-07-01

122

Physics Experiments That You Can Do at Home  

E-print Network

Physics Experiments That You Can Do at Home Brought to you by The Wonders of Physics University of Wisconsin ­ Madison #12;2 The Wonders of Physics The Wonders of Physics is an outreach program sponsored by the Physics Department at the University of Wisconsin-Madison. Professor Clint Sprott has been amazing

Saffman, Mark

123

PHYSICAL REVIEW A 86, 053401 (2012) Electric-field sensing near the surface microstructure of an atom chip using cold Rydberg atoms  

E-print Network

of an atom chip using cold Rydberg atoms J. D. Carter, O. Cherry, and J. D. D. Martin Department of Physics fields near the heterogeneous metal-dielectric surface of an atom chip were measured using cold atoms. The atomic sensitivity to electric fields was enhanced by exciting the atoms to Rydberg states that are 108

Le Roy, Robert J.

124

Skylab experiments. Volume 1: Physical science, solar astronomy  

NASA Technical Reports Server (NTRS)

The basic subject of this volume is the solar astronomy program conducted on Skylab. In addition to descriptions of the individual experiments and the principles involved in their performance, a brief description is included of the sun and the energy characteristics associated with each zone. Wherever possible, related classroom activities have been identified and discussed in some detail. It will be apparent that the relationships rest not only in the field of solar astronomy, but also in the following subjects: (1) physics - optics, electromagnetic spectrum, atomic structure, etc.; (2) chemistry - emission spectra, kinetic theory, X-ray absorption, etc.; (3) biology - radiation and dependence on the sun; (4) electronics - cathode ray tubes, detectors, photomultipliers, etc.; (5) photography; (6) astronomy; and (7) industrial arts.

1973-01-01

125

Strangeness nuclear physics experiments at J-PARC  

NASA Astrophysics Data System (ADS)

Experimental plans for strangeness nuclear physics at the J-PARC hadron facility are summarized. High-intensity K- beams of ˜2 GeV/c available at the K1.8 beam line will open a new era in the studies of double strangeness nuclear systems. Spectroscopy of ? hypernuclei, the study of ?? hypernuclei, and measurement of ?-atomic X-rays are planned to reveal baryon-baryon interactions with S (strangeness) = -2 systems. In addition, ?-ray spectroscopy of ? hypernuclei, spectroscopy of neutron-rich ? hypernuclei, the study of weak decays of ? hypernuclei, and hyperon-nucleon scattering experiments, which are planned to be performed at the K1.8 and K1.1 beam lines, will clarify the details of S = -1 baryon-baryon interactions as well as the nuclear medium effects on baryon properties. A future plan to extend the hadron hall is also described.

Tamura, H.

2012-12-01

126

Tokamak Physics Experiment diagnostic plans (invited)  

NASA Astrophysics Data System (ADS)

A superconducting Tokamak Physics Experiment (TPX) whose mission is to develop the scientific basis for a compact and continuously operating tokamak fusion reactor is being designed by an integrated U.S. national team. Key physics features such as strong shaping, a double-null poloidal divertor, full noninductive current drive, and current profile control capability will be used to explore improvements in energy confinement and beta limit scaling in high-aspect-ratio plasmas with a high bootstrap current fraction. Steady-state operation of TPX permits these studies to be extended to time scales significantly exceeding the global current-relaxation time and the plasma-wall equilibrium time. The diagnostic requirements are determined by the TPX mission and supporting objectives, such as optimization of plasma performance through active control of the current profile and of the plasma-wall interactions. Diagnostic measurements are needed to characterize the plasma behavior over the full range of conventional tokamak plasma parameters with appropriate spatial and temporal resolution as well as for control and monitoring of aspects of the machine operation such as the plasma position and shape, plasma current, vacuum vessel currents, electron density and temperature, and the divertor and limiter temperatures. In addition, several diagnostic capabilities that are especially critical for the TPX project will be discussed.

Medley, S. S.

1995-01-01

127

A Data Readout Approach for Physics Experiment  

E-print Network

With the increasing physical event rate and number of electronic channels, traditional readout scheme meets the challenge of improving readout speed caused by the limited bandwidth of crate backplane. In this paper, a high-speed data readout method based on Ethernet is designed for each module to have capability of transmitting data to DAQ. Features of explicitly parallel data transmitting and distributed network architecture make the readout system has advantage of adapting varying requirements of particle physics experiments. Furthermore, to guarantee the readout performance and flexibility, a standalone embedded CPU system is utilized for network protocol stack processing. To receive customized data format and protocol from front-end electronics, a field programmable gate array (FPGA) is used for logic reconfiguration. To optimize the interface and improve the data swap speed between CPU and FPGA, a sophisticated method based on SRAM is presented in this paper. For the purpose of evaluating this high-speed readout method, a simplified readout module is designed and implemented. Test results show that this module can support up to 70Mbps data throughput from the readout module to DAQ smoothly.

Huang Xi-Ru; Cao Ping; Gao Li-Wei; Zheng Jia-Jun

2014-10-21

128

Atom Interferometers  

E-print Network

Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic clocks. Atom interferometry is now reaching maturity as a powerful art with many applications in modern science. In this review we first describe the basic tools for coherent atom optics including diffraction by nanostructures and laser light, three-grating interferometers, and double wells on AtomChips. Then we review scientific advances in a broad range of fields that have resulted from the application of atom interferometers. These are grouped in three categories: (1) fundamental quantum science, (2) precision metrology and (3) atomic and molecular physics. Although some experiments with Bose Einstein condensates are included, the focus of the review is on linear matter wave optics, i.e. phenomena where each single atom interferes with itself.

Alexander D. Cronin; Joerg Schmiedmayer; David E. Pritchard

2007-12-21

129

Probing physical properties at the nanoscale using atomic force microscopy  

NASA Astrophysics Data System (ADS)

Techniques that measure physical properties at the nanoscale with high sensitivity are significantly limited considering the number of new nanomaterials being developed. The development of atomic force microscopy (AFM) has lead to significant advancements in the ability to characterize physical properties of materials in all areas of science: chemistry, physics, engineering, and biology have made great scientific strides do to the versatility of the AFM. AFM is used for quantification of many physical properties such as morphology, electrical, mechanical, magnetic, electrochemical, binding interactions, and protein folding. This work examines the electrical and mechanical properties of materials applicable to the field of nano-electronics. As electronic devices are miniaturized the demand for materials with unique electrical properties, which can be developed and exploited, has increased. For example, discussed in this work, a derivative of tetrathiafulvalene, which exhibits a unique loss of conductivity upon compression of the self-assembled monolayer could be developed into a molecular switch. This work also compares tunable organic (tetraphenylethylene tetracarboxylic acid and bis(pyridine)s assemblies) and metal-organic (Silver-stilbizole coordination compounds) crystals which show high electrical conductivity. The electrical properties of these materials vary depending on their composition allowing for the development of compositionally tunable functional materials. Additional work was done to investigate the effects of molecular environment on redox active 11-ferroceneyl-1 undecanethiol (Fc) molecules. The redox process of mixed monolayers of Fc and decanethiol was measured using conductive probe atomic force microscopy and force spectroscopy. As the concentration of Fc increased large, variations in the force were observed. Using these variations the number of oxidized molecules in the monolayer was determined. AFM is additionally capable of investigating interactions at the nanoscale, such as ligand-receptor interactions. This work examines the interactions between the enzyme dihydrofolate reductase (DHFR), a widely investigated enzyme targeted for cancer and antimicrobial pharmaceutical, and methotrexate (MTX), a strong competitive inhibitor of DHFR. The DHFR was immobilized on a gold substrate, bound through a single surface cysteine, and maintained catalytic activity. AFM probe was functionalized with MTX and the interaction strength was measured using AFM. This work highlights the versatility of AFM, specifically force spectroscopy for the quantification of electrical, mechanical, and ligand-receptor interactions at the nanoscale.

Ditzler, Lindsay Rachel

130

Primer on Detectors and Electronics for Particle Physics Experiments  

E-print Network

1 Primer on Detectors and Electronics for Particle Physics Experiments Alexander A. Grillo Santa Cruz Institute for Particle Physics University of California Santa Cruz 19-Jul-14 Abstract This primer the primer itself. I Background of Particle Physics Scattering Experiments Physicists have made the most

California at Santa Cruz, University of

131

The Nuclear Physics of Hyperfine Structure in Hydrogenic Atoms  

E-print Network

The theory of QED corrections to hyperfine structure in light hydrogenic atoms and ions has recently advanced to the point that the uncertainty of these corrections is much smaller than 1 part per million (ppm), while the experiments are even more accurate. The difference of the experimental results and the corresponding QED theory is due to nuclear effects, which are primarily the result of the finite nuclear charge and magnetization distributions. This difference varies from tens to hundreds of ppm. We have calculated the dominant nuclear component of the 1s hyperfine interval for deuterium, tritium and singly ionized helium, using a unified approach with modern second-generation potentials. The calculated nuclear corrections are within 3% of the experimental values for deuterium and tritium, but are roughly 20% discrepant for helium. The nuclear corrections for the trinucleon systems can be qualitatively understood by invoking SU(4) symmetry.

J. L. Friar; G. L. Payne

2005-02-01

132

Hadron Physics at the COMPASS Experiment  

E-print Network

Quantum Chromodynamics (QCD), the theory of strong interactions, in principle describes the interaction of quark and gluon fields. However, due to the self-coupling of the gluons, quarks and gluons are confined into hadrons and cannot exist as free particles. The quantitative understanding of this confinement phenomenon, which is responsible for about 98\\% of the mass of the visible universe, is one of the major open questions in particle physics. The measurement of the excitation spectrum of hadrons and of their properties gives valuable input to theory and phenomenology. In the Constituent Quark Model (CQM) two types of hadrons exist: mesons, made out of a quark and an antiquark, and baryons, which consist of three quarks. But more advanced QCD-inspired models and Lattice QCD calculations predict the existence of hadrons with exotic properties interpreted as excited glue (hybrids) or even pure gluonic bound states (glueballs). The COMPASS experiment at the CERN Super Proton Synchrotron has acquired large data sets, which allow to study light-quark meson and baryon spectra in unprecedented detail. The presented overview of the first results from this data set focuses in particular on the light meson sector and presents a detailed analysis of three-pion final states. A new $J^{PC} = 1^{++}$ state, the $a_1(1420)$, is observed with a mass and width in the ranges $m = 1412-1422\\,\\mathrm{MeV}/c^2$ and $\\Gamma = 130-150\\,\\mathrm{MeV}/c^2$.

Fabian Krinner; for the COMPASS collaboration

2014-12-08

133

Laboratory plasma physics experiments using merging supersonic plasma jets  

E-print Network

We describe a laboratory plasma physics experiment at Los Alamos National Laboratory that uses two merging supersonic plasma jets formed and launched by pulsed-power-driven rail guns. The jets can be formed using any atomic species or mixture available in a compressed-gas bottle and have the following nominal initial parameters at the railgun nozzle exit: $n_e\\approx n_i \\sim 10^{16}$ cm$^{-3}$, $T_e \\approx T_i \\approx 1.4$ eV, $V_{\\rm jet}\\approx 30$-100 km/s, mean charge $\\bar{Z}\\approx 1$, sonic Mach number $M_s\\equiv V_{\\rm jet}/C_s>10$, jet diameter $=5$ cm, and jet length $\\approx 20$ cm. Experiments to date have focused on the study of merging-jet dynamics and the shocks that form as a result of the interaction, in both collisional and collisionless regimes with respect to the inter-jet classical ion mean free path, and with and without an applied magnetic field. However, many other studies are also possible, as discussed in this paper.

Hsu, S C; Merritt, E C; Adams, C S; Dunn, J P; Brockington, S; Case, A; Gilmore, M; Lynn, A G; Messer, S J; Witherspoon, F D

2014-01-01

134

PHYSICAL REVIEW A 86, 053630 (2012) Classical rotons in cold atomic traps  

E-print Network

PHYSICAL REVIEW A 86, 053630 (2012) Classical rotons in cold atomic traps H. Terc¸as,1,2,* J. T of a roton minimum in the dispersion relation of elementary excitations in cold atomic gases in the presence is responsible for a stochastic short-range force acting on the atoms. We show that the dynamical competition

Guerra, Vasco

135

Physical methods in nanoscale science with the atomic force microscope  

NASA Astrophysics Data System (ADS)

The atomic force microscope (AFM) has opened up a wide gate to the nanoscopic world. Since its invention twelve years ago, it has allowed researchers to advance to new science. The extent of this advancement is strongly coupled to the sophistication of AFM instrumentation and to the methods with which AFMs are used. New AFMs and methods are needed to push the limits. Chapter 1 and 2 introduce such new AFMs with low-noise and high-speed characteristics. The AFM presented in Chapter 2 has a focused spot size of 1.6 m m in diameter and is capable of using cantilevers much smaller than previously possible. Chapter 3 discusses the physics of the detection system and gives methods for improving the detection sensitivity. Thermal motion of the cantilever, usually contributing to the noise in a measurement, is a method for probing the oscillatory hydration potential at a calcite-water interface in Chapter 4. Chapter 5 establishes a method of measuring the three-dimensional electromagnetic field over a surface and comparing the data to micro-magnetic models. Biomineralization of marine abalone nacre is the subject of interdisciplinary Chapter 6, where a variety of microscopic and statistical methods distinguish between two competing models of nacre growth.

Schaffer, Tilman Erich

1998-12-01

136

The physics of SU(4) alkaline-earth-atom-based Kondo lattice model at the Toulouse point  

NASA Astrophysics Data System (ADS)

The study of ultracold alkaline-earth atoms has gained significant attention due largely to recent efforts to employ ultracold alkaline-earth atoms as a unique platform to explore quantum computing and many-body physics. For alkaline-earth atoms, there is an almost perfect decoupling of the nuclear spin from the electronic angular momentum in both the ground and the metastable states. This along with the existence of relatively high nuclear spin degrees of freedom makes the cold alkaline-earth atoms an excellent candidate that one can employ to study Kondo effects with higher SU(N) spin degrees of freedom. In this work, we focus on a mixture of two-component fermionic alkaline-earth atoms loaded in external optical lattice potentials and treat it as an cold atom implementation of SU(4) Kondo lattice model. We apply bosonization and canonical transformation to obtain an exactly solvable point (the so-called Toulouse point). We study the physics of the system at the Toulouse point by calculating various correlation functions in the parameter regimes that are experimentally accessible to cold atom experiments. This work is supported by the US National Science Foundation and the US Army Research Office.

Duki, Solomon F.; Ling, Hong

2013-03-01

137

Impact Crater Experiments for Introductory Physics and Astronomy Laboratories  

ERIC Educational Resources Information Center

Activity-based collisional analysis is developed for introductory physics and astronomy laboratory experiments. Crushable floral foam is used to investigate the physics of projectiles undergoing completely inelastic collisions with a low-density solid forming impact craters. Simple drop experiments enable determination of the average acceleration,…

Claycomb, J. R.

2009-01-01

138

New experiments on few-electron very heavy atoms  

SciTech Connect

New experiments, to test quantum electrodynamics (QED) in strong Coulomb fields and to study atomic collisions at ultrarelativistic energies, are proposed. A 0.1% measurement of the 2/sup 2/P/sub 1/2/-2/sup 2/S/sub 1/2/ splitting in lithium like uranium (Z=92) and the 2/sup 3/P/sub 0/ - 2/sup 3/S/sub 1/ splitting in heliumlike uranium is proposed as a sub 1% test of the Lamb shift in a strong Coulomb field. Measurements of the hyperfine splitting of hydrogenlike thallium (Z=81) and the g/sub j/ factor of the ground state of hydrogenlike uranium are propsed as a test of the QED contribution to the magnetic moment of an electron bound in a strong Coulomb field. Measurements of capture cross sections for ultra relativistic very heavy nuclei are proposed to look for the capture of electrons from pair production. 40 refs., 7 figs., 2 tabs.

Gould, H.

1985-07-01

139

Youth with Visual Impairments: Experiences in General Physical Education  

ERIC Educational Resources Information Center

The rapid increase in the number of students with visual impairments currently being educated in inclusive general physical education makes it important that physical education instructors know how best to serve them. Assessment of the experiences of students with visual impairments during general physical education classes, knowledge of students'…

Lieberman, Lauren J.; Robinson, Barbara L.; Rollheiser, Heidi

2006-01-01

140

Current experiments in elementary particle physics, revision 1-85  

NASA Astrophysics Data System (ADS)

This report contains summaries of 551 approved experiments in elementary particle physics (experiments that finished taking data before 1 January 1980 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Moscow Institute of Theoretical and Experimental Physics, Tokyo Institute of Nuclear studies, KEK, LAMPF, Leningrad Nuclear Physics Institute, Saclay, Serpukhov, SIN, SLAC, and TRIUMF, and also experiments on proton decay. Properties of the fixed-target beams at most of the laboratories are summarized. Instructions are given for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

Wohl, C. G.; Armstrong, F. E.; Rittenberg, A.; Trippe, T. G.; Yost, G. P.; Oyanagi, Y.; Dodder, D. C.; Grudtsin, S. N.; Ryabov, Y. G.; Frosch, R.

1985-01-01

141

Current experiments in elementary particle physics. Revision 1-85  

SciTech Connect

This report contains summaries of 551 approved experiments in elementary particle physics (experiments that finished taking data before 1 January 1980 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Moscow Institute of Theoretical and Experimental Physics, Tokyo Institute of Nuclear Studies, KEK, LAMPF, Leningrad Nuclear Physics Institute, Saclay, Serpukhov, SIN, SLAC, and TRIUMF, and also experiments on proton decay. Properties of the fixed-target beams at most of the laboratories are summarized. Instructions are given for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

Wohl, C.G.; Armstrong, F.E.; Rittenberg, A.; Trippe, T.G.; Yost, G.P.; Oyanagi, Y.; Dodder, D.C.; Grudtsin, S.N.; Ryabov, Yu.G.; Frosch, R.

1985-01-01

142

Atom-resolved electronic spectra for Alq3 from theory and experiment A. Curionia)  

E-print Network

Atom-resolved electronic spectra for Alq3 from theory and experiment A. Curionia) and W. Andreoni from the different atoms and molecular orbitals. Fingerprints of the molecular bonding and of the individual atoms are identified. These results are meant to be a reference for the monitoring of chemical

Himpsel, Franz J.

143

Determination of Spin-Lattice Relaxation of Time Using (Super 13)C NMR: An Undergraduate Physical Chemistry Laboratory Experiment  

ERIC Educational Resources Information Center

An experiment designed for the physical chemistry laboratory where (super 13)C NMR is applied to determine the spin-lattice relaxation time for carbon atoms in n-hexanol is proposed. It is concluded that students learn the principles and concepts of NMR spectroscopy as well as dynamic NMR experiments.

Gasyna, Zbigniew L.; Jurkiewicz, Antoni

2004-01-01

144

Fisher-like atomic divergences: Mathematical grounds and physical applications  

NASA Astrophysics Data System (ADS)

Two different local divergence measures, the Fisher (FD) and the Jensen-Fisher (JFD) ones, are compared in this work by applying them to atomic one-particle densities in position and momentum spaces. They are defined in terms of the absolute and the relative Fisher information functionals. The analysis here afforded includes not only neutral atoms, but also singly-charged cations. The results are interpreted and justified according to (i) shell-filling patterns, (ii) short- and long-range behaviors of the atomic densities, and (iii) the value of the atomic ionization potential. The strengths of the FD measure, as compared to the JFD one, are emphasized.

Martín, A. L.; Angulo, J. C.; Antolín, J.

2013-11-01

145

Atom chip apparatus for experiments with ultracold rubidium and potassium gases  

SciTech Connect

We present a dual chamber atom chip apparatus for generating ultracold {sup 87}Rb and {sup 39}K atomic gases. The apparatus produces quasi-pure Bose-Einstein condensates of 10{sup 4} {sup 87}Rb atoms in an atom chip trap that features a dimple and good optical access. We have also demonstrated production of ultracold {sup 39}K and subsequent loading into the chip trap. We describe the details of the dual chamber vacuum system, the cooling lasers, the magnetic trap, the multicoil magnetic transport system, the atom chip, and two optical dipole traps. Due in part to the use of light-induced atom desorption, the laser cooling chamber features a sufficiently good vacuum to also support optical dipole trap-based experiments. The apparatus is well suited for studies of atom-surface forces, quantum pumping and transport experiments, atom interferometry, novel chip-based traps, and studies of one-dimensional many-body systems.

Ivory, M. K.; Ziltz, A. R.; Fancher, C. T.; Pyle, A. J.; Sensharma, A.; Chase, B.; Field, J. P.; Garcia, A.; Aubin, S., E-mail: saaubi@wm.edu [Department of Physics, College of William and Mary, Williamsburg, Virginia 23187 (United States); Jervis, D. [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)] [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)

2014-04-15

146

Atom chip apparatus for experiments with ultracold rubidium and potassium gases.  

PubMed

We present a dual chamber atom chip apparatus for generating ultracold (87)Rb and (39)K atomic gases. The apparatus produces quasi-pure Bose-Einstein condensates of 10(4) (87)Rb atoms in an atom chip trap that features a dimple and good optical access. We have also demonstrated production of ultracold (39)K and subsequent loading into the chip trap. We describe the details of the dual chamber vacuum system, the cooling lasers, the magnetic trap, the multicoil magnetic transport system, the atom chip, and two optical dipole traps. Due in part to the use of light-induced atom desorption, the laser cooling chamber features a sufficiently good vacuum to also support optical dipole trap-based experiments. The apparatus is well suited for studies of atom-surface forces, quantum pumping and transport experiments, atom interferometry, novel chip-based traps, and studies of one-dimensional many-body systems. PMID:24784588

Ivory, M K; Ziltz, A R; Fancher, C T; Pyle, A J; Sensharma, A; Chase, B; Field, J P; Garcia, A; Jervis, D; Aubin, S

2014-04-01

147

Review of controlled laboratory experiments on physics of magnetic reconnection  

E-print Network

Review of controlled laboratory experiments on physics of magnetic reconnection Masaaki Yamada from the most recent experiments in the past 2 decades in which magnetic reconnection has been of the reconnection process and its hydromagnetic consequences has been largely theoretical. Laboratory experiments

148

Nuclear Physics Experiments Below The Coulomb Barrier  

SciTech Connect

In 1932, Cockcroft and Walton showed that (p,{alpha}) reactions with lithium were possible at energies near 100 keV. We report an undergraduate laboratory experiment with 90 keV protons colliding with a thick lithium target. The experiment allows students to observe the products of two reactions, to determine the product masses, and to learn techniques for deconvolving experimental spectra profiles.

Sanders, J. M.; Clark, R. K. [Department of Physics, ILB 115, University of South Alabama, Mobile, AL, 36608 (United States); Cifuentes, J. R. Morales [Department of Physics, ILB 115, University of South Alabama, Mobile, AL, 36608 (United States); Department of Physics, University of Maryland, College Park, MD, 20742 (United States)

2011-06-01

149

The physical interest in kaonic- and antiprotonic-deuterium atoms  

E-print Network

Exotic deuterium and helium are discussed. The S, P and D levels of antiprotonic and kaonic atoms are calculated. Absorptive, subthreshold antiproton-nucleon amplitudes are extracted from experimental data and compared to model calculations. The existence of a quasi-bound state in the antiproton-nucleon system is indicated. In the kaonic atoms some effects of the Sigma(1385) resonance are evaluated.

S. Wycech; B. Loiseau

2005-08-05

150

Theoretical Atomic Physics code development II: ACE: Another collisional excitation code  

SciTech Connect

A new computer code for calculating collisional excitation data (collision strengths or cross sections) using a variety of models is described. The code uses data generated by the Cowan Atomic Structure code or CATS for the atomic structure. Collisional data are placed on a random access file and can be displayed in a variety of formats using the Theoretical Atomic Physics Code or TAPS. All of these codes are part of the Theoretical Atomic Physics code development effort at Los Alamos. 15 refs., 10 figs., 1 tab.

Clark, R.E.H.; Abdallah, J. Jr.; Csanak, G.; Mann, J.B.; Cowan, R.D.

1988-12-01

151

Physics of Hard Spheres Experiment: Significant and Quantitative Findings Made  

NASA Technical Reports Server (NTRS)

Direct examination of atomic interactions is difficult. One powerful approach to visualizing atomic interactions is to study near-index-matched colloidal dispersions of microscopic plastic spheres, which can be probed by visible light. Such spheres interact through hydrodynamic and Brownian forces, but they feel no direct force before an infinite repulsion at contact. Through the microgravity flight of the Physics of Hard Spheres Experiment (PHaSE), researchers have sought a more complete understanding of the entropically driven disorder-order transition in hard-sphere colloidal dispersions. The experiment was conceived by Professors Paul M. Chaikin and William B. Russel of Princeton University. Microgravity was required because, on Earth, index-matched colloidal dispersions often cannot be density matched, resulting in significant settling over the crystallization period. This settling makes them a poor model of the equilibrium atomic system, where the effect of gravity is truly negligible. For this purpose, a customized light-scattering instrument was designed, built, and flown by the NASA Glenn Research Center at Lewis Field on the space shuttle (shuttle missions STS 83 and STS 94). This instrument performed both static and dynamic light scattering, with sample oscillation for determining rheological properties. Scattered light from a 532- nm laser was recorded either by a 10-bit charge-coupled discharge (CCD) camera from a concentric screen covering angles of 0 to 60 or by sensitive avalanche photodiode detectors, which convert the photons into binary data from which two correlators compute autocorrelation functions. The sample cell was driven by a direct-current servomotor to allow sinusoidal oscillation for the measurement of rheological properties. Significant microgravity research findings include the observation of beautiful dendritic crystals, the crystallization of a "glassy phase" sample in microgravity that did not crystallize for over 1 year in 1g (Earth's gravity), and the emergence of face-centered-cubic (FCC) crystals late in the coarsening process (as small crystallites lost particles to the slow ripening of large crystallites). Significant quantitative findings from the microgravity experiments have been developed describing complex interactions among crystallites during the growth process, as concentration fields overlap in the surrounding disordered phase. Time-resolved Bragg scattering under microgravity captures one effect of these interactions quite conclusively for the sample at a volume fraction of 0.528. From the earliest time until the sample is almost fully crystalline, the size and overall crystallinity grow monotonically, but the number of crystallites per unit volume (number density) falls. Apparently nucleation is slower than the loss of crystallites because of the transfer of particles from small to large crystals. Thus, coarsening occurs simultaneously with growth, rather than following the completion of nucleation and growth as is generally assumed. In the same sample, an interesting signature appears in the apparent number density of crystallites and the volume fraction within the crystallites shortly before full crystallinity is reached. A brief upturn in both indicates the creation of more domains of the size of the average crystallite simultaneous with the compression of the crystallites. Only the emergence of dendritic arms offers a reasonable explanation. The arms would be "seen" by the light scattering as separate domains whose smaller radii of curvature would compress the interior phase. In fiscal year 1999, numerous papers, a doctoral dissertation, and the PHaSE final report were produced. Although this flight project has been completed, plans are in place for a follow-on colloid experiment by Chaikin and Russel that employs a light microscope within Glenn's Fluids and Combustion Facility on the International Space Station. PHaSE is providing us with a deeper understanding of the nure of phase transitions. The knowledge derived has added to the understandin

Doherty, Michael P.

2000-01-01

152

Characterizing Student Experiences in Physics Competitions: The Power of Emotions  

NASA Astrophysics Data System (ADS)

Low enrolment and motivation are key issues in physics education and recently the affective dimension of learning is being studied for evidence of its influence on student attitudes towards physics. Physics Olympics competitions are a novel context for stimulating intense emotional experiences. In this study, one team of students and their teacher were interviewed and observed prior to and during the event to characterize their emotions and determine the connections between their experiences and learning and attitudes/motivation towards physics. Results showed that certain types of events stimulated strong emotions of frustration and ownership, and that students’ attitudes were that physics is fun, diverse and relevant. Analysis of these themes indicated that the nature of emotions generated was connected to their attitudes towards physics. This finding points to the potential and value of informal and novel contexts in creating strong positive emotions, which have a strong influence on student attitudes towards physics.

Moll, Rachel F.; Nashon, S.; Anderson, D.

2006-12-01

153

Pre-Service Physics Teachers' Ideas on Size, Visibility and Structure of the Atom  

ERIC Educational Resources Information Center

Understanding the atom gives the opportunity to both understand and conceptually unify the various domains of science, such as physics, chemistry, biology, astronomy and geology. Among these disciplines, physics teachers are expected to be particularly well educated in this topic. It is important that pre-service physics teachers know what sort of…

Unlu, Pervin

2010-01-01

154

LOW-POWER PHYSICS EXPERIMENTS ON THE SODIUM REACTOR EXPERIMENT  

Microsoft Academic Search

A series of experiments was performed during the loading and low-power ; operation of the SRE to determine some of the more basic nuclear characteristics. ; Critical masses were dctermined and found to be 22.2 fuel elements, or 42.4 kg of ; uranlum-235, for the dry reactor (no sodium present), and 32.6 fuel elements or ; 62.2 kg of uranium-235,

1959-01-01

155

Students' Experiences of Understanding University Physics.  

ERIC Educational Resources Information Center

Previous research in the field of student learning in higher education has mostly focused on conceptual issues of students at the individual concept or task level. There has been little research of students' conceptions of whole subjects, and virtually no previous research of students' feelings of their conceptual experiences. This paper aims to…

Waterhouse, Fiona; Prosser, Michael

156

Exploring many-body physics with ultracold atoms  

NASA Astrophysics Data System (ADS)

The emergence of many-body physical phenomena from the quantum mechanical properties of atoms can be studied using ultracold alkali gases. The ability to manipulate both Bose-Einstein condensates (BECs) and degenerate Fermi gases (DFGs) with designer potential energy landscapes, variable interaction strengths and out-of-equilibrium initial conditions provides the opportunity to investigate collective behaviour under diverse conditions. With an appropriately chosen wavelength, optical standing waves provide a lattice potential for one target species while ignoring another spectator species. A "tune-in" scheme provides an especially strong potential for the target and works best for Li-Na, Li-K, and K-Na mixtures, while a "tune-out" scheme zeros the potential for the spectator, and is preferred for Li-Cs, K-Rb, Rb-Cs, K-Cs, and 39K-40K mixtures. Species-selective lattices provide unique environments for studying many-body behaviour by allowing for a phonon-like background, providing for effective mass tuning, and presenting opportunities for increasing the phase-space density of one species. Ferromagnetism is manifest in a two-component DFG when the energetically preferred many-body configuration segregates components. Within the local density approximation (LDA), the characteristic energies and the three-body loss rate of the system all give an observable signature of the crossover to this ferromagnetic state in a trapped DFG when interactions are increased beyond kFa(0) = 1:84. Numerical simulations of an extension to the LDA that account for magnetization gradients show that a hedgehog spin texture emerges as the lowest energy configuration in the ferromagnetic regime. Explorations of strong interactions in 40K constitute the first steps towards the realization of ferromagnetism in a trapped 40K gas. The many-body dynamics of a 87Rb BEC in a double well potential are driven by spatial phase gradients and depend on the character of the junction. The amplitude and frequency characteristics of the transport across a tunable barrier show a crossover between two paradigms of super uidity: Josephson plasma oscillations emerge for high barriers, where transport is via tunnelling, while hydrodynamic behaviour dominates for lower barriers. The phase dependence of the many-body dynamics is also evident in the observation of macroscopic quantum self trapping. Gross-Pitaevskii calculations facilitate the interpretation of system dynamics, but do not describe the observed damping.

LeBlanc, Lindsay Jane

157

Current experiments in elementary-particle physics - March 1983  

SciTech Connect

Microfiche are included which contain summaries of 479 experiments in elementary particle physics. Experiments are included at the following laboratories: Brookhaven (BNL); CERN; CESR; DESY; Fermilab (FNAL); Institute for Nuclear Studies (INS); KEK; LAMPF; Serpukhov (SERP); SIN; SLAC; and TRIUMF. Also, summaries of proton decay experiments are included. A list of experiments and titles is included; and a beam-target-momentum index and a spokesperson index are given. Properties of beams at the facilities are tabulated. (WHK)

Wohl, C.G.; Armstrong, F.E.; Rittenberg, A.

1983-03-01

158

Quantum metrology -- optical atomic clocks and many-body physics.  

NASA Astrophysics Data System (ADS)

Optical clocks based on atoms confined in optical lattices provide a unique opportunity for precise study and measurement of quantum many- body systems. The state-of-the-art optical lattice clock has reached an overall fractional frequency uncertainty of 1 x 10-16 [1]. One dominant contribution to this uncertainty is clock frequency shift arising from atomic collisions. Collisions between initially identical fermionic Sr atoms can occur when they are subject to slightly inhomogeneous optical excitations during the clock operation [2]. We have recently implemented a seemingly paradoxical solution to the collisionshift problem: with a strong atomic confinement in one-dimensional tube-shaped optical traps, we dramatically increase the atomic interactions. Instead of a naively expected increase of collisional frequency shifts, these shifts are increasingly suppressed [3]. The large atomic interaction strength creates an effective energy gap in the system such that inhomogeneous excitations can no longer drive fermions into a pseudo-spin antisymmetric state, and hence their collisions and the corresponding frequency shifts are suppressed. We demonstrate the effectiveness of this approach by reducing the density-related frequency shift to the level of 10-17, representing more than a factor of ten reduction from the previous record [1, 2]. In addition, we have observed well-resolved interaction sidebands separated from the main peak of the clock transition, giving a direct evidence for the removal of the interaction energy from the clock carrier transition. Control of atomic interactions at the level of 1 x 10-17 is a testimony to our understanding of a quantum many-body system and it removes an important obstacle for building an optical atomic clock based on such systems with high accuracy. [4pt] [1] A. D. Ludlow et al., Science 319, 1805 (2008). [0pt] [2] G. K. Campbell et al., Science 324, 360 (2009). [0pt] [3] M. D. Swallows et al., Science 331, 1043 (2011).

Ye, Jun

2011-10-01

159

Cuban Techno-physical Experiments in Space  

NASA Astrophysics Data System (ADS)

When Cuba joined the Intercosmos Program of the socialist countries in the mid-1960s, the great educational and scientific reform taking place at that time in the country had hardly begun to bear fruit. But when, a decade later, the Soviet Union offered all the participant countries the chance to make use of its space vehicles and related installations so that their cosmonauts could carry out original scientific experiments in space, the situation had changed radically in Cuba. In a short time around 200 people already involved in scientific and technological activities succeeded in designing and setting up—in close collaboration with various Soviet, East German and Bulgarian institutions—some 20 scientific experiments that were to be carried out in orbit around the earth during the joint Soviet-Cuban space flight of September 18-26, 1980. Those experiments, and a further one that was also set up for the same space flight—but carried out during a later flight, as mentioned below—are historically important since they were the first in their class to be carried out by humans in space under microgravity conditions.

Altshuler, José; Calzadilla Amaya, Ocatvio; Falcon, Federico; Fuentes, Juan E.; Lodos, Jorge; Vigil Santos, Elena

160

Distributed System of Processing of Data of Physical Experiments  

NASA Astrophysics Data System (ADS)

Complication of physical experiments and increasing volumes of experimental data necessitate the application of supercomputer and distributed computing systems for data processing. Design and development of such systems, their mathematical modeling, and investigation of their characteristics and functional capabilities is an urgent scientific and practical problem. In the present work, the characteristics of operation of such distributed system of processing of data of physical experiments are investigated using the apparatus of theory of queuing networks.

Nazarov, A. A.; Moiseev, A. N.

2014-11-01

161

Ground Control to Niels Bohr: Exploring Outer Space with Atomic Physics  

E-print Network

We provided an introduction to transition state theory and the connections it provides between atomic and celestial physics. We include brief discussions of historical background, recent applications in space mission design, and current research efforts.

Mason A. Porter; Predrag Cvitanovic

2005-05-11

162

Request for Support for the Conference on Super Intense Laser Atom Physics  

SciTech Connect

The Conference on Super Intense Laser Atom Physics (SILAP) was held in November 2003 in Dallas, Texas. The venue for the meeting was South Fork Ranch in the outskirts of Dallas. The topics of the meeting included high harmonic generation and attosecond pulse generation, strong field interactions with molecules and clusters, particle acceleration, and relativistic laser atom interactions.

Todd Ditmire

2004-10-21

163

PHYSICAL REVIEW B 86, 134116 (2012) Embedded-atom potential for hcp and fcc cobalt  

E-print Network

PHYSICAL REVIEW B 86, 134116 (2012) Embedded-atom potential for hcp and fcc cobalt G. P. Purja Pun of an embedded-atom interatomic potential representing basic properties of both the hcp and the fcc phases. In a more general context, it offers a model for studying thermodynamic and kinetic properties of hcp/fcc

Mishin, Yuri

164

PHYSICAL REVIEW A 87, 013413 (2013) Spin damping in an rf atomic magnetometer  

E-print Network

PHYSICAL REVIEW A 87, 013413 (2013) Spin damping in an rf atomic magnetometer Orang Alem* and Karen factor Q of a radio-frequency atomic magnetometer can be decreased by more than two orders of magnitude the magnetometer for detection of the desired signal. We find that noise is also suppressed under such spin damping

Romalis, Mike

165

Divertor design for the tokamak physics experiment  

NASA Astrophysics Data System (ADS)

In this paper we discuss the divertor design for the planned TPX tokamak, which will explore the physics and technology of steady state (1000 s pulses) heat and particle removal in high confinement (up to 4 × L-mode), high beta (up to ?N = 5) divertor plasmas sustained by non-inductive current drive. TPX will operate in the double-null divertor configuration, with actively cooled graphite targets forming a deep (0.57 m) slot at the outer strike point. The peak heat flux on the highly tilted (74° from normal) re-entrant divertor plate (tilted to recycle ions back toward the separatrix) will be in the range of 4-6 MW/m 2 with 17.5 MW of auxiliary heating power. The combination of pumping and gas puffing (D 2 plus impurities), along with higher heating power (45 MW maximum) will allow testing of radiative divertor concepts at ITER-like power densities.

Hill, D. N.; Braams, B.; Brooks, J. N.; Ruzic, D. N.; Ulrickson, M.; Werley, K. A.; Campbell, R.; Goldston, R.; Kaiser, T.; Neilson, G. H.; Mioduszewski, P.; Rensink, M. E.; Rognlien, T. D.

1995-04-01

166

Atomic clocks and coherent population trapping: Experiments for undergraduate laboratories  

NASA Astrophysics Data System (ADS)

We demonstrate how to construct and operate a simple and affordable apparatus for producing coherent effects in atomic vapor and for investigating their applications in time-keeping and magnetometry. The apparatus consists of a vertical cavity surface emitting diode laser directly current-modulated using a tunable microwave oscillator to produce multiple optical fields needed for the observation of coherent population trapping. This effect allows very accurate measurement of the transition frequency between two ground state hyperfine sublevels, which can be used to construct a coherent population trapping-based atomic clock.

Belcher, Nathan; Mikhailov, Eugeniy E.; Novikova, Irina

2009-11-01

167

Perceptions of Overweight Students Concerning Their Experiences in Physical Education  

ERIC Educational Resources Information Center

The purpose of this investigation was to examine overweight students' perceptions of and experiences in physical education. Specifically, the applicability of learned helplessness as a framework to understand their experiences was explored. Participants were seven female and five male high school students whose body mass index was at or higher…

Trout, Josh; Graber, Kim C.

2009-01-01

168

Bicycle Freewheeling with Air Drag as a Physics Experiment  

ERIC Educational Resources Information Center

To familiarize first-year students with the important ingredients of a physics experiment, we offer them a project close to their daily life: measuring the effect of air resistance on a bicycle. Experiments are done with a bicycle freewheeling on a downhill slope. The data are compared with equations of motions corresponding to different models…

Janssen, Paul; Janssens, Ewald

2015-01-01

169

Divertor design for the Tokamak Physics Experiment  

NASA Astrophysics Data System (ADS)

In this paper we discuss the present divertor design for the planned TPX tokamak, which will explore the physics and technology of steady-state (1000s pulses) heat and particle removal in high confinement (2-4 x L-mode), high beta (beta(sub N) greater than or equal to 3) divertor plasmas sustained by non-induct ive current drive. The TPX device will operate in the double-null divertor configuration, with actively cooled graphite targets forming a deep (0.5 m) slot at the outer strike point. The peak heat flux on, the highly tilted (74 deg) from normal) re-entrant (to recycle ions back toward the separatrix) will be in the range of 4-6 MW/sq m with 18 MW of neutral beams and RF heating power. The combination of active pumping and gas puffing (deuterium plus impurities), along with higher heating power (45 MW maximum) will allow testing of radiative divertor concepts at ITER-like power densities.

Hill, D. N.; Braams, B.; Brooks, J. N.; Ruzic, D. N.; Ulrickson, M.; Werley, K. A.; Campbell, R.; Goldston, R.; Kaiser, T.; Nellson, G. H.

1994-05-01

170

Divertor design for the Tokamak Physics Experiment  

SciTech Connect

In this paper we discuss the present divertor design for the planned TPX tokamak, which will explore the physics and technology of steady-state (1000s pulses) heat and particle removal in high confinement (2--4{times} L-mode), high beta ({beta}{sub N} {ge} 3) divertor plasmas sustained by non-inductive current drive. The TPX device will operate in the double-null divertor configuration, with actively cooled graphite targets forming a deep (0.5 m) slot at the outer strike point. The peak heat flux on, the highly tilted (74{degrees} from normal) re-entrant (to recycle ions back toward the separatrix) will be in the range of 4--6 MW/m{sup 2} with 18 MW of neutral beams and RF heating power. The combination of active pumping and gas puffing (deuterium plus impurities), along with higher heating power (45 MW maximum) will allow testing of radiative divertor concepts at ITER-like power densities.

Hill, D.N. [Lawrence Livermore National Lab., CA (United States); Braams, B. [New York Univ., NY (United States). Courant Inst.; Brooks, J.N. [Argonne National Lab., IL (United States)

1994-05-01

171

Stars and statistical physics: A teaching experience  

NSDL National Science Digital Library

The physics of stars is a goldmine of problems in statistical mechanics and thermodynamics. We discuss many examples that illustrate the possibility of deepening studentâs knowledge of statistical mechanics by an introductory study of stars. The matter constituting the various stellar objects provides examples of equations of state for classical or quantum and relativistic or non-relativistic gases. Maximum entropy can be used to characterize thermodynamic and gravitational equilibrium which determines the structure of stars and predicts their instability above a certain mass. Contraction accompanying radiation induces either heating or cooling, which explains the formation of stars above a minimum mass. The characteristics of the emitted light are understood from blackbody radiation and from the BoltzmannâLorentz kinetic equation for photons. The luminosity is governed by the transport of heat by photons from the center to the surface. Heat production by thermonuclear fusion is determined by microscopic balance equations. The stability of the steady state of stars is controlled by the interplay of thermodynamics and gravitation.

Balian, Roger; Blaizot, Jean-Paul

2011-08-30

172

Atomic and Molecular Electron Affinities: Photoelectron Experiments and Theoretical Computations  

E-print Network

in biological systems,33-35 and elec- tron attachment to nucleic acid bases.36,37 Such examples demonstrate-0215 Received June 13, 2001 Contents I. Introduction and Scope 231 A. Definitions of Atomic Electron Affinities 233 B. Definitions of Molecular Electron Affinities 233 II. Experimental Photoelectron Electron

Ellison, Barney

173

Compilation of current high-energy physics experiments  

SciTech Connect

This is the fourth edition of the compilation of current high energy physics experiments. It is a collaborative effort of the Berkeley Particle Data Group, the SLAC library, and nine participating laboratories: Argonne (ANL), Brookhaven (BNL), CERN, DESY, Fermilab (FNAL), the Institute for Nuclear Study, Tokyo (INS), KEK, Serpukhov (SERP), and SLAC. The compilation includes summaries of all high energy physics experiments at the above laboratories that (1) were approved (and not subsequently withdrawn) before about April 1981, and (2) had not completed taking of data by 1 January 1977. Only approved experiments are included.

Wohl, C.G.; Kelly, R.L.; Armstrong, F.E.

1981-05-01

174

Long Pulse Fusion Physics Experiments without Superconducting Electromagnets  

SciTech Connect

Long-pulse fusion physics experiments can be performed economically via resistive electromagnets designed for thermally steady-state operation. Possible fusion experiments using resistive electromagnets include long-pulse ignition with deuterium-tritium fuel. Long-pulse resistive electromagnets are alternatives to today's delicate and costly superconductors. At any rate, superconducting technology is now evolving independent of fusion, so near-term superconducting experience may not ultimately be useful.

Woolley, R.D.

1998-08-19

175

INSPIRE - Premission. [Interactive NASA Space Physics Ionosphere Radio Experiment  

NASA Technical Reports Server (NTRS)

The Interactive NASA Space Physics Ionosphere Radio Experiment (INSPIRE) designed to assist in a Space Experiments with Particle Accelerators (SEPAC) project is discussed. INSPIRE is aimed at recording data from a large number of receivers on the ground to determine the exact propagation paths and absorption of radio waves at frequencies between 50 Hz and 7 kHz. It is indicated how to participate in the experiment that will involve high school classes, colleges, and amateur radio operators.

Taylor, William W. L.; Mideke, Michael; Pine, William E.; Ericson, James D.

1992-01-01

176

Model of delocalized atoms in the physics of the vitreous state  

SciTech Connect

A development of the model of delocalized atoms of liquids and glasses is proposed. It is shown that the basic equation of the model for the probability of delocalization (excitation) of an atom can be obtained not only from the Clausius relation but also by other methods of statistical physics. Techniques for calculating the parameters of the model are developed. The critical displacement of an atom from the equilibrium position, which corresponds to the maximum interatomic attraction force, can be considered as a delocalization (local excitation) of this atom in an elastic continuum. The energy of the critical displacement of an atom calculated as the work of the limit elastic deformation of the interatomic bond in an elastic continuum is in agreement with the results of calculation by the model of delocalized atoms. This energy can also be calculated from the data on surface tension and atomic volume. In silicate glasses, the process of delocalization of an atom represents the critical displacement of a bridging oxygen atom in the structural fragment of a silicon-oxygen (Si-O-Si) network before the switching of the valence bond, whereas, in amorphous organic polymers, the delocalization of an atom corresponds to the limit displacement of a fragment of the main chain of a macromolecule (a group of atoms in the connecting link).

Sanditov, D. S., E-mail: Sanditov@bsu.ru [Buryat State University (Russian Federation)

2012-07-15

177

PHYSICAL REVIEW A 84, 043408 (2011) Magic-wavelength optical traps for Rydberg atoms  

E-print Network

(Received 12 June 2011; published 6 October 2011) We propose blue-detuned optical traps that are suitable quantum gate experiments have used Rb atoms that are laser cooled and then transferred into red-detuned far-off resonance optical traps (FORTs). Red-detuned traps are adequate for ground-state atoms

Yavuz, Deniz

178

Atomic physics with hard X-rays from high brilliance synchrotron light sources  

SciTech Connect

A century after the discovery of x rays, the experimental capability for studying atomic structure and dynamics with hard, bright synchrotron radiation is increasing remarkably. Tempting opportunities arise for experiments on many-body effects, aspects of fundamental photon-atom interaction processes, and relativistic and quantum-electrodynamic phenomena. Some of these possibilities are surveyed in general terms.

Southworth, S.; Gemmell, D.

1996-08-01

179

Atomic Molecular and Optical Physics Laboratory Toshiyuki Azuma Division of Genomic Technologies (Center for Life Science Technologies) Piero Carninci  

E-print Network

Laboratory Atsushi Mochizuki Strong Correlation Physics Division (Center for Emergent Matter Science) Naoto Physics Laboratory (Nishina Center for Accelerator-Based Science) Hiroyoshi Sakurai Cellular MemoryAtomic Molecular and Optical Physics Laboratory Toshiyuki Azuma Division of Genomic Technologies

Fukai, Tomoki

180

Modeling Bohr's theory of hydrogen atom for physics and chemistry education, and computer science graduates  

Microsoft Academic Search

This article is basically targeted for the advanced university and college undergraduate and graduate students of physics and chemistry education, computational physics and chemistry, and computer science. Here, we employed Microsoft Excel software system to perform computer simulations for modeling Bohr's theory of hydrogen atom in college and university classroom setting. We developed necessary computer algorithm to compute discrete values

Gurmukh Singh; Amitabha Mukhopadyay

2010-01-01

181

PREFACE: 8th Asian International Seminar on Atomic and Molecular Physics (AISAMP)  

NASA Astrophysics Data System (ADS)

These proceedings arose from the 8th Asian International Seminar on Atomic and Molecular Physics (AISAMP) which was held at the University of Western Australia 24-28 November 2008. The history of AISAMP (Takayanagi and Matsuzawa 2002) recognizes its origin from the Japan-China meeting of 1985, and the first use of the name 'The First Asian International Seminar on Atomic and Molecular Physics (AISAMP)' in 1992. The initial attendees, Japan and China, were joined subsequently by scientists from Korea, Taiwan, India, Australia and recently by Malaysia, Thailand, Vietnam, Turkey Iran, UK and USA. The main purpose of the biennial AISAMP series is to create a wide forum for exchanging ideas and information among atomic and molecular scientists and to promote international collaboration. The scope of the AISAMP8 meeting included pure, strategic and applied research involving atomic and molecular structure and processes in all forms of matter and antimatter. For 2008 the AISAMP conference incorporated the Australian Atomic and Molecular Physics and Quantum Chemistry meeting. The topics for AISAMP8 embraced themes from earlier AISAMP meetings and reflected new interests, in atomic and molecular structures, spectroscopy and collisions; atomic and molecular physics with laser or synchrotron radiation; quantum information processing using atoms and molecules; atoms and molecules in surface physics, nanotechnology, biophysics, atmospheric physics and other interdisciplinary studies. The implementation of the AISAMP themes, as well as the international representation of research interests, is indicated both in the contents list of these published manuscripts as well as in the program for the meeting. Altogether, 184 presentations were made at the 8th AISAMP, including Invited Talks and Contributed Poster Presentations, of which 60 appear in the present Proceedings after review by expert referees in accordance with the usual practice of Journal of Physics: Conference Series of the Institute of Physics. The support from the IOPCS staff made this publication possible. The 8th AISAMP was sponsored primarily by the University of Western Australia and Curtin University of Technology, both in Perth, Western Australia, and by Journal of Physics: Conference Series. Support was also received from the International Council of Science, ICSU. Guidance and active participation from colleagues, particularly from the University of Western Australia, and Curtin University, and from the Australian National University and Melbourne University were sources of strength for the actual organization of the conference. Dr Elena Semidelova receives special thanks for her organizing abilities. We hope that this issue of Journal of Physics: Conference Series will be referenced widely and that it will strengthen ties between all scientists and their countries. Evan Bieske, Stephen Buckman and Jim F Williams Guest Editors

Williams, Jim F.; Buckman, Steve; Bieske, Evan J.

2009-09-01

182

Improving the Physical Realism and Structural Accuracy of Protein Models by a Two-Step Atomic-Level Energy Minimization  

E-print Network

Improving the Physical Realism and Structural Accuracy of Protein Models by a Two-Step Atomic-step, atomic-level energy minimization. The main-chain structures are first constructed from initial Ca traces physics- and knowledge-based force field. We tested the method by performing an atomic structure

Zhang, Yang

183

Current experiments in particle physics - particle data group  

SciTech Connect

This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries.

Galic, H. [Stanford Univ., CA (United States). Stanford Linear Accelerator Center; Lehar, F. [Centre d`Etudes Nucleaires de Saclay, Gif-sur-Yvette (France); Kettle, P.R. [Paul Scherrer Institute, Villigen (Switzerland)] [and others

1996-09-01

184

PHYSICAL REVIEW A 87, 063408 (2013) Nondestructive light-shift measurements of single atoms in optical dipole traps  

E-print Network

PHYSICAL REVIEW A 87, 063408 (2013) Nondestructive light-shift measurements of single atoms atoms using a nondestructive detection technique that allows us to measure the fluorescent signal of one of single atoms [4], cooling [5,6], nondestructive state measurement [7,8], multidimensional atomic

Chapman, Michael

185

Compilation of current high-energy-physics experiments  

SciTech Connect

This is the third edition of a compilation of current high energy physics experiments. It is a collaborative effort of the Berkeley Particle Data Group, the SLAC library, and ten participating laboratories: Argonne (ANL), Brookhaven (BNL), CERN, DESY, Fermilab (FNAL), the Institute for Nuclear Study, Tokyo (INS), KEK, Rutherford (RHEL), Serpukhov (SERP), and SLAC. The compilation includes summaries of all high energy physics experiments at the above laboratories that (1) were approved (and not subsequently withdrawn) before about January 1980, and (2) had not completed taking of data by 1 January 1976.

Wohl, C.G.; Kelly, R.L.; Armstrong, F.E.

1980-04-01

186

Decoherence models for discrete-time quantum walks and their application to neutral atom experiments  

NASA Astrophysics Data System (ADS)

We discuss decoherence in discrete-time quantum walks in terms of a phenomenological model that distinguishes spin and spatial decoherence. We identify the dominating mechanisms that affect quantum-walk experiments realized with neutral atoms walking in an optical lattice. From the measured spatial distributions, we determine with good precision the amount of decoherence per step, which provides a quantitative indication of the quality of our quantum walks. In particular, we find that spin decoherence is the main mechanism responsible for the loss of coherence in our experiment. We also find that the sole observation of ballistic—instead of diffusive—expansion in position space is not a good indicator of the range of coherent delocalization. We provide further physical insight by distinguishing the effects of short- and long-time spin dephasing mechanisms. We introduce the concept of coherence length in the discrete-time quantum walk, which quantifies the range of spatial coherences. Unexpectedly, we find that quasi-stationary dephasing does not modify the local properties of the quantum walk, but instead affects spatial coherences. For a visual representation of decoherence phenomena in phase space, we have developed a formalism based on a discrete analogue of the Wigner function. We show that the effects of spin and spatial decoherence differ dramatically in momentum space.

Alberti, Andrea; Alt, Wolfgang; Werner, Reinhard; Meschede, Dieter

2014-12-01

187

Simulation of Physical Experiments in Immersive Virtual Environments  

NASA Technical Reports Server (NTRS)

An object-oriented event-driven immersive Virtual environment is described for the creation of virtual labs (VLs) for simulating physical experiments. Discussion focuses on a number of aspects of the VLs, including interface devices, software objects, and various applications. The VLs interface with output devices, including immersive stereoscopic screed(s) and stereo speakers; and a variety of input devices, including body tracking (head and hands), haptic gloves, wand, joystick, mouse, microphone, and keyboard. The VL incorporates the following types of primitive software objects: interface objects, support objects, geometric entities, and finite elements. Each object encapsulates a set of properties, methods, and events that define its behavior, appearance, and functions. A container object allows grouping of several objects. Applications of the VLs include viewing the results of the physical experiment, viewing a computer simulation of the physical experiment, simulation of the experiments procedure, computational steering, and remote control of the physical experiment. In addition, the VL can be used as a risk-free (safe) environment for training. The implementation of virtual structures testing machines, virtual wind tunnels, and a virtual acoustic testing facility is described.

Noor, Ahmed K.; Wasfy, Tamer M.

2001-01-01

188

Nuclear physics (of the cell, not the atom)  

PubMed Central

The nucleus is physically distinct from the cytoplasm in ways that suggest new ideas and approaches for interrogating the operation of this organelle. Chemical bond formation and breakage underlie the lives of cells, but as this special issue of Molecular Biology of the Cell attests, the nonchemical aspects of cell nuclei present a new frontier to biologists and biophysicists. PMID:25368422

Pederson, Thoru; Marko, John F.

2014-01-01

189

Physical state of interstellar atoms. [from Copernicus satellite UV data  

NASA Technical Reports Server (NTRS)

Brief survey of the physical conditions along the lines of sight to reddened and unreddened stars, as determined from Copernicus observation of interstellar lines between 95 and 300 nm. Differences in ionization structure and density between clouds and the local intercloud medium are discussed. Some new data for beta Centauri is used to supplement the previously available data.

York, D. G.

1974-01-01

190

Nuclear physics (of the cell, not the atom).  

PubMed

The nucleus is physically distinct from the cytoplasm in ways that suggest new ideas and approaches for interrogating the operation of this organelle. Chemical bond formation and breakage underlie the lives of cells, but as this special issue of Molecular Biology of the Cell attests, the nonchemical aspects of cell nuclei present a new frontier to biologists and biophysicists. PMID:25368422

Pederson, Thoru; Marko, John F

2014-11-01

191

Transport Experiments on 2D Correlated Electron Physics in Semiconductors  

SciTech Connect

This research project was designed to investigate experimentally the transport properties of the 2D electrons in Si and GaAs, two prototype semiconductors, in several new physical regimes that were previously inaccessible to experiments. The research focused on the strongly correlated electron physics in the dilute density limit, where the electron potential energy to kinetic energy ratio rs>>1, and on the fractional quantum Hall effect related physics in nuclear demagnetization refrigerator temperature range on samples with new levels of purity and controlled random disorder.

Tsui, Daniel

2014-03-24

192

The Physics Case for the New Muon (g-2) Experiment  

Microsoft Academic Search

This White Paper briefly reviews the present status of the muon (g-2) experiment and the physics motivation for a new effort. The present comparison between experiment and theory indicates a tantalizing $3.4 \\\\sigma$ deviation. An improvement in precision on this comparison by a factor of 2--with the central value remaining unchanged--will exceed the ``discovery'' threshold, with a sensitivity above $6

David W. Hertzog; James P. Miller; Eduardo de Rafael; B. Lee Roberts; Dominik Stockinger

2007-01-01

193

MIT Physics 8.02: Experiment - Electrostatic Force  

NSDL National Science Digital Library

This is an instructor's guide for an experiment to measure electrostatic force, using parallel plates made from two washers, insulating perf-board, and aluminum foil. Photos and detailed instructions are provided for experimental setup. SEE RELATED MATERIALS for a Java simulation by the same authors on the topic of capacitance. For an Excel spreadsheet developed specifically to accompany this experiment, see link below: MIT Physics 8.02 Open Courseware: Labs

2010-04-14

194

The Laboratory of Atomic & Solid State Physics (LASSP) at Cor nell University expects to make a faculty appointment in theo  

E-print Network

The Laboratory of Atomic & Solid State Physics (LASSP) at Cor nell University expects to make Position The Laboratory of Atomic & Solid State Physics Cornell and LASSP have a strong commitment to both a faculty appointment in theo re cal physics, to begin on July 1, 2015. We encourage applica ons focused

Wang, Z. Jane

195

Probing the Physical Conditions of Atomic Gas at High Redshift  

E-print Network

A new method is used to measure the physical conditions of the gas in damped Lyman-alpha systems (DLAs). Using high resolution absorption spectra of a sample of 80 DLAs, we are able to measure the ratio of the upper to lower fine-structure levels of the ground state of C II and Si II. These ratios are determined solely by the physical conditions of the gas. We explore the allowed physical parameter space using a Monte Carlo Markov Chain method to constrain simultaneously the temperature, neutral hydrogen density, and electron density of each DLA. The results indicate that at least 5 % of all DLAs have the bulk of their gas in a dense, cold phase with typical densities of ~100 cm-3 and temperatures below 500 K. We further find that the typical pressure of DLAs in our sample is log(P/k) = 3.4 [K cm-3], which is comparable to the pressure of the local interstellar medium (ISM), and that the components containing the bulk of the neutral gas can be quite small with absorption sizes as small as a few parsec. We sho...

Neeleman, Marcel; Wolfe, Arthur M

2014-01-01

196

Advanced Experiments in Nuclear Science, Volume I: Advanced Nuclear Physics and Chemistry Experiments.  

ERIC Educational Resources Information Center

The experiments in this manual represent state-of-the-art techniques which should be within the budgetary constraints of a college physics or chemistry department. There are fourteen experiments divided into five modules. The modules are on X-ray fluorescence, charged particle detection, neutron activation analysis, X-ray attenuation, and…

Duggan, Jerome L.; And Others

197

Feasibility guidelines for kaonic atom experiments with ultra-high-resolution X-ray spectrometry  

NASA Astrophysics Data System (ADS)

Recent studies of strong-interaction effects in kaonic atoms suggest that analysing so-called 'lower' and 'upper' levels in the same atom could separate one-nucleon absorption from multinucleon processes. The present work examines the feasibility of direct measurements of upper level widths in addition to lower level widths in future experiments, using superconducting microcalorimeter detectors. About ten elements are identified as possible candidates for such experiments, all of medium-weight and heavy nuclei. New experiments focused on achieving good accuracy for widths of such pairs of levels could contribute significantly to our knowledge of the K--nucleon interaction in the nuclear medium.

Friedman, E.; Okada, S.

2013-10-01

198

PSU-Physics PH-315 Andres La Rosa EXPERIMENT 1  

E-print Network

PSU-Physics PH-315 Andres La Rosa EXPERIMENT 1 RLC SERIES CIRCUIT RESONANCE (Complex impedance-dependence of the impedance and the phase in an AC circuit. To use series resonance to determine the inductance of a coil number of phase : L R C v i Fig.1 RLC series circuit. #12;vOSOS j 1 ) 1 ( (( 22 )) CC C LR i

La Rosa, Andres H.

199

Chladni Patterns on Drumheads: A "Physics of Music" Experiment  

ERIC Educational Resources Information Center

In our "Physics of Music" class for non-science majors, we have developed a laboratory exercise in which students experiment with Chladni sand patterns on drumheads. Chladni patterns provide a kinesthetic, visual, and entertaining way to illustrate standing waves on flat surfaces and are very helpful when making the transition from one-dimensional…

Worland, Randy

2011-01-01

200

Multidisciplinary Field Training in Undergraduate Physical Geography: Russian Experience  

ERIC Educational Resources Information Center

Field training is seen as a central component of the discipline of Physical Geography and an essential part of the undergraduate curriculum. This paper explores the structure and relationships between fieldwork and theoretical courses and the abundant experiences of field training in the undergraduate curriculum of 37 Russian universities. It…

Kasimov, Nikolay S.; Chalov, Sergey R.; Panin, Andrey V.

2013-01-01

201

Proceedings of the workshop on opportunities for atomic physics using slow, highly-charged ions  

SciTech Connect

The study of atomic physics with highly-charged ions is an area of intense activity at the present time because of a convergence of theoretical interest and advances in experimental techniques. The purpose of the Argonne ''Workshop on Opportunities for Atomic Physics Using Slow, Highly-Charged Ions'' was to bring together atomic, nuclear, and accelerator physicists in order to identify what new facilities would be most useful for the atomic physics community. The program included discussion of existing once-through machines, advanced ion sources, recoil ion techniques, ion traps, and cooler rings. One of the topics of the Workshop was to discuss possible improvement to the ANL Tandem-Linac facility (ATLAS) to enhance the capability for slowing down ions after they are stripped to a high-charge state (the Accel/Decel technique). Another topic was the opportunity for atomic physics provided by the ECR ion source which is being built for the Uranium Upgrade of ATLAS. 18 analytics were prepared for the individual papers in this volume.

Not Available

1987-01-01

202

Probing the Physical Conditions of Atomic Gas at High Redshift  

NASA Astrophysics Data System (ADS)

A new method is used to measure the physical conditions of the gas in damped Ly? systems (DLAs). Using high-resolution absorption spectra of a sample of 80 DLAs, we are able to measure the ratio of the upper and lower fine-structure levels of the ground state of C+ and Si+. These ratios are determined solely by the physical conditions of the gas. We explore the allowed physical parameter space using a Monte Carlo Markov chain method to constrain simultaneously the temperature, neutral hydrogen density, and electron density of each DLA. The results indicate that at least 5% of all DLAs have the bulk of their gas in a dense, cold phase with typical densities of ~100 cm–3 and temperatures below 500 K. We further find that the typical pressure of DLAs in our sample is log (P/kB ) = 3.4 (K cm–3), which is comparable to the pressure of the local interstellar medium (ISM), and that the components containing the bulk of the neutral gas can be quite small with absorption sizes as small as a few parsecs. We show that the majority of the systems are consistent with having densities significantly higher than expected for a purely canonical warm neutral medium, indicating that significant quantities of dense gas (i.e., n H > 0.1 cm–3) are required to match observations. Finally, we identify eight systems with positive detections of Si II*. These systems have pressures (P/kB ) in excess of 20,000 K cm–3, which suggest that these systems tag a highly turbulent ISM in young, star-forming galaxies.

Neeleman, Marcel; Prochaska, J. Xavier; Wolfe, Arthur M.

2015-02-01

203

Lasers as a Bridge between Atomic and Nuclear Physics  

E-print Network

This paper reviews the application of optical and UV laser radiation to several topics in low-energy nuclear physics. We consider the laser-induced nuclear anti-Stokes transitions, the laser-assisted and the laser-induced internal conversion, and the Electron Bridge and Inverse Electron Bridge mechanisms as tools for deexciting and exciting of low-lying nuclear isomeric states. A study of the anomalous, by low-lying, nuclear isomeric states (on an example of the $^{229}$Th nucleus) is presented in detail.

Sergei G. Matinyan

1997-06-02

204

Speculative Physics: the Ontology of Theory and Experiment in High Energy Particle Physics and Science Fiction  

E-print Network

The dissertation brings together approaches across the fields of physics, critical theory, literary studies, philosophy of physics, sociology of science, and history of science to synthesize a hybrid approach for instigating more rigorous and intense cross-disciplinary interrogations between the sciences and the humanities. There are two levels of conversations going on in the dissertation; at the first level, the discussion is centered on a critical historiography and philosophical implications of the discovery Higgs boson in relation to its position at the intersection of old (current) and the potential for new possibilities in quantum physics; I then position my findings on the Higgs boson in connection to the double-slit experiment that represents foundational inquiries into quantum physics, to demonstrate the bridge between fundamental physics and high energy particle physics. The conceptualization of the variants of the double-slit experiment informs the aforementioned critical comparisons. At the second level of the conversation, theories are produced from a close study of the physics objects as speculative engine for new knowledge generation that are then reconceptualized and re-articulated for extrapolation into the speculative ontology of hard science fiction, particularly the hard science fiction written with the double intent of speaking to the science while producing imaginative and socially conscious science through the literary affordances of science fiction. The works of science fiction examined here demonstrate the tension between the internal values of physics in the practice of theory and experiment and questions on ethics, culture, and morality.

Clarissa Ai Ling Lee

2014-06-21

205

Fluid physics, thermodynamics, and heat transfer experiments in space  

NASA Technical Reports Server (NTRS)

An overstudy committee was formed to study and recommend fundamental experiments in fluid physics, thermodynamics, and heat transfer for experimentation in orbit, using the space shuttle system and a space laboratory. The space environment, particularly the low-gravity condition, is an indispensable requirement for all the recommended experiments. The experiments fell broadly into five groups: critical-point thermophysical phenomena, fluid surface dynamics and capillarity, convection at reduced gravity, non-heated multiphase mixtures, and multiphase heat transfer. The Committee attempted to assess the effects of g-jitter and other perturbations of the gravitational field on the conduct of the experiments. A series of ground-based experiments are recommended to define some of the phenomena and to develop reliable instrumentation.

Dodge, F. T.; Abramson, H. N.; Angrist, S. W.; Catton, I.; Churchill, S. W.; Mannheimer, R. J.; Otrach, S.; Schwartz, S. H.; Sengers, J. V.

1975-01-01

206

Industrial metrology as applied to large physics experiments  

SciTech Connect

A physics experiment is a large complex 3-D object (typ. 1200 m{sup 3}, 35000 tonnes), with sub-millimetric alignment requirements. Two generic survey alignment tasks can be identified; first, an iterative positioning of the apparatus subsystems in space and, second, a quantification of as-built parameters. The most convenient measurement technique is industrial triangulation but the complexity of the measured object and measurement environment constraints frequently requires a more sophisticated approach. To enlarge the ``survey alignment toolbox`` measurement techniques commonly associated with other disciplines such as geodesy, applied geodesy for accelerator alignment, and mechanical engineering are also used. Disparate observables require a heavy reliance on least squares programs for campaign pre-analysis and calculation. This paper will offer an introduction to the alignment of physics experiments and will identify trends for the next generation of SSC experiments.

Veal, D.

1993-05-01

207

Computation of Free-Free Transitions in Atomic Physics: Foundations  

NASA Technical Reports Server (NTRS)

The amplitude T for "free-free" processes, such as bremsstrahlung or photo- absorption by an electron in the continuum in the presence of an external field, is usually written as the matrix element of the radiation operator taken between two continuum states. However, unlike the case when at least one of the states is bound, as in radiative transitions, electron capture, or the photo-effect, this expression contains an unphysical term, proportional to a delta-function and is not really the physical amplitude Tphys. This continues to be true for both the velocity and length form of the dipole approximation to the amplitude T. We first give an a priori definition of Tphys in terms of the scattering parts of the continuum functions, which has an obvious interpretation in terms of time-ordered diagrams. We then show that when the formal amplitude is modified by a long- distance cutoff, the modified form approaches Tphys as the cutoff is removed. The modified form then serves as a basis for the definition of a physical velocity dipole amplitude and this in turn leads to an equivalent length form of the dipole amplitude. This exercise provides a clear theoretical basis for many extant calculations in which cutoff factors are introduces somewhat ad hoc, as needed.

Bhatia, A. K.; Sucher, J.

2003-01-01

208

Combustion, Complex Fluids, and Fluid Physics Experiments on the ISS  

NASA Technical Reports Server (NTRS)

From the very early days of human spaceflight, NASA has been conducting experiments in space to understand the effect of weightlessness on physical and chemically reacting systems. NASA Glenn Research Center (GRC) in Cleveland, Ohio has been at the forefront of this research looking at both fundamental studies in microgravity as well as experiments targeted at reducing the risks to long duration human missions to the moon, Mars, and beyond. In the current International Space Station (ISS) era, we now have an orbiting laboratory that provides the highly desired condition of long-duration microgravity. This allows continuous and interactive research similar to Earth-based laboratories. Because of these capabilities, the ISS is an indispensible laboratory for low gravity research. NASA GRC has been actively involved in developing and operating facilities and experiments on the ISS since the beginning of a permanent human presence on November 2, 2000. As the lead Center for combustion, complex fluids, and fluid physics; GRC has led the successful implementation of the Combustion Integrated Rack (CIR) and the Fluids Integrated Rack (FIR) as well as the continued use of other facilities on the ISS. These facilities have supported combustion experiments in fundamental droplet combustion; fire detection; fire extinguishment; soot phenomena; flame liftoff and stability; and material flammability. The fluids experiments have studied capillary flow; magneto-rheological fluids; colloidal systems; extensional rheology; pool and nucleate boiling phenomena. In this paper, we provide an overview of the experiments conducted on the ISS over the past 12 years.

Motil, Brian; Urban, David

2012-01-01

209

The Physics Case for the New Muon (g-2) Experiment  

E-print Network

This White Paper briefly reviews the present status of the muon (g-2) experiment and the physics motivation for a new effort. The present comparison between experiment and theory indicates a tantalizing $3.4 \\sigma$ deviation. An improvement in precision on this comparison by a factor of 2--with the central value remaining unchanged--will exceed the ``discovery'' threshold, with a sensitivity above $6 \\sigma$. The 2.5-fold reduction improvement goal of the new Brookhaven E969 experiment, along with continued steady reduction of the standard model theory uncertainty, will achieve this more definitive test. Already, the (g-2) result is arguably the most compelling indicator of physics beyond the standard model and, at the very least, it represents a major constraint for speculative new theories such as supersymmetry or extra dimensions. In this report, we summarize the present experimental status and provide an up-to-date accounting of the standard model theory, including the expectations for improvement in the hadronic contributions, which dominate the overall uncertainty. Our primary focus is on the physics case that motivates improved experimental and theoretical efforts. Accordingly, we give examples of specific new-physics implications in the context of direct searches at the LHC as well as general arguments about the role of an improved (g-2) measurement. A brief summary of the plans for an upgraded effort complete the report.

David W. Hertzog; James P. Miller; Eduardo de Rafael; B. Lee Roberts; Dominik Stockinger

2007-05-31

210

Theory of neutrino-atom collisions: the history, present status and BSM physics  

E-print Network

An overview of the current theoretical studies on neutrino-atom scattering processes is presented. The ionization channel of these processes, which is studied in experiments searching for neutrino magnetic moments, is brought into focus. Recent developments in the theory of atomic ionization by impact of reactor antineutrinos are discussed. It is shown that the stepping approximation is well applicable for the data analysis practically down to the ionization threshold.

Konstantin A. Kouzakov; Alexander I. Studenikin

2014-06-19

211

Interactive Lecture Experiments in Large Introductory Physics Classes  

NASA Astrophysics Data System (ADS)

We describe Interactive Lecture Experiments (ILE), which build on Interactive Lecture Demonstrations proposed by Sokoloff and Thornton (2004) and extends it by providing students with the opportunity to analyze experiments demonstrated in the lecture outside of the classroom. Real time experimental data is collected, using Logger Pro combined with the digital video technology. This data is uploaded to the Internet and made available to the students for further analysis. Student learning is assessed in the following lecture using conceptual questions (clickers). The goal of this project is to use ILE to make large lectures more interactive and promote student interest in science, critical thinking and data analysis skills. We report on the systematic study conducted using the Colorado Learning Attitudes about Science Survey, Force Concept Inventory, open-ended physics problems and focus group interviews to determine the impact of ILE on student academic achievement, motivation and attitudes towards physics. Three sections of students (750 students) experienced four ILE experiments. The surveys were administered twice and academic results for students who experienced the ILE for a particular topic were compared to the students, from a different section, who did not complete the ILE for that topic. Additional qualitative data on students’ attitudes was collected using open ended survey questions and interviews. We will present preliminary conclusions about the role of ILEs as an effective pedagogy in large introductory physics courses. Sokoloff, D.R. and R.K. Thornton (2004). Interactive Lecture Demonstrations: Active Learning in Introductory Physics, J.Wiley & Sons, INC. Interactive Lecture Experiments: http://www.physics.ubc.ca/ year1lab/p100/LectureLabs/lectureLabs.html

Milner-Bolotin, Marina M.; Kotlicki, A.; Rieger, G.; Bates, F.; Moll, R.; McPhee, K.; Nashon, S.

2006-12-01

212

Statistical physics of human beings in games: Controlled experiments  

NASA Astrophysics Data System (ADS)

It is important to know whether the laws or phenomena in statistical physics for natural systems with non-adaptive agents still hold for social human systems with adaptive agents, because this implies whether it is possible to study or understand social human systems by using statistical physics originating from natural systems. For this purpose, we review the role of human adaptability in four kinds of specific human behaviors, namely, normal behavior, herd behavior, contrarian behavior, and hedge behavior. The approach is based on controlled experiments in the framework of market-directed resource-allocation games. The role of the controlled experiments could be at least two-fold: adopting the real human decision-making process so that the system under consideration could reflect the performance of genuine human beings; making it possible to obtain macroscopic physical properties of a human system by tuning a particular factor of the system, thus directly revealing cause and effect. As a result, both computer simulations and theoretical analyses help to show a few counterparts of some laws or phenomena in statistical physics for social human systems: two-phase phenomena or phase transitions, entropy-related phenomena, and a non-equilibrium steady state. This review highlights the role of human adaptability in these counterparts, and makes it possible to study or understand some particular social human systems by means of statistical physics coming from natural systems.

Liang, Yuan; Huang, Ji-Ping

2014-07-01

213

High-energy shadowing effect and its application to atomic and solid state physics  

Microsoft Academic Search

Ion-beam shadowing effects for projectiles in the MeV\\/u energy range have been studied with high-energy (keV) secondary electrons emitted from the surface of a target crystal. This article reviews and discusses applications of the high-energy shadowing effect to atomic and solid state physics, as well as physical and technical aspects of the electron spectroscopy under channeling incidence conditions.

Kudo Hiroshi; Shima Kunihiro; Ishihara Toyoyuki; Takeshita Hidefumi; Aoki Yasushi; Yamamoto Shunya; Naramoto Hiroshi

1994-01-01

214

Clock Technology Development in the Laser Cooling and Atomic Physics (LCAP) Program  

NASA Technical Reports Server (NTRS)

This paper presents the Laser Cooling and Atomic Physics (LCAP) program. It focuses on clock technology development. The topics include: 1) Overview of LCAP Flight Projects; 2) Space Clock 101; 3) Physics with Clocks in microgravity; 4) Space Clock Challenges; 5) LCAP Timeline; 6) International Space Station (ISS) Science Platforms; 7) ISS Express Rack; 8) Space Qualification of Components; 9) Laser Configuration; 10) Clock Rate Comparisons: GPS Carrier Phase Frequency Transfer; and 11) ISS Model Views. This paper is presented in viewgraph form.

Seidel, Dave; Thompson, R. J.; Klipstein, W. M.; Kohel, J.; Maleki, L.

2000-01-01

215

Elementary Particle Physics Experiment at the University of Massachusetts, Amherst  

SciTech Connect

In this progress report we summarize the activities of the University of Massachusetts- Amherst group for the three years of this research project. We are fully engaged in research at the energy frontier with the ATLAS experiment at the CERN Large Hadron Collider. We have made leading contributions in software development and performance studies for the ATLAS Muon Spectrometer, as well as on physics analysis with an emphasis on Standard Model measurements and searches for physics beyond the Standard Model. In addition, we have increased our contributions to the Muon Spectrometer New Small Wheel upgrade project.

Brau, Benjamin; Dallapiccola, Carlo; Willocq, Stephane

2013-07-30

216

PREFACE: 7th Asian International Seminar on Atomic and Molecular Physics  

NASA Astrophysics Data System (ADS)

These proceedings arose from the 7th Asian International Seminar on Atomic and Molecular Physics (AISAMP) which was held at the Indian Institute of Technology, Madras from 4-7 December 2006. The history of the AISAMP has been reviewed by Takayanagi http://www.physics.iitm.ac.in/~aisamp7/history.html. This international seminar/conference series grew out of the Japan-China meetings which were launched in 1985, the fourth of which was held in 1992 and carried a second title: The First Asian International Seminar on Atomic and Molecular Physics (AISAMP), thus providing a formal medium for scientists in this part of the world to report periodically and exchange their scientific thoughts. The founding nations of Japan and China were joined subsequently by Korea, Taiwan, India and Australia. The aims of the symposia included bringing together leading experts and students of atomic and molecular physics, the discussion of important problems, learning and sharing modern techniques and expanding the horizons of modern atomic and molecular physics. The fields of interest ranged from atomic and molecular structure and dynamics to photon, electron and positron scattering, to quantum information processing, the effects of symmetry and many body interactions, laser cooling, cold traps, electric and magnetic fields and to atomic and molecular physics with synchrotron radiation. Particular interest was evident in new techniques and the changes of the physical properties from atomic to condensed matter. Details of the 7th AISAMP, including the topics for the special sessions and the full programme, are available online at the conference website http://www.physics.iitm.ac.in/~aisamp7/. In total, 95 presentations were made at the 7th AISAMP, these included the Invited Talks and Contributed Poster Presentations, of which 52 appear in the present Proceedings after review by expert referees, refereed to the usual standard of the Institute of Physics journal: Journal of Physics B: Atomic, Molecular and Optical Physics. We received extensive support from the Journal of Physics: Conference Series staff; Graham Douglas, in particular, has been of tremendous help. The 7th AISAMP was very well attended and was sponsored primarily by the host Indian Institute of Technology, Madras (Chennai), the Board of Research in Nuclear Sciences, (Department of Atomic Energy, Government of India), the Department of Science and Technology, (Government of India), and the Asian Office of Aerospace Research and Development (AOARD) of the US Air Force. There was support from various quarters—each was invaluable and added to the success of the 7th AISAMP. We are very grateful to all the sponsors. It is superfluous to add that guidance and active participation from several colleagues within the host Institute was the primary source of strength for the actual organization of the conference and the multitude of arrangements for the organization came from the young graduate students at the IIT-Madras. We hope that this volume of Journal of Physics: Conference Series will be referenced widely and that it will strengthen ties between various countries in the region in and around Asia, and also of course to all scientists in this field the world over. Pranawa C Deshmukh, Purushottam Chakraborty and Jim F Williams Editors Conference photograph

Deshmukh, Pranawa C.; Chakraborty, Purushottam; Williams, Jim F.

2007-09-01

217

Physics Results from the Antiproton Experiment (APEX) at Fermilab  

DOE Data Explorer

Is Antimatter stable? The APEX experiment searches for the decay of antiprotons at the Fermilab Antiproton Accumulator. Observation of antiproton decay would indicate a violation of the CPT theorem, which is one of the most fundamental theorems of modern physics. The best laboratory limits on antiproton decay come from the APEX experiment which achieved a sensitivity to antiproton lifetimes up to of order 700,000 years for the most sensitive decay modes. Antiproton lifetimes in this range could arise from CPT violation at the Planck scale.[copied from http://www-apex.fnal.gov/] This website presents published results from the APEX Test Experiment (T861) and from the E868 Experiment. Limits were placed on six antiproton decay modes with a muon in the final state and on seven antiproton decay modes with an electron in the final state. See also the summary table and plot and the APEX picture gallery.

APEX Collaboration

218

Atomic Molecular and Optical Physics Laboratory Toshiyuki Azuma Division of Genomic Technologies (Center for Life Science Technologies) Piero Carninci  

E-print Network

Radioactive Isotope Physics Laboratory (Nishina Center for Accelerator-Based Science) Hiroyoshi SakuraiAtomic Molecular and Optical Physics Laboratory Toshiyuki Azuma Division of Genomic Technologies (Center for Life Science Technologies) Piero Carninci Computational Astrophysics Laboratory Toshikazu

Fukai, Tomoki

219

Precision determination of electroweak coupling from atomic parity violation and implications for particle physics.  

PubMed

We carry out high-precision calculation of parity violation in a cesium atom, reducing theoretical uncertainty by a factor of 2 compared to previous evaluations. We combine previous measurements with calculations and extract the weak charge of the 133Cs nucleus, QW=-73.16(29)expt(20)theor. The result is in agreement with the standard model (SM) of elementary particles. This is the most accurate to-date test of the low-energy electroweak sector of the SM. In combination with the results of high-energy collider experiments, we confirm the energy dependence (or "running") of the electroweak force over an energy range spanning 4 orders of magnitude (from approximately 10 MeV to approximately 100 GeV). Additionally, our result places constraints on a variety of new physics scenarios beyond the SM. In particular, we increase the lower limit on the masses of extra Z bosons predicted by models of grand unification and string theories. PMID:19518856

Porsev, S G; Beloy, K; Derevianko, A

2009-05-01

220

Experiences of Psychological and Physical Aggression in Adolescent Romantic Relationships: Links to Psychological Distress  

ERIC Educational Resources Information Center

Objective: This research examined links between adolescents' experiences of psychological and physical relationship aggression and their psychological distress. Experiences of psychological and physical aggression were expected to correlate positively with symptoms of psychological distress, but experiences of psychological aggression were…

Jouriles, Ernest N.; Garrido, Edward; Rosenfield, David; McDonald, Renee

2009-01-01

221

PHYSICAL REVIEW E 90, 012405 (2014) High-speed atomic force microscope imaging: Adaptive multiloop mode  

E-print Network

PHYSICAL REVIEW E 90, 012405 (2014) High-speed atomic force microscope imaging: Adaptive multiloop to substantially increase the speed of tapping mode (TM) imaging while preserving the advantages of TM imaging over technique. The speed of TM imaging, however, is substantially (over an order of magnitude) lower than

Lin, Zhiqun

222

Do General Physics Textbooks Discuss Scientists' Ideas about Atomic Structure? A Case in Korea  

ERIC Educational Resources Information Center

Research in science education has recognized the importance of teaching atomic structure within a history and philosophy of science perspective. The objective of this study is to evaluate general physics textbooks published in Korea based on the eight criteria developed in previous research. The result of this study shows that Korean general…

Niaz, Mansoor; Kwon, Sangwoon; Kim, Nahyun; Lee, Gyoungho

2013-01-01

223

Physics 6, 118 (2013) Looking for Hofstadter's Butterfly in Cold Atoms  

E-print Network

Physics 6, 118 (2013) Viewpoint Looking for Hofstadter's Butterfly in Cold Atoms Cheng Chin James, called the Hofstadter butterfly [1]. This effect has never been seen in a natural crystal, because of defects, they may ultimately provide the cleanest view of Hofstadter's butterfly. This system is also

224

Alpha Particle Physics Experiments in the Tokamak Fusion Test Reactor  

SciTech Connect

Alpha particle physics experiments were done on the Tokamak Fusion Test Reactor (TFTR) during its deuterium-tritium (DT) run from 1993-1997. These experiments utilized several new alpha particle diagnostics and hundreds of DT discharges to characterize the alpha particle confinement and wave-particle interactions. In general, the results from the alpha particle diagnostics agreed with the classical single-particle confinement model in magnetohydrodynamic (MHD) quiescent discharges. Also, the observed alpha particle interactions with sawteeth, toroidal Alfvén eigenmodes (TAE), and ion cyclotron resonant frequency (ICRF) waves were roughly consistent with theoretical modeling. This paper reviews what was learned and identifies what remains to be understood.

Budny, R.V.; Darrow, D.S.; Medley, S.S.; Nazikian, R.; Zweben, S.J.; et al.

1998-12-14

225

Bicycle Freewheeling with Air Drag as a Physics Experiment  

NASA Astrophysics Data System (ADS)

To familiarize first-year students with the important ingredients of a physics experiment, we offer them a project close to their daily life: measuring the effect of air resistance on a bicycle. Experiments are done with a bicycle freewheeling on a downhill slope. The data are compared with equations of motions corresponding to different models for the air resistance on a moving object. The relevant parameters are extracted from the data and the validity of the different models is be discussed. Finally findings are presented in a poster session.

Janssen, Paul; Janssens, Ewald

2015-01-01

226

Tevatron End-of-Run Beam Physics Experiments  

SciTech Connect

Before the Tevatron Collider Run II ended in September of 2011, a number of specialized beam study periods were dedicated to the experiments on various accelerator physics concepts and effects during the last year of the machine operation. The study topics included collimation with bent crystals and hollow electron beams, diffusion measurements and various aspects of beam-beam interactions. In this report we concentrate on the subject of beam-beam interactions, summarizing the results of beam experiments. The covered topics include offset collisions, coherent beam stability, effect of the bunch-length-to-beta-function ratio, and operation of AC dipole with colliding beams.

Valishev, A.; /Fermilab; Gu, X.; Miyamoto, R.; White, S.; /BNL; Schmidt, F.; /CERN; Qiang, J.; /LBNL

2012-05-01

227

Physics Regimes in the Fusion Ignition Research Experiment (FIRE)  

SciTech Connect

Burning plasma science is recognized widely as the next frontier in fusion research. The Fusion Ignition Research Experiment (FIRE) is a design study of a next-step burning plasma experiment with the goal of developing a concept for an experimental facility to explore and understand the strong nonlinear coupling among confinement, magnetohydrodynamic (MHD) self-heating, stability, edge physics, and wave-particle interactions that is fundamental to fusion plasma behavior. This will require plasmas dominated by alpha heating (Q greater than or equal to 5) that are sustained for a duration comparable to characteristic plasma timescales (greater than or equal to 10) tau(subscript ''E''), approximately 4 tau(subscript ''He''), approximately 2 tau(subscript ''skin''). The work reported here has been undertaken with the objective of finding the minimum size (cost) device to achieve these physics goals.

D.M. Meade; S.C.Jardin; C.E. Kessel; M.A. Ulrickson; J.H. Schultz; P.H. Rutherford; J.A. Schmidt; J.C. Wesley; K.M. Young; N.A.Uckan; R.J. Thome; P. Heitzenroeder; B.E. Nelson; and C.C.Baker

2001-06-19

228

The Physics Case for the New Muon (g-2) Experiment  

Microsoft Academic Search

This White Paper briefly reviews the present status of the muon (g-2)\\u000aexperiment and the physics motivation for a new effort. The present comparison\\u000abetween experiment and theory indicates a tantalizing $3.4 \\\\sigma$ deviation.\\u000aAn improvement in precision on this comparison by a factor of 2--with the\\u000acentral value remaining unchanged--will exceed the ``discovery'' threshold,\\u000awith a sensitivity above $6

David W. Hertzog; James P. Miller; Eduardo de Rafael; B. Lee Roberts

2007-01-01

229

Can There BE Physics Without Experiments? Challenges and Pitfalls  

NASA Astrophysics Data System (ADS)

Physicists investigating space, time and matter at the Planck scale will probably have to work with much less guidance from experimental input than has ever happened before in the history of Physics. This may imply that we should insist on much higher demands of logical and mathematical rigour than before. Working with long chains of arguments linking theories to experiment, we must be able to rely on logical precision when and where experimental checks cannot be provided.

't Hooft, Gerard

2014-03-01

230

Understanding the learning assistant experience with physics identity  

NSDL National Science Digital Library

Learning Assistants (LAs) have been shown to have better conceptual understanding and more favorable beliefs about science than non-LAs, and are more likely to choose a career in K-12 science teaching [1]. We propose that connections between elements of identity, persistence, and participation in an LA program can be explained using the concept of the community of practice and its intimate relationship to identity [2]. In separate work, Hazari et al. found that physics identity was highly correlated to expressed career plans in physics [3]. We hypothesize that a thriving LA program has many features of a well-functioning community of practice and contributes to all four elements of physics identity: personal interest, student performance, competence, and recognition by others. We explore how this analysis of the LA experience might shape decisions and influence outcomes of adoption and adaptations of the LA model.

Close, Eleanor W.; Close, Hunter G.; Donnelly, David

2014-02-19

231

Determination of Calcium in Cereal with Flame Atomic Absorption Spectroscopy: An Experiment for a Quantitative Methods of Analysis Course  

ERIC Educational Resources Information Center

An experiment for determination of calcium in cereal using two-increment standard addition method in conjunction with flame atomic absorption spectroscopy (FAAS) is demonstrated. The experiment is intended to introduce students to the principles of atomic absorption spectroscopy giving them hands on experience using quantitative methods of…

Bazzi, Ali; Kreuz, Bette; Fischer, Jeffrey

2004-01-01

232

Experience, gender, and performance: Connecting high school physics experience and gender differences to introductory college physics performance  

NASA Astrophysics Data System (ADS)

Current science educational practice is coming under heavy criticism based on the dismaying results of the Third International Mathematics and Science Study of 1998, the latest in a series of large scale surveys; and from research showing the appallingly low representation of females in science-related fields. These critical evaluations serve to draw attention to science literacy in general and lack of persistence among females in particular, two issues that relate closely to the "preparation for future study" goal held by many high school science teachers. In other words, these teachers often seek to promote future success and to prevent future failure in their students' academic careers. This thesis studies the connection between the teaching practices recommended by reformers and researchers for high school teachers, and their students' subsequent college physics performance. The teaching practices studied were: laboratory experiences, class discussion experiences, content coverage, and reliance on textbooks. This study analyzed a survey of 1500 students from 16 different lecture-format college physics courses at 14 different universities. Using hierarchical linear modeling, this study accounted for course-level variables (Calculus-based/Non-calculus course type, professor's gender, and university selectivity). This study controlled for the student's parents education, high school science/mathematics achievement, high school calculus background, and racial background. In addition, the interactions between gender and both pedagogical/curricular and course-level variables were analyzed. The results indicated that teaching fewer topics in greater depth in high school physics appeared to be helpful to college physics students. An interaction between college course type and content coverage showed that students in Calculus-based physics reaped even greater benefits from a depth-oriented curriculum. Also students with fewer labs per month in high school physics appeared to perform better in college physics than did students with many more labs per month. The only significant interaction was between gender and Calculus-based/Non-calculus college course type. Females appeared to do better on average than their males counterparts in Non-calculus physics, but this trend is clearly reversed for Calculus-based physics. This is a disturbing result for educators who have worked to promote persistence among women in engineering and science research. Recommendations are included for high school physics teachers, students and their parents, and college physics instructors.

Tai, Robert H.

233

WIMP physics with ensembles of direct-detection experiments  

NASA Astrophysics Data System (ADS)

The search for weakly-interacting massive particle (WIMP) dark matter is multi-pronged. Ultimately, the WIMP-dark-matter picture will only be confirmed if different classes of experiments see consistent signals and infer the same WIMP properties. In this work, we review the ideas, methods, and status of direct-detection searches. We focus in particular on extracting WIMP physics (WIMP interactions and phase-space distribution) from direct-detection data in the early discovery days when multiple experiments see of order dozens to hundreds of events. To demonstrate the essential complementarity of different direct-detection experiments in this context, we create mock data intended to represent the data from the near-future Generation 2 experiments. We consider both conventional supersymmetry-inspired benchmark points (with spin-independent and -dependent elastic cross sections just below current limits), as well as benchmark points for other classes of models (inelastic and effective-operator paradigms). We also investigate the effect on parameter estimation of loosening or dropping the assumptions about the local WIMP phase-space distribution. We arrive at two main conclusions. Firstly, teasing out WIMP physics with experiments depends critically on having a wide set of detector target materials, spanning a large range of target nuclear masses and spin-dependent sensitivity. It is also highly desirable to obtain data from low-threshold experiments. Secondly, a general reconstruction of the local WIMP velocity distribution, which will only be achieved if there are multiple experiments using different target materials, is critical to obtaining a robust and unbiased estimate of the WIMP mass.

Peter, Annika H. G.; Gluscevic, Vera; Green, Anne M.; Kavanagh, Bradley J.; Lee, Samuel K.

2014-12-01

234

Do general physics textbooks discuss scientists’ ideas about atomic structure? A case in Korea  

NASA Astrophysics Data System (ADS)

Research in science education has recognized the importance of teaching atomic structure within a history and philosophy of science perspective. The objective of this study is to evaluate general physics textbooks published in Korea based on the eight criteria developed in previous research. The result of this study shows that Korean general physics textbooks often lack detail about the history and philosophy of science. This result is quite similar to those published for the USA. Furthermore, chemistry textbooks published in the USA, Turkey and Venezuela are quite similar to the physics textbooks. This is a cause for concern as textbooks present theories as facts and ignore the historical reconstructions based on the development of scientific theories that frequently involve controversies and conflicts among scientists. The inclusion of historical reconstructions of ideas about atomic structure can provide students with a better appreciation of the dynamics of scientific progress.

Niaz, Mansoor; Kwon, Sangwoon; Kim, Nahyun; Lee, Gyoungho

2013-01-01

235

Symmetry and aesthetics in introductory physics: An experiment in interdisciplinary physics and fine arts education  

NASA Astrophysics Data System (ADS)

In a recent editorial in Physics Today (July, 2006, p. 10) the ability of physicists to "imagine new realities" was correlated with what have been traditionally considered non-scientific qualities of imagination and creativity, which are usually associated with fine arts. In view of the current developments in physics of the 21st Century, including the searches for cosmic dark energy and evidence from the Large Hadron Collider which, it is hoped, will verify or refute the proposals of String Theory, the importance of developing creativity and imagination through education is gaining recognition. Two questions are addressed by this study: First, How can we bring the sense of aesthetics and creativity, which are important in the practice of physics, into the teaching and learning of physics at the introductory college level, without sacrificing the mathematical rigor which is necessary for proper understanding of physics? Second, How can we provide access to physics for a diverse population of students which includes physics majors, arts majors, and future teachers? An interdisciplinary curriculum which begins with teaching math as a language of nature, and utilizes arts to help visualize the connections between mathematics and the physical universe, may provide answers to these questions. In this dissertation I describe in detail the case study of the eleven students - seven physics majors and four arts majors - who participated in an experimental course, Symmetry and Aesthetics in Introductory Physics, in Winter Quarter, 2007, at UCSB's College of Creative Studies. The very positive results of this experiment suggest that this model deserves further testing, and could provide an entry into the study of physics for physics majors, liberal arts majors, future teachers, and as a foundation for media arts and technology programs.

van der Veen, Janet Krause

236

Science Goals of the Primary Atomic Reference Clock in Space (PARCS) Experiment  

NASA Technical Reports Server (NTRS)

The PARCS (Primary Atomic Reference Clock in Space) experiment will use a laser-cooled Cesium atomic clock operating in the microgravity environment aboard the International Space Station (ISS) to provide both advanced tests of gravitational theory and to demonstrate a new cold-atom clock technology for space. PARCS is a joint project of the National Institute of Standards and Technology (NIST), NASA's Jet Propulsion Laboratory (JPL), and the University of Colorado (CU). This paper concentrates on the scientific goals of the PARCS mission. The microgravity space environment allows laser-cooled Cs atoms to have Ramsey times in excess of those feasible on Earth, resulting in improved clock performance. Clock stabilities of 5x10(exp -14) at one second, and accuracies better than 10(exp -16) are projected.

Ashby, N.

2003-01-01

237

Software for physics of tau lepton decay in LHC experiments  

E-print Network

Software development in high energy physics experiments offers unique experience with rapidly changing environment and variety of different standards and frameworks that software must be adapted to. As such, regular methods of software development are hard to use as they do not take into account how greatly some of these changes influence the whole structure. The following thesis summarizes development of TAUOLA C++ Interface introducing tau decays to new event record standard. Documentation of the program is already published. That is why it is not recalled here again. We focus on the development cycle and methodology used in the project, starting from the definition of the expectations through planning and designing the abstract model and concluding with the implementation. In the last part of the paper we present installation of the software within different experiments surrounding Large Hadron Collider and the problems that emerged during this process.

Tomasz Przedzinski

2010-09-20

238

Development of the Zeeman Slower for the Ultra-cold Atomic Interference Experiment  

E-print Network

that the Zeeman effect on the energy levels will continuously balance the changing observed energy of the photonsDevelopment of the Zeeman Slower for the Ultra-cold Atomic Interference Experiment Daniel Gochnauer of the Zeeman slower. Some discussion of other electromagnet coils, specifically the MOT coils, will also

Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

239

Physics of Hard Spheres Experiment (PhaSE) or "Making Jello in Space"  

NASA Technical Reports Server (NTRS)

The Physics of Hard Spheres Experiment (PHaSE) is a highly successful experiment that flew aboard two shuttle missions to study the transitions involved in the formation of jellolike colloidal crystals in a microgravity environment. A colloidal suspension, or colloid, consists of fine particles, often having complex interactions, suspended in a liquid. Paint, ink, and milk are examples of colloids found in everyday life. In low Earth orbit, the effective force of gravity is thousands of times less than at the Earth's surface. This provides researchers a way to conduct experiments that cannot be adequately performed in an Earth-gravity environment. In microgravity, colloidal particles freely interact without the complications of settling that occur in normal gravity on Earth. If the particle interactions within these colloidal suspensions could be predicted and accurately modeled, they could provide the key to understanding fundamental problems in condensed matter physics and could help make possible the development of wonderful new "designer" materials. Industries that make semiconductors, electro-optics, ceramics, and composites are just a few that may benefit from this knowledge. Atomic interactions determine the physical properties (e.g., weight, color, and hardness) of ordinary matter. PHaSE uses colloidal suspensions of microscopic solid plastic spheres to model the behavior of atomic interactions. When uniformly sized hard spheres suspended in a fluid reach a certain concentration (volume fraction), the particle-fluid mixture changes from a disordered fluid state, in which the spheres are randomly organized, to an ordered "crystalline" state, in which they are structured periodically. The thermal energy of the spheres causes them to form ordered arrays, analogous to crystals. Seven of the eight PHaSE samples ranged in volume fraction from 0.483 to 0.624 to cover the range of interest, while one sample, having a concentration of 0.019, was included for instrument calibration.

Ling, Jerri S.; Doherty, Michael P.

1998-01-01

240

Photoemission from solids: the transition from solid-state to atomic physics  

SciTech Connect

As the photon energy is increased, photoemission from solids undergoes a slow transition from solid-state to atomic behavior. However, throughout the energy range h..nu.. = 10 to 1000 eV or higher both types of phenomena are present. Thus angle-resolved photoemission can only be understood quantitatively if each experimenter recognizes the presence of band-structure, photoelectron diffraction, and photoelectron asymmetry effects. The quest for this understanding will build some interesting bridges between solid-state and atomic physics and should also yield important new insights about the phenomena associated with photoemission.

Shirley, D.A.

1980-08-01

241

The Advanced Light Source: A new tool for research in atomic and molecular physics  

SciTech Connect

The Advanced Light Source at the Lawrence Berkeley Laboratory will be the world's brightest synchrotron radiation source in the extreme ultraviolet and soft x-ray regions of the spectrum when it begins operation in 1993. It will be available as a national user facility to researchers in a broad range of disciplines, including materials science, atomic and molecular physics, chemistry, biology, imaging, and technology. The high brightness of the ALS will be particularly well suited to high-resolution studies of tenuous targets, such as excited atoms, ions, and clusters. 13 figs., 4 tabs.

Schlachter, F.; Robinson, A.

1991-04-01

242

Controlling ultracold atoms in multi-band optical lattices for simulation of Kondo physics  

E-print Network

We show that ultracold atoms can be controlled in multi-band optical lattices through spatially periodic Raman pulses for investigation of a class of strongly correlated physics related to the Kondo problem. The underlying dynamics of this system is described by a spin-dependent fermionic or bosonic Kondo-Hubbard lattice model even if we have only spin-independent atomic collision interaction. We solve the bosonic Kondo-Hubbard lattice model through a mean-field approximation, and the result shows a clear phase transition from the ferromagnetic superfluid to the Kondo-signet insulator at the integer filling.

L. -M. Duan

2003-10-16

243

PHYSICAL REVIEW A 82, 023419 (2010) Cooling atoms with a moving one-way barrier  

E-print Network

utility of a one-way barrier is best understood by its relationship to Maxwell's demon [14's famous thought experiment [21­23]. The demon uses the trap door to collect all the gas on one side functions in the same way as the demon and its trap door, allowing atoms traveling in only one direction

Steck, Daniel A.

244

Recent progress in applications of high energy ion beams to nuclear structure and atomic physics  

Microsoft Academic Search

We discuss some recent experiments at the Bevalac which demonstrate the usefulness of relativistic heavy ion beams for study of the nuclear structure of radioactive isotopes. This work was supported in part by the Director, Office of Energy Research, Division of Nuclear Physics of the Office of High Energy and Nuclear Physics of the U.S. Department of Energy under Contract

T. J. M. Symons

1986-01-01

245

PREFACE: Atomically controlled fabrication technology: new physics and functional device realization Atomically controlled fabrication technology: new physics and functional device realization  

NASA Astrophysics Data System (ADS)

To realize next generation functional devices, atomic level controllability of the application and fabrication techniques is necessary. The conventional route to advance solid state devices, which involves improvement of 'instrumental accuracy', is now facing a major paradigm shift towards 'phenomenal accuracy'. Therefore, to keep up with this critical turn in the development of devices, pioneering research (both theoretical and experimental) on relevant materials, focusing on new physics at the atomic scale, is inevitable. This special section contains articles on the advancements in fabrication of functional devices with an emphasis on the exploration, clarification and understanding of atomistic phenomena. Research articles reporting theoretical and experimental findings on various materials such as semiconductors, metals, magnetic and organic systems, collectively present and 'capture' the appropriate processes and mechanisms of this rapidly developing field. The theoretical investigations employ first-principles quantum-mechanical simulations to clarify and bring about design principles and guidelines, or to develop more reliable computational methods. Experimental studies, on the other hand, introduce novel capabilities to build, view and manipulate materials at the atomic scale by employing pioneering techniques. Thus, the section pays significant attention to novel structures and properties and the accompanying fabrication techniques and design arising from the understanding of properties and structures at the atomic scale. We hope that researchers in the area of physics, materials science and engineering, interested in the development of functional devices via atomic level control, will find valuable information in this collaborative work. We are grateful to all of the authors for their contributions. Atomically controlled fabrication contents On the mechanism of carbon nanotube formation: the role of the catalyst G N Ayre, T Uchino, B Mazumder, A L Hector, J L Hutchison, D C Smith, P Ashburn and C H de Groot Mechanism of atomic-scale passivation and flattening of semiconductor surfaces by wet-chemical preparationsKenta Arima, Katsuyoshi Endo, Kazuto Yamauchi, Kikuji Hirose, Tomoya Ono and Yasuhisa Sano Real-space calculations for electron transport properties of nanostructuresTomoya Ono, Shigeru Tsukamoto, Yoshiyuki Egami and Yoshitaka Fujimoto Thermally activated magnetization reversal in monatomic magnetic chains on surfaces studied by classical atomistic spin-dynamics simulationsDavid S G Bauer, Phivos Mavropoulos, Samir Lounis and Stefan Blügel An atomically controlled Si film formation process at low temperatures using atmospheric-pressure VHF plasmaK Yasutake, H Kakiuchi, H Ohmi, K Inagaki, Y Oshikane and M Nakano Single-nanometer focusing of hard x-rays by Kirkpatrick-Baez mirrorsKazuto Yamauchi, Hidekazu Mimura, Takashi Kimura, Hirokatsu Yumoto, Soichiro Handa, Satoshi Matsuyama, Kenta Arima, Yasuhisa Sano, Kazuya Yamamura, Koji Inagaki, Hiroki Nakamori, Jangwoo Kim, Kenji Tamasaku, Yoshinori Nishino, Makina Yabashi and Tetsuya Ishikawa Surface magnetism in O2 dissociation—from basics to applicationY Kunisada, M C Escaño and H Kasai Real-space finite-difference approach for multi-body systems: path-integral renormalization group method and direct energy minimization methodAkira Sasaki, Masashi Kojo, Kikuji Hirose and Hidekazu Goto Electrical conduction of organic ultrathin films evaluated by an independently driven double-tip scanning tunneling microscopeK Takami, S Tsuruta, Y Miyake, M Akai-Kasaya, A Saito, M Aono and Y Kuwahara

Kuwahara, Yuji; Kasai, Hideaki

2011-10-01

246

Position determination of fragile objects in nuclear physics experiments  

NASA Astrophysics Data System (ADS)

To study the single particle nature of unstable nuclei, inverse kinematics with radioactive beams in transfer reactions have to be used. In such experiments, it is important to determine the exact positions of the beam and detected particles. A Laser Based Alignment System (LBAS) has been successfully used in several nuclear physics experiments. LBAS is designed to determine positions of sharp edges with sub-millimeter accuracy without physical contact with the measured object. In the recent p(^34,46Ar,d) transfer experiments, the beam positions at the target are reconstructed with Channel Plate Detectors, the emitted deuteron particles are detected with the High Resolution Array (HiRA) and the recoil particles are measured with the S800 spectrometer. The HiRA device consists of multiple telescopes, each of which consists of 1024 pixels, with the dimension of 1.95x1.95mm^2 for each pixel. We use LBAS to determine the positions of the target, the channel plate detectors, and the pixels positions of HiRA. We then map these elements to the global positions of the S800 spectrometer and its magnetic elements.

Kit Cheung, Hoi; Tsang, M. Betty

2008-10-01

247

The role of the atom-cavity detuning in bimodal cavity experiments  

E-print Network

The coherent evolution of the atom-cavity state in bimodal (cavity) experiments has been analyzed for a realistic time-dependence in detuning the atomic transition frequency. Apart from a `smooth switch' of the atomic resonance from one to the second mode of a bimodal cavity, we considered also an additional (effective) interaction between the field modes of the cavity, known as `communication channel'. Comparison of our model computations has been made especially with the measurements by Rauschenbeutel et al., [2001 Phys. Rev. A 64 050301] who demonstrated for the first time the entanglement of the field modes in a bimodal cavity. It is shown that the agreement between the (theoretically) predicted and experimental phase shifts can be improved by allowing a `communication' between the two field modes during a short but finite switch of the atomic transition frequency from one mode to the other. We therefore suggest that the details of the atom-cavity detuning should be taken into account for the future interpretation of bimodal cavity experiments.

D. Gonta; S. Fritzsche

2007-11-13

248

Study to perform preliminary experiments to evaluate particle generation and characterization techniques for zero-gravity cloud physics experiments  

NASA Technical Reports Server (NTRS)

Methods of particle generation and characterization with regard to their applicability for experiments requiring cloud condensation nuclei (CCN) of specified properties were investigated. Since aerosol characterization is a prerequisite to assessing performance of particle generation equipment, techniques for characterizing aerosol were evaluated. Aerosol generation is discussed, and atomizer and photolytic generators including preparation of hydrosols (used with atomizers) and the evaluation of a flight version of an atomizer are studied.

Katz, U.

1982-01-01

249

Atomic Oxygen and Space Environment Effects on Aerospace Materials Flown with EOIM-3 Experiment  

NASA Technical Reports Server (NTRS)

Polymer materials samples mounted on a passive carrier tray were flown aboard the STS-46 Atlantis shuttle as complement to the EOIM-3 (Evaluation of Oxygen Interaction with Materials) experiment to evaluate the effects of atomic oxygen on the materials and to measure the gaseous shuttle bay environment. The morphological changes of the samples produced by the atomic oxygen fluence of 2.07 x 10(exp 20) atoms/cm(exp 2) are being reported. The changes have been verified using Electron Spectroscopy for Chemical Analysis (ESCA), gravimetric measurement, microscopic observations and thermo-optical measurements. The samples, including Kapton, Delrin, epoxies, Beta Cloth, Chemglaze Z306, silver Teflon, silicone coatings, 3M tape and Uralane and Ultem, PEEK, Victrex (PES), Polyethersulfone and Polymethylpentene thermoplastic, have been characterized by their oxygen reaction efficiency on the basis of their erosion losses and the oxygen fluence. Those efficiencies have been compared to results from other experiments, when available. The efficiencies of the samples are all in the range of E-24 g/atom. The results indicate that the reaction efficiencies of the reported materials can be grouped in about three ranges of values. The least affected materials which have efficiencies varying from 1 to 10(exp 25) g/atom, include silicones, epoxies, Uralane and Teflon. A second group with efficiency from 10 to 45(exp 25) g/atom includes additional silicone coatings, the Chemglaze Z306 paint and Kapton. The third range from 50 to 75(exp 25) includes organic compound such as Pentene, Peek, Ultem, Sulfone and a 3M tape. A Delrin sample had the highest reaction efficiency of 179(exp 25) g/atom. Two samples, the aluminum Beta cloth X389-7 and the epoxy fiberglass G-11 nonflame retardant, showed a slight mass increase.

Scialdone, John J.; Clatterbuck, Carroll H.; Ayres-Treusdell, Mary; Park, Gloria; Kolos, Diane

1996-01-01

250

Unpacking Gender Differences in Students' Perceived Experiences in Introductory Physics  

NASA Astrophysics Data System (ADS)

Prior research has shown, at our institution: 1) males outperform females on conceptual assessments (a gender gap), 2) the gender gap persists despite the use of research-based reforms, and 3) the gender gap is correlated with students' physics and mathematics background and prior attitudes and beliefs [Kost, et al. PRST-PER, 5, 010101]. Our follow-up work begins to explore how males and females experience the introductory course differently and how these differences relate to the gender gap. We gave a survey to students in the introductory course in which we investigated students' physics identity and self-efficacy. We find there are significant gender differences in each of these three areas, and further find that these measures are weakly correlated with student conceptual performance, and moderately correlated with course grade.

Kost, Lauren E.; Pollock, Steven J.; Finkelstein, Noah D.

2009-11-01

251

Tokamak Physics Experiment (TPX) power supply design and development  

SciTech Connect

The Tokamak Physics Experiment (TPX) is an advanced tokamak project aimed at the production of quasi-steady state plasmas with advanced shape, heating, and particle control. TPX is to be built at the Princeton Plasma Physics Laboratory (PPPL) using many of the facilities from the Tokamak Fusion Test Reactor (TFTR). TPX will be the first tokamak to utilize superconducting (SC) magnets in both the toroidal field (TF) and poloidal field (PF) systems. This new feature requires a departure from the traditional tokamak power supply schemes. This paper describes the plan for the adaptation of the PPPL/FTR power system facilities to supply TPX. Five major areas are addressed, namely the AC power system, the TF, PF and Fast Plasma Position Control (FPPC) power supplies, and quench protection for the TF and PF systems. Special emphasis is placed on the development of new power supply and protection schemes.

Neumeyer, C. [Raytheon Engineers and Constructors, Princeton, NJ (United States). EBASCO Div.; Bronner, G.; Lu, E.; Ramakrishnan, S. [Princeton Univ., NJ (United States). Plasma Physics Lab.

1995-04-01

252

Physical and chemical evidence for metallofullerenes with metal atoms as part of the cage  

NASA Astrophysics Data System (ADS)

SINCE the discovery of fullerenes1, efforts have been made to trap metal atoms inside fullerene cages2, and both endohedral3,4 and exohedral5,6 metallofullerenes have been synthesized. There is, however, a third possibility: a 'networked' metallofullerene, where the metal atom is incorporated into the carbon cage. Here we report the results of experiments to study the structure and reactivity of gas-phase fullerenes doped with niobium (NbCn+ with n = 28-50). These experiments, which use injected-ion drift-tube tech-niques, indicate that for fullerenes containing an even number of carbon atoms the metal is endohedral, but for fullerenes with an odd number of carbon atoms, the niobium metal is bound as a part of the carbon cage. Thus, networked metallofullerenes appear to be a stable class of metallofullerene. We suggest that such metallo-fullerenes can form if the metal atom retains sufficient electron density to form several strong covalent metal-carbon bonds.

Clemmer, David E.; Hunter, Joanna M.; Shelimov, Konstantin B.; Jarrold, Martin F.

1994-11-01

253

Physical mechanism of the Schwarzschild effect in film dosimetry—theoretical model and comparison with experiments  

NASA Astrophysics Data System (ADS)

In consideration of the importance of film dosimetry for the dosimetric verification of IMRT treatment plans, the Schwarzschild effect or failure of the reciprocity law, i.e. the reduction of the net optical density under 'protraction' or 'fractionation' conditions at constant dose, has been experimentally studied for Kodak XOMAT-V (Martens et al 2002 Phys. Med. Biol. 47 2221-34) and EDR 2 dosimetry films (Djouguela et al 2005 Phys. Med. Biol. 50 N317-N321). It is known that this effect results from the competition between two solid-state physics reactions involved in the latent-image formation of the AgBr crystals, the aggregation of two Ag atoms freshly formed from Ag+ ions near radiation-induced occupied electron traps and the spontaneous decomposition of the Ag atoms. In this paper, we are developing a mathematical model of this mechanism which shows that the interplay of the mean lifetime ? of the Ag atoms with the time pattern of the irradiation determines the magnitude of the observed effects of the temporal dose distribution on the net optical density. By comparing this theory with our previous protraction experiments and recent fractionation experiments in which the duration of the pause between fractions was varied, a value of the time constant ? of roughly 10 s at room temperature has been determined for EDR 2. The numerical magnitude of the Schwarzschild effect in dosimetry films under the conditions generally met in radiotherapy amounts to only a few per cent of the net optical density (net OD), so that it can frequently be neglected from the viewpoint of clinical applications. But knowledge of the solid-state physical mechanism and a description in terms of a mathematical model involving a typical time constant of about 10 s are now available to estimate the magnitude of the effect should the necessity arise, i.e. in cases of large fluctuations of the temporal pattern of film exposure.

Djouguela, A.; Kollhoff, R.; Rühmann, A.; Willborn, K. C.; Harder, D.; Poppe, B.

2006-09-01

254

The International Reactor Physics Experiment Evaluation Project (IRPHEP)  

SciTech Connect

Since the beginning of the Nuclear Power industry, numerous experiments concerned with nuclear energy and technology have been performed at different research laboratories, worldwide. These experiments required a large investment in terms of infrastructure, expertise, and cost; however, many were performed without a high degree of attention to archival of results for future use. The degree and quality of documentation varies greatly. There is an urgent need to preserve integral reactor physics experimental data, including measurement methods, techniques, and separate or special effects data for nuclear energy and technology applications and the knowledge and competence contained therein. If the data are compromised, it is unlikely that any of these experiments will be repeated again in the future. The International Reactor Physics Evaluation Project (IRPhEP) was initiated, as a pilot activity in 1999 by the by the Organization of Economic Cooperation and Development (OECD) Nuclear Energy Agency (NEA) Nuclear Science Committee (NSC). The project was endorsed as an official activity of the NSC in June of 2003. The purpose of the IRPhEP is to provide an extensively peer reviewed set of reactor physics related integral benchmark data that can be used by reactor designers and safety analysts to validate the analytical tools used to design next generation reactors and establish the safety basis for operation of these reactors. A short history of the IRPhEP is presented and its purposes are discussed in this paper. Accomplishments of the IRPhEP, including the first publication of the IRPhEP Handbook, are highlighted and the future of the project outlined.

J. Blair Briggs; Enrico Sartori; Lori Scott

2006-09-01

255

Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics  

SciTech Connect

The Large Hadron Collider (LHC) at CERN promises a major step forward in the understanding of the fundamental nature of matter. The ATLAS experiment is a general-purpose detector for the LHC, whose design was guided by the need to accommodate the wide spectrum of possible physics signatures. The major remit of the ATLAS experiment is the exploration of the TeV mass scale where groundbreaking discoveries are expected. In the focus are the investigation of the electroweak symmetry breaking and linked to this the search for the Higgs boson as well as the search for Physics beyond the Standard Model. In this report a detailed examination of the expected performance of the ATLAS detector is provided, with a major aim being to investigate the experimental sensitivity to a wide range of measurements and potential observations of new physical processes. An earlier summary of the expected capabilities of ATLAS was compiled in 1999 [1]. A survey of physics capabilities of the CMS detector was published in [2]. The design of the ATLAS detector has now been finalised, and its construction and installation have been completed [3]. An extensive test-beam programme was undertaken. Furthermore, the simulation and reconstruction software code and frameworks have been completely rewritten. Revisions incorporated reflect improved detector modelling as well as major technical changes to the software technology. Greatly improved understanding of calibration and alignment techniques, and their practical impact on performance, is now in place. The studies reported here are based on full simulations of the ATLAS detector response. A variety of event generators were employed. The simulation and reconstruction of these large event samples thus provided an important operational test of the new ATLAS software system. In addition, the processing was distributed world-wide over the ATLAS Grid facilities and hence provided an important test of the ATLAS computing system - this is the origin of the expression 'CSC studies' ('computing system commissioning'), which is occasionally referred to in these volumes. The work reported does generally assume that the detector is fully operational, and in this sense represents an idealised detector: establishing the best performance of the ATLAS detector with LHC proton-proton collisions is a challenging task for the future. The results summarised here therefore represent the best estimate of ATLAS capabilities before real operational experience of the full detector with beam. Unless otherwise stated, simulations also do not include the effect of additional interactions in the same or other bunch-crossings, and the effect of neutron background is neglected. Thus simulations correspond to the low-luminosity performance of the ATLAS detector. This report is broadly divided into two parts: firstly the performance for identification of physics objects is examined in detail, followed by a detailed assessment of the performance of the trigger system. This part is subdivided into chapters surveying the capabilities for charged particle tracking, each of electron/photon, muon and tau identification, jet and missing transverse energy reconstruction, b-tagging algorithms and performance, and finally the trigger system performance. In each chapter of the report, there is a further subdivision into shorter notes describing different aspects studied. The second major subdivision of the report addresses physics measurement capabilities, and new physics search sensitivities. Individual chapters in this part discuss ATLAS physics capabilities in Standard Model QCD and electroweak processes, in the top quark sector, in b-physics, in searches for Higgs bosons, supersymmetry searches, and finally searches for other new particles predicted in more exotic models.

Aad, G.; Abat, E.; Abbott, B.; Abdallah, J.; Abdelalim, A.A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Acharya, Bobby Samir; Adams, D.L.; Addy, T.N.; Adorisio, C.; Adragna, P.; Adye, T.; Aguilar-Saavedra, J.A.; Aharrouche, M.; Ahlen, S.P.; Ahles, F.; Ahmad, A.; /SUNY, Albany /Alberta U. /Ankara U. /Annecy, LAPP /Argonne /Arizona U. /Texas U., Arlington /Athens U. /Natl. Tech. U., Athens /Baku, Inst. Phys. /Barcelona, IFAE /Belgrade U. /VINCA Inst. Nucl. Sci., Belgrade /Bergen U. /LBL, Berkeley /Humboldt U., Berlin /Bern U., LHEP /Birmingham U. /Bogazici U. /INFN, Bologna /Bologna U.

2011-11-28

256

Comparison of Numerical Simulations to Experiments for Atomization in a Jet Nebulizer  

PubMed Central

The development of jet nebulizers for medical purposes is an important challenge of aerosol therapy. The performance of a nebulizer is characterized by its output rate of droplets with a diameter under 5 µm. However the optimization of this parameter through experiments has reached a plateau. The purpose of this study is to design a numerical model simulating the nebulization process and to compare it with experimental data. Such a model could provide a better understanding of the atomization process and the parameters influencing the nebulizer output. A model based on the Updraft nebulizer (Hudson) was designed with ANSYS Workbench. Boundary conditions were set with experimental data then transient 3D calculations were run on a 4 µm mesh with ANSYS Fluent. Two air flow rate (2 L/min and 8 L/min, limits of the operating range) were considered to account for different turbulence regimes. Numerical and experimental results were compared according to phenomenology and droplet size. The behavior of the liquid was compared to images acquired through shadowgraphy with a CCD Camera. Three experimental methods, laser diffractometry, phase Doppler anemometry (PDA) and shadowgraphy were used to characterize the droplet size distributions. Camera images showed similar patterns as numerical results. Droplet sizes obtained numerically are overestimated in relation to PDA and diffractometry, which only consider spherical droplets. However, at both flow rates, size distributions extracted from numerical image processing were similar to distributions obtained from shadowgraphy image processing. The simulation then provides a good understanding and prediction of the phenomena involved in the fragmentation of droplets over 10 µm. The laws of dynamics apply to droplets down to 1 µm, so we can assume the continuity of the distribution and extrapolate the results for droplets between 1 and 10 µm. So, this model could help predicting nebulizer output with defined geometrical and physical parameters. PMID:24244334

Lelong, Nicolas; Vecellio, Laurent; Sommer de Gélicourt, Yann; Tanguy, Christian; Diot, Patrice; Junqua-Moullet, Alexandra

2013-01-01

257

Comparison of numerical simulations to experiments for atomization in a jet nebulizer.  

PubMed

The development of jet nebulizers for medical purposes is an important challenge of aerosol therapy. The performance of a nebulizer is characterized by its output rate of droplets with a diameter under 5 µm. However the optimization of this parameter through experiments has reached a plateau. The purpose of this study is to design a numerical model simulating the nebulization process and to compare it with experimental data. Such a model could provide a better understanding of the atomization process and the parameters influencing the nebulizer output. A model based on the Updraft nebulizer (Hudson) was designed with ANSYS Workbench. Boundary conditions were set with experimental data then transient 3D calculations were run on a 4 µm mesh with ANSYS Fluent. Two air flow rate (2 L/min and 8 L/min, limits of the operating range) were considered to account for different turbulence regimes. Numerical and experimental results were compared according to phenomenology and droplet size. The behavior of the liquid was compared to images acquired through shadowgraphy with a CCD Camera. Three experimental methods, laser diffractometry, phase Doppler anemometry (PDA) and shadowgraphy were used to characterize the droplet size distributions. Camera images showed similar patterns as numerical results. Droplet sizes obtained numerically are overestimated in relation to PDA and diffractometry, which only consider spherical droplets. However, at both flow rates, size distributions extracted from numerical image processing were similar to distributions obtained from shadowgraphy image processing. The simulation then provides a good understanding and prediction of the phenomena involved in the fragmentation of droplets over 10 µm. The laws of dynamics apply to droplets down to 1 µm, so we can assume the continuity of the distribution and extrapolate the results for droplets between 1 and 10 µm. So, this model could help predicting nebulizer output with defined geometrical and physical parameters. PMID:24244334

Lelong, Nicolas; Vecellio, Laurent; Sommer de Gélicourt, Yann; Tanguy, Christian; Diot, Patrice; Junqua-Moullet, Alexandra

2013-01-01

258

Getting Ready for Physics - Commissioning of the ALICE Experiment  

E-print Network

ALICE at CERN-LHC is an experiment dedicated to the study of high-energy heavy-ion collision. In this paper we will briefly describe the experimental layout and give an overview on the installation status of the ALICE detector components including an outlook towards the completion of the staged detector setup. We will review the commissioning of the detector components with emphasis on the central detectors, in particular the time projection chamber (TPC). The commissioning took place in summer 2008 awaiting the first beams from the LHC in the fall. The result from commissioning are compared with the performance figures, which are outlined in the ALICE Physics Performance Reports.

H. R. Schmidt; for the ALICE Experiment

2009-05-27

259

Neutrino Oscillation Physics Potential of the T2K Experiment  

E-print Network

The observation of the recent electron neutrino appearance in a muon neutrino beam and the high-precision measurement of the mixing angle $\\theta_{13}$ have led to a re-evaluation of the physics potential of the T2K long-baseline neutrino oscillation experiment. Sensitivities are explored for CP violation in neutrinos, non-maximal $\\sin^22\\theta_{23}$, the octant of $\\theta_{23}$, and the mass hierarchy, in addition to the measurements of $\\delta_{CP}$, $\\sin^2\\theta_{23}$, and $\\Delta m^2_{32}$, for various combinations of $\

Abe, K; Aihara, H; Akiri, T; Andreopoulos, C; Aoki, S; Ariga, A; Assylbekov, S; Autiero, D; Barbi, M; Barker, G J; Barr, G; Bass, M; Batkiewicz, M; Bay, F; Berardi, V; Berger, B E; Berkman, S; Bhadra, S; Blaszczyk, F d M; Blondel, A; Bojechko, C; Bordoni, S; Boyd, S B; Brailsford, D; Bravar, A; Bronner, C; Buchanan, N; Calland, R G; Rodr'iguez, J Caravaca; Cartwright, S L; Castillo, R; Catanesi, M G; Cervera, A; Cherdack, D; Christodoulou, G; Clifton, A; Coleman, J; Coleman, S J; Collazuol, G; Connolly, K; Cremonesi, L; Dabrowska, A; Danko, I; Das, R; Davis, S; de Perio, P; De Rosa, G; Dealtry, T; Dennis, S R; Densham, C; Dewhurst, D; Di Lodovico, F; Di Luise, S; Drapier, O; Duboyski, T; Duffy, K; Dumarchez, J; Dytman, S; Dziewiecki, M; Emery-Schrenk, S; Ereditato, A; Escudero, L; Finch, A J; Friend, M; Fujii, Y; Fukuda, Y; Furmanski, A P; Galymov, V; Giffin, S; Giganti, C; Gilje, K; Goeldi, D; Golan, T; Gonin, M; Grant, N; Gudin, D; Hadley, D R; Haesler, A; Haigh, M D; Hamilton, P; Hansen, D; Hara, T; Hartz, M; Hasegawa, T; Hastings, N C; Hayato, Y; Hearty, C; Helmer, R L; Hierholzer, M; Hignight, J; Hillairet, A; Himmel, A; Hiraki, T; Hirota, S; Holeczek, J; Horikawa, S; Huang, K; Ichikawa, A K; Ieki, K; Ieva, M; Ikeda, M; Imber, J; Insler, J; Irvine, T J; Ishida, T; Ishii, T; Iwai, E; Iwamoto, K; Iyogi, K; Izmaylov, A; Jacob, A; Jamieson, B; Johnson, R A; Johnson, S; Jo, J H; Jonsson, P; Jung, C K; Kabirnezhad, M; Kaboth, A C; Kajita, T; Kakuno, H; Kameda, J; Kanazawa, Y; Karlen, D; Karpikov, I; Katori, T; Kearns, E; Khabibullin, M; Khotjantsev, A; Kielczewska, D; Kikawa, T; Kilinski, A; Kim, J; King, S; Kisiel, J; Kitching, P; Kobayashi, T; Koch, L; Kolaceke, A; Konaka, A; Kormos, L L; Korzenev, A; Koseki, K; Koshio, Y; Kropp, W; Kubo, H; Kudenko, Y; Kurjata, R; Kutter, T; Lagoda, J; Laihem, K; Lamont, I; Larkin, E; Laveder, M; Lawe, M; Lazos, M; Lindner, T; Lister, C; Litchfield, R P; Longhin, A; Ludovici, L; Magaletti, L; Mahn, K; Malek, M; Manly, S; Marino, A D; Marteau, J; Martin, J F; Martynenko, S; Maruyama, T; Matveev, V; Mavrokoridis, K; Mazzucato, E; McCarthy, M; McCauley, N; McFarland, K S; McGrew, C; Mefodiev, A; Metelko, C; Mezzetto, M; Mijakowski, P; Miller, C A; Minamino, A; Mineev, O; Missert, A; Miura, M; Moriyama, S; Mueller, Th A; Murakami, A; Murdoch, M; Murphy, S; Myslik, J; Nakadaira, T; Nakahata, M; Nakamura, K; Nakayama, S; Nakaya, T; Nakayoshi, K; Nielsen, C; Nirkko, M; Nishikawa, K; Nishimura, Y; O'Keeffe, H M; Ohta, R; Okumura, K; Okusawa, T; Oryszczak, W; Oser, S M; Ovsyannikova, T; Owen, R A; Oyama, Y; Palladino, V; Palomino, J L; Paolone, V; Payne, D; Perevozchikov, O; Perkin, J D; Petrov, Y; Pickard, L; Guerra, E S Pinzon; Pistillo, C; Plonski, P; Poplawska, E; Popov, B; Posiadala-Zezula, M; Poutissou, J -M; Poutissou, R; Przewlocki, P; Quilain, B; Radicioni, E; Ratoff, P N; Ravonel, M; Rayner, M A M; Redij, A; Reeves, M; Reinherz-Aronis, E; Riccio, C; Rodrigues, P A; Rojas, P; Rondio, E; Roth, S; Rubbia, A; Ruterbories, D; Sacco, R; Sakashita, K; S'anchez, F; Sato, F; Scantamburlo, E; Scholberg, K; Schoppmann, S; Schwehr, J; Scott, M; Seiya, Y; Sekiguchi, T; Sekiya, H; Sgalaberna, D; Shaker, F; Shiozawa, M; Short, S; Shustrov, Y; Sinclair, P; Smith, B; Smy, M; Sobczyk, J T; Sobel, H; Sorel, M; Southwell, L; Stamoulis, P; Steinmann, J; Still, B; Suda, Y; Suzuki, A; Suzuki, K; Suzuki, S Y; Suzuki, Y; Tacik, R; Tada, M; Takahashi, S; Takeda, A; Takeuchi, Y; Tanaka, H K; Tanaka, H A; Tanaka, M M; Terhorst, D; Terri, R; Thompson, L F; Thorley, A; Tobayama, S; Toki, W; Tomura, T; Totsuka, Y; Touramanis, C; Tsukamoto, T; Tzanov, M; Uchida, Y; Vacheret, A; Vagins, M; Vasseur, G; Wachala, T; Waldron, A V; Walter, C W; Wark, D; Wascko, M O; Weber, A; Wendell, R; Wilkes, R J; Wilking, M J; Wilkinson, C; Williamson, Z; Wilson, J R; Wilson, R J; Wongjirad, T; Yamada, Y; Yamamoto, K; Yanagisawa, C; Yano, T; Yen, S; Yershov, N; Yokoyama, M; Yuan, T; Yu, M; Zalewska, A; Zalipska, J; Zambelli, L; Zaremba, K; Ziembicki, M; Zimmerman, E D; Zito, M; Zmuda, J

2014-01-01

260

Neutrino Oscillation Physics Potential of the T2K Experiment  

E-print Network

The observation of the recent electron neutrino appearance in a muon neutrino beam and the high-precision measurement of the mixing angle $\\theta_{13}$ have led to a re-evaluation of the physics potential of the T2K long-baseline neutrino oscillation experiment. Sensitivities are explored for CP violation in neutrinos, non-maximal $\\sin^22\\theta_{23}$, the octant of $\\theta_{23}$, and the mass hierarchy, in addition to the measurements of $\\delta_{CP}$, $\\sin^2\\theta_{23}$, and $\\Delta m^2_{32}$, for various combinations of $\

K. Abe; J. Adam; H. Aihara; T. Akiri; C. Andreopoulos; S. Aoki; A. Ariga; S. Assylbekov; D. Autiero; M. Barbi; G. J. Barker; G. Barr; M. Bass; M. Batkiewicz; F. Bay; V. Berardi; B. E. Berger; S. Berkman; S. Bhadra; F. d. M. Blaszczyk; A. Blondel; C. Bojechko; S. Bordoni; S. B. Boyd; D. Brailsford; A. Bravar; C. Bronner; N. Buchanan; R. G. Calland; J. Caravaca Rodr'iguez; S. L. Cartwright; R. Castillo; M. G. Catanesi; A. Cervera; D. Cherdack; G. Christodoulou; A. Clifton; J. Coleman; S. J. Coleman; G. Collazuol; K. Connolly; L. Cremonesi; A. Dabrowska; I. Danko; R. Das; S. Davis; P. de Perio; G. De Rosa; T. Dealtry; S. R. Dennis; C. Densham; D. Dewhurst; F. Di Lodovico; S. Di Luise; O. Drapier; T. Duboyski; K. Duffy; J. Dumarchez; S. Dytman; M. Dziewiecki; S. Emery-Schrenk; A. Ereditato; L. Escudero; A. J. Finch; M. Friend; Y. Fujii; Y. Fukuda; A. P. Furmanski; V. Galymov; S. Giffin; C. Giganti; K. Gilje; D. Goeldi; T. Golan; M. Gonin; N. Grant; D. Gudin; D. R. Hadley; A. Haesler; M. D. Haigh; P. Hamilton; D. Hansen; T. Hara; M. Hartz; T. Hasegawa; N. C. Hastings; Y. Hayato; C. Hearty; R. L. Helmer; M. Hierholzer; J. Hignight; A. Hillairet; A. Himmel; T. Hiraki; S. Hirota; J. Holeczek; S. Horikawa; K. Huang; A. K. Ichikawa; K. Ieki; M. Ieva; M. Ikeda; J. Imber; J. Insler; T. J. Irvine; T. Ishida; T. Ishii; E. Iwai; K. Iwamoto; K. Iyogi; A. Izmaylov; A. Jacob; B. Jamieson; R. A. Johnson; S. Johnson; J. H. Jo; P. Jonsson; C. K. Jung; M. Kabirnezhad; A. C. Kaboth; T. Kajita; H. Kakuno; J. Kameda; Y. Kanazawa; D. Karlen; I. Karpikov; T. Katori; E. Kearns; M. Khabibullin; A. Khotjantsev; D. Kielczewska; T. Kikawa; A. Kilinski; J. Kim; S. King; J. Kisiel; P. Kitching; T. Kobayashi; L. Koch; A. Kolaceke; A. Konaka; L. L. Kormos; A. Korzenev; K. Koseki; Y. Koshio; W. Kropp; H. Kubo; Y. Kudenko; R. Kurjata; T. Kutter; J. Lagoda; K. Laihem; I. Lamont; E. Larkin; M. Laveder; M. Lawe; M. Lazos; T. Lindner; C. Lister; R. P. Litchfield; A. Longhin; L. Ludovici; L. Magaletti; K. Mahn; M. Malek; S. Manly; A. D. Marino; J. Marteau; J. F. Martin; S. Martynenko; T. Maruyama; V. Matveev; K. Mavrokoridis; E. Mazzucato; M. McCarthy; N. McCauley; K. S. McFarland; C. McGrew; A. Mefodiev; C. Metelko; M. Mezzetto; P. Mijakowski; C. A. Miller; A. Minamino; O. Mineev; A. Missert; M. Miura; S. Moriyama; Th. A. Mueller; A. Murakami; M. Murdoch; S. Murphy; J. Myslik; T. Nakadaira; M. Nakahata; K. Nakamura; S. Nakayama; T. Nakaya; K. Nakayoshi; C. Nielsen; M. Nirkko; K. Nishikawa; Y. Nishimura; H. M. O'Keeffe; R. Ohta; K. Okumura; T. Okusawa; W. Oryszczak; S. M. Oser; T. Ovsyannikova; R. A. Owen; Y. Oyama; V. Palladino; J. L. Palomino; V. Paolone; D. Payne; O. Perevozchikov; J. D. Perkin; Y. Petrov; L. Pickard; E. S. Pinzon Guerra; C. Pistillo; P. Plonski; E. Poplawska; B. Popov; M. Posiadala-Zezula; J. -M. Poutissou; R. Poutissou; P. Przewlocki; B. Quilain; E. Radicioni; P. N. Ratoff; M. Ravonel; M. A. M. Rayner; A. Redij; M. Reeves; E. Reinherz-Aronis; C. Riccio; P. A. Rodrigues; P. Rojas; E. Rondio; S. Roth; A. Rubbia; D. Ruterbories; R. Sacco; K. Sakashita; F. S'anchez; F. Sato; E. Scantamburlo; K. Scholberg; S. Schoppmann; J. Schwehr; M. Scott; Y. Seiya; T. Sekiguchi; H. Sekiya; D. Sgalaberna; F. Shaker; M. Shiozawa; S. Short; Y. Shustrov; P. Sinclair; B. Smith; M. Smy; J. T. Sobczyk; H. Sobel; M. Sorel; L. Southwell; P. Stamoulis; J. Steinmann; B. Still; Y. Suda; A. Suzuki; K. Suzuki; S. Y. Suzuki; Y. Suzuki; R. Tacik; M. Tada; S. Takahashi; A. Takeda; Y. Takeuchi; H. K. Tanaka; H. A. Tanaka; M. M. Tanaka; D. Terhorst; R. Terri; L. F. Thompson; A. Thorley; S. Tobayama; W. Toki; T. Tomura; Y. Totsuka; C. Touramanis; T. Tsukamoto; M. Tzanov; Y. Uchida; A. Vacheret; M. Vagins; G. Vasseur; T. Wachala; A. V. Waldron; C. W. Walter; D. Wark; M. O. Wascko; A. Weber; R. Wendell; R. J. Wilkes; M. J. Wilking; C. Wilkinson; Z. Williamson; J. R. Wilson; R. J. Wilson; T. Wongjirad; Y. Yamada; K. Yamamoto; C. Yanagisawa; T. Yano; S. Yen; N. Yershov; M. Yokoyama; T. Yuan; M. Yu; A. Zalewska; J. Zalipska; L. Zambelli; K. Zaremba; M. Ziembicki; E. D. Zimmerman; M. Zito; J. Zmuda

2014-09-26

261

Report on Physics of Channelization: Theory, Experiment, and Observation  

SciTech Connect

The project involved a study of physical processes that create eroded channel and drainage networks. A particular focus was on how the shape of the channels and the network depended on the nature of the fluid flow. Our approach was to combine theoretical, experimental, and observational studies in close collaboration with Professor Daniel Rothman of the Massachusetts Institute of Technology. Laboratory -scaled experiments were developed and quantitative data on the shape of the pattern and erosion dynamics are obtained with a laser-aided topography technique and fluorescent optical imaging techniques.

Kudrolli, Arshad [Clark University] [Clark University

2014-05-19

262

Preliminary Safety Analysis Report for the Tokamak Physics Experiment  

SciTech Connect

This Preliminary Safety Analysis Report (PSAR), includes an indication of the magnitude of facility hazards, complexity of facility operations, and the stage of the facility life-cycle. It presents the results of safety analyses, safety assurance programs, identified vulnerabilities, compensatory measures, and, in general, the rationale describing why the Tokamak Physics Experiment (TPX) can be safely operated. It discusses application of the graded approach to the TPX safety analysis, including the basis for using Department of Energy (DOE) Order 5480.23 and DOE-STD-3009-94 in the development of the PSAR.

Motloch, C.G.; Bonney, R.F. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States); Levine, J.D. [Princeton Univ., NJ (United States). Plasma Physics Lab.; McKenzie-Carter, M.A. [Science Applications International Corp., San Diego, CA (United States); Masson, L.S. [SCIENTECH, Inc., Idaho Falls, ID (United States); Commander, J.C.

1995-04-01

263

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics  

PubMed Central

Since their development in the late 1980s, cheap, reliable external cavity diode lasers (ECDLs) have replaced complex and expensive traditional dye and Titanium Sapphire lasers as the workhorse laser of atomic physics labs1,2. Their versatility and prolific use throughout atomic physics in applications such as absorption spectroscopy and laser cooling1,2 makes it imperative for incoming students to gain a firm practical understanding of these lasers. This publication builds upon the seminal work by Wieman3, updating components, and providing a video tutorial. The setup, frequency locking and performance characterization of an ECDL will be described. Discussion of component selection and proper mounting of both diodes and gratings, the factors affecting mode selection within the cavity, proper alignment for optimal external feedback, optics setup for coarse and fine frequency sensitive measurements, a brief overview of laser locking techniques, and laser linewidth measurements are included. PMID:24796259

Hardman, Kyle S.; Bennetts, Shayne; Debs, John E.; Kuhn, Carlos C. N.; McDonald, Gordon D.; Robins, Nick

2014-01-01

264

Active optical fibres in modern particle physics experiments  

E-print Network

In modern particle physics experiments wavelength-shifting and scintillating fibres based on plastic polymers are used for tracking and calorimetry. In this review the role of photon trapping efficiencies, transmission functions and signal response times for common multimode active fibres is discussed. Numerical simulations involving three dimensional tracking of skew rays through curved fibres demonstrate the characteristics of trapped light. Of practical interest are the parametrisations of transmission functions and the minimum permissible radius of curvature. These are of great importance in today's experiments where high count rates and small numbers of photoelectrons are encountered. Special emphasis has been placed on the timing resolution of fibre detectors and its limitation due to variations in the path length of generated photons.

C. P. Achenbach

2004-04-05

265

Comparison between experiments and predictions based on maximum entropy for sprays from a pressure atomizer  

NASA Astrophysics Data System (ADS)

Measurements were made of the droplet size and velocity distributions in a hollow cone spray from a pressure atomizer using a phase/Doppler particle analyzer. The maximum entropy principle is used to predict these distributions. The constraints imposed in this model involve conversation of mass, momentum, and energy. Estimates of the source terms associated with these constraints are made based on physical reasoning. Agreement between the measurements and the predictions is very good.

Li, X.; Chin, L. P.; Tankin, R. S.; Jackson, T.; Stutrud, J.; Switzer, G.

1991-07-01

266

Atomic physics with highly charged ions: Progress report, 15 August 1985--14 August 1988  

SciTech Connect

The study of inelastic collision phenomena with highly charged projectile ions and the interpretation of spectral features resulting from these collisions remain as the major focal points in the atomic physics research at the J.R. Macdonald Laboratory, Kansas State University, Manhattan, Kansas. The title of the research project ''Atomic Physics with Highly Charged Ions'' speaks to these points. The experimental work is made possible locally by the use of relatively high velocity, highly charged projectiles (v typically 5% c) as obtained from the 6 MV tandem Van de Graaff accelerator. The work in the past few years has divided into collisions at high velocity using the primary beams from the accelerator and collisions at low velocity using secondary beams (recoil ions produced in a high velocity collision) in a so-called SIRS (Secondary Ion Recoil Source) geometry. Theoretical calculations have been performed to accurately describe inelastic scattering processes of the one-electron and many-electron type, and to accurately predict atomic transition energies and intensities for x-rays and Auger electrons. Correlation effects and polarization phenomena in ion-atom collisions have been investigated.

Richard, P.

1988-08-01

267

Options for a next-generation spheromak physics experiment  

NASA Astrophysics Data System (ADS)

SSPX experiments and resistive MHD modeling suggest options for a next-generation experiment. Magnetic fluctuations are now <1% when the q-profile does not cross low-order rational surfaces in the spheromak core, yielding good energy confinement.^1 Plasma current and magnetic field decay slowly; initial experiments suggest that the they can be rebuilt periodically by high current pulses.^2 Modeling predicts that flux amplification, typically 2-3 in SSPX, can be increased to >50 by actively reducing the bias (``ABR'') after spheromak formation, reducing edge ohmic losses proportionally. ABR is also predicted to improve stability and energy confinement. Neutral-beam experiments planned for SSPX^3 may provide a path to hotter plasmas. Next-generation spheromak geometries and scenarios building on these results are described to improve plasma parameters, explore additional stability control, and examine other physics issues. Work supported by U.S. DOE under Contract No. W-7405-ENG-48 at UC LLNL. ^1H. S. McLean, et al., Phys. Plasmas 13, 056105 (2006). ^2S. Woodruff, et al., Phys. Rev. Letters 93, 205002 (2004). ^3D..N. Hill, et al., this meeting.

Hooper, E. B.; Cohen, B. I.; Hill, D. N.; McLean, H. S.; Romero-Talamás, C. A.; Wood, R. D.

2006-10-01

268

Virtual experiments, physical validation: dental morphology at the intersection of experiment and theory.  

PubMed

Computational models such as finite-element analysis offer biologists a means of exploring the structural mechanics of biological systems that cannot be directly observed. Validated against experimental data, a model can be manipulated to perform virtual experiments, testing variables that are hard to control in physical experiments. The relationship between tooth form and the ability to break down prey is key to understanding the evolution of dentition. Recent experimental work has quantified how tooth shape promotes fracture in biological materials. We present a validated finite-element model derived from physical compression experiments. The model shows close agreement with strain patterns observed in photoelastic test materials and reaction forces measured during these experiments. We use the model to measure strain energy within the test material when different tooth shapes are used. Results show that notched blades deform materials for less strain energy cost than straight blades, giving insights into the energetic relationship between tooth form and prey materials. We identify a hypothetical 'optimal' blade angle that minimizes strain energy costs and test alternative prey materials via virtual experiments. Using experimental data and computational models offers an integrative approach to understand the mechanics of tooth morphology. PMID:22399789

Anderson, P S L; Rayfield, E J

2012-08-01

269

PHYSICS DESIGN GUIDELINES FOR ESTIMATING PLASMA PERFORMANCE IN A BURNING PLASMA EXPERIMENT (FIRE)  

E-print Network

PHYSICS DESIGN GUIDELINES FOR ESTIMATING PLASMA PERFORMANCE IN A BURNING PLASMA EXPERIMENT (FIRE The physics design guidelines for a next step, high- field tokamak, burning plasma experiment (FIRE, Fusion Ignition Research Experiment) have been developed as an update of the ITER Physics Basis (IPB). The plasma

270

Dalton's disputed nitric oxide experiments and the origins of his atomic theory.  

PubMed

In 1808 John Dalton published his first general account of chemical atomic theory, a cornerstone of modern chemistry. The theory originated in his earlier studies of the properties of atmospheric gases. In 1803 Dalton discovered that oxygen combined with either one or two volumes of nitric oxide in closed vessels over water and this pioneering observation of integral multiple proportions provided important experimental evidence for his incipient atomic ideas. Previous attempts to reproduce Dalton's experiments have been unsuccessful and some commentators have concluded the results were fraudulent. We report a successful reconstruction of Dalton's experiments and provide an analysis exonerating him of any scientific misconduct. But we conclude that Dalton, already thinking atomistically, adjusted experimental conditions to obtain the integral combining proportions. PMID:18175369

Usselman, Melvyn C; Leaist, Derek G; Watson, Katherine D

2008-01-11

271

Multi-wavelength holography with a single Spatial Light Modulator for ultracold atom experiments  

E-print Network

We demonstrate a method to create arbitrary intensity distributions of multiple wavelengths of light, which can be useful for ultracold atom experiments, by using regional phase-calculation algorithms to find a single hologram which is illuminated with overlapped laser beams. The regionality of the algorithms is used to program spatially distinct features in the calculated intensity distribution, which then overlap in the Fourier plane due to the dependence of diffraction angle on wavelength. This technique is easily integrated into cold atom experiments, requiring little optical access. We demonstrate the method and two possible experimental scenarios by generating light patterns with 670nm, 780nm and 1064nm laser light which are accurate to the level of a few percent.

Bowman, David; Bruce, Graham D; Cassettari, Donatella

2015-01-01

272

Kinetic theory and atomic physics corrections for determination of ion velocities from charge-exchange spectroscopy  

NASA Astrophysics Data System (ADS)

Charge-exchange spectroscopy is a powerful diagnostic tool for determining ion temperatures, densities and rotational velocities in tokamak plasmas. This technique depends on detailed understanding of the atomic physics processes that affect the measured apparent velocities with respect to the true ion rotational velocities. These atomic effects are mainly due to energy dependence of the charge-exchange cross-sections, and in the case of poloidal velocities, due to gyro-motion of the ion during the finite lifetime of the excited states. Accurate lifetimes are necessary for correct interpretation of measured poloidal velocities, specially for high density plasma regimes on machines such as ITER, where l-mixing effects must be taken into account. In this work, a full nl-resolved atomic collisional radiative model coupled with a full kinetic calculation that includes the effects of electric and magnetic fields on the ion gyro-motion is presented for the first time. The model directly calculates from atomic physics first principles the excited state lifetimes that are necessary to evaluate the gyro-orbit effects. It is shown that even for low density plasmas where l-mixing effects are unimportant and coronal conditions can be assumed, the nl-resolved model is necessary for an accurate description of the gyro-motion effects to determine poloidal velocities. This solution shows good agreement when compared to three QH-mode shots on DIII-D, which contain a wide range of toroidal velocities and high ion temperatures where greater atomic corrections are needed. The velocities obtained from the model are compared to experimental velocities determined from co- and counter-injection of neutral beams on DIII-D.

Muñoz Burgos, J. M.; Burrell, K. H.; Solomon, W. M.; Grierson, B. A.; Loch, S. D.; Ballance, C. P.; Chrystal, C.

2013-09-01

273

Physics results from the National Spherical Torus Experiment  

SciTech Connect

The mission of the National Spherical Torus Experiment (NSTX) is to extend the understanding of toroidal physics to low aspect ratio (R/a {approx} 1.25) in low collisionality regimes. NSTX is designed to operate with up to 6 MW of High Harmonic Fast Wave (HHFW) heating and current drive, 5 MW of Neutral Beam Injection (NBI), and Co-Axial Helicity Injection (CHI) for non-inductive startup. Initial experiments focused on establishing conditions that will allow NSTX to achieve its aims of simultaneous high-{beta}{sub t} and high-bootstrap current fraction, and to develop methods for non-inductive operation, which will be necessary for Spherical Torus power plants. Ohmic discharges with plasma currents up to 1 MA, stored energies up to 55 kJ, {beta}{sub t} {approx} 10%, and a range of shapes and configurations were produced. Density limits in deuterium and helium reached 80% and 120% of the Greenwald limit respectively. Significant electron heating was observed with up to 2.3 MW of HHFW. Up to 270 kA of toroidal current for up to 200 msec was produced noninductively using CHI. Initial NBI experiments were carried out with up to two beam sources (3.2 MW). Plasmas with stored energies of up to 140 kJ and {beta}{sub t}=21% were produced.

Kaye, S.; Bell, M. [and others

2000-11-01

274

Results From the Physics of Colloids Experiment on ISS  

NASA Technical Reports Server (NTRS)

The Physics of Colloids in Space (PCS) experiment was accommodated within International Space Station (ISS) EXpedite the PRocessing of Experiments to Space Station (EXPRESS) Rack 2 and was remotely operated from early June 2001 until February 2002 from NASA Glenn Research Center's Telescience Support Center (TSC) in Cleveland, Ohio, and from the remote site at Harvard University in Cambridge, Massachusetts. PCS was launched on 4/19/2001 on Space Shuttle STS-100. The experiment was activated on 5/31/2001. The entire experimental setup performed remarkably well, and accomplished 2400 hours of science operations on-orbit. The sophisticated instrumentation in PCS is capable of dynamic and static light scattering from 11 to 169 degrees, Bragg scattering over the range from 10 to 60 degrees, dynamic and static light scattering at low angles from 0.3 to 6.0 degrees, and color imaging. The long duration microgravity environment on the ISS facilitated extended studies on the growth and coarsening characteristics of binary crystals. The de-mixing of the colloid-polymer critical-point sample was also studied as it phase-separated into two phases. Further, aging studies on a col-pol gel, gelation rate studies in extremely low concentration fractal gels over several days, and studies on a glass sample, all provided valuable information. Several exciting and unique aspects of these results are discussed here.

Weitz, David; Bailey, Arthur; Manley, Suliana; Prasad, Vikram; Christianson, Rebecca; Sankaran, Subramanian; Doherty, Michael; Jankovsky, Amy; Lorik, Tibor; Shiley, William

2002-01-01

275

Initial Physics Results From the National Spherical Torus Experiment  

SciTech Connect

The mission of the National Spherical Torus Experiment (NSTX) is to extend the understanding of toroidal physics to low aspect ratio (R/a approximately equal to 1.25) in low collisionality regimes. NSTX is designed to operate with up to 6 MW of High Harmonic Fast Wave (HHFW) heating and current drive, 5 MW of Neutral Beam Injection (NBI) and Co-Axial Helicity Injection (CHI) for non-inductive startup. Initial experiments focused on establishing conditions that will allow NSTX to achieve its aims of simultaneous high-bt and high-bootstrap current fraction, and to develop methods for non-inductive operation, which will be necessary for Spherical Torus power plants. Ohmic discharges with plasma currents up to 1 MA and with a range of shapes and configurations were produced. Density limits in deuterium and helium reached 80% and 120% of the Greenwald limit respectively. Significant electron heating was observed with up to 2.3 MW of HHFW. Up to 270 kA of toroidal current for up to 200 msec was produced noninductively using CHI. Initial NBI experiments were carried out with up to two beam sources (3.2 MW). Plasmas with stored energies of up to 140 kJ and bt =21% were produced.

Kaye, S.M.; Bell, M.G.; Bell, R.E.; Bialek, J. [and others

2001-01-03

276

Theory of Spin-Orbit Coupling in Atoms. II. Comparison of Theory with Experiment  

Microsoft Academic Search

Results of calculations of the spin-orbit coupling constant for 2p, 3p, 4p, and 3d shell ions and atoms are presented. The calculations are based on a theory developed in a previous paper. Excellent agreement of this theory with experiment is obtained for the 2p and 3d shell ions, while calculations using the familiar expression for the coupling constant lie 10

M. Blume; R. E. Watson

1963-01-01

277

ATOMIC PHYSICS Note: For the problems in this chapter, useful numerical values of Planck's constant, in SI and atomic units,  

E-print Network

- - - - - - - = Ã? = Ã? = = = Ã? = Ã? = = Ã? = = Ã? = = Ã? = Ã? h Chapter 34, The Bohr Model of the Atom: 56. INTERPRET We are to find the maximum energy conservation of energy and the Bohr model of the atom. We can use these two concepts to find the energy This problem involves the Bohr model of the atom. We are to find the ionization energy of a hydrogen atom

Ringwald, Frederick A.

278

Resolving all-order method convergence problems for atomic physics applications  

SciTech Connect

The development of the relativistic all-order method where all single, double, and partial triple excitations of the Dirac-Hartree-Fock wave function are included to all orders of perturbation theory led to many important results for the study of fundamental symmetries, development of atomic clocks, ultracold atom physics, and others, as well as provided recommended values of many atomic properties critically evaluated for their accuracy for a large number of monovalent systems. This approach requires iterative solutions of the linearized coupled-cluster equations leading to convergence issues in some cases where correlation corrections are particularly large or lead to an oscillating pattern. Moreover, these issues also lead to similar problems in the configuration-interaction (CI)+all-order method for many-particle systems. In this work, we have resolved most of the known convergence problems by applying two different convergence stabilizer methods, namely, reduced linear equation and direct inversion of iterative subspace. Examples are presented for B, Al, Zn{sup +}, and Yb{sup +}. Solving these convergence problems greatly expands the number of atomic species that can be treated with the all-order methods and is anticipated to facilitate many interesting future applications.

Gharibnejad, H.; Derevianko, A. [Department of Physics, University of Nevada, Reno, Nevada 89557 (United States); Eliav, E. [Department of Chemistry, Tel Aviv University, Tel Aviv (Israel); Safronova, M. S. [Department of Physics, University of Delaware, Newark, Delaware 19716 (United States)

2011-05-15

279

Collision physics and collective phenomena with ultra-cold atoms and molecules  

NASA Astrophysics Data System (ADS)

I will describe some of our recent results on collision physics and collective phenomena with ultra-cold atoms and molecules. In particular, we have investigated how radio-frequency radiation can induce new or modify existing Feshbach resonances [1], and how ultra-cold polar molecules, such as KRb, can be formed and themselves collide [2]. We have studied collective phenomena of ultra-cold atoms as well. In particular, we have investigated interference patterns generated by atoms suddenly loaded into an optical lattice [3], the effect of rotation on strongly-interacting fermionic atoms [4], and studied the loss of energy in a three-component spinor-condensate [5].[4pt] [1] A.M. Kaufman, R.P. Anderson, T.M. Hanna, et al., Phys Rev. A 80, 050701(2009)[0pt] [2] S. Kotochigova, E. Tiesinga, P.S. Julienne, New J. Phys 11, 055043 (2009)[0pt] [3] P.R. Johnson, E. Tiesinga, J.V. Porto et al., New J. Phys 11, 093022 (2009)[0pt] [4] M. Iskin, E. Tiesinga, Phys Rev. A 79, 053621 (2009)[0pt] Y. Liu, E. Gomez, S.E. Maxwell, et al., Phys Rev. Lett. 102, 225301 (2009)

Tiesinga, Eite

2010-03-01

280

Use of titanium in the tokamak physics experiment (TPX)  

NASA Astrophysics Data System (ADS)

The titanium alloy Ti?6Al?4V is currently the reference alloy for the vacuum vessel of the tokamak physics experiment (TPX), which will use D?D as fuel. Titanium was selected because it satisfies the requirement of reduced radioactivation of the TPX vacuum vessel. Reduced activation allows the hands-on maintenance of components inside the vacuum vessel during the first two years of operation, with a gradual transition to fully remote maintenance required during the latter phases of TPX's experimental program when the neutron yields are expected to be much higher. It also reduces the eventual waste storage requirements. As part off the R&D program on TPX, two issues on titanium were studied: the impact of the plasma hydrogen absorption on titanium and the welding of thick sections. Based on preliminary analysis, no critical issues were encountered.

Davis, J. W.; Wille, G. W.; Heitzenroeder, P.

1996-10-01

281

Upper Secondary Students' Understanding of the Basic Physical Interactions in Analogous Atomic and Solar Systems  

ERIC Educational Resources Information Center

Comparing the atom to a "tiny solar system" is a common teaching analogy, and the extent to which learners saw the systems as analogous was investigated. English upper secondary students were asked parallel questions about the physical interactions between the components of a simple atomic system and a simple solar system to investigate…

Taber, Keith S.

2013-01-01

282

Self-directed learning: A heretical experiment in teaching physics  

NSDL National Science Digital Library

An account is given of the instruction of university-level introductory physics courses according to an educational framework in which (1) curiosity-driven inquiry is recognized as an essential activity of both science and science teaching; (2) the principal role of the instructor is to provide students the incentive to learn science through their pursuit of personally meaningful questions; (3) the commission of errors is regarded as a natural concomitant to learning and is not penalized; (4) emphasis is placed on laboratory investigations that foster minimally restrictive free exploration rather than prescriptive adherence to formal procedure; (5) research skills are developed through out-of-class projects that involve literature search, experiment, and the modeling of real-world physical phenomena: (6) the precise and articulate use of language is regarded as seminal to communication in science (as it is in the humanities) and is promoted through activities that help develop written and oral language skills; (7) the evaluation of student performance is based on a portfolio of accomplished work rather than on the outcome of formal testing.

Silverman, M. P.

2005-11-23

283

Looking at cell mechanics with atomic force microscopy: experiment and theory.  

PubMed

This review reports on the use of the atomic force microscopy in the investigation of the mechanical properties of cells. It is shown that the technique is able to deliver information about the cell surface properties (e.g., topography), the Young modulus, the viscosity, and the cell the relaxation times. Another aspect that this short review points out is the utilization of the atomic force microscope to investigate basic questions related to materials physics, biology, and medicine. The review is written in a chronological way to offer an overview of phenomenological facts and quantitative results to the reader. The final section discusses in detail the advantages and disadvantages of the Hertz and JKR models. A new implementation of the JKR model derived by Dufresne is presented. PMID:25092263

Benitez, Rafael; Toca-Herrera, José L

2014-11-01

284

Correlations of a single atom and a resonance mode and their manifestation in some physical phenomena  

NASA Astrophysics Data System (ADS)

A kinetic equation governing relaxation of a single two-level atom and a high- Q cavity mode in an entangled thermostat exhibiting quantum correlations is presented. Based on two kinds of collective operators, we demonstrate the possibility of the existence of dual squeezed states in this system. One kind of generator of collective operators corresponds to algebra obtained by polynomial deformation of the angular-momentum algebra, while the other kind corresponds to the Heisenberg-Weyl algebra. Squeezed states of the collective system are defined in terms of commutative relations for operators of the corresponding generator algebras. It is shown that quantum correlations in the system manifest themselves in two physical phenomena. The first one is the known entanglement-swapping protocol and is based on the projection measurement. In the other case, quantum correlations reveal themselves in the coherent scattering dynamics of an atom in the field of a standing light wave.

Gorbachev, V. N.; Trubilko, A. I.

2014-04-01

285

Studies on implementation of pellet tracking in hadron physics experiments  

NASA Astrophysics Data System (ADS)

A system for optical tracking of frozen hydrogen microsphere targets (pellets) has been designed. It is intended for the upcoming hadron physics experiment PANDA at FAIR, Darmstadt, Germany. With such a tracking system one can reconstruct the positions of the individual pellets at the time of a hadronic interaction in the offline event analysis. This gives information on the position of the primary interaction vertex with an accuracy of a few 100 µm, which is very useful e.g. for reconstruction of charged particle tracks and secondary vertices and for background suppression. A study has been done at the WASA detector setup (Forschungszentrum Jülich, Germany) to check the possibility of classification of hadronic events as originating in pellets or in background. The study has been done based on the instantaneous rate a Long Range TDC which was used to determine if a pellet was present in the accelerator beam region. It was clearly shown that it is possible to distinguish the two event classes. Also, an experience was gained with operation of two synchronized systems operating in different time scales, as it will also be the case with the optical pellet tracking.

Pyszniak, A.; Calén, H.; Fransson, K.; Hejny, V.; Johansson, T.; Löfgren, J.; Rudy, Z.; Wolke, M.; Wüstner, P.

2014-11-01

286

Review study and evaluation of possible flight experiments relating to cloud physics experiments in space  

NASA Technical Reports Server (NTRS)

The general objectives of the Zero-Gravity Atmospheric Cloud Physics Laboratory Program are to improve the level of knowledge in atmospheric cloud research by placing at the disposal of the terrestrial-bound atmospheric cloud physicist a laboratory that can be operated in the environment of zero-gravity or near zero-gravity. This laboratory will allow studies to be performed without mechanical, aerodynamic, electrical, or other techniques to support the object under study. The inhouse analysis of the Skylab 3 and 4 experiments in dynamics of oscillations, rotations, collisions and coalescence of water droplets under low gravity-environment is presented.

Hunt, R. J.; Wu, S. T.

1976-01-01

287

Report of the Joint Seminar on Solid State Physics, Atomic and Molecular Physics, and Materials Science in the Energy Region of Tandem Accelerators  

Microsoft Academic Search

The Joint Seminar on Solid State Physics, Atomic and Molecular Physics, and Materials Science in the Energy Region of Tandem Acceleration was held at Tokai Research Establishment of JAERI for two days from January 22 to 23, 1991. About 60 physicists and material scientists participated and 18 papers were presented in this seminar. The topics presented in this seminar included

Yukio Kazumata

1993-01-01

288

Spectroscopy of antiprotonic helium atoms and its contribution to the fundamental physical constants  

PubMed Central

Antiprotonic helium atom, a metastable neutral system consisting of an antiproton, an electron and a helium nucleus, was serendipitously discovered, and has been studied at CERN’s antiproton decelerator facility. Its transition frequencies have recently been measured to nine digits of precision by laser spectroscopy. By comparing these experimental results with three-body QED calculations, the antiproton-to-electron massratio was determined as 1836.152674(5). This result contributed to the CODATA recommended values of the fundamental physical constants. PMID:20075605

Hayano, Ryugo S.

2010-01-01

289

Girls' Experiences in Physical Education: Competition, Evaluation, & Degradation  

ERIC Educational Resources Information Center

School nurses are often asked to participate in the health component of many physical education (PE) programs in schools. With this opportunity comes an ability to invite a model of physical education that enables physical, mental, and relational health. A pilot study was initiated to explore why girls' enrollment in physical education was…

van Daalen, Cheryl

2005-01-01

290

Atomic layer deposition of metal oxide patterns on nonwoven fiber mats using localized physical compression.  

PubMed

Patterning is an essential part of many industrial processes from printing to semiconductor manufacturing. In this work, we demonstrate a new method to pattern and selectively coat nonwoven textiles by atomic layer deposition (ALD) using compressive mask patterning. A physical mask combined with mechanical compression allows lateral definition and fidelity of the ALD coating to be controlled. We produce features of several sizes on different nonwoven fiber materials and demonstrate the ability to limit diffusion effects to within <200 ?m of the pattern edge. Lateral and vertical penetration of reactive growth species into nonwoven mats is investigated by plan-view and cross-sectional imaging. Vertical growth is also analyzed by imaging coating depth into fiber mat stacks. We develop a fully quantitative transport model that describes well the effect of fiber structure and mechanical compression on the extent of coating under the physical mask. This method could be implemented for high-volume patterning for applications including flexible electronics. PMID:24850237

Sweet, William J; Oldham, Christopher J; Parsons, Gregory N

2014-06-25

291

Common Physical Framework Explains Phase Behavior and Dynamics of Atomic, Molecular, and Polymeric Network Formers  

NASA Astrophysics Data System (ADS)

We show that the self-assembly of a diverse collection of building blocks can be understood within a common physical framework. These building blocks, which form periodic honeycomb networks and nonperiodic variants thereof, range in size from atoms to micron-scale polymers and interact through mechanisms as different as hydrogen bonds and covalent forces. A combination of statistical mechanics and quantum mechanics shows that one can capture the physics that governs the assembly of these networks by resolving only the geometry and strength of building-block interactions. The resulting framework reproduces a broad range of phenomena seen experimentally, including periodic and nonperiodic networks in thermal equilibrium, and nonperiodic supercooled and glassy networks away from equilibrium. Our results show how simple "design criteria" control the assembly of a wide variety of networks and suggest that kinetic trapping can be a useful way of making functional assemblies.

Whitelam, Stephen; Tamblyn, Isaac; Haxton, Thomas K.; Wieland, Maria B.; Champness, Neil R.; Garrahan, Juan P.; Beton, Peter H.

2014-01-01

292

The superconducting magnet system for the Tokamak Physics Experiment  

NASA Astrophysics Data System (ADS)

The superconducting magnet system for the Tokamak Physics eXperiment (TPX) will be the first all superconducting magnet system for a Tokamak, where the poloidal field coils, in addition to the toroidal field coils are superconducting. The magnet system is designed to operate in a steady state mode, and to initiate the plasma discharge ohmically. The toroidal field system provides a peak field of 4.0 Tesla on the plasma axis at a plasma major radius of 2.25 m. The peak field on the niobium 3-tin, cable-in-conduit (CIC) conductor is 8.4 Tesla for the 16 toroidal field coils. The toroidal field coils must absorb approximately 5 kW due to nuclear heating, eddy currents, and other sources. The poloidal field system provides a total of 18 volt seconds to initiate the plasma and drive a plasma current up to 2 MA. The poloidal field system consists of 14 individual coils which are arranged symmetrically above and below the horizontal mid plane. Four pairs of coils make up the central solenoid, and three paris of poloidal ring coils complete the system. The poloidal field coils all use a cable-in-conduit conductor, using either niobium 3-tin (NB3Sn) or niobium titanium (NbTi) superconducting strands depending on the operating conditions for that coil. All of the coils are cooled by flowing supercritical helium, with inlet and outlet connections made on each double pancake. The superconducting magnet system has gone through a conceptual design review, and is in preliminary design started by the Lawrence Livermore National Laboratory; Massachusetts Institute of Technology; and the Princeton Plasma Physics Laboratory (LLNL/MIT/PPPL) collaboration. A number of changes have been made in the design since the conceptual design review, and are described in this paper.

Lang, Dwight D.; Bulmer, R. J.; Chaplin, M. R.; Oconner, T. G.; Slack, D. S.; Wong, R. L.; Zbasnik, J. P.; Schultz, J. H.; Diatchenko, N.; Montgomery, D. B.

1994-06-01

293

A Terrestrial, Atom Interferometer, Experiment Searching for Dark Energy Density and Other Dark Contents of the Vacuum  

E-print Network

1 A Terrestrial, Atom Interferometer, Experiment Searching for Dark Energy Density and Other Dark way to investigate the nature of dark energy and at the same time to look for unknown contents, as in Fig. 5, there is an additional force on the atoms caused by dark energy, FDE shift of A is now

Wechsler, Risa H.

294

MISSE 2 PEACE Polymers Experiment Atomic Oxygen Erosion Yield Error Analysis  

NASA Technical Reports Server (NTRS)

Atomic oxygen erosion of polymers in low Earth orbit (LEO) poses a serious threat to spacecraft performance and durability. To address this, 40 different polymer samples and a sample of pyrolytic graphite, collectively called the PEACE (Polymer Erosion and Contamination Experiment) Polymers, were exposed to the LEO space environment on the exterior of the International Space Station (ISS) for nearly 4 years as part of the Materials International Space Station Experiment 1 & 2 (MISSE 1 & 2). The purpose of the PEACE Polymers experiment was to obtain accurate mass loss measurements in space to combine with ground measurements in order to accurately calculate the atomic oxygen erosion yields of a wide variety of polymeric materials exposed to the LEO space environment for a long period of time. Error calculations were performed in order to determine the accuracy of the mass measurements and therefore of the erosion yield values. The standard deviation, or error, of each factor was incorporated into the fractional uncertainty of the erosion yield for each of three different situations, depending on the post-flight weighing procedure. The resulting error calculations showed the erosion yield values to be very accurate, with an average error of 3.30 percent.

McCarthy, Catherine E.; Banks, Bruce A.; deGroh, Kim, K.

2010-01-01

295

The Use of Cylindrical Lenses in Easy Experiments for Physics Education and the Magic Arts  

ERIC Educational Resources Information Center

The purpose of this article is to present the properties of cylindrical lenses and provide some examples of their use in easy school physics experiments. Such experiments could be successfully conducted in the context of science education, in fun experiments that teach physics and in science fair projects, or used to entertain an audience by…

Bednarek, Stanislaw; Krysiak, Jerzy

2011-01-01

296

A preliminary discussion of gravitational physics experiments for the Spacelab era  

NASA Technical Reports Server (NTRS)

An overview of past, present, and proposed future experiments in gravitational physics is given. These experiments are concerned with the measurement of relativistic gravity effects to test theories of gravitation. Certain experiments which could be performed on shuttle and Spacelab missions and the potential of Spacelab for gravitation physics research are discussed.

Decher, R.; Winkler, C. G.

1976-01-01

297

The use of cylindrical lenses in easy experiments for physics education and the magic arts  

Microsoft Academic Search

The purpose of this article is to present the properties of cylindrical lenses and provide some examples of their use in easy school physics experiments. Such experiments could be successfully conducted in the context of science education, in fun experiments that teach physics and in science fair projects, or used to entertain an audience by staging tricks, effects or illusions

Stanislaw Bednarek; Jerzy Krysiak

2011-01-01

298

Mini-Column Ion-Exchange Separation and Atomic Absorption Quantitation of Nickel, Cobalt, and Iron: An Undergraduate Quantitative Analysis Experiment.  

ERIC Educational Resources Information Center

Presents an undergraduate quantitative analysis experiment, describing an atomic absorption quantitation scheme that is fast, sensitive and comparatively simple relative to other titration experiments. (CS)

Anderson, James L.; And Others

1980-01-01

299

GEC Foundation Talk: Electron Collisions with Atoms, Ions, and Molecules: Experiment, Theory, and Applications  

NASA Astrophysics Data System (ADS)

In recent years, much progress has been made in the study of electron collisions with various atomic and molecular species. This includes high-resolution benchmark experiments that cover large angular and energy ranges, highly sophisticated calculations that can provide accurate and extensive data sets, and the use of these data sets in realistic models of plasma discharges. The basic principles of frequently used experimental setups and computational methods will be reviewed, and the current state of the art will be illustrated with numerous examples.

Bartschat, Klaus

2012-10-01

300

The Spheromak Turbulence Experiment: The Next Phase in Spheromak Physics  

NASA Astrophysics Data System (ADS)

The spheromak turbulence experiment (STPX) is a collaboration between FAMU, WVU, Auburn University, and Woodruff Scientific, Inc. The fundamental purpose of STPX is to advance Spheromak physics toward producing a burning plasma and new insights on astrophysical systems with magnetic reconnection. FAMU will employ microwave pulses to manipulate the stable state. In addition, closely coupled NIMROD modeling and experimentation will take place using the FAMU computational cluster. Auburn University is providing a pair of movable probe arrays consisting of a triple probe and a series of four saturation current/floating potential probes for making instantaneous measurements of plasma parameters. West Virginia University is providing an array of (N), X-MHz, B-dot coils for making measurements of magnetic fluctuations. West Virginia University is also providing an array of 25, 2 MHz bandwidth, B-dot coils and differential amplifiers for making high time-resolution measurements of magnetic fluctuations at the edge of the plasma. Woodruff Scientific designed and constructed the STPX vessel.

Mezonlin, Ephrem; Williams, Kyron; Weatherford, C. A.; Johnson, J. A., III; Alexander, A. B.; Scime, Earl; Keesee, A.; Lusk, G.; Reynolds, E.; Vandervort, R.; Arnold, N. I.; Gilmore, K.; Thomas, E., Jr.; Woodruff, Simon

2011-11-01

301

Testing the Bell Inequality at Experiments of High Energy Physics  

E-print Network

Besides using the laser beam, it is very tempting to directly testify the Bell inequality at high energy experiments where the spin correlation is exactly what the original Bell inequality investigates. In this work, we follow the proposal raised in literature and use the successive decays $J/\\psi\\to\\gamma\\eta_c\\to \\Lambda\\bar\\Lambda\\to p\\pi^-\\bar p\\pi^+$ to testify the Bell inequality. Our goal is twofold, namely, we first make a Monte-Carlo simulation of the processes based on the quantum field theory (QFT). Since the underlying theory is QFT, it implies that we pre-admit the validity of quantum picture. Even though the QFT is true, we need to find how big the database should be, so that we can clearly show deviations of the correlation from the Bell inequality determined by the local hidden variable theory. There have been some critiques on the proposed method, so in the second part, we suggest some improvements which may help to remedy the ambiguities indicated by the critiques. It may be realized at an updated facility of high energy physics, such as BES III.

Xi-Qing Hao; Hong-Wei Ke; Yi-Bing Ding; Peng-Nian Shen; Xue-Qian Li

2009-04-07

302

Experiences developing ALEGRA: A C++ coupled physics framework  

SciTech Connect

ALEGRA is a coupled physics framework originally written to simulate inertial confinement fusion (ICF) experiments being conducted at the PBFA-II facility at Sandia National Laboratories. It has since grown into a large software development project supporting a number of computational programs at Sandia. As the project has grown, so has the development team, from the original two authors to a group of over fifteen programmers crossing several departments. In addition, ALEGRA now runs on a wide variety of platforms, from large PCs to the ASCI Teraflops massively parallel supercomputer. The authors discuss the reasons for ALEGRA`s success, which include the intelligent use of object-oriented techniques and the choice of C++ as the programming language. They argue that the intelligent use of development tools, such as build tools (e.g. make), compiler, debugging environment (e.g. dbx), version control system (e.g. cvs), and bug management software (e.g. ClearDDTS), is nearly as important as the choice of language and paradigm.

Budge, K.G.; Peery, J.S.

1998-11-01

303

FPGA-based Cherenkov Ring Recognition in Nuclear and Particle Physics Experiments  

E-print Network

FPGA-based Cherenkov Ring Recognition in Nuclear and Particle Physics Experiments Ming Liu adopted to identify particles flying through the detector systems in nuclear and particle physics for particle recognition. 1 Introduction Nuclear and particle physics is a branch of physics that studies

Jantsch, Axel

304

Electrochromic WO[subscript 3] Films: Nanotechnology Experiments in Instrumental Analysis and Physical Chemistry Laboratories  

ERIC Educational Resources Information Center

This experiment teaches students the methodology of investigating novel properties of materials using new instrumental techniques: atomic force microscopy (AFM), electrochemical quartz crystal nanobalance (EQCN), voltammetric techniques (linear potential scan and chronoamperometry), and light reflectance measurements. The unique capabilities of…

Hepel, Maria

2008-01-01

305

Physics of forced magnetic reconnection in coaxial helicity injection experiments in National Spherical Torus Experiment  

SciTech Connect

We numerically examine the physics of fast flux closure in transient coaxial helicity injection (CHI) experiments in National Spherical Torus Experiment (NSTX). By performing resistive Magnetohydrodynamics (MHD) simulations with poloidal injector coil currents held constant in time, we find that closed flux surfaces are formed through forced magnetic reconnection. Through a local Sweet-Parker type reconnection with an elongated current sheet in the injector region, closed flux surfaces expand in the NSTX global domain. Simulations demonstrate outflows approaching poloidally Alfvénic flows and reconnection times consistent with the Sweet-Parker model. Critical requirements for magnetic reconnection and flux closure are studied in detail. These primary effects, which are magnetic diffusivity, injector flux, injector flux footprint width, and rate of injector voltage reduction, are simulated for transient CHI experiments. The relevant time scales for effective reconnection are ?{sub V}

Ebrahimi, F.; Bhattacharjee, A. [Department of Astrophysical Sciences, and Princeton Plasma Physics Laboratory, Princeton University, New Jersey 08544 (United States)] [Department of Astrophysical Sciences, and Princeton Plasma Physics Laboratory, Princeton University, New Jersey 08544 (United States); Raman, R. [University of Washington, Seattle, Washington 98195 (United States)] [University of Washington, Seattle, Washington 98195 (United States); Hooper, E. B. [Lawrence Livermore National Laboratory, Livermore, California 94526 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94526 (United States); Sovinec, C. R. [University of Wisconsin, Madison, Wisconsin 53706 (United States)] [University of Wisconsin, Madison, Wisconsin 53706 (United States)

2014-05-15

306

H I ZEEMAN EXPERIMENTS OF SHOCKED ATOMIC GAS IN TWO SUPERNOVA REMNANTS INTERACTING WITH MOLECULAR CLOUDS  

SciTech Connect

We have carried out observations of Zeeman splitting of the H I 21 cm emission line from shocked atomic gas in the supernova remnants (SNRs) IC 443 and W51C using the Arecibo telescope. The observed shocked atomic gas is expanding at {approx}100 km s{sup -1} and this is the first Zeeman experiment of such fast-moving, shocked atomic gas. The emission lines, however, are very broad and the systematic error due to baseline curvature hampers an accurate measurement of field strengths. We derive an upper limit of 100-150 {mu}G on the strength of the line-of-sight field component. These two SNRs are interacting with molecular clouds, but the derived upper limits are considerably smaller than the field strengths expected from a strongly shocked dense cloud. We discuss the implications and conclude that either the magnetic field within the telescope beam is mostly randomly oriented or the high-velocity H I emission is from a shocked interclump medium of relatively low density.

Koo, Bon-Chul [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Heiles, Carl [Astronomy Department, University of California, Berkeley, CA 94720-3411 (United States); Stanimirovic, Snezana [Department of Astronomy, University of Wisconsin-Madison, Madison, WI 53706 (United States); Troland, Tom, E-mail: koo@astrohi.snu.ac.k [Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States)

2010-07-15

307

Two cultures? Experiences at the physics-biology interface  

NASA Astrophysics Data System (ADS)

‘I didn’t really think of this as moving into biology, but rather as exploring another venue in which to do physics.’ John Hopfield provides a personal perspective on working on the border between physical and biological sciences.

Hopfield, John J.

2014-10-01

308

The polarized atomic-beam target for the EDDA experiment and the time-reversal invariance test at COSY  

NASA Astrophysics Data System (ADS)

For the the EDDA experiment, which was set up to measure the p¯-p¯ excitation function during the acceleration ramp of the cooler synchrotron COSY at Jülich, a polarized atomic-beam target was designed regarding the restrictions imposed by the geometry of the EDDA detector. Later, when the time-reversal invariance experiment is to be performed, the EDDA detector will serve as efficient internal polarimeter and the source has to deliver tensor polarized deuterons. The modular design of this polarized atomic-beam target that allows to meet these conditions will be discussed in comparison to other existing polarized atomic-beam targets.

Eversheim, P. D.; Altmeier, M.; Felden, O.

1997-02-01

309

Solid Hydrogen Experiments for Atomic Propellants: Particle Formation, Imaging, Observations, and Analyses  

NASA Technical Reports Server (NTRS)

This report presents particle formation observations and detailed analyses of the images from experiments that were conducted on the formation of solid hydrogen particles in liquid helium. Hydrogen was frozen into particles in liquid helium, and observed with a video camera. The solid hydrogen particle sizes and the total mass of hydrogen particles were estimated. These newly analyzed data are from the test series held on February 28, 2001. Particle sizes from previous testing in 1999 and the testing in 2001 were similar. Though the 2001 testing created similar particles sizes, many new particle formation phenomena were observed: microparticles and delayed particle formation. These experiment image analyses are some of the first steps toward visually characterizing these particles, and they allow designers to understand what issues must be addressed in atomic propellant feed system designs for future aerospace vehicles.

Palaszewski, Bryan

2005-01-01

310

Solid Hydrogen Experiments for Atomic Propellants: Particle Formation Energy and Imaging Analyses  

NASA Technical Reports Server (NTRS)

This paper presents particle formation energy balances and detailed analyses of the images from experiments that were conducted on the formation of solid hydrogen particles in liquid helium during the Phase II testing in 2001. Solid particles of hydrogen were frozen in liquid helium and observed with a video camera. The solid hydrogen particle sizes and the total mass of hydrogen particles were estimated. The particle formation efficiency is also estimated. Particle sizes from the Phase I testing in 1999 and the Phase II testing in 2001 were similar. Though the 2001 testing created similar particles sizes, many new particle formation phenomena were observed. These experiment image analyses are one of the first steps toward visually characterizing these particles and it allows designers to understand what issues must be addressed in atomic propellant feed system designs for future aerospace vehicles.

Palaszewski, Bryan

2002-01-01

311

Fusion Ignition Research Experiment (FIRE) Princeton Plasma Physics Laboratory  

E-print Network

was constrained with the goal to achieve the most important physics goals at a construction cost of plasma issues: Burning Plasma Physics - The achievement and understanding of self-heated plasmas Toroidal Physics - The achievement and understanding of sustained self- heated plasmas with characteristics

312

Early Atomic Models From Mechanical to Quantum (1904-1913) The European Physical Journal H (2012) DOI: 10.1140/epjh/e2012-30009-7  

E-print Network

Early Atomic Models ­ From Mechanical to Quantum (1904-1913) The European Physical Journal H (2012 coherent tale of the path from mechanical atoms to the quantum can of Thomson's mechanical atomic models, from his ethereal vortex atoms in the early

Colorado at Boulder, University of

313

Effect of Calcium and Magnesium on Phosphatidylserine Membranes: Experiments and All-Atomic Simulations  

PubMed Central

It is known that phosphatidylserine (PS?) lipids have a very similar affinity for Ca2+ and Mg2+ cations, as revealed by electrokinetic and stability experiments. However, despite this similar affinity, experimental evidence shows that the presence of Ca2+ or Mg2+ induces very different aggregation behavior for PS? liposomes as characterized by their fractal dimensions. Also, turbidity measurements confirm substantial differences in aggregation behavior depending on the presence of Ca2+ or Mg2+ cations. These puzzling results suggest that although these two cations have a similar affinity for PS? lipids, they induce substantial structural differences in lipid bilayers containing each of these cations. In other words, these cations have strong ion-specific effects on the structure of PS? membranes. This interpretation is supported by all-atomic molecular-dynamics simulations showing that Ca2+ and Mg2+ cations have different binding sites and induce different membrane hydration. We show that although both ions are incorporated deep into the hydrophilic region of the membrane, they have different positions and configurations at the membrane. Absorbed Ca2+ cations present a peak at a distance ?2 nm from the center of the lipid bilayer, and their most probable binding configuration involves two oxygen atoms from each of the charged moieties of the PS molecule (phosphate and carboxyl groups). In contrast, the distribution of absorbed Mg2+ cations has two different peaks, located a few angstroms before and after the Ca2+ peak. The most probable configurations (corresponding to these two peaks) involve binding to two oxygen atoms from carboxyl groups (the most superficial binding peak) or two oxygen atoms from phosphate groups (the most internal peak). Moreover, simulations also show differences in the hydration structure of the membrane: we obtained a hydration of 7.5 and 9 water molecules per lipid in simulations with Ca2+ and Mg2+, respectively. PMID:22824273

Martín-Molina, Alberto; Rodríguez-Beas, César; Faraudo, Jordi

2012-01-01

314

First experience with the ATOMS® implant, a new treatment option for male urinary incontinence  

PubMed Central

Introduction Urinary incontinence (UI) is defined as any complaint of involuntary urine leakage. A description is provided of our experience with the ATOMS® (Adjustable Transobturator Male System. Agency for Medical Innovations. A.M.I.) adjustable implant in patients with mild to moderate UI. Material and methods A retrospective study was made of the data referring to 13 patients treated with this adjustable system. Demographic and personal data were collected along with information on the etiology, severity, characteristics, duration of UI, complementary tests, surgery times, complications and results obtained. Results The full continence (no use of pad) recovery rate at the close of the study was 12/13 (92.3%). Three cases required a single filling during the mean 16 months of follow–up (range 4–32; median 14 months). A complication in the form of perineal hematoma was resolved with conservative treatment and a case of urinary retention was resolved by placing a bladder catheter for the duration of one week. Three patients experienced perineal–scrotal dysesthesias that disappeared spontaneously in the first three months. Conclusions The described adjustable continence system has been found to be very effective in males with mild to moderate UI. In our experience, the ATOMS® implant offers excellent results over the middle term with a very low rate of complications that were easily resolved in all cases. PMID:25667760

Cansino, Jose Ramón; Portilla, María Alejandra; Rodriguez, Simón Claudio; Hidalgo, Luis; De la Peña, Javier

2014-01-01

315

Microgravity experiments on ISS in order to examine a new atomization theory discovered through normalgravity and microgravity environments  

NASA Astrophysics Data System (ADS)

In order to elucidate turbulent atomization processes, many studies by the use of a liquid jet issuing from a circular nozzle have been conducted for a long time. Although Rayleigh's instability has been regarded as the only determinant for the breakup of the liquid jet, the source of the disturbances has been unclear and thus the physical explanation of experimental results was impossible. From our experimental and numerical approaches under normalgravity and microgravity environments, it was found that the breakup by the short-wave mode occurs around the tip of the liquid jet without any disturbances. The long-wave mode is caused by the existence of a nozzle exit through a self-closed breakup cycle sustained inherently by the capillary waves emanated from the tip of the liquid jet after every breakup. Our further experiments revealed the existence of the relaxation region which gives a reasonable explanation of the extremely large breakup length. In addition, the two-valueness of the breakup length was found through a lot of experimental results. Establishment of a new breakup theory enable to explain all of experimental results requires long-period microgravity environments and the currently-projected experiments on ISS are introduced in the present paper.

Osaka, J.; Suzuki, S.; Suzuki, Y.; Umemura, A.

2011-12-01

316

High heat flux testing of CFC composites for the tokamak physics experiment  

NASA Astrophysics Data System (ADS)

High heat flux (HHF) testing of carbon fiber reinforced carbon composites (CFC's) was conducted under the General Atomics program to develop plasma-facing components (PFC's) for Princeton Plasma Physics Laboratory's tokamak physics experiment (TPX). As part of the process of selecting TPX CFC materials, a series of HHF tests were conducted with the 30 kW electron beam test system (EBTS) facility at Sandia National Laboratories, and with the plasma disruption simulator I (PLADIS-I) facility at the University of New Mexico. The purpose of the tests was to make assessments of the thermal performance and erosion behavior of CFC materials. Tests were conducted with 42 different CFC materials. In general, the CFC materials withstood the rapid thermal pulse environments without fracturing, delaminating, or degrading in a non-uniform manner; significant differences in thermal performance, erosion behavior, vapor evolution, etc. were observed and preliminary findings are presented below. The CFC's exposed to the hydrogen plasma pulses in PLADIS-I exhibited greater erosion rates than the CFC materials exposed to the electron-beam pulses in EBTS. The results obtained support the continued consideration of a variety of CFC composites for TPX PFC components.

Valentine, P. G.; Nygren, R. E.; Burns, R. W.; Rocket, P. D.; Colleraine, A. P.; Lederich, R. J.; Bradley, J. T.

1996-10-01

317

The physics of non-Newtonian liquid slurry atomization. Part 2: Twin-fluid atomization of non-Newtonian liquids -- First quarterly technical report, 1 January--31 March 1994  

SciTech Connect

The changes in the physical processes of atomization as a result of adding a high molecular weight polymer in low concentrations to liquid have been studied. Both Newtonian and non-Newtonian liquids were investigated with particular emphasis on the non-Newtonian rheological characteristics. It was found that viscoelastic liquids are much more difficult to atomize than viscoinelastic liquids. Viscoinelastic liquids showed a breakup behavior similar to that of water sprays. Viscoelastic materials showed remarkably different breakup patterns. The ligaments were seen to undergo a very large stretching motion before they breakup, resulting in long threads of liquid attached to droplets. The normal stresses developed in viscoelastic materials are much higher than their associated shear stresses. Consequently, the development of the large normal stresses appears to be the most important rheological mechanism that inhibits breakup. The non-Newtonian liquids selected for the experiment were aqueous solutions of Xanthan gum and Polyacrylamide E10.

Mansour, A.; Chigier, N.

1994-06-01

318

Plasma diagnostics for the sustained spheromak physics experiment  

SciTech Connect

In this article we present an overview of the plasma diagnostics operating or planned for the sustained spheromak physics experiment device now operating at Lawrence Livermore National Laboratory. A set of 46 wall-mounted magnetic probes provide the essential data necessary for magnetic reconstruction of the Taylor relaxed state. Rogowski coils measure currents induced in the flux conserver. A CO{sub 2} laser interferometer is used to measure electron line density. Spectroscopic measurements include an absolutely-calibrated spectrometer recording extended domain spectrometer for obtaining time-integrated visible ultraviolet spectra and two time-resolved vacuum monochrometers for studying the time evolution of two separate emission lines. Another time-integrated spectrometer records spectra in the visible range. Filtered silicon photodiode bolometers provide total power measurements, and a 16 channel photodiode spatial array gives radial emission profiles. Two-dimensional imaging of the plasma and helicity injector is provided by gated television cameras and associated image-processing software. An array of fiber-coupled photodetectors with H alpha filters view across the midplane and in the injector region to measure neutral hydrogen concentrations. Several novel diagnostics are being fielded including a transient internal probe (TIP) and an ultrashort-pulse reflectometer (USPR) microwave reflectometer. The TIP probe fires a very high velocity optical bullet through the plasma and will provide fairly nonpertabative internal magnetic field and current measurements to compare with an equilibrium code model fitted to wall-mounted probes. The USPR is being designed to study edge density and turbulent fluctuations. A multipoint Thomson scattering system is currently being installed to give radial temperature and density profiles.

McLean, H. S.; Ahmed, A.; Buchenauer, D.; Den Hartog, D.; Domier, C. W.; Hill, D. N.; Holcomb, C.; Hooper, E. B.; Morse, E. C.; Nagata, M. (and others) [and others

2001-01-01

319

GRACE-enabled Space Geodetic Experiments for Fundamental Physics  

NASA Astrophysics Data System (ADS)

Space geodesy provided for decades the most precise measurement of positions and velocities of earthbound tracking stations, as well as the most precise orbits of earth-orbiting artificial satellites. While the latter applies to any satellite carrying the appropriate reflectors, the use of these orbits for precise geodetic products requires the use of specially designed target satellites in high altitude orbits, such as the two LAGEOS satellites. To achieve such high quality, the motion of these satellites must be described with equally accurate models, such as those made available recently, thanks to missions like CHAMP and GRACE. This led to the synergistic application of such precise products to devise tests of fundamental physics theories. Nearly twenty years after conceiving and proposing a test concept for a General Relativity (GR) test of the gravitomagnetic effect of the rotating Earth, our recent experiment resulted in a positive and convincing measurement of the Lense-Thirring effect. Using state-of-the-art Earth gravitational field models based on data from the CHAMP and GRACE missions, we obtained an accurate measurement of the Lense Thirring effect predicted by GR, analyzing eleven years of LAGEOS and LAGEOS 2 Satellite Laser Ranging (SLR) data. The new result, in agreement that based on Earth models JGM-3 and EGM96, is far more accurate and more robust. The present analysis uses only the nodal rates of the two satellites, making NO use of the perigee rate, thus eliminating the dependence on this unreliable element. Using the EIGEN-GRACE02S model, we obtained our optimal result: ? = 0.99 (vs. 1.0 in GR), with a total error between ±0.05 and ±0.1, i.e., between 5% and 10 % of the GR prediction. Further improvement of the gravitational models will lead to even more accurate tests. We discuss the LAGEOS results and some of the crucial areas to be considered in designing the future LARES mission dedicated to this test.

Ciufolini, I.; Pavlis, E. C.

2006-12-01

320

ICF Ablator Physics Experiments on Saturn and Nova  

NASA Astrophysics Data System (ADS)

In indirect drive ICF, the driver energy is absorbed in a high-Z enclosure (or "hohlraum") that surrounds a spherical shell (or "capsule") containing DT fuel. The hohlraum walls are heated by the driver and emit x-rays, which are absorbed by the capsule material (the "ablator") and drive the implosion. We have used the Saturn z-pinch at SNL and the Nova laser at LLNL to explore the behavior of ablator material in x-ray radiation environments comparable in magnitude, spectrum and duration to those that will be experienced in National Ignition Facility (NIF) hohlraums. The large x-ray outputs available from pulsed-power driven z-pinches have enabled us to drive hohlraums of full NIF ignition scale size at radiation temperatures and timescales comparable to those required for the low power "foot" pulse of an ignition capsule. The high intensity of the Nova laser has allowed us to study capsule ablator physics in smaller scale hohlraums at radiation temperatures and timescales relevant to the peak power pulse for an ignition capsule. Taken together, these experiments have allowed us test our radiation-hydrodynamics computer code predictions of ablator opacity, radiation flow, and equation of state over almost the complete range of radiation environments to be encountered in a NIF hohlraum. * in collaboration with J. Porter, G. Chandler, D. Fehl, D. Jobe, R. Leeper, K. Matzen, J. McGurn, D. Noack, L. Ruggles, P. Sawyer, J. Torres, M. Vargas, D. Zagar (SNL), and H. Kornblum, T. Orzechowski, L. Suter, R. Thiessen, R. Wallace (LLNL), and the Saturn and Nova operations and diagnostic crews at SNL and LLNL. +This work was supported by the U. S. Department of Energy under Contract No. DE-AC04-94AL85000.

Olson, Rick

1996-11-01

321

The Kinetics and Thermodynamics of the Phenol from Cumene Process: A Physical Chemistry Experiment.  

ERIC Educational Resources Information Center

Presents a physical chemistry experiment demonstrating the differences between thermodynamics and kinetics. The experiment used the formation of phenol and acetone from cumene hydroperoxide, also providing an example of an industrially significant process. (CS)

Chen, Edward C. M.; Sjoberg, Stephen L.

1980-01-01

322

Phase separation during the Experiment on Physics of Colloids in Space  

NASA Technical Reports Server (NTRS)

Still photographs taken over 16 hours on Nov. 13, 2001, on the International Space Station have been condensed into a few seconds to show the de-mixing -- or phase separation -- process studied by the Experiment on Physics of Colloids in Space. Commanded from the ground, dozens of similar tests have been conducted since the experiment arrived on ISS in 2000. The sample is a mix of polymethylmethacrylate (PMMA or acrylic) colloids, polystyrene polymers and solvents. The circular area is 2 cm (0.8 in.) in diameter. The phase separation process occurs spontaneously after the sample is mechanically mixed. The evolving lighter regions are rich in colloid and have the structure of a liquid. The dark regions are poor in colloids and have the structure of a gas. This behavior carnot be observed on Earth because gravity causes the particles to fall out of solution faster than the phase separation can occur. While similar to a gas-liquid phase transition, the growth rate observed in this test is different from any atomic gas-liquid or liquid-liquid phase transition ever measured experimentally. Ultimately, the sample separates into colloid-poor and colloid-rich areas, just as oil and vinegar separate. The fundamental science of de-mixing in this colloid-polymer sample is the same found in the annealing of metal alloys and plastic polymer blends. Improving the understanding of this process may lead to improving processing of these materials on Earth.

2003-01-01

323

Movie of phase separation during physics of colloids in space experiment  

NASA Technical Reports Server (NTRS)

Still photographs taken over 16 hours on Nov. 13, 2001, on the International Space Station have been condensed into a few seconds to show the de-mixing -- or phase separation -- process studied by the Experiment on Physics of Colloids in Space. Commanded from the ground, dozens of similar tests have been conducted since the experiment arrived on ISS in 2000. The sample is a mix of polymethylmethacrylate (PMMA or acrylic) colloids, polystyrene polymers and solvents. The circular area in the video is 2 cm (0.8 in.) in diameter. The phase separation process occurs spontaneously after the sample is mechanically mixed. The evolving lighter regions are rich in colloid and have the structure of a liquid. The dark regions are poor in colloids and have the structure of a gas. This behavior carnot be observed on Earth because gravity causes the particles to fall out of solution faster than the phase separation can occur. While similar to a gas-liquid phase transition, the growth rate observed in this test is different from any atomic gas-liquid or liquid-liquid phase transition ever measured experimentally. Ultimately, the sample separates into colloid-poor and colloid-rich areas, just as oil and vinegar separate. The fundamental science of de-mixing in this colloid-polymer sample is the same found in the annealing of metal alloys and plastic polymer blends. Improving the understanding of this process may lead to improving processing of these materials on Earth.

2002-01-01

324

Accelerator Preparations for Muon Physics Experiments at Fermilab  

SciTech Connect

The use of existing Fermilab facilities to provide beams for two muon experiments - the Muon to Electron Conversion Experiment (Mu2e) and the New g-2 Experiment - is under consideration. Plans are being pursued to perform these experiments following the completion of the Tevatron Collider Run II, utilizing the beam lines and storage rings used today for antiproton accumulation without considerable reconfiguration. Operating scenarios being investigated and anticipated accelerator improvements or reconfigurations will be presented.

Syphers, M.J.; /Fermilab

2009-10-01

325

The AMS Measurements and Its Applications in Nuclear Physics at China Institute of Atomic Energy (CIAE)  

SciTech Connect

Accelerator Mass Spectrometry (AMS), initiated in late 1970s at McMaster university based on the accelerator and detector technique, has long been applied in the studies on archaeology, geology, and cosmology, as a powerful tool for isotope dating. The advantages of AMS in the analysis of rare nuclides by direct counting of the atoms, small sample size and relatively free from the interferences of molecular ions have been well documented. This paper emphasizes that AMS can not only be used for archaeology, geology, environment, biology and so on, but also served as a unique tool for nuclear physics research. In this paper, the determination of the half-lives of {sup 79}Se, the measurements of the cross-sections of {sup 93}Nb(n,2n){sup 92g}Nb and {sup 238}U(n,3n){sup 236}U reactions, the detection and determination of ultratrace impurities in neutrino detector materials, and the measurement of the fission product nuclide {sup 126}Sn, are to be introduced, as some of examples of AMS applications in nuclear research conducted in AMS lab of China Institute of Atomic Energy. Searching for superheavy nuclides by using AMS is being planned.

Jiang Shan; Shen Hongtao; He Ming; Dong Kejun; He Guozhu; Wang Xianggao; Yuan Jian; Wang Wei; Wu Shaoyong [China Institute of Atomic Energy, P.O.Box 275-80, Beijing 102413 (China); Ruan Xiangdong; Wu Weimin [College of Physics, Guangxi University, Nanning 530004 (China)

2010-05-12

326

Physics Demonstration Experiments at William Jewell College. Revised Edition.  

ERIC Educational Resources Information Center

Presented are descriptions (with photographs) of demonstration equipment purchased, assembled, developed, and used at William Jewell College (Missouri) during the past 25 years. The descriptions are organized into the following topic areas: (1) mechanics; (2) heat; (3) waves, sound, and acoustics; (4) electricity; (5) optics; and (6) atomic and…

Hilton, Wallace A.

327

Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics  

Microsoft Academic Search

A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based

G. Aad; E. Abat; B. Abbott; J. Abdallah; A. A. Abdelalim; A. Abdesselam; O. Abdinov; B. Abi; M. Abolins; H. Abramowicz; B. S. Acharya; D. L. Adams; T. N. Addy; C. Adorisio; P. Adragna; T. Adye; J. A. Aguilar-Saavedra; M. Aharrouche; S. P. Ahlen; F. Ahles; A. Ahmad; H. Ahmed; G. Aielli; T. Akdogan; T. P. A. Akesson; G. Akimoto; M. S. Alam; M. A. Alam; J. Albert; S. Albrand; M. Aleksa; I. N. Aleksandrov; F. Alessandria; C. Alexa; G. Alexander; G. Alexandre; T. Alexopoulos; M. Alhroob; G. Alimonti; J. Alison; M. Aliyev; P. P. Allport; S. E. Allwood-Spiers; A. Aloisio; R. Alon; A. Alonso; J. Alonso; M. G. Alviggi; K. Amako; P. Amaral; C. Amelung; V. V. Ammosov; A. Amorim; G. Amoros; N. Amram; C. Anastopoulos; C. F. Anders; K. J. Anderson; A. Andreazza; V. Andrei; M-L. Andrieux; X. S. Anduaga; F. Anghinolfi; A. Antonaki; M. Antonelli; S. Antonelli; B. Antunovic; F. A. Anulli; G. Arabidze; I. Aracena; Y. Arai; A. T. H. Arce; J. P. Archambault; S. Arfaoui; J-F. Arguin; T. Argyropoulos; E. Arik; M. Arik; A. J. Armbruster; O. Arnaez; C. Arnault; A. Artamonov; D. Arutinov; M. Asai; S. Asai; S. Ask; B. Asman; D. Asner; L. Asquith; K. Assamagan; A. Astbury; A. Astvatsatourov; T. Atkinson; G. Atoian; B. Auerbach; E. Auge; K. Augsten; M. A. Aurousseau; N. Austin; G. Avolio; R. Avramidou; A. Axen; C. Ay; G. Azuelos; Y. Azuma; M. A. Baak; G. Baccaglioni; C. Bacci; H. Bachacou; K. Bachas; M. Backes; E. Badescu; P. Bagnaia; Y. Bai; D. C. Bailey; J. T. Baines; O. K. Baker; F. Baltasar Dos Santos Pedrosa; E. Banas; S. Banerjee; D. Banfi; A. Bangert; V. Bansal; S. P. Baranov; A. Barashkou; T. B. Barber; E. L. Barberio; D. Barberis; M. B. Barbero; D. Y. Bardin; T. Barillari; M. Barisonzi; T. Barklow; N. B. Barlow; N. B. Barlow; R. M. Barnett; S. Baron; A. Baroncelli; A. Baroncelli; F. Barreiro; J. Barreiro Guimaraes da Costa; P. Barrillon; R. Bartoldus; D. Bartsch; J. Bastos; R. L. Bates; J. R. Batley; A. Battaglia; M. Battistin; F. Bauer; M. Bazalova; B. Beare; P. H. Beauchemin; R. B. Beccherle; N. Becerici; P. Bechtle; G. A. Beck; H. P. Beck; M. Beckingham; K. H. Becks; I. Bedajanek; A. J. Beddall; P. Bednar; V. A. Bednyakov; C. Bee; S. Behar Harpaz; P. K. Behera; M. Beimforde; C. Belanger-Champagne; P. J. Bell; W. H. Bell; G. Bella; L. Bellagamba; F. Bellina; M. Bellomo; A. Belloni; K. Belotskiy; O. Beltramello; S. Ben Ami; O. Beltramello; D. Benchekroun; M. Bendel; B. H. Benedict; N. Benekos; Y. Benhammou; G. P. Benincasa; D. P. Benjamin; M. Benoit; J. R. Bensinger; K. Benslama; S. Bentvelsen; M. Beretta; D. Berge; E. Bergeaas Kuutmann; N. Berger; F. Berghaus; E. Berglund; J. Beringer; K. Bernardet; P. Bernat; R. Bernhard; C. Bernius; T. Berry; A. Bertin; N. Besson; S. Bethke; R. M. Bianchi; M. Bianco; O. Biebel; J. Biesiada; M. Biglietti; H. Bilokon; S. Binet; A. Bingul; C. Bini; C. Biscarat; M. Bischofberger; U. Bitenc; K. M. Black; R. E. Blair; G. Blanchot; C. Blocker; J. Blocki; A. Blondel; W. Blum; U. Blumenschein; C. Boaretto; G. J. Bobbink; A. Bocci; B. Bodine; J. Boek; N. Boelaert; S. Boeser; J. A. Bogaerts; A. Bogouch; C. Bohm; J. Bohm; V. Boisvert; T. Bold; V. Boldea; V. G. Bondarenko; M. Bondioli; M. Boonekamp; C. N. Booth; P. S. L. Booth; J. R. A. Booth; A. Borisov; G. Borissov; I. Borjanovic; S. Borroni; K. Bos; D. Boscherini; M. Bosman; M. Bosteels; H. Boterenbrood; J. Bouchami; J. Boudreau; E. V. Bouhova-Thacker; C. Boulahouache; C. Bourdarios; J. Boyd; I. R. Boyko; A. Braem; P. Branchini; G. W. Brandenburg; A. Brandt; O. Brandt; U. Bratzler; J. E. Brau; H. M. Braun; B. Brelier; J. Bremer; R. Brenner; S. Bressler; D. Breton; N. D. Brett; D. Breton; F. M. Brochu; I. Brock; R. Brock; E. Brodet; F. Broggi; G. Brooijmans; W. K. Brooks; E. Brubaker; P. A. Bruckman de Renstrom; D. Bruncko; R. Bruneliere; S. Brunet; A. Bruni; G. Bruni; M. Bruschi; T. Buanes; F. B. Bucci; P. Buchholz; A. G. Buckley; I. A. Budagov; V. Buescher; L. Bugge; F. Bujor; O. Bulekov; M. Bunse; T. Buran; H. Burckhart; S. Burdin; S. Burke; E. Busato; C. P. Buszello; F. Butin; B. Butler; J. M. Butler; C. M. Buttar; J. M. Butterworth; T. Byatt; S. Cabrera Urban; D. Caforio; O. Cakir; P. Calafiura; G. Calderini; R. Calkins; L. P. Caloba; R. Calkins; D. Calvet; P. Camarri; M. Cambiaghi; D. Cameron; F. Campabadal Segura; S. Campana; M. Campanelli; V. Canale; J. Cantero; M. D. M. Capeans Garrido; I. Caprini; M. D. M. Capeans Garrido; M. Capua; R. Caputo; C. Caramarcu; R. Cardarelli; T. Carli; G. Carlino; L. Carminati; B. Caron; S. Caron; S. Carron Montero; A. A. Carter; J. R. Carter; J. Carvalho; D. Casadei; M. P. Casado; M. Cascella; C. Caso; A. M. Castaneda Hernadez; E. Castaneda Miranda; V. Castillo Gimenez; N. F. Castro; G. Cataldi; A. Catinaccio; J. R. Catmore; A. Catinaccio; G. Cattani; S. Caughron; D. Cauz; P. Cavalleri; D. Cavalli; M. Cavalli-Sforza; V. Cavasinni; A. Cazzato

2008-01-01

328

"Got Disc?" The "Ultimate" Experience in Physical Education  

ERIC Educational Resources Information Center

A quality physical education program is one in which students are exposed to and can participate in a variety of sports and activities. One activity that is increasing in popularity in and outside of physical education is the game of "Ultimate." Opportunities to play Ultimate are increasing rapidly in intramural programs and community and…

Johnson, Tyler G.; Darst, Paul W.; Brusseau, Timothy A.

2006-01-01

329

Two cultures? Experiences at the physics-biology interface.  

PubMed

'I didn't really think of this as moving into biology, but rather as exploring another venue in which to do physics.' John Hopfield provides a personal perspective on working on the border between physical and biological sciences. PMID:25292216

Hopfield, John J

2014-10-01

330

INSTITUTE OF PHYSICS PUBLISHING JOURNAL OF PHYSICS B: ATOMIC, MOLECULAR AND OPTICAL PHYSICS J. Phys. B: At. Mol. Opt. Phys. 37 (2004) 35513562 PII: S0953-4075(04)81883-2  

E-print Network

in an accelerating potential Timothy M Roach Physics Department, The College of the Holy Cross, Worcester, MA 01610 #12;3552 T M Roach y gUBU U atoms grating(a) (b) y Figure 1. (a) Cloud of atoms accelerated towards

Roach, Timothy

331

Tautomerization of Acetylacetone Enol. A Physical Organic Experiment in Kinetics and Thermodynamics.  

ERIC Educational Resources Information Center

Describes a physical organic experiment in thermodynamics and kinetics for undergraduate courses in organic chemistry, biochemistry, or physical chemistry. Details background information, solution preparations, equipment and methods, and the suggested experiments such as determination of general-base-catalytic coefficients and the Bronsted…

Spyridis, Greg T.; Meany, J. E.

1988-01-01

332

Atomic force microscopy silicon tips as photon tunneling sensors: a resonant evanescent coupling experiment  

NASA Astrophysics Data System (ADS)

Evanescent wave conversion by transparent dielectric nanoprobes has long been achieved in photon scanning tunneling microscopy experiments. Nevertheless, the exact mechanism (i.e., resolution limit) of this optical interaction is not satisfactorily explained theoretically nor evidenced experimentally. We study the ability of doped silicon atomic force microscopy tips to capture infrared near-field waves standing at the flat surface of a semiconductor (semi-insulating InP) material. It is shown that, unlike silicon nitride tips previously studied, the transmitted intensity of these silicon tips does not obey the classical frustrated total internal reflection model but a more complex dependence that involves a resonant tunneling transfer. An explanation is proposed that follows the theoretical predictions for the electromagnetic coupling between subwavelength objects.

Fillard, J. P.; Castagne, M.; Prioleau, C.

1995-07-01

333

X-ray measurements in helium-like atoms increased discrepancy between experiment and theoretical QED  

NASA Astrophysics Data System (ADS)

A recent 15 parts per million (ppm) experiment on muonic hydrogen ({{p}+}{{? }-}) found a major discrepancy with quantum electrodynamics (QED) and independent nuclear size determinations. Here we find a significant discrepancy in a different type of exotic atom: a medium-Z nucleus with two electrons. Investigation of the data collected is able to discriminate between available QED formulations and reveals a pattern of discrepancy of almost six standard errors of experimental results from the most recent theoretical predictions, with a functional dependence proportional to Zn where n? 4. In both the muonic and highly charged systems, the sign of the discrepancy is the same, with the measured transition energy higher than predicted. Some consequences are possible or probable, and some are more speculative. This may give insight into effective nuclear radii, the Rydberg, the fine-structure constant, or unexpectedly large QED terms.

Chantler, C. T.; Payne, A. T.; Gillaspy, J. D.; Hudson, L. T.; Smale, L. F.; Henins, A.; Kimpton, J. A.; Takacs, E.

2014-12-01

334

Experiences Teaching Inquiry-Based Physics to Prospective Elementary School Teachers  

Microsoft Academic Search

I will discuss my experience in teaching a laboratory-based introduction to physics intended for students in the elementary teacher education program at Mesa State College. This course was taught for three years and used the textbook and curriculum ``Physics by Inquiry'' developed by the Physics Education Group at the University of Washington. In this class students spend most of their

Bill Tiernan

2006-01-01

335

Nuclear Instruments and Methods in Physics Research A 499 (2003) 437468 The BRAHMS experiment at RHIC  

E-print Network

Nuclear Instruments and Methods in Physics Research A 499 (2003) 437­468 The BRAHMS experiment, USA f H. Niewodniczanski Institute of Nuclear Physics, Krak!ow, Poland g Cyclotron Institute, Texas A. Wadag , J. Westergaardb , A. Wielocha , I.S. Zgurad a M. Smoluchowski Institute of Physics, Jagiellonian

336

Thin film semiconductor nanomaterials and nanostructures prepared by physical vapour deposition: An atomic force microscopy study  

NASA Astrophysics Data System (ADS)

Amorphous/nanocrystalline SiOx/CdSe, GeS2/CdSe, SiOx/ZnSe and Se/CdSe amorphous multilayers (MLs) were grown by consecutive physical vapour deposition of the constituent materials at room substrate temperature. A step-by-step manner of deposition was applied for the preparation of each layer (2 10nm thick) of MLs. Surface morphology has been investigated by atomic force microscopy (AFM) in order to get information about ML interfaces. For a scanned area of 3.4×4?mSiOx/CdSe and GeS2/CdSe MLs showed surface roughness which is around three times greater than the roughness of SiOx/ZnSe MLs. This observation has been connected with effects of both film composition and deposition rate. For a scanned area of 250×250nm the roughness determined in all MLs displayed close values and a similar increase with the ML period. The latter has been related to the flexible structure of amorphous materials. The AFM results, in good agreement with previous X-ray diffraction and high resolution electron microscopy data, indicate that the application of step-by-step physical vapour deposition makes possible fabrication of various amorphous/nanocrystalline MLs with smooth interfaces and good artificial periodicity at low substrate temperatures.

Nesheva, D.; Petrova, A.; Stavrev, S.; Levi, Z.; Aneva, Z.

2007-05-01

337

Microfabrication and assembly of an integrated cavity QED and atom chip experiment  

Microsoft Academic Search

We have combined high-finesse optical resonators with an atom chip to study quantum atom optical systems. Fabry-Perot cavities in the single-atom strong coupling regime are aligned through micromachined holes in thinned silicon substrates that also house the microfabricated circuitry for magnetic trapping and transport of cold atoms. These high current capacity wires will allow for atoms to be confined well

Daniel Brooks; Tom Purdy; Dan Stamper-Kurn

2008-01-01

338

Berry phases for quadratic spin Hamiltonians taken from atomic and solid state physics: examples of Abelian gauge fields not connected to physical particles  

Microsoft Academic Search

This paper contains an evaluation of the Berry phases associated with the following class of nonlinear spin Hamiltonians : H (B, n ) = 03B3S S · B + 03B3Q((S · n)2 - S2\\/3), with B · n = 0. Examples of these Hamiltonians are given in Atomic and Solid State Physics. We compute exactly the Berry phases for S

C. Bouchiat

1989-01-01

339

Preliminary design of two Space Shuttle fluid physics experiments  

NASA Technical Reports Server (NTRS)

The mid-deck lockers of the STS and the requirements for operating an experiment in this region are described. The design of the surface tension induced convection and the free surface phenomenon experiments use a two locker volume with an experiment unique structure as a housing. A manual mode is developed for the Surface Tension Induced Convection experiment. The fluid is maintained in an accumulator pre-flight. To begin the experiment, a pressurized gas drives the fluid into the experiment container. The fluid is an inert silicone oil and the container material is selected to be comparable. A wound wire heater, located axisymmetrically above the fluid can deliver three wattages to a spot on the fluid surface. These wattages vary from 1-15 watts. Fluid flow is observed through the motion of particles in the fluid. A 5 mw He/Ne laser illuminates the container. Scattered light is recorded by a 35mm camera. The free surface phenomena experiment consists of a trapezoidal cell which is filled from the bottom. The fluid is photographed at high speed using a 35mm camera which incorporated the entire cell length in the field of view. The assembly can incorporate four cells in one flight. For each experiment, an electronics block diagram is provided. A control panel concept is given for the surface induced convection. Both experiments are within the mid-deck locker weight and c-g limits.

Gat, N.; Kropp, J. L.

1984-01-01

340

Event-Based Simulation of Quantum Physics Experiments  

NASA Astrophysics Data System (ADS)

We review an event-based simulation approach which reproduces the statistical distributions of wave theory not by requiring the knowledge of the solution of the wave equation of the whole system but by generating detection events oneby- one according to an unknown distribution. We illustrate its applicability to various single photon and single neutron interferometry experiments and to two Bell-test experiments, a single-photon Einstein-Podolsky-Rosen experiment employing post-selection for photon pair identification and a single-neutron Bell test interferometry experiment with nearly 100% detection efficiency.

Michielsen, Kristel; de Raedt, Hans

2015-10-01

341

Simple Laser Scattering Experiment for Biology-Oriented Physics Labs.  

ERIC Educational Resources Information Center

Describes a physics exercise designed for biology and premed majors. The activity is a low intensity laser light scattering laboratory exercise to determine the diameter of micron-sized latex spheres (simulated microbes) in water suspension. (GA)

Orwig, L.; Schrank, G.

1979-01-01

342

From physical to virtual : extending the gallery experience online  

E-print Network

This thesis is an exploration of the ways in which interactive features in the virtual space can be developed to complement physical museum exhibitions, as well as create opportunities for museums to reach broader audiences. ...

Ho, Moneta Kwok-Ching, 1976-

2004-01-01

343

Physical adsorption: rare gas atoms on solid surfaces. Progress report, June 1, 1980-May 31, 1981  

SciTech Connect

This project has entailed investigation of three areas during the current term: physical adsorption, photostimulated field emission (PSE), and phonon reflection at interfaces. The principal effort has been directed toward understanding interactions associated with physical adsorption and the associated properties of a film. The specific topics pursued include the detailed form of the long range interaction, the configuration space wave function, and the interaction between adatoms. Experimental confirmation of the last two come from neutron scattering and thermodynamic measurements, respectively. The research in PSE has yielded results which improve upon previous calculations. There is, however, a remaining disagreement with experiment; suggestions for the origin are discussed. The phonon reflection work is directed toward understanding the role of surface roughness, an important factor in increasing the energy transmission across interfaces. A formalism has been developed which will be evaluated in the future.

Cole, M.W.

1981-02-01

344

The use of cylindrical lenses in easy experiments for physics education and the magic arts  

NASA Astrophysics Data System (ADS)

The purpose of this article is to present the properties of cylindrical lenses and provide some examples of their use in easy school physics experiments. Such experiments could be successfully conducted in the context of science education, in fun experiments that teach physics and in science fair projects, or used to entertain an audience by staging tricks, effects or illusions of seemingly impossible or supernatural feats.

Bednarek, Stanis?aw; Krysiak, Jerzy

2011-09-01

345

Ground-Laboratory to In-Space Atomic Oxygen Correlation for the Polymer Erosion and Contamination Experiment (PEACE) Polymers  

NASA Technical Reports Server (NTRS)

The Materials International Space Station Experiment 2 (MISSE 2) Polymer Erosion and Contamination Experiment (PEACE) polymers were exposed to the environment of low Earth orbit (LEO) for 3.95 years from 2001 to 2005. There were 41 different PEACE polymers, which were flown on the exterior of the International Space Station (ISS) in order to determine their atomic oxygen erosion yields. In LEO, atomic oxygen is an environmental durability threat, particularly for long duration mission exposures. Although spaceflight experiments, such as the MISSE 2 PEACE experiment, are ideal for determining LEO environmental durability of spacecraft materials, ground-laboratory testing is often relied upon for durability evaluation and prediction. Unfortunately, significant differences exist between LEO atomic oxygen exposure and atomic oxygen exposure in ground-laboratory facilities. These differences include variations in species, energies, thermal exposures and radiation exposures, all of which may result in different reactions and erosion rates. In an effort to improve the accuracy of ground-based durability testing, ground-laboratory to in-space atomic oxygen correlation experiments have been conducted. In these tests, the atomic oxygen erosion yields of the PEACE polymers were determined relative to Kapton H using a radio-frequency (RF) plasma asher (operated on air). The asher erosion yields were compared to the MISSE 2 PEACE erosion yields to determine the correlation between erosion rates in the two environments. This paper provides a summary of the MISSE 2 PEACE experiment; it reviews the specific polymers tested as well as the techniques used to determine erosion yield in the asher, and it provides a correlation between the space and ground laboratory erosion yield values. Using the PEACE polymers asher to in-space erosion yield ratios will allow more accurate in-space materials performance predictions to be made based on plasma asher durability evaluation.

Stambler, Arielle H.; Inoshita, Karen E.; Roberts, Lily M.; Barbagallo, Claire E.; deGroh, Kim K.; Banks, Bruce A.

2011-01-01

346

Getting Physical with Your Chemistry: Mechanically Investigating Local Structure and Properties of Surfaces with the Atomic Force Microscope  

ERIC Educational Resources Information Center

Atomic force microscope (AFM) investigates mechanically the chemical properties of individual molecules, surfaces, and materials using suitably designed probes. The current state of the art of AFM in terms of imaging, force measurement, and sample manipulation and its application to physical chemistry is discussed.

Heinz, William F.; Hoh, Jan H.

2005-01-01

347

ANL-E Health Physics experience with D and D  

SciTech Connect

The Argonne National Laboratory--East (ANL-E) Health Physics Section provides direct and/or oversight support to various D&D projects at ANL-E. The health physics problems encountered have been challenging, primarily because they involved the potential for high internal exposures as well as actual high external exposures. The lessons learned are applicable to other radiological facilities. A number of D&D projects being conducted concurrently at ANL-E are described. The problems encountered are then categorized, and lessons learned and recommendations are provided. The main focus will be limited to the support and technical assistance provided by personnel from the ANL Health Physics Section during the course of the work activities.

Baker, S.I.; Mosho, G.D.; Munyon, W.J.; Murdoch, B.T.; Sholeen, C.M.; Shuman, J.P.

1996-04-01

348

Surface interaction mechanisms of 5eV atomic oxygen: Data analysis from the UAH experiment on STS-8  

NASA Technical Reports Server (NTRS)

The University of Alabama in Huntsville (UAH) experiment which flew on the STS-8 mission had several objectives which were mostly of a speculative nature since so little was known of the processes of interest. The experiment provided original, if limited, data on: (1) oxidation of metal surfaces, (2) reaction rates of atomic oxygen with carbon and other surfaces and the dependence of these rates on temperature, and (3) the angular distribution of 5eV atoms scattered off a solid surface. Provided is a review of the results, with reference given to fuller published accounts where these are available.

Gregory, J. C.

1987-01-01

349

Spina Bifida Experience: The Importance of Physical Activity  

MedlinePLUS Videos and Cool Tools

... Activity Your browser does not support iFrames. Related Videos Spina Bifida Experience Developing Independence Managing Your Own Medical Care More Videos Video Archive Find more NCBDDD videos to watch ...

350

Stern-Gerlach Experiments and Complex Numbers in Quantum Physics  

E-print Network

It is often stated that complex numbers are essential in quantum theory. In this article, the need for complex numbers in quantum theory is motivated using the results of tandem Stern-Gerlach experiments

S. Sivakumar

2012-07-09

351

Superconducting magnet protection system for the tokamak physics experiment  

NASA Astrophysics Data System (ADS)

The TPX tokamak must protect 30 superconducting magnets during a complex, pulsed physics scenario. 2.0 MA plasma vertical disruptions will occur at unpredictable intervals. These should not cause quench, but will be difficult to distinguish from quench. A redundant, multiple signal protection system combines conventional voltage taps with signals from cowound conductors, pressure and flow sensors.

Schultz, Joel H.; Chaniotakis, E.; Pillsbury, R. D., Jr.; Wang, P. W.; Citrolo, J.; Neumeyer, C.; Chaplin, M.; Hassenzahl, W. V.

1994-07-01

352

Atom Chips  

E-print Network

Atoms can be trapped and guided using nano-fabricated wires on surfaces, achieving the scales required by quantum information proposals. These Atom Chips form the basis for robust and widespread applications of cold atoms ranging from atom optics to fundamental questions in mesoscopic physics, and possibly quantum information systems.

Ron Folman; Peter Krüger; Donatella Cassettari; Björn Hessmo; Thomas Maier; Jörg Schmiedmayer

1999-12-23

353

PHYSICAL REVIEW A 87, 063412 (2013) Rb atoms in a blue-detuned dipole trap: Coherence and ground-state differential ac Stark shift  

E-print Network

PHYSICAL REVIEW A 87, 063412 (2013) Rb atoms in a blue-detuned dipole trap: Coherence and ground) Blue-detuned dipole traps and their ability to preserve atomic coherences are interesting for precision of the ground-state hyperfine splitting in 87 Rb atoms confined in a dynamic blue-detuned dipole trap. We

Orozco, Luis A.

354

Optics and interferometry with atoms and molecules  

SciTech Connect

Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic clocks. Atom interferometry is now reaching maturity as a powerful art with many applications in modern science. In this review the basic tools for coherent atom optics are described including diffraction by nanostructures and laser light, three-grating interferometers, and double wells on atom chips. Scientific advances in a broad range of fields that have resulted from the application of atom interferometers are reviewed. These are grouped in three categories: (i) fundamental quantum science, (ii) precision metrology, and (iii) atomic and molecular physics. Although some experiments with Bose-Einstein condensates are included, the focus of the review is on linear matter wave optics, i.e., phenomena where each single atom interferes with itself.

Cronin, Alexander D.; Schmiedmayer, Joerg; Pritchard, David E. [Department of Physics, University of Arizona, Tucson, Arizona 85721 (United States); Atominstitut Oesterreichischen Universitaeten, TU-Wien (Austria); Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2009-07-15

355

atomic spectra 1 Atomic Spectra  

E-print Network

Physics, pp. 88-93 (Rutherford nuclear model), 93-106 (atomic structure and electron spectra) 2. D. W 3. Beiser: Concepts of Modern Physics, pp. 131-161 (atomic structure and electron spectra) 4. E. Lamb, Jr. and R. C. Retherford: The Structure of the Hydrogen Atom by a Microwave Method, Phys

Glashausser, Charles

356

HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS  

SciTech Connect

The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

2010-03-16

357

HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS  

SciTech Connect

The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

Bieniosek, F.M.; Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

2008-08-01

358

An analysis of a two-atom double-slit experiment based on environment-induced measurements  

E-print Network

To investigate the effect of a classical environment on a quantum mechanical system we consider two two-level atoms in a free radiation field in the presence of a screen. By assuming that the screen causes continuous ideal measurements on the free radiation field we derive a quantum jump description for the state of the atoms. Our results are consistent with the master equations for dipole interacting atoms, but give more insight in the time evolution of a single system. To illustrate this we derive a necessary and sufficient criterion for interference in a two-atom double-slit experiment and analyse bunching in the statistics of photons emitted in a certain direction.

Christian Schoen; Almut Beige

2001-05-01

359

Atomic and molecular physics of plasma-based environmental technologies for abatement of volatile organic compounds  

SciTech Connect

Non-thermal plasma techniques represent a new generation of air emission control technology that potentially could treat large-volume emissions containing dilute concentrations of volatile organic compounds (VOCs). In order to apply non-thermal plasmas in an industrial scale, it is important to establish the electrical power requirements and byproducts of the process. There is a need for reliable data concerning the primary decomposition mechanisms and subsequent chemical kinetics associated with non-thermal processing of VOCs. There are many basic atomic and molecular physics issues that are essential in evaluating the economic performance of non- thermal plasma reactors. These studies are important in understanding how the input electrical power is dissipated in the plasma and how efficiently it is converted to the production of the plasma species (radicals, ions, or electrons) responsible for the decomposition of the VOCs. This paper will present results from the basic experimental and theoretical studies aimed at identifying the reaction mechanisms responsible for the primary decomposition of various types of VOCs.

Penetrante, B.M.; Hsiao, M.C.; Bardsley, J.N.; Merritt, B.T.; Vogtlin, G.E. [Lawrence Livermore National Lab., CA (United States); Kuthi, A. [Plasma and Materials Technologies, Inc., Chatsworth, CA (United States); Burkhart, C.P.; Bayless, J.R. [First Point Scientific, Inc., Agoura Hills, CA (United States)

1996-08-01

360

Simulating Educational Physical Experiments in Augmented Reality Hannes Kaufmann  

E-print Network

in everyday life. The three fundamental laws of motion which were formulated by Isaac Newton (1642 - 1727 are based on Newton's laws of motion. Therefore the authors developed an educational augmented reality (AR of Technology Figure 1: Left: An experiment simulating the motion of a car crankshaft. Right: A centrifugal

361

The Design of Learning Experiences: A Connection to Physical Environments.  

ERIC Educational Resources Information Center

The school environment must create a rich, beautiful, dynamic, meaningful experience for students to learn; however, architects, school boards, and the state focus almost exclusively only on the building when making design decisions. This document lists specific aspects to developing a visionary campus: one that provides a three-dimensional…

Stueck, Lawrence E.; Tanner, C. Kenneth

362

Experiments in Molecular Physics with an Acoustic Interferometer  

ERIC Educational Resources Information Center

A device which provides an inexpensive means for making precise studies of the kinetics of gas molecules is discussed. Two experiments are described: (1) Measurement of the vibrational relaxation time of gas molecules and (2) determination of intermolecular forces in molecules. (Author/DF)

Rossing, Thomas D.

1973-01-01

363

Skylab Experiments, Volume 5, Astronomy and Space Physics.  

ERIC Educational Resources Information Center

Basic knowledge about Skylab experiments is presented in this book, one of a series, for the purpose of informing high school teachers about scientific research performed in orbit and enabling the teachers to broaden their basis for material selection. This fifth volume is concerned with studies of our own and other galaxies and effects of solar…

National Aeronautics and Space Administration, Washington, DC.

364

Cation Hydration Constants by Proton NMR: A Physical Chemistry Experiment.  

ERIC Educational Resources Information Center

Studies the polarization effect on water by cations and anions. Describes an experiment to illustrate the polarization effect of sodium, lithium, calcium, and strontium ions on the water molecule in the hydration spheres of the ions. Analysis is performed by proton NMR. (MVL)

Smith, Robert L.; And Others

1988-01-01

365

A Simple LIBS (Laser-Induced Breakdown Spectroscopy) Laboratory Experiment to Introduce Undergraduates to Calibration Functions and Atomic Spectroscopy  

ERIC Educational Resources Information Center

This laboratory experiment introduces students to a different type of atomic spectroscopy: laser-induced breakdown spectroscopy (LIBS). LIBS uses a laser-generated spark to excite the sample; once excited, the elemental emission is spectrally resolved and detected. The students use LIBS to analyze a series of standard synthetic silicate samples…

Chinni, Rosemarie C.

2012-01-01

366

How Many Atomic Layers of Zinc Are in a Galvanized Iron Coating? An Experiment for General Chemistry Laboratory  

ERIC Educational Resources Information Center

This article describes an experiment using a novel gasometric assembly to determine the thickness and number of atomic layers of zinc coating on galvanized iron substrates. Students solved this problem through three stages. In the first stage, students were encouraged to find a suitable acidic concentration through the guided-inquiry approach. In…

Yang, Shui-Ping

2007-01-01

367

Echoing with the Voices of Victims: Reflection on Vietnamese Lessons on the Japanese Experiences of Atomic Bombs  

ERIC Educational Resources Information Center

This article explores the case of a Vietnamese teacher whose conception of teaching changed greatly following a short but intensive series of lessons based on the Japanese experiences with atomic bombs. The following three issues are considered: 1) what types of efforts teachers should make to increase the depth of their lessons, on the basis of…

Saito, Eisuke; Hien, Do Thi; Hang, Khong Thi Diem

2010-01-01

368

Folding peptides and proteins with all-atom physics: methods and applications  

NASA Astrophysics Data System (ADS)

Computational methods offer powerful tools for investigating proteins and peptides at the molecular-level; however, it has proven challenging to reproduce the long time scale folding processes of these molecules at a level that is both faithful to the atomic driving forces and attainable with modern commodity cluster computing. Alternatively, the past decade has seen significant progress in using bioinformatics-based approaches to infer the three dimensional native structures of proteins, drawing upon extensive knowledge databases of known protein structures [1]. These methods work remarkably well when a homologous protein can be found to provide a structural template for a candidate sequence. However, in cases where homology to database proteins is low, where the folding pathway is of interest, or where conformational flexibility is substantial---as in many emerging protein and peptide technologies---bioinformatics methods perform poorly. There is therefore great interest in seeing purely physics-based approaches succeed. We discuss a purely physics-based, database-free folding method, relying on proper thermal sampling (replica exchange molecular dynamics) and molecular potential energy functions. In order to surmount the tremendous computational demands of all-atom folding simulations, our approach implements a conformational search strategy based on a putative protein folding mechanism called zipping and assembly [2-4]. That is, we explicitly seek out potential folding pathways inferred from short simulations, and iteratively pursue all such routes by coaxing a polypeptide chain along them. The method is called the Zipping and Assembly Method (ZAM) and it works in two parts: (1) the full polypeptide chain is broken into small fragments that are first simulated independently and then successively re-assembled into larger segments with further sampling, and (2) consistently stable structure in fragments is detected and locked into place, in order to avoid re-sampling those degrees of freedom in subsequent steps. ZAM pursues all potential folding routes it finds, which may be mutually exclusive, and it ranks these by calculating free energies along the way. Importantly, it gives full conformational ensembles and folding pathways, features not captured by bioinformatics approaches. We also discuss ways in which the structural ensembles and folding pathways of ZAM can facilitate the rational design of peptide technologies. In particular, we examine the coupling of ZAM-produced structures with coarse-grained theories of transport and association, in order to model the interactions of peptides with membranes (for insertion processes), proteins (for binding processes), and other peptides (for aggregation processes). Importantly, this approach is able to capture highly sequence-specific effects due to the atomistic nature of the ZAM folding simulations, providing a predictive tool for targeted sequence mutations. 1. J. Moult, A decade of CASP: progress, bottlenecks and prognosis in protein structure prediction, Curr. Opin. Struct. Biol. 15, (2005). 2. K.M. Fiebig and K.A. Dill, Protein core assembly processes, J. Chem. Phys. 98, (1993). 3. S.B. Ozkan, G.H.A. Wu, J.D. Chodera, and K.A. Dill, Protein folding by zipping and assembly, Proc. Natl. Acad. Sci. U. S. A. 104, (2007). 4. M.S. Shell, S.B. Ozkan, V.A. Voelz, G.H.A. Wu, and K. Dill, Can molecular physics predict the native structures of globular proteins?, under review, (2007).

Shell, M. Scott

2008-03-01

369

Viscosity experiments: physical controls and implications for volcanic hazards  

NSDL National Science Digital Library

Teaching students about viscosity is easy, effective and fun. It is a topic that is conducive to a range of teaching and learning styles, and allows for the integration of theory, experiments, and calculations. During the course of this exercise, students are required to make predictions about the outcomes of experiments, quantitatively document the results of their experiments, calculate viscosities using the Jeffreys equation (Jeffreys 1925; Nichols 1939; Cas and Wright 1987), and extrapolate the concepts learned from their laboratory results to natural conditions appropriate for silicate magmas and lavas. Students are also introduced to Ken Wohletz's freeware program MAGMA (no longer available), which allows them to determine viscosities for magma and lava compositions, and are required to do some simple graphical analysis of the effects of composition, dissolved H2O, and % solids on magma and lava viscosity using the MAGMA calculations. Viscosity is important for students at all levels of earth science to understand because it is a critical control on morphologies of volcanoes, velocities of lava flows, eruptive styles (effusive versus explosive), and ascent velocities of magmas within the earth. The objectives of the lab are for students to: learn about the rheological property called viscosity and some of the factors that affect it; think about and discuss ways in which viscosity controls styles of eruptions and relates to volcanic hazards; and practice quantitative skills. I have used the viscosity experiments as a classroom demonstration in introductory geology courses, as one part of a more extensive lab on volcanoes in introductory geology courses, and as a more intensive viscosity lab for introductory petrology courses. Generally the students do this exercise after they have had at least one introductory lecture on volcanoes, so that they are familiar with several basic terms, including viscosity, lava, magma, as well as some basic igneous rock terms (basalt, andesite, rhyolite). Over the fives years that I have been using the experiments, students at all levels have commented that the experiments are some of the most memorable, interesting and fun parts of my courses. I would welcome any direct student or instructor feedback for improvements or additions to the exercises (edwardsb AT dickinson.edu).

Edwards, Ben

370

PHYSICAL REVIEW C VOLUME 27, NUMBER 4 APRIL 1983 Atomic final-state interactions in tritium decay  

E-print Network

. D. Williams and S. E. Koonin W. K. Kellogg Radiation Laboratory, California Institute of Technology. [ RADIOACTIVITY 3H; atomic final states, neutrino mass. ] In a recent experiment, Lubimov et al. ' attemped interaction V~, the ampli- tude for this process is Tri= (Pf I Vs I@';) where 4~ is the initial tritium ls

Williams, Roy

371

Walter Fendt Physics Applets: Newton's Second Law Experiment  

NSDL National Science Digital Library

This Java applet simulates an air track glider, a low-friction device commonly used to study Newton's Second Law of Motion and collisions. A mass sliding on the horizontal track surface is connected by a string to a hanging mass. The value of the two masses and the coefficient of friction can be set by the user. A timer is provided to gather data for the motion of the sliding mass as a function of time. This applet is a part of a large collection of physics applets, available in a wide range of languages.

Fendt, Walter

2007-02-05

372

Diagnostics for ion beam driven high energy density physics experiments.  

PubMed

Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30 mA K(+) beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multichannel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (Velocity Interferometer System for Any Reflector), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II. PMID:21033977

Bieniosek, F M; Henestroza, E; Lidia, S; Ni, P A

2010-10-01

373

Strange hadronic physics in electroproduction experiments at the Mainz Microtron  

NASA Astrophysics Data System (ADS)

Present and future research into the electroproduction of strangeness plays an important role at Mainz Microtron MAMI. With the KAOS spectrometer for kaon detection operated in the multi-spectrometer facility first cross section measurements of the exclusive p(e,e'K+)?,?0 reactions at low-momentum transfers have been performed. These measurements have clearly discriminated between effective Lagrangian models for photo- and electroproduction of strangeness. Recently, the KAOS spectrometer was upgraded to a double-arm spectrometer for the measurement of elementary cross sections at very forward scattering angles and for the missing mass spectroscopy of hypernuclear states. In parallel, pioneering experiments on decay-pion spectroscopy of electroproduced hypernuclei were carried out at MAMI. Future experiments will on the one side address the cross section of the elementary process with polarized beam and on the other side continue the hypernuclear spectroscopy with different light nuclear targets.

Achenbach, P.; Esser, A.; Ayerbe Gayoso, C.; Böhm, R.; Borodina, O.; Bosnar, D.; Bozkurt, V.; Bydžovský, P.; Debenjak, L.; Distler, M. O.; Friš?i?, I.; Fujii, Y.; Gogami, T.; Gómez Rodríguez, M.; Hashimoto, O.; Hirose, S.; Kim, E.; Margaryan, A.; Merkel, H.; Müller, U.; Nagao, S.; Nakamura, S. N.; Pochodzalla, J.; Rappold, C.; Reinhold, J.; Saito, T. R.; Sanchez Lorente, A.; Sánchez Majos, S.; Schlimme, B. S.; Schoth, M.; Schulz, F.; Sfienti, C.; Širca, S.; Tang, L.; Thiel, M.; Tsukada, K.; A1 Collaboration

2012-05-01

374

Infrared Spectra of Simple Inorganic Ion Pairs in Solid Solution: A Physical Inorganic Chemistry Experiment.  

ERIC Educational Resources Information Center

Presents a physical inorganic experiment in which large single crystals of the alkali halides doped with divalent ion impurities are prepared easily. Demonstrates the ion pairing of inorganic ions in solid solution. (CS)

Miller, Philip J.; Tong, William G.

1980-01-01

375

Efficient continuous-duty Bitter-type electromagnets for cold atom experiments.  

PubMed

We present the design, construction, and characterization of Bitter-type electromagnets which can generate high magnetic fields under continuous operation with efficient heat removal for cold atom experiments. The electromagnets are constructed from a stack of alternating layers consisting of copper arcs and insulating polyester spacers. Efficient cooling of the copper is achieved via parallel rectangular water cooling channels between copper layers with low resistance to flow; a high ratio of the water-cooled surface area to the volume of copper ensures a short length scale (~1 mm) to extract dissipated heat. High copper fraction per layer ensures high magnetic field generated per unit energy dissipated. The ensemble is highly scalable and compressed to create a watertight seal without epoxy. From our measurements, a peak field of 770 G is generated 14 mm away from a single electromagnet with a current of 400 A and a total power dissipation of 1.6 kW. With cooling water flowing at 3.8 l/min, the coil temperature only increases by 7 °C under continuous operation. PMID:24182143

Sabulsky, Dylan O; Parker, Colin V; Gemelke, Nathan D; Chin, Cheng

2013-10-01

376

Laser-Plasma Interaction Physics during OMEGA Implosion Experiments  

Microsoft Academic Search

Direct-drive implosion experiments on the 60-beam, 30-kJ, UV OMEGA laser facility have shown scattered light in the region near the incident laser frequency (omega_0)** as well as the regions corresponding to stimulated Raman scattering (SRS) and the two-plasmon-decay instability (omega_0\\/2)**. The backscattered light near (omega_0)** ranges from 5% to 10% into 4pi*. Its spectral structure is complex but can be

W. Seka; D. D. Meyerhofer; A. V. Chirokikh; D. K. Bradley; J. Delettrez; R. S. Craxton; A. Simon

1997-01-01

377

High energy physics experiment triggers and the trustworthiness of software  

SciTech Connect

For all the time and frustration that high energy physicists expend interacting with computers, it is surprising that more attention is not paid to the critical role computers play in the science. With large, expensive colliding beam experiments now dependent on complex programs working at startup, questions of reliability -- the trustworthiness of software -- need to be addressed. This issue is most acute in triggers, used to select data to record -- and data to discard -- in the real time environment of an experiment. High level triggers are built on codes that now exceed 2 million source lines -- and for the first time experiments are truly dependent on them. This dependency will increase at the accelerators planned for the new millennium (SSC and LHC), where cost and other pressures will reduce tolerance for first run problems, and the high luminosities will make this on-line data selection essential. A sense of this incipient crisis motivated the unusual juxtaposition to topics in these lectures. 37 refs., 1 fig.

Nash, T.

1991-10-01

378

Experimenting with the virtual environment Moodle in Physics Education  

NASA Astrophysics Data System (ADS)

The master's program in Physics Education of the Catholic University in the state of Minas Gerais, Brazil, includes the discipline ``Digital technologies in Physics education.'' The main goal of this discipline is to discuss the role of Information and Communication Technology (ICT) in the process of learning-teaching science. We introduce our students to several virtual platforms, both free and commercial, discussing their functionality and features. We encourage our students to get in touch with computer tools and resources by planning their own computer based course using the Moodle platform. We discuss different patterns of virtual environment courses, whose proposals are centered mainly in the students, or teacher-centered or even system-centered. The student is free to choose between only one topic and a year course to work with, since their interests vary from learning something more about a specific subject to a complete e-learning course covering the entire school year. (The courses are available online in the address sitesinf01.pucmg.br/moodle. Participation only requires filling out an application form.) After three editions of this discipline, we have several courses available. We realize that students tend to focus on traditional methods, always preserving their role as knowledge-givers. In conclusion, we can say that, in spite of exhaustive discussion about autonomy involved with ICTs abilities, most of the students used the new virtual medium to organize traditional teacher-centered courses.

Martins, Maria Ines; Dickman, Adriana

2008-03-01

379

Computer simulations for lab experiences in secondary physics  

NASA Astrophysics Data System (ADS)

Physical science instruction often involves modeling natural systems, such as electricity that possess particles which are invisible to the unaided eye. The effect of these particles' motion is observable, but the particles are not directly observable to humans. Simulations have been developed in physics, chemistry and biology that, under certain circumstances, have been found to allow students to gain insight into the operation of the systems they model. This study compared the use of a DC circuit simulation, a modified simulation, static graphics, and traditional bulbs and wires to compare gains in DC circuit knowledge as measured by the DIRECT instrument, a multiple choice instrument previously developed to assess DC circuit knowledge. Gender, prior DC circuit knowledge and subsets of DC circuit knowledge of students were also compared. The population (n=166) was comprised of high school freshmen students from an eastern Kentucky public school with a population of 1100 students and followed a quantitative quasi experimental research design. Differences between treatment groups were not statistically significant. Keywords: Simulations, Static Images, Science Education, DC Circuit Instruction, Phet.

Murphy, David Shannon

380

Positron Physics  

NASA Astrophysics Data System (ADS)

This book provides a comprehensive and up-to-date account of the field of low energy positrons and positronium within atomic and molecular physics. It begins with an introduction to the field, discussing the background to low energy positron beams, and then covers topics such as total scattering cross sections, elastic scattering, positronium formation, excitation and ionization, annihilation and positronium interactions. Each chapter contains a blend of theory and experiment, giving a balanced treatment of all the topics. The book will be useful for graduate students and researchers in physics and chemistry. It is ideal for those wishing to gain rapid, in-depth knowledge of this unique branch of atomic physics.

Charlton, M.; Humberston, J. W.

2000-12-01

381

The Nature and Role of Thought Experiments in Solving Conceptual Physics Problems  

ERIC Educational Resources Information Center

This study describes the possible variations of thought experiments in terms of their nature, purpose, and reasoning resources adopted during the solution of conceptual physics problems. A phenomenographic research approach was adopted for this study. Three groups of participants with varying levels of physics knowledge--low, medium, and high…

Kösem, Sule Dönertas; Özdemir, Ömer Faruk

2014-01-01

382

Space Physics in Greece: Experience and Future Prospects Ioannis A. Daglis, Anastasios Anastasiadis and Georgia Tsiropoula  

E-print Network

Space Physics in Greece: Experience and Future Prospects Ioannis A. Daglis, Anastasios Anastasiadis and Georgia Tsiropoula National Observatory of Athens, Institute of Ionospheric and Space Research, Penteli Engineering, Xanthi, Greece Abstract. Space Physics was born with the launch of the first artifi­ cial

Anastasiadis, Anastasios

383

Learning to teach physics through inquiry: The lived experience of a graduate teaching assistant  

Microsoft Academic Search

This investigation examines the difficulties encountered by one graduate teaching assistant as she taught Physics for Elementary Education, a large-enrollment, inquiry-based science course taught at a public Midwestern university. The methodological approach of hermeneutic phenomenology served as the lens to investigate the research question, What is the lived experience of a graduate teaching assistant as she learned to teach physics

Mark J. Volkmann; Marta Zgagacz

2004-01-01

384

Digital Video: The Impact on Children's Learning Experiences in Primary Physical Education  

ERIC Educational Resources Information Center

Technology can support teaching, learning and assessment in physical education. The purpose of this study was to examine children's perspectives and experiences of using digital video in primary physical education. The impact on motivation, feedback, self-assessment and learning was examined. Twenty-three children aged 9-10 years participated…

O'Loughlin, Joe; Chroinin, Deirdre Ni; O'Grady, David

2013-01-01

385

Fifth Grade Students' Experiences Participating in Active Gaming in Physical Education: The Persistence to Game  

ERIC Educational Resources Information Center

Although video games are often associated with sedentary behaviors, active gaming is a new genre that requires children to become physically active while playing the games. In this study six fifth grade students' experiences participating in active gaming in eight-week physical education classes were explored. Qualitative methods of interviews,…

Hansen, Lisa; Sanders, Steve

2010-01-01

386

Alpha particle physics in a tokamak burning plasma experiment  

NASA Astrophysics Data System (ADS)

Much is known about the behavior of energetic ions in tokamak devices but much remains to be understood. Single-particle effects are well understood and provide a firm basis for extrapolation to a burning plasma. In contrast, collective effects involving fast ions are more poorly understood and extrapolations are unreliable. Collective modes of concern include toroidicity-induced and ellipticity-induced Alfvén eigenmodes, kinetic ballooning modes, and internal kink modes. In addition to these magnetohydrodynamic normal modes, there are also energetic particle modes characterized by strong dependence on the fast-ion distribution function. Although many issues are important areas of study in current experiments, five issues distinguish burning plasma experiments. First, the energetic alphas are not the dominant source of free energy for the instabilities unless the fusion power exceeds the heating power by a factor of 10. Second, the damping of the instabilities depends sensitively on mode coupling to other heavily-damped waves. The magnitude of this coupling is expected to depend on the normalized thermal gyroradius, which is much smaller in a reactor. Third, in a reactor, both the radial extent of the instabilities and the fast-ion orbit contract relative to current experiments, so the fast-ion transport will change. Fourth, when instability occurs, a larger number of modes are unstable, so the mechanism of nonlinear saturation could shift from fast-ion transport to mode coupling. Fifth, because of the extreme sensitivity of energetic particle modes to the distribution function, an isotropic alpha particle distribution function differs from anisotropic fast-ion populations.

Heidbrink, W. W.

2002-05-01

387

Hypernuclear physics studies of the PANDA experiment at FAIR  

NASA Astrophysics Data System (ADS)

Hypernuclear research will be one of the main topics addressed by the PANDA experiment at the planned Facility for Antiproton and Ion Research FAIR at Darmstadt (Germany). http://www. gsi.de, http://www.gsi.de/fair/. Thanks to the use of stored overline {p} beams, copious production of double ? hypernuclei is expected at the PANDA experiment, which will enable high precision ? spectroscopy of such nuclei for the first time, and consequently a unique chance to explore the hyperon-hyperon interaction. In particular, ambiguities of past experiments in determining the strength of the ?? interaction will be avoided thanks to the excellent energy precision of a few keV (FWHM) achieved by germanium detectors. Such a resolution capability is particularly needed to resolve the small energy spacing of the order of (10-100) keV, which is characteristic from the spin doublet in hypernuclei the so -called "hypernuclear fine structure". In comparison to previous experiments, PANDA will benefit from a novel technique to assign the various observable ?-transitions in a unique way to specific double hypernuclei by exploring various light targets. Nevertheless, the ability to carry out unique assignments requires a devoted hypernuclear detector setup. This consists of a primary nuclear target for the production of {? }-+overline {? } pairs, a secondary active target for the hypernuclei formation and the identification of associated decay products and a germanium array detector to perform ? spectroscopy. Moreover, one of the most challenging issues of this project is the fact that all detector systems need to operate in the presence of a high magnetic field and a large hadronic background. Accordingly, the need of an innovative detector concept will require dramatic improvements to fulfil these conditions and that will likely lead to a new generation of detectors. In the present talk details concerning the current status of the activities related to the detector developments for this challenging programme will be given. Among these improvements is the new concept for a cooling system for the germanium detector based on a electro-mechanical device. In the present work, the cooling efficiency of such devices has been successfully tested, showing their capability to reach liquid nitrogen temperatures and therefore the possibility to use them as a good alternative to the standard liquid nitrogen dewars. Furthermore, since the momentum resolution of low momentum particles is crucial for the unique identification of hypernuclei, an analysis procedure for improving the momentum resolution in few layer silicon based trackers is presented.

Sanchez Lorente, Alicia

2014-09-01

388

Pixel multichip module design for a high energy physics experiment  

SciTech Connect

At Fermilab, a pixel detector multichip module is being developed for the BTeV experiment. The module is composed of three layers. The lowest layer is formed by the readout integrated circuits (ICs). The back of the ICs is in thermal contact with the supporting structure, while the top is flip-chip bump-bonded to the pixel sensor. A low mass flex-circuit interconnect is glued on the top of this assembly, and the readout IC pads are wire-bounded to the circuit. This paper presents recent results on the development of a multichip module prototype and summarizes its performance characteristics.

Guilherme Cardoso et al.

2003-11-05

389

Energetic Neutral Atoms from the Moon: Populations, physics, applications, and the future  

NASA Astrophysics Data System (ADS)

Coexistence of plasma particles and neutral materials in space creates energetic neutral atoms (ENAs). For example, when solar wind plasma interacts with the lunar surface, ENA production is expected. We review recent investigations of the Moon-associated ENAs observed by a lunar orbiter, Chandrayaan-1, and discuss lessons learnt from the experiment. Intensive observations were conducted by the Chandrayaan-1 Energetic Neutrals Analyzer (CENA) sensor, the first and the only ever ENA sensor in a lunar orbit. CENA started its operation in the beginning of 2009. CENA can measure low energy ENAs, i.e. the energy below 3 keV. Using the dataset obtained from its 6-month operation, we discovered several populations of ENAs emitted from the Moon: begin{itemize} Backscattered ENAs of solar wind proton origin Backscattered ENAs of plasmasheet proton origin Sputtered hydrogen from the surface Indeed, backscattered ENAs had never expected as a major ENA population because the porosity (roughness) of the lunar surface is extremely high, and thus impinging plasma particles must have experienced several scattering to be absorbed. However, the observations clearly showed extremely high flux of backscattered ENAs. The discovery gave us a new insight in the field of low energy plasma interaction with porous surface in space. From the measured ENA flux and flying direction at the orbiter, we can derive the place of the ENA production and its flux at the lunar surface. They include information about solar wind plasma at the surface. One of the most attractive regions for investigation is a locally magnetized region (magnetic anomaly). Magnetic anomalies form mini-magnetospheres, which prevent the solar wind to precipitate. The efficiency of the protection influences directly the effectiveness of the space weathering by solar wind plasmas. Using the obtained CENA data, we could successfully image a reduction of the ENA flux inside known magnetic anomalies. The image clearly indicates the effective protection of the surface from the solar wind proton. Recently, we also developed a new method to obtain the electrostatic surface potential inside the anomaly from ENA observations. Improved ENA sensor will fly to Mercury by a Europe-Japan joint Mercury exploration, BepiColombo, as a part of Mercury Plasma Particle Experiment on board Mercury Magnetospheric Orbiter. The ENA experiment will image precipitating plasma at the surface of Mercury. Field-aligned potential in the precipitating regions is also to be derived. European Jupiter mission, JUpiter ICy moons Explorer (JUICE), will also equip an ENA sensor. ENA environment of the icy moons will be addressed as well.

Futaana, Yoshifumi; Barabash, Stas; Wieser, Martin; Bhardwaj, Anil; Wurz, Peter

390

High energy density physics experiments with intense heavy ion beams  

NASA Astrophysics Data System (ADS)

The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-1 accelerator. The NDCX-II accelerator planned for the 2010 time frame is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have developed a WDM target chamber, a cone focusing element to concentrate ion beam energy deposition on target, and a suite of target diagnostics including a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments for 2008 will explore target parameters such as temperature and electrical conductivity.

Bieniosek, Frank

2008-04-01

391

Wide angle reflections in OBC seismic physical model experiment  

NASA Astrophysics Data System (ADS)

Wide angle acquisition has been taken as a significant measure to obtain high quality seismic data and is getting greater attention. In this paper, we discuss ocean bottom cable (OBC) seismic wide angle reflections on the basis of a layered model experiment. Some experiment results don't support theoretical conclusions. The main experimental conclusions are: 1. Wide angle reflection energies are stronger than non-wide-angle reflections (up to twice as strong) but there is a big difference between observations and theoretical calculations that suggest the wide angle reflection energies are 15 times the nonwide-angle reflection energy. The reflection energy increases gradually rather than sharply as the theoretical calculations suggest. 2. The reflection events remain hyperbolic when the offset increases. 3. Wide angle reflection dominant frequency is about 20-30% less than nonwide-angle reflections and decreases as the offset increases. The non-wide-angle reflection dominant frequency shows no obvious variation for small offsets. 4. There is no wave shape mutation or polarity reversal near the critical angle. 5. The reflection event group features are the same for both cases of incidence angle greater and less than the critical angle. 6. Direct arrivals, multiples, and water bottom refractions influence the wide angle reflections of the sea floor.

Yang, Zheng-Hua; Huang, Yi-Jian; Wu, Yong-Xin

2012-06-01

392

Cold-Atom Physics Using Ultrathin Optical Fibers: Light-Induced Dipole Forces and Surface Interactions  

SciTech Connect

The strong evanescent field around ultrathin unclad optical fibers bears a high potential for detecting, trapping, and manipulating cold atoms. Introducing such a fiber into a cold-atom cloud, we investigate the interaction of a small number of cold cesium atoms with the guided fiber mode and with the fiber surface. Using high resolution spectroscopy, we observe and analyze light-induced dipole forces, van der Waals interaction, and a significant enhancement of the spontaneous emission rate of the atoms. The latter can be assigned to the modification of the vacuum modes by the fiber.

Sague, G.; Vetsch, E.; Alt, W.; Meschede, D.; Rauschenbeutel, A. [Institut fuer Angewandte Physik, Universitaet Bonn, Wegelerstr. 8, 53115 Bonn (Germany)

2007-10-19

393

The physical mechanism of comet outbursts: An experiment  

NASA Technical Reports Server (NTRS)

During a series of impact experiments into regolith-like powders at the NASA Ames Research Center Vertical Gun Facility in 1976, I observed and filmed a unique anomalous event that may illuminate outburst mechanisms in comets. During one test, a new batch of basalt powder (half the mass in particles less than 800 microns in diameter) retained some air pressure while the vacuum chamber was being evacuated. As a result, the projectile impacted into gas-charged regolith. Instead of ejecting the normal, relatively negligible amount of debris, the disturbance triggered a major eruption that lasted at least 18 seconds. The experimental results have been recently re-analyzed with reference to cometary phenomena. A series of frames from this eruption experiment are shown. The ejecta velocities of 150 to 300 cm/s would have been sufficient to drive debris into the coma of a comet nucleus smaller than a few kilometers diameter. The event suggests a mechanism for comet outbursts, discussed briefly by Hartmann et al.: the pore space in a layer of regolith, possibly with weak effective tensile strength, becomes gas charged as ice slowly sublimates. Once the effective tensile strength is exceeded by the gas pressure, the surface fails locally, triggering an eruption such as photographed here. This model is consistent with the emerging view of regolith materials on comets and is closest to the recent model of Rickman et al. The earlier models generally picture a more uniform flow of debris off the comet, not outbursts. Rickman et al. allow gas pressure to build until it matches the overburden pressure, followed by 'instantaneous blow-off'. They note that as soon as the mantle is found to be unstable, we consider it to be instantaneously swept away by the gas pressure. The main new points made here are that the experiment gives a more realistic view of the blow-off process after surface failure occurs, and the present model gives a recharge mechanism that can explain recurrent outbursts on comets such as P/Schwassmann-Wachmann 1 and 2060 Chiron. In fact, the resulting jets resemble distinct jet structures in high-resolution comet comae.

Hartmann, William K.

1993-01-01

394

Alkali vapor pressure modulation on the 100 ms scale in a single-cell vacuum system for cold atom experiments  

NASA Astrophysics Data System (ADS)

We describe and characterize a device for alkali vapor pressure modulation on the 100 ms timescale in a single-cell cold atom experiment. Its mechanism is based on optimized heat conduction between a current-modulated alkali dispenser and a heat sink at room temperature. We have studied both the short-term behavior during individual pulses and the long-term pressure evolution in the cell. The device combines fast trap loading and relatively long trap lifetime, enabling high repetition rates in a very simple setup. These features make it particularly suitable for portable atomic sensors.

Dugrain, Vincent; Rosenbusch, Peter; Reichel, Jakob

2014-08-01

395

Alkali vapor pressure modulation on the 100 ms scale in a single-cell vacuum system for cold atom experiments.  

PubMed

We describe and characterize a device for alkali vapor pressure modulation on the 100 ms timescale in a single-cell cold atom experiment. Its mechanism is based on optimized heat conduction between a current-modulated alkali dispenser and a heat sink at room temperature. We have studied both the short-term behavior during individual pulses and the long-term pressure evolution in the cell. The device combines fast trap loading and relatively long trap lifetime, enabling high repetition rates in a very simple setup. These features make it particularly suitable for portable atomic sensors. PMID:25173251

Dugrain, Vincent; Rosenbusch, Peter; Reichel, Jakob

2014-08-01

396

Assessing the engagement, learning, and overall experience of students operating an atomic absorption spectrophotometer with remote access technology.  

PubMed

The use of internet-based technologies in the teaching of laboratories has emerged as a promising education tool. This study evaluated the effectiveness of using remote access technology to operate an atomic absorption spectrophotometer in analyzing the iron content in a crude myoglobin extract. Sixty-two students were surveyed on their level of engagement, learning, and overall experience. Feedback from students suggests that the use of remote access technology is effective in teaching students the principles of chemical analysis by atomic absorption spectroscopy. © 2014 by The International Union of Biochemistry and Molecular Biology, 2014. PMID:25395308

Erasmus, Daniel J; Brewer, Sharon E; Cinel, Bruno

2014-11-14

397

Experiences Teaching Inquiry-Based Physics to Prospective Elementary School Teachers  

NASA Astrophysics Data System (ADS)

I will discuss my experience in teaching a laboratory-based introduction to physics intended for students in the elementary teacher education program at Mesa State College. This course was taught for three years and used the textbook and curriculum ``Physics by Inquiry'' developed by the Physics Education Group at the University of Washington. In this class students spend most of their time working on exercises and doing experiments, while the teacher circulates and engages students in discussions of their work. In addition to giving an overview of the curriculum I will talk about some of the successes, pitfalls, and difficulties in teaching such a course.

Tiernan, Bill

2006-10-01

398

Effects of Experimenting with Physical and Virtual Manipulatives on Students' Conceptual Understanding in Heat and Temperature  

ERIC Educational Resources Information Center

This study aimed to investigate the comparative value of experimenting with physical manipulatives (PM) in a sequential combination with virtual manipulatives (VM), with the use of PM preceding the use of VM, and of experimenting with PM alone, with respect to changes in students' conceptual understanding in the domain of heat and temperature. A…

Zacharia, Zacharias C.; Olympiou, Georgios; Papaevripidou, Marios

2008-01-01

399

PHYSICS OF FLUIDS 26, 026602 (2014) Beta-plane turbulence: Experiments with altimetry  

E-print Network

are measured by the Altimetric Imaging Velocimetry. The turbulent flows observed in the experiments developPHYSICS OF FLUIDS 26, 026602 (2014) Beta-plane turbulence: Experiments with altimetry Y. Zhang turbulent flows generated in a rotating tank with topographic -effect are presented. The velocity fields

Afanassiev, Iakov

400

Dissociable substrates for body motion and physical experience in the human action  

E-print Network

Dissociable substrates for body motion and physical experience in the human action observation with a human present, regardless of training experience. Conversely, the right ventral premotor cortex responds temporal sulcus Abstract Observation of human actions recruits a well-defined network of brain regions, yet

Hamilton, Antonia

401

Lysozyme Thermal Denaturation and Self-Interaction: Four Integrated Thermodynamic Experiments for the Physical Chemistry Laboratory  

ERIC Educational Resources Information Center

As part of an effort to infuse our physical chemistry laboratory with biologically relevant, investigative experiments, we detail four integrated thermodynamic experiments that characterize the denaturation (or unfolding) and self-interaction of hen egg white lysozyme as a function of pH and ionic strength. Students first use Protein Explorer to…

Schwinefus, Jeffrey J.; Schaefle, Nathaniel J.; Muth, Gregory W.; Miessler, Gary L.; Clark, Christopher A.

2008-01-01

402

Thermodynamic Exploration of Eosin-Lysozyme Binding: A Physical Chemistry and Biochemistry Laboratory Experiment  

ERIC Educational Resources Information Center

We developed a modular pair of experiments for use in the undergraduate physical chemistry and biochemistry laboratories. Both experiments examine the thermodynamics of the binding of a small molecule, eosin Y, to the protein lysozyme. The assay for binding is the quenching of lysozyme fluorescence by eosin through resonant energy transfer. In…

Huisman, Andrew J.; Hartsell, Lydia R.; Krueger, Brent P.; Pikaart, Michael J.

2010-01-01

403

Rich Experiences, Physical Activity Create Healthy Brains: An Interview with Developmental Psychologist William Greenough. Perspectives  

ERIC Educational Resources Information Center

In this interview, Council member William Greenough discusses the need for rich, complex experiences combined with physical activity in early childhood to help build a strong foundation for learning. He explains how rich, complex experiences are necessary for the development of sound brain architecture, particularly during early childhood, but…

Ray, Marcy, Ed.

2006-01-01

404

September 2013 A new particle physics experiment, planned to take place at Fermilab  

E-print Network

September 2013 A new particle physics experiment, planned to take place at Fermilab and the Sanford Lab, aims to transform our understanding of neutrinos and their role in the universe. Long has proposed to build a world-leading neutrino experiment that would involve construction at both

Quigg, Chris

405

Linear Dichroism of Cyanine Dyes in Stretched Polyvinyl Alcohol Films: A Physical Chemistry Laboratory Experiment.  

ERIC Educational Resources Information Center

Provides background information, procedures, and results of an undergraduate physical chemistry experiment on the polarization of absorption spectra of cyanine dyes in stretched polyvinyl alcohol films. The experiment gives a simple demonstration of the concept of linear dichromism and the validity of the TEM method used in the analyses. (JN)

Natarajan, L. V.; And Others

1983-01-01

406

Practical Ways Psychotherapy Can Support Physical Healthcare Experiences for Male Survivors of Childhood Sexual Abuse  

ERIC Educational Resources Information Center

Many survivors of child sexual abuse who engage in psychotherapy also experience physical health problems. This article summarizes the findings of a multiphased qualitative study about survivors' experiences in healthcare settings. The study informed the development of the "Handbook on Sensitive Practice for Health Care Practitioners: Lessons from…

Hovey, Angela; Stalker, Carol A.; Schachter, Candice L.; Teram, Eli; Lasiuk, Gerri

2011-01-01

407

Lived Employment Experiences of College Students and Graduates with Physical Disabilities in the United States  

ERIC Educational Resources Information Center

This phenomenological study aims at understanding lived experiences of college seniors and recent college graduates with physical disabilities seeking employment opportunities after graduation in the USA The extensive interviews revealed that participants' attitudes about and experiences with disability are diverse (pain to pride, denied…

Kim, Mikyong Minsun; Williams, Brenda C.

2012-01-01

408

2004 Rahman Prize in Computational Physics: HOW DO SOLIDS FAIL? A Research Adventure Using Lots Of Atoms And Big Computers  

NASA Astrophysics Data System (ADS)

During the last decade, I have been simulating the dynamic failure of brittle and ductile solids at the atomic level using millions of atoms and some of the world's fastest computers. Computer experiments encompassing crack dynamics in brittle fracture, crack blunting in ductile failure, and dislocation entanglement in work-hardening are some examples and have given new and exciting insights into the failure processes of solids. My goal is to give the audience an appreciation for the power of atomistic simulations, coupled with visualization, in studying "how solids fail."

Abraham, Farid

2004-03-01

409

Electronic interaction anisotropy between open-shell lanthanide atoms and helium from cold collision experiment  

E-print Network

Electronic interaction anisotropy between open-shell lanthanide atoms and helium from cold and helium is extremely small. The interaction of the rare-earth atoms with He gives rise to several shells submerged under the filled 6s electronic orbitals, resulting in large electronic spin and orbital

Krems, Roman

410

Guide for Atomic and Particle Physicists to CODATA’s Recommended Values of the Fundamental Physical Constants  

Microsoft Academic Search

The CODATA recommended values of the fundamental constants are\\u000a widely applied in particle, nuclear and atomic physics. They are a result of a complicated evaluation (adjustment) of numerous\\u000a correlated data of different natures. Their application is often rather mechanical and as a result is not free of various\\u000a confusions which are discussed in this note.

S. G. Karshenboim; D. I. Mendeleev

411

Savely G. Karshenboim: Guide for Atomic and Particle Physicists to CODATA’s Recommended Values of the Fundamental Physical Constants  

Microsoft Academic Search

The CODATA recommended values of the fundamental constants are widely applied\\u000ain particle, nuclear and atomic physics. They are a result of a complicated\\u000aevaluation (adjustment) of numerous correlated data of different nature. Their\\u000aapplication is often rather mechanical and as a result is not free of various\\u000aconfusions which are discussed in this note.

Savely G. Karshenboim; D. I. Mendeleev

412

Microscope-Based Fluid Physics Experiments in the Fluids and Combustion Facility on ISS  

NASA Technical Reports Server (NTRS)

At the NASA Glenn Research Center, the Microgravity Science Program is planning to conduct a large number of experiments on the International Space Station in both the Fluid Physics and Combustion Science disciplines, and is developing flight experiment hardware for use within the International Space Station's Fluids and Combustion Facility. Four fluids physics experiments that require an optical microscope will be sequentially conducted within a subrack payload to the Fluids Integrated Rack of the Fluids and Combustion Facility called the Light Microscopy Module, which will provide the containment, changeout, and diagnostic capabilities to perform the experiments. The Light Microscopy Module is planned as a fully remotely controllable on-orbit microscope facility, allowing flexible scheduling and control of experiments within International Space Station resources. This paper will focus on the four microscope-based experiments, specifically, their objectives and the sample cell and instrument hardware to accommodate their requirements.

Doherty, Michael P.; Motil, Susan M.; Snead, John H.; Malarik, Diane C.

2000-01-01

413

New Journal of Physics An ellipsoidal mirror for focusing of neutral atomic and  

E-print Network

-neutral, ground-state particles with very weak polarizability and no spin, such as ground-state helium-4 and neutral atom microscopy. The manipulation of charge-neutral beams of limited polarisability, spin time and we demonstrate focusing of a beam of neutral, ground state helium atoms down

Boyer, Edmond

414

Atoms and Molecules. Physical Science in Action[TM]. Schlessinger Science Library. [Videotape].  

ERIC Educational Resources Information Center

There are more than 20 million known substances in the universe, and they are all made of the same basic ingredients--atoms and molecules. In this fun and engaging program, kids will learn about the three main subatomic particles--protons, neutrons and electrons--as well as the forces that keep atoms and molecules together. They'll discover how…

2000

415

Physical Construction of the Chemical Atom: Is It Convenient to Go All the Way Back?  

ERIC Educational Resources Information Center

In this paper we present an analysis of chemistry texts (mainly textbooks) published during the first half of the 20th century. We show the evolution of the explanations therein in terms of atoms and of atomic structure, when scientists were interpreting phenomena as evidence of the discontinuous, corpuscular structure of matter. In this process…

Izquierdo-Aymerich, Merce; Aduriz-Bravo, Agustin

2009-01-01

416

High-energy-density physics experiments with intense heavy ion beams  

NASA Astrophysics Data System (ADS)

In this paper we discuss physical and technical issues of high-energy-density physics (HEDP) experiments with intense heavy ion beams that are being performed at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt. Special attention is given to a comparison of some recent results on expansion dynamics of evaporating lead that have been obtained in heavy ion beam driven HIHEX (Heavy-Ion Heating and Expansion) experiments at GSI-Darmstadt and in high-explosive driven shock wave loading and release experiments at IPCP-Chernogolovka.

Varentsov, D.; Ternovoi, V. Ya.; Kulish, M.; Fernengel, D.; Fertman, A.; Hug, A.; Menzel, J.; Ni, P.; Nikolaev, D. N.; Shilkin, N.; Turtikov, V.; Udrea, S.; Fortov, V. E.; Golubev, A. A.; Gryaznov, V. K.; Hoffmann, D. H. H.; Kim, V.; Lomonosov, I. V.; Mintsev, V.; Sharkov, B. Yu.; Shutov, A.; Spiller, P.; Tahir, N. A.; Wahl, H.

2007-07-01

417

Emulating Solid-State Physics with a Hybrid System of Ultracold Ions and Atoms  

NASA Astrophysics Data System (ADS)

We propose and theoretically investigate a hybrid system composed of a crystal of trapped ions coupled to a cloud of ultracold fermions. The ions form a periodic lattice and induce a band structure in the atoms. This system combines the advantages of high fidelity operations and detection offered by trapped ion systems with ultracold atomic systems. It also features close analogies to natural solid-state systems, as the atomic degrees of freedom couple to phonons of the ion lattice, thereby emulating a solid-state system. Starting from the microscopic many-body Hamiltonian, we derive the low energy Hamiltonian, including the atomic band structure, and give an expression for the atom-phonon coupling. We discuss possible experimental implementations such as a Peierls-like transition into a period-doubled dimerized state.

Bissbort, U.; Cocks, D.; Negretti, A.; Idziaszek, Z.; Calarco, T.; Schmidt-Kaler, F.; Hofstetter, W.; Gerritsma, R.

2013-08-01

418

Active experiments using rocket-borne shaped charge barium releases. [solar-terrestrial magnetospheric physics  

NASA Technical Reports Server (NTRS)

A reliable payload system and scaled down shaped charges were developed for carrying out experiments in solar-terrestrial magnetospheric physics. Four Nike-Tomahawk flights with apogees near 450 km were conducted to investigate magnetospheric electric fields, and two Taurus-Tomahawk rockets were flown in experiments on the auroral acceleration process in discrete auroras. In addition, a radial shaped charge was designed for plasma perturbation experiments.

Wescott, E. M.; Davis, T. N.

1980-01-01

419

The 2010 Interim Report of the Long-Baseline Neutrino Experiment Collaboration Physics Working Groups  

Microsoft Academic Search

In early 2010, the Long-Baseline Neutrino Experiment (LBNE) science collaboration initiated a study to investigate the physics potential of the experiment with a broad set of different beam, near- and far-detector configurations. Nine initial topics were identified as scientific areas that motivate construction of a long-baseline neutrino experiment with a very large far detector. We summarize the scientific justification for

T. Akiri; D. Allspach; M. Andrews; K. Arisaka; E. Arrieta-Diaz; M. Artuso; X. Bai; B. Balantekin; B. Baller; W. Barletta; G. Barr; M. Bass; A. Beck; B. Becker; V. Bellini; O. Benhar; B. Berger; M. Bergevin; E. Berman; H. Berns; A. Bernstein; F. Beroz; V. Bhatnagar; B. Bhuyan; R. Bionta; M. Bishai; A. Blake; E. Blaufuss; B. Bleakley; E. Blucher; S. Blusk; D. Boehnlein; T. Bolton; J. Brack; R. Bradford; R. Breedon; C. Bromberg; R. Brown; N. Buchanan; L. Camilleri; M. Campbell; R. Carr; G. Carminati; A. Chen; H. Chen; D. Cherdack; C. Chi; S. Childress; B. Choudhary; E. Church; D. Cline; S. Coleman; R. Corey; M. D'Agostino; G. Davies; S. Dazeley; J. De Jong; B. DeMaat; D. Demuth; A. Dighe; Z. Djurcic; J. Dolph; G. Drake; A. Drozhdin; H. Duan; H. Duyang; S. Dye; T. Dykhuis; D. Edmunds; S. Elliott; S. Enomoto; C. Escobar; J. Felde; F. Feyzi; B. Fleming; J. Fowler; W. Fox; A. Friedland; B. Fujikawa; H. Gallagher; G. Garilli; G. Garvey; V. Gehman; G. Geronimo; R. Gill; M. Goodman; J. Goon; D. Gorbunov; R. Gran; V. Guarino; E. Guarnaccia; R. Guenette; P. Gupta; A. Habig; R. Hackenberg; A. Hahn; R. Hahn; T. Haines; S. Hans; J. Harton; S. Hays; E. Hazen; Q. He; A. Heavey; K. Heeger; R. Hellauer; A. Himmel; G. Horton-Smith; J. Howell; P. Huber; P. Hurh; J. Huston; J. Hylen; J. Insler; D. Jaffe; C. James; C. Johnson; M. Johnson; R. Johnson; W. Johnson; W. Johnston; J. Johnstone; B. Jones; H. Jostlein; T. Junk; S. Junnarkar; R. Kadel; T. Kafka; D. Kaminski; G. Karagiorgi; A. Karle; J. Kaspar; T. Katori; B. Kayser; E. Kearns; S. Kettell; F. Khanam; J. Klein; J. Kneller; G. Koizumi; J. Kopp; S. Kopp; W. Kropp; V. Kudryavtsev; A. Kumar; J. Kumar; T. Kutter; T. Lackowski; K. Lande; K. Lang; F. Lanni; R. Lanza; T. Latorre; J. Learned; D. Lee; K. Lee; Y. Li; S. Linden; J. Ling; J. Link; L. Littenberg; L. Loiacono; T. Liu; J. Losecco; W. Louis; P. Lucas; C. Lunardini; B. Lundberg; T. Lundin; D. Makowiecki; S. Malys; S. Mandal; A. Mann; P. Mantsch; W. Marciano; C. Mariani; J. Maricic; A. Marino; M. Marshak; R. Maruyama; J. Mathews; S. Matsuno; C. Mauger; E. McCluskey; K. McDonald; K. McFarland; R. McKeown; R. McTaggart; R. Mehdiyev; W. Melnitchouk; Y. Meng; B. Mercurio; M. Messier; W. Metcalf; R. Milincic; W. Miller; G. Mills; S. Mishra; S. MoedSher; D. Mohapatra; N. Mokhov; C. Moore; J. Morfin; W. Morse; A. Moss; S. Mufson; J. Musser; D. Naples; J. Napolitano; M. Newcomer; B. Norris; S. Ouedraogo; B. Page; S. Pakvasa; J. Paley; V. Paolone; V. Papadimitriou; Z. Parsa; K. Partyka; Z. Pavlovic; C. Pearson; S. Perasso; R. Petti; R. Plunkett; C. Polly; S. Pordes; R. Potenza; A. Prakash; O. Prokofiev; X. Qian; J. Raaf; V. Radeka; R. Raghavan; R. Rameika; B. Rebel; S. Rescia; D. Reitzner; M. Richardson; K. Riesselman; M. Robinson; M. Rosen; C. Rosenfeld; R. Rucinski; T. Russo; S. Sahijpal; S. Salon; N. Samios; M. Sanchez; R. Schmitt; D. Schmitz; J. Schneps; K. Scholberg; S. Seibert; F. Sergiampietri; M. Shaevitz; P. Shanahan; M. Shaposhnikov; R. Sharma; N. Simos; V. Singh; G. Sinnis; W. Sippach; T. Skwarnicki; M. Smy; H. Sobel; M. Soderberg; J. Sondericker; W. Sondheim; J. Spitz; N. Spooner; M. Stancari; I. Stancu; J. Stewart; P. Stoler; J. Stone; S. Stone; J. Strait; T. Straszheim; S. Striganov; G. Sullivan; R. Svoboda; B. Szczerbinska; A. Szelc; R. Talaga; H. Tanaka; R. Tayloe; D. Taylor; J. Thomas; L. Thompson; M. Thomson; C. Thorn; X. Tian; W. Toki; N. Tolich; M. Tripathi; M. Trovato; H. Tseung; M. Tzanov; J. Urheim; S. Usman; M. Vagins; R. Van Berg; R. Van de Water; G. Varner; K. Vaziri; G. Velev; B. Viren; T. Wachala; C. Walter; H. Wang; Z. Wang; D. Warner; D. Webber; A. Weber; R. Wendell; C. Wendt; M. Wetstein; H. White; S. White; L. Whitehead; W. Willis; R. J. Wilson; L. Winslow; J. Ye; M. Yeh; B. Yu; G. Zeller; C. Zhang; E. Zimmerman; R. Zwaska

2011-01-01

420

Energetic Particle Physics In Fusion Research In Preparation For Burning Plasma Experiments  

SciTech Connect

The area of energetic particle (EP) physics of fusion research has been actively and extensively researched in recent decades. The progress achieved in advancing and understanding EP physics has been substantial since the last comprehensive review on this topic by W.W. Heidbrink and G.J. Sadler [1]. That review coincided with the start of deuterium-tritium (DT) experiments on Tokamak Fusion Test reactor (TFTR) and full scale fusion alphas physics studies. Fusion research in recent years has been influenced by EP physics in many ways including the limitations imposed by the "sea" of Alfven eigenmodes (AE) in particular by the toroidicityinduced AEs (TAE) modes and reversed shear Alfven (RSAE). In present paper we attempt a broad review of EP physics progress in tokamaks and spherical tori since the first DT experiments on TFTR and JET (Joint European Torus) including helical/stellarator devices. Introductory discussions on basic ingredients of EP physics, i.e. particle orbits in STs, fundamental diagnostic techniques of EPs and instabilities, wave particle resonances and others are given to help understanding the advanced topics of EP physics. At the end we cover important and interesting physics issues toward the burning plasma experiments such as ITER (International Thermonuclear Experimental Reactor).

Gorelenkov, Nikolai N [PPPL

2013-06-01

421

What do students learn about work in physical and virtual experiments with inclined planes?  

NSDL National Science Digital Library

In previous studies, we have reported a difference in how physical and virtual manipulatives support students' understanding of the physics definition of work in the context of simple machines. We have shown that students who use the virtual manipulative (a computer simulation) before performing a physical experiment provided the correct response to multiple-choice questions about work more frequently than students who first use the physical manipulative. In this paper, we further analyze students' responses to a series of questions about work in the context of inclined planes to explore the models students used to answer the questions. While we had anticipated that students who performed the physical experiment would incorrectly respond to the multiple-choice questions in accordance with their observations (i.e. a longer ramp requires more work due to frictional effects), we actually observed these students more frequently using an alternate model that a longer ramp requires less work.

Chini, Jacquelyn J.; Madsen, Adrian M.; Rebello, N. S.; Puntambekar, Sadhana

2012-05-15

422

Physics of Polymersomes: lateral segregation experiments and raft simulations  

NASA Astrophysics Data System (ADS)

Coupling between the inner and outer leaflets of a bilayer plays an important role in biomembrane function, particularly in inducing and registering rafts across leaflets for various cellular signals. However, mechanisms of raft registration remain elusive and several alternatives have been proposed, ranging from electrostatic coupling to chain interdigitation. A general mechanism has been suggested by recent experiments on Polymersomes in which binary mixtures of diblock copolymer amphiphiles exhibit domain registration upon ligand-induced segregation. Using coarse grained molecular dynamics (CGMD) simulations rooted in atomistics, raft registration arises spontaneously in bilayers with a calcium- or ligand-crosslinked ordered phase segregating from a liquid disordered phase. When rafts are not registered, a thickness mismatch between phases induces a ``bump'' in the apposing liquid phase leaflet, and the associated localized curvature guides rafts together stabilizing the registered state. The absence of explicit charge in the model and the fact that domain size modulates transmembrane coupling demonstrate that collective interactions are sufficient for raft registration. References: (1) D.A. Christian, et al. Spotted vesicles, striped micelles, and Janus assemblies induced by ligand binding. Nature Materials 8: 843--849 (2009). (2) D. Pantano, P.B. Moore, M.L. Klein, D.E. Discher. Raft registration across bilayers in a molecularly detailed model. Soft Matter 7, 8182-8191 (2011).

Discher, Dennis

2012-02-01

423

Results on axion physics from the CAST Experiment at CERN  

E-print Network

Axions are expected to be produced in the sun via the Primakoff process. They may be detected through the inverse process in the laboratory, under the influence of a strong magnetic field, giving rise to X-rays of energies in the range of a few keV. Such an Axion detector is the CERN Axion Solar Telescope (CAST), collecting data since 2003. Results have been published, pushing the axion-photon coupling g$_{a\\gamma}$ below the 10$^{-10}$ GeV$^{-1}$ limit at 95% CL, for axion masses less than 0.02 eV. This limit is nearly an order of magnitude lower than previous experimental limits and surpassed for the first time limits set from astrophysical arguments based on the energy-loss concept. The experiment is currently exploring axion masses in the range of 0.02 eV $< m_a <$ 1.1 eV. In the next run, currently under preparation, the axion mass explored will be extended up to the limit of 1.1 eV, testing for the first time the region of theoretical axion models with the axion helioscope method.

Christos Eleftheriadis

2007-06-05

424

Modern physics lab experiments using crystal X-ray generators  

SciTech Connect

Crystal X-ray generators can be made using small pyroelectric crystals such as LiTaO{sub 3} surrounded by gas at pressures of typically 15 mT. When heat is applied to one surface a strong electric field is produced at the opposite side of the crystal and electrons are accelerated toward it, giving rise to Ta L and M x-rays. On cooling the direction of the electric field reverses and a target x-ray spectrum is obtained. Two x-ray generators are described: The first is a sealed battery-powered, portable device, which can be used in routine lab experiments, such as the study of characteristic x-rays, x-ray absorption edges and x-ray fluorescence. The second is more sophisticated and is used for more advanced students. The object is to gain a better understanding of crystal x-ray generators by varying parameters such as the temperature range through which the crystal is cycled or the gas pressure or gas-type or the crystal to target distance. For both generators the decay time of the x-ray intensity can be studied as well as the x-ray spectra.

Shafroth, S. M. [Physics and Astronomy Department, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3255 (United States); Brownridge, J. D. [Department of Physics, Applied Physics and Astronomy, State University of New York at Binghamton, Binghamton, New York 13901 (United States)

1999-06-10

425

Physics at FAIR  

NASA Astrophysics Data System (ADS)

The Facility for Antiproton and Ion Research (FAIR) is under construction at Darmstadt, Germany. It will deliver high intensity beams of ions and antiprotons for experiments in the fields of atomic physics, plasma physics, nuclear physics, hadron physics, nuclear matter physics, material physics and biophysics. One of the scientific pillars of FAIR is the Compressed Baryonic Matter (CBM) experiment which is designed for the study of high density nuclear matter as it exists in the core of neutron stars. In this article the scientific program of FAIR will be reviewed with emphasis on the CBM experiment.

Chattopadhyay, Subhasis

2014-11-01

426

Insights from laboratory experiments into the physics of pyroclastic flows  

NASA Astrophysics Data System (ADS)

We studied the transport and sedimentation behavior of rapid shear flows of gas-fluidized volcanic ash in a laboratory flume in order to better understand the kinematics of pyroclastic flows. The work was based on a previous study in which we explored the fluidization and settling behaviour of ash under quasi-static conditions in a 1-D high-temperature fluidization rig. Provided that temperature is high enough (>150 °C) to significantly reduce cohesion, ash fractions of pyroclastic flow deposits fluidize in the manner of Geldart group-A powders, with large expansions in the non-bubbling regime. When the flux of fluidizing gas is removed, the ash re-sediments by hindered settling at rates which, for a given material, are independent of temperature up to 550 °C. Armed with this knowledge, we built a 3-m-long lock-exchange flume in which we generated horizontal flows of fluidized ash. The ash was first placed in the flume reservoir, heated to 180 °C and expanded by gas flow up to 45 % above loose packing. It was then released down the flume and allowed to defluidize freely. The resulting flows were filmed at high speed, and the films were then analyzed visually and using a particle-tracking algorithm. The flows were typically several cm thick, had frontal speeds of up to ~2 m s-1, and were non-turbulent on scales larger than the constituent particles. Since the settling behavior of quasi-static ash is temperature independent, we expect the same to be true for flowing ash. Deposition took place progressively during transport until the flow was entirely consumed and motion ceased. It commenced 5-20 cm rearward of the leading edge and (for a given expansion) proceeded at a rate independent of distance from the lock gate. Deposit aggradation velocities were equal to those inferred beneath quasi-static bed collapse tests of the same ash at the same initial expansions, showing that shear rates of up to ~300 s-1 have no measurable effect on aggradation rate. Initially non-expanded (but just fluidized) ash deposited progressively at a rate indicative of an expansion of a few percent, perhaps due to Reynolds dilation during initial slumping. These behaviors have subsequently been confirmed by similar experiments using industrial group-A cracking catalyst powders instead of ash, and the combined results collapse to reveal a very simple scaling for the runout durations of the flows. Velocity profiles in the ash flows reveal that the frontal regions slid across the flume floor on very thin basal shear layers, implying high basal stresses, but that once sedimentation commenced, a no-slip condition was established at the depositional interface. The experiments show that even cm-thin, non-turbulent and poorly expanded flows of ash deposit progressively, as inferred for many pyroclastic flows. This raises the possibility that deposit aggradation rates in mathematical models of dense pyroclastic flows could be parameterized using values measured using 1D rigs. High frontal stresses are consistent with the occurrence of scour surfaces at the bases of some pyroclastic flow deposits.

Girolami, L.; Druitt, T. H.; Roche, O.

2009-12-01

427

Atomic-scale wear of amorphous hydrogenated carbon during intermittent contact: a combined study using experiment, simulation, and theory.  

PubMed

In this study, we explore the wear behavior of amplitude modulation atomic force microscopy (AM-AFM, an intermittent-contact AFM mode) tips coated with a common type of diamond-like carbon, amorphous hydrogenated carbon (a-C:H), when scanned against an ultra-nanocrystalline diamond (UNCD) sample both experimentally and through molecular dynamics (MD) simulations. Finite element analysis is utilized in a unique way to create a representative geometry of the tip to be simulated in MD. To conduct consistent and quantitative experiments, we apply a protocol that involves determining the tip-sample interaction geometry, calculating the tip-sample force and normal contact stress over the course of the wear test, and precisely quantifying the wear volume using high-resolution transmission electron microscopy imaging. The results reveal gradual wear of a-C:H with no sign of fracture or plastic deformation. The wear rate of a-C:H is consistent with a reaction-rate-based wear theory, which predicts an exponential dependence of the rate of atom removal on the average normal contact stress. From this, kinetic parameters governing the wear process are estimated. MD simulations of an a-C:H tip, whose radius is comparable to the tip radii used in experiments, making contact with a UNCD sample multiple times exhibit an atomic-level removal process. The atomistic wear events observed in the simulations are correlated with under-coordinated atomic species at the contacting surfaces. PMID:24922087

Vahdat, Vahid; Ryan, Kathleen E; Keating, Pamela L; Jiang, Yijie; Adiga, Shashishekar P; Schall, J David; Turner, Kevin T; Harrison, Judith A; Carpick, Robert W

2014-07-22

428

A Space Experiment to Measure the Atomic Oxygen Erosion of Polymers and Demonstrate a Technique to Identify Sources of Silicone Contamination  

NASA Technical Reports Server (NTRS)

A low Earth orbital space experiment entitled, "Polymers Erosion And Contamination Experiment", (PEACE) has been designed as a Get-Away Special (GAS Can) experiment to be accommodated as a Shuttle in-bay environmental exposure experiment. The first objective is to measure the atomic oxygen erosion yields of approximately 40 different polymeric materials by mass loss and erosion measurements using atomic force microscopy. The second objective is to evaluate the capability of identifying sources of silicone contamination through the use of a pin-hole contamination camera which utilizes environmental atomic oxygen to produce a contaminant source image on an optical substrate.

Banks, Bruce A.; deGroh, Kim K.; Baney-Barton, Elyse; Sechkar, Edward A.; Hunt, Patricia K.; Willoughby, Alan; Bemer, Meagan; Hope, Stephanie; Koo, Julie; Kaminski, Carolyn; Youngstrom, Erica

1999-01-01

429

Experiments at the Triangle Universities Nuclear Laboratory for the undergraduate physics curriculum  

SciTech Connect

Experiments are being developed at the Triangle Universities Nuclear Laboratory to offer advanced undergraduate physics students laboratory experiences in the atmosphere of a frontier accelerator facility. These experiments differ from projects done by Undergraduate Research Assistants in that they are designed specifically for integration into the undergraduate curriculum as part of a structured laboratory course. The immediate goal of the program is to develop four accelerator-based experiments for use in the undergraduate Advanced Laboratory course at Duke University. Two newly developed experiments, {ital Carbon-Carbon Mott Scattering} and {ital Lifetime Measurements of an Auger Emitter}, will be described. In addition, the logistics of conducting undergraduate laboratory course work in an active research facility will be discussed. {copyright} {ital 1999 American Institute of Physics.}

Howell, C.R. [Department of Physics, Duke University and the Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 (United States)

1999-06-01

430

Many-Body Physics: Collective fermionic excitations in quark-gluon plasmas and cold atom systems  

E-print Network

In this talk I discuss collective excitations that carry fermion quantum numbers. Such excitations occur in the quark-gluon plasma and can also be produced in cold atom systems under special conditions.

Blaizot, Jean-Paul

2014-01-01

431

Many-Body Physics: Collective fermionic excitations in quark-gluon plasmas and cold atom systems  

E-print Network

In this talk I discuss collective excitations that carry fermion quantum numbers. Such excitations occur in the quark-gluon plasma and can also be produced in cold atom systems under special conditions.

Jean-Paul Blaizot

2014-05-13

432

Atomic Spectroscopy  

NSDL National Science Digital Library

This article outlines the main concepts of atomic structure, with some emphasis on terminology and notation. Topics of discussion include wavelengths, intensities, shapes of spectral lines, and LS coupling. Originally appearing in the Atomic, Molecular, and Optical Physics Handbook, edited by Drake, this online version of Atomic Spectroscopy contains internal links as well as external links to spectroscopic data.

Martin, William; Wiese, Wolfgang

2003-10-10

433

FROM THE HISTORY OF PHYSICS: L D Landau in the Soviet Atomic Project: a documentary study  

NASA Astrophysics Data System (ADS)

The article presents information about the participation of Academician L D Landau in the Soviet Atomic Project and is based on a study of archive documents of the First Main Directorate. Their analysis points to L D Landau's important contribution to the development of the theory of heterogeneous nuclear reactors and to the computational justification of the first designs of atomic and hydrogen bombs. Many of the quoted documents have never been published before.

Kiselev, G. V.

2008-09-01

434

Dense atom clouds in a holographic atom trap  

NASA Astrophysics Data System (ADS)

We demonstrate the production of high-density cold 87Rb samples (2 × 1014 atoms/cm3) in a simple optical lattice formed with YAG light that is diffracted from a holographic phase plate. A loading protocol is described that results in 10,000 atoms per 10 ?m × 10 ?m × 100 ?m unit cell of the lattice site. Rapid free evaporation leads to a temperature of 50 ?K and phase space densities of 1/150 within 50 ms. The resulting small, high-density atomic clouds are very attractive for a number of experiments, including ultracold Rydberg atom physics.

Newell, R.; Sebby, J.; Walker, T. G.

2003-07-01

435

Segregation Effects at Internal Interfaces in Alloys: Atom-Probe Tomographic Experiments and Simulations  

NASA Astrophysics Data System (ADS)

This talk first focuses on experimental studies of solute segregation effects on an atomic scale of solute segregation at grain boundaries (GBs) and heterophase interfaces employing atom-probe field-ion microscopy and three-dimensional atom-probe tomography; both instruments provide a spatial resolution of ca. 0.2 nm in direct space. It is demonstrated that the Gibbsian interfacial excess of solute at an internal interface depends on its five macroscopic degrees of freedom (DOFs), which is consistent with J. Cahn's local phase rules for GBs and heterophase interfaces. Experimental data is presented for GBs in metallic alloys (e.g. Fe-Si, Al-Sc-Mg, Ni-Al-Cr alloys), and metal silicide/silicon and indium arsenide heterophase interfaces. Secondly, atomic-scale simulations will be presented of GB segregation in binary metallic alloys described by embedded-atom method potentials employing Metropolis algorithm Monte Carlo simulations, which further demonstrate the intimate relationships between GB structure, on an atomic scale, and the Gibbsian interfacial excess of solute. It is also shown how the microscopic DOFs of a GB affect the Gibbsian interfacial excess of solute. Additionally, the results of atom-probe tomographic studies of segregation effects at heterophase interfaces between the gamma (f.c.c.) and gamma prime (L12 structure) heterophase interfaces in Ni-Al-Cr alloys are discussed and compared in detail with the results of lattice kinetic Monte Carlo (LKMC) simulations, which involves a vacancy mediated diffusion mechanism. The LKMC simulation allow us to explain the role of vacancy-solute binding energies on the observed concentration profiles of Ni, Al, and Cr between the gamma and gamma prime phases. These detailed experimental and simulation studies of segregation effects result in a relatively new atomistic picture of segregation at internal interfaces that differs from the conventional wisdoms found in the literature concerning segregation.

Seidman, David

2008-03-01

436

Current drive and current profile control studies in the Tokamak Physics Experiment (TPX)  

NASA Astrophysics Data System (ADS)

Simulation studies of noninductive current profile control have been carried out for the Tokamak Physics Experiment (TPX).1 The predicted MHD equilibria have been analyzed for ideal ballooning stability and stability to the low-n, external kink modes. An advanced rf physics technique for off-axis current profile control has also been investigated for TPX. This scheme utilizes mode conversion and electron absorption in a D-(3He) plasma mixture.

Bonoli, P. T.; Porkolab, M.; Sugiyama, L.; Kessel, C.

1996-02-01

437

Contribution of gallium experiments to the understanding of solar physics and neutrino physics  

SciTech Connect

The results of gallium measurements of solar neutrino and measurements with artificial sources of neutrinos are presented. Conclusions are drawn from these results, and the potential of the SAGE experiment for studying transitions of active neutrinos to sterile states for {Delta}m{sup 2} > 0.5 eV{sup 2} and a sensitivity of a few percent to the disappearance of electron neutrinos is examined.

Gavrin, V. N., E-mail: gavrin@inr.ru [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

2013-10-15

438

PHYSICAL REVIEW A 86, 053412 (2012) Fast compression of a cold atomic cloud using a blue-detuned crossed dipole trap  

E-print Network

PHYSICAL REVIEW A 86, 053412 (2012) Fast compression of a cold atomic cloud using a blue-detuned the experimental realization of a compressible blue-detuned crossed dipole trap for cold atoms allowing for fast consists of two intersecting tubes of blue-detuned laser light. These tubes are formed using a single

439

arXiv:physics/0604079v321Jan2007 Magnetic trapping of buffer-gas cooled chromium atoms and prospects for the  

E-print Network

arXiv:physics/0604079v321Jan2007 Magnetic trapping of buffer-gas cooled chromium atoms (Dated: January 23, 2007) We report the successful buffer-gas cooling and magnetic trapping of chromium chromium and eu- ropium [6, 7] as well as several other atoms [8]. Apart from the above mentioned

Peters, Achim

440

Striving to Be "in" the Profession and "of" It: The African American Experience in Physical Education and Kinesiology  

ERIC Educational Resources Information Center

This study analyzes the experiences of African Americans in the physical education and kinesiology profession since the late 1850s. Using a variety of primary and secondary source material, we place special emphasis on the experiences of African American physical educators in higher education and in the American Alliance for Health, Physical

Wiggins, David K.; Wiggins, Brenda P.

2011-01-01

441

Monochromatic radiography of high energy density physics experiments on the MAGPIE generatora)  

NASA Astrophysics Data System (ADS)

A monochromatic X-ray backlighter based on Bragg reflection from a spherically bent quartz crystal has been developed for the MAGPIE pulsed power generator at Imperial College (1.4 MA, 240 ns) [I. H. Mitchell et al., Rev. Sci. Instrum. 67, 1533 (2005)]. This instrument has been used to diagnose high energy density physics experiments with 1.865 keV radiation (Silicon He-?) from a laser plasma source driven by a ˜7 J, 1 ns pulse from the Cerberus laser. The design of the diagnostic, its characterisation and performance, and initial results in which the instrument was used to radiograph a shock physics experiment on MAGPIE are discussed.

Hall, G. N.; Burdiak, G. C.; Suttle, L.; Stuart, N. H.; Swadling, G. F.; Lebedev, S. V.; Smith, R. A.; Patankar, S.; Suzuki-Vidal, F.; de Grouchy, P.; Harvey-Thompson, A. J.; Bennett, M.; Bland, S. N.; Pickworth, L.; Skidmore, J.

2014-11-01

442

Observation of the Anderson metal-insulator transition with atomic matter waves: Theory and experiment  

SciTech Connect

Using a cold atomic gas exposed to laser pulses - a realization of the chaotic quasiperiodic kicked rotor with three incommensurate frequencies - we study experimentally and theoretically the Anderson metal-insulator transition in three dimensions. Sensitive measurements of the atomic wave function and the use of finite-size scaling techniques make it possible to unambiguously demonstrate the existence of a quantum phase transition and to measure its critical exponents. By taking proper account of systematic corrections to one-parameter scaling, we show the universality of the critical exponent {nu}=1.59{+-}0.01, which is found to be equal to the one previously computed for the Anderson model.

Lemarie, Gabriel; Delande, Dominique [Laboratoire Kastler Brossel, UPMC-Paris 6, ENS, CNRS, 4 Place Jussieu, F-75005 Paris (France); Chabe, Julien; Szriftgiser, Pascal; Garreau, Jean Claude [Laboratoire PhLAM, , Universite de Lille 1, CNRS, CERLA, F-59655 Villeneuve d'Ascq Cedex (France); Gremaud, Benoit [Laboratoire Kastler Brossel, UPMC-Paris 6, ENS, CNRS, 4 Place Jussieu, F-75005 Paris (France); Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore)

2009-10-15

443

Atomic, electronic and magnetic structure of graphene/iron and nickel interfaces: theory and experiment  

E-print Network

First-principles calculations of the effect of carbon coverage on the atomic, electronic and magnetic structure of nickel and iron substrates demonstrate insignificant changes in the interatomic distances and magnetic moments on the atoms of the metallic substrates. The coverage of the iron surface by mono- and few-layer graphene induces significant changes in the orbital occupancies and exchange interactions between the layers in contrast to the case of a nickel substrate for which changes in the orbital ordering and exchange interactions are much smaller. Experimental measurements demonstrate the presence of ferromagnetic fcc-iron in Fe@C nanoparticles and the superparamagnetic behavior of Ni@C nanoparticles.

Boukhvalov, D W; Uimin, M A; Korolev, A V; Yermakov, A Ye

2014-01-01

444

Nucleons, Nuclei, and Atoms 1.1 Overview  

E-print Network

1 Nucleons, Nuclei, and Atoms 1.1 Overview Despite the success of the Standard Model in explaining is the theme of this chapter: ultrasensitive techniques in atomic, nuclear, and particle physics that might of fundamental symmetries in experiments involving nucleons, nuclei, and atoms have played an essential role

445

Advantages and limitations of nuclear physics experiments at an ISIS-class spallation neutron source  

NASA Astrophysics Data System (ADS)

Nuclear physics experiments have a long history of being conducted on spallation neutron sources. Like other experiments, these measurements take advantage of the identification of the incident neutron energy by the time-of-flight (ToF) technique. However, in some ways these experiments are often in direct conflict with other experiments. Especially in large (ISIS or SNS class) facilities, the design of the source often reflects a compromise between different experimental needs and requirements. It has been a long standing question for nuclear physics experiments how limiting these compromises are and how they can be dealt with. We have therefore calculated the incident neutron energy spectrum, along with the gamma background spectrum, for flight path (FP) 5 at the Los Alamos Neutron Science Center (LANSCE) Manuel Lujan Jr. Neutron Scattering Center (Lujan Center) including a detailed evaluation of the signal shape. We will discuss the advantages and limitations of the nuclear physics experiments at FP-5 in the light of our results.

Mocko, M.; Muhrer, G.; Tovesson, F.

2008-05-01

446

EDITORIAL: The 20th European Sectional Conference on Atomic and Molecular Physics of Ionized Gases The 20th European Sectional Conference on Atomic and Molecular Physics of Ionized Gases  

NASA Astrophysics Data System (ADS)

This special issue consists of papers that are associated with invited lectures, workshop papers and hot topic papers presented at the 20th European Sectional Conference on Atomic and Molecular Physics of Ionized Gases (ESCAMPIG XX). This conference was organized in Novi Sad (Serbia) from 13 to 17 July 2010 by the Institute of Physics of the University of Belgrade. It is important to note that this is not a conference 'proceedings'. Following the initial selection process by the International Scientific Committee, all papers were submitted to the journal by the authors and have been fully peer reviewed to the standard required for publication in Plasma Sources Science and Technology (PSST). The papers are based on presentations given at the conference but are intended to be specialized technical papers covering all or part of the topic presented by the author during the meeting. The ESCAMPIG conference is a regular biennial Europhysics Conference of the European Physical Society focusing on collisional and radiative aspects of atomic and molecular physics in partially ionized gases as well as on plasma-surface interaction. The conference focuses on low-temperature plasma sciences in general and includes the following topics: Atomic and molecular processes in plasmas Transport phenomena, particle velocity distribution function Physical basis of plasma chemistry Plasma surface interaction (boundary layers, sheath, surface processes) Plasma diagnostics Plasma and discharges theory and simulation Self-organization in plasmas, dusty plasmas Upper atmospheric plasmas and space plasmas Low-pressure plasma sources High-pressure plasma sources Plasmas and gas flows Laser-produced plasmas During ESCAMPIG XX special sessions were dedicated to workshops on: Atomic and molecular collision data for plasma modeling, organized by Professors Z Lj Petrovic and N Mason Plasmas in medicine, organized by Dr N Puac and Professor G Fridman. The conference topics were represented in the program by 16 invited lectures, 7 selected hot topics, and 191 poster presentations. The largest number of contributed papers was submitted in Topic 5: Plasma diagnostics (37). The workshop topics were addressed by 10 invited lectures, 5 oral presentations and 7 posters. A post-conference workshop with 5 invited lectures was organized, dealing with the data needs for modeling of plasma sources of light. ESCAMPIG XX was attended by 185 scientists from 31 countries. Of the participants, 30% were PhD students (55). The list includes scientists from the USA, Japan, Australia, Mexico and other non-European countries, which indicates the truly international status of the conference. We would like to thank the authors for their efforts in preparing stimulating lectures and interesting articles for the readers of PSST, and the scientific community dealing with ionized gases, plasma sources and atomic, molecular and chemical physics of low-temperature plasmas for continued interest in the field of ESCAMPIG. We would like to thank the organizers of all previous ESCAMPIG conferences for setting the standards for organization and, in particular, the organizers of ESCAMPIG XVIII and XIX for their direct help and insight. Finally the International Scientific Committee and its chairman in particular have worked hard to select the best possible program and to keep us in line with almost 40 years of tradition and standards of the conference. Most importantly this has been the 20th conference. The quality of new papers shows maturity and new vistas in the field that has produced so much fundamental understanding of complex, non-equilibrium, even nonlinear plasmas. At the same time the field has led to some of the key technologies of modern civilization and has shown that responsible science that pays attention to its societal benefits should have no fear for its future. All critical issues studied today were presented at the meeting and only a small part is represented here. For example, discharges in liquids or above liquids were covered by several lectures represented by two pa

Petrovi?, Zoran Lj; Mari?, Dragana; Malovi?, Gordana

2011-03-01

447

Experiment to study the. beta. -decay of free atomic and molecular tritium. [For determining antineutrino mass  

SciTech Connect

An apparatus is described which will allow the measurement of the ..beta..-decay of free tritium atoms and molecules for determining antineutrino mass. It consists of an RF dissociator, a long cylindrical decay region open at both ends, a guide field, and a magnetic spectrometer.

Robertson, R.G.H.; Bowles, T.J.; Maley, M.; Browne, J.C.; Burritt, T.; Toevs, J.; Stelts, M.; Helfrick, J.; Knapp, D.; Ledebuhr, A.G.

1982-01-01

448

Atomic Oxygen Exposure of Power System and other Spacecraft Materials: Results of the EOIM-3 Experiment  

NASA Technical Reports Server (NTRS)

In order to test their reactivity with Atomic Oxygen, twenty five materials were flown on the EOIM-3 (Evaluation of Oxygen Interactions with Materials) portion of the STS-46 Mission. These materials include refractory metals, candidate insulation materials, candidate radiator coatings, and a selection of miscellaneous materials. This report documents the results of the pre- and post-flight analysis of these materials.

Morton, Thomas L.; Ferguson, Dale C.

1997-01-01

449

PHYSICAL REVIEW B 89, 094105 (2014) Atomic sublattice decomposition of piezoelectric response in tetragonal  

E-print Network

September 2013; published 21 March 2014) The piezoelectric properties of tetragonal perovskites PbTiO3, Ba materials show different behaviors at the atomic scale. In PbTiO3, the Pb and Ti contribute almost equally.094105 PACS number(s): 77.84.Lf, 71.15.-m, 71.20.-b I. INTRODUCTION Lead-based piezoelectric materials

Rappe, Andrew M.

450

Atomic physics with highly charged ions. Progress report, FY 1989--91  

SciTech Connect

This report discusses: One electron outer shell processes in fast ion-atom collisions; role of electron-electron interaction in two-electron processes; multi-electron processes at low energy; multi-electron processes at high energy; inner shell processes; molecular fragmentation studies; theory; and, JRM laboratory operations.

Richard, P.

1991-08-01

451

Progress and Prospects of Fermi Gas Physics in Cold Atom Traps  

NASA Astrophysics Data System (ADS)

The pursuit of fermion superfluidity in cold atom traps has been touted as a worthy successor to the celebrated quest for Bose–Einstein condensation. Presently, the field appears to be closing in on this new target. This manuscript reviews some of the exciting prospects, the obstacles on the way, and the progress in overcoming these hurdles.

Timmermans, Eddy

452

Atomic Force Microscopy Maps Nanomechanical Properties of Cells | Physical Sciences in Oncology  

Cancer.gov

Researchers at Purdue University and The University of Oxford have used an atomic force microscope to measure the dynamic mechanical properties of living cells. The investigators, led by Arvind Raman, believe this technology could be used to diagnose human disease and better understand a wide range of biological processes, such as how cells adhere to tissues or how cancer cells evolve during metastasis.

453

ATOMIC AND MOLECULAR PHYSICS: Static dipole polarizabilities of Scn (n <= 15) clusters  

Microsoft Academic Search

The static dipole polarizabilities of scandium clusters with up to 15 atoms are determined by using the numerically finite field method in the framework of density functional theory. The electronic effects on the polarizabilities are investigated for the scandium clusters. We examine a large highest occupied molecular orbital --- the lowest occupied molecular orbital (HOMO-LUMO) gap of a scandium cluster

Xi-Bo Li; Hong-Yan Wang; Jiang-Shan Luo; Yun-Dong Guo; Wei-Dong Wu; Yong-Jian Tang

2009-01-01

454

The problems of solar-terrestrial coupling and new processes introduced to the physics of the ionosphere from the physics of atomic collisions  

NASA Astrophysics Data System (ADS)

Further progress in research of solar-terrestrial coupling requires better understanding of solar variability influence on the ionosphere. The most powerful manifestations of solar variability are solar flares and geomagnetic storms. During a flare EUV/X-ray irradiations are completely absorbed in the ionosphere producing SID. During geomagnetic storms precipitations of electrons with energy of several keV (and to a lesser extent protons precipitations) from radiation belts and geomagnetosphere produce additional ionization and low latitude auroras. Considering the physics of ionosphere during the last several decades we have been taking into account three novel processes well known in the physics of atomic collisions. These are Auger effect [S. V. Avakyan, The consideration of Auger processes in the upper atmosphere of Earth. In Abstracts of paper presented at the Tenth scien. and techn. Conf. of young specialists of S.I. Vavilov State Optical Institute, 1974, 29-31.], multiple photoionization of upper, valence shell [S.V. Avakyan, The source of O++ ions in the upper atmosphere, 1979, Cosmic Res, 17, 942 - 943] and Rydberg excitation of all the components of upper atmosphere [S.V. Avakyan, The new factor in the physics of solar - terrestrial relations - Rydberg atomic and molecules states. Conf. on Physics of solar-terrestrial relationships, 1994, Almaty, 3 - 5]. In the present paper the results of bringing these new processes in the ionospheric physics are discussed and also its possible role in the physics of solar-terrestrial coupling is considered. Involving these processes to the model estimations allowed us for the first time to come to the following important conclusions: - Auger electrons play the determinant role at the formation of energy spectrum of photoelectrons and secondary auroral electrons at the range above 150 eV; - double photoionization of the outer shell of the oxygen atom (by a single photon) plays a dominant role in the formation of ionospheric doubly charged positive ions, and Auger effect mainly determines the formation of double- and triple charged ions in the low ionosphere of planets and also comets; - transitions in the Rydberg excited ionospheric atoms and molecules play the main role in generation of new type of upper atmospheric emission - microwave characteristic radiation. The ionospheric O++ ions fill the magnetosphere after geomagnetic storms. These ions scatter the solar radiation in one of the most intense lines with a wavelength of 30.4 nm (He+) and also in the 50.7-, 70.3-, 83.3-83.5-nm lines in geocorona to the nocturnal side, giving rise to additional ionization and optical excitation in the F-region. The first calculations of the excitation rate of Rydberg states by photoelectrons and by auroral electrons (including Auger electrons) were carried out. It was shown that such process can generate the microwave ionospheric radioemission. Such emissions were observed during solar flares and in auroras. We suggest that Rydberg microwave radioemissions which take place during ionospheric disturbances produced by the solar flares and geomagnetic storms can be considered as an agent of influence of solar-geomagnetic activity on the biosphere and also as a factor of Sun-weather-climate links All these results obtained experimental confirmation in space investigations and in some ground-based measurements carried out with radiophysical and optical methods. The new processes which we introduced to the physics of upper atmosphere and ionosphere are now widely used in the ionospheric science for interpretation of spacecraft measurement data (the spacecrafts ISIS, GEOS-1, IMAGE, the satellites DE-1,-B, EXOS-D (AKEBOHO), FAST, Intercosmos-19, -24, -25, the orbital stations "Salut", "Mir"). There is a Russian patent on the method of remote registration of radioactive atmospheric clouds and nuclear weapon tests over the atmosphere by means of optical fluorescence which is based on Auger processes.

Avakyan, Sergei

2010-05-01

455

Atomically abrupt and unpinned Al2O3/In0.53Ga0.47As interfaces: Experiment and simulation  

E-print Network

Atomically abrupt and unpinned Al2O3/In0.53Ga0.47As interfaces: Experiment and simulation Eun Ji an In0.53Ga0.47As 100 channel and an Al2O3 dielectric layer grown by atomic layer deposition ALD when0.47As 100 -4 2 surface followed by ALD of Al2O3 produced an atomically abrupt interface without

Kummel, Andrew C.

456

Coordination of Scheduling Clinical Externship or Clinical Practice Experiences for Students in Physical Therapy Educational Programs.  

ERIC Educational Resources Information Center

A project to coordinate the scheduling of allied health occupations students for clinical practice or externship experiences in Southeast Florida is described. A model clinical facility utilization and time schedule matrix was developed for four programs: the physical therapy programs at Florida International University (FIU) and the University of…

Patterson, Robert K.; Kass, Susan H.

457

Experiments Using Cell Phones in Physics Classroom Education: The Computer-Aided "g" Determination  

ERIC Educational Resources Information Center

This paper continues the collection of experiments that describe the use of cell phones as experimental tools in physics classroom education. We describe a computer-aided determination of the free-fall acceleration "g" using the acoustical Doppler effect. The Doppler shift is a function of the speed of the source. Since a free-falling objects…

Vogt, Patrik; Kuhn, Jochen; Muller, Sebastian

2011-01-01

458

On-line computer system for use with low- energy nuclear physics experiments is reported  

NASA Technical Reports Server (NTRS)

Computer program handles data from low-energy nuclear physics experiments which utilize the ND-160 pulse-height analyzer and the PHYLIS computing system. The program allows experimenters to choose from about 50 different basic data-handling functions and to prescribe the order in which these functions will be performed.

Gemmell, D. S.

1969-01-01