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1

Simulating the Daylight Performance of Complex Fenestration Systems Using Bidirectional Scattering Distribution Functions within Radiance  

SciTech Connect (OSTI)

We describe two methods which rely on bidirectional scattering distribution functions (BSDFs) to model the daylighting performance of complex fenestration systems (CFS), enabling greater flexibility and accuracy in evaluating arbitrary assemblies of glazing, shading, and other optically-complex coplanar window systems. Two tools within Radiance enable a) efficient annual performance evaluations of CFS, and b) accurate renderings of CFS despite the loss of spatial resolution associated with low-resolution BSDF datasets for inhomogeneous systems. Validation, accuracy, and limitations of the methods are discussed.

Ward, Gregory; Mistrick, Ph.D., Richard; Lee, Eleanor; McNeil, Andrew; Jonsson, Ph.D., Jacob

2011-01-21T23:59:59.000Z

2

Simulating the daylight performance of complex fenestration systems using bidirectional scattering distribution functions with  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

414E 414E Simulating the Daylight Performance of Complex Fenestration Systems Using Bidirectional Scattering Distribution Functions within Radiance G. Ward, R. Mistrick, E.S. Lee, A. McNeil, J. Jonsson Environmental Energy Technologies Division Building Technologies Department January 2011 Published in Leukos, Journal of the Illuminating Engineering Society of North America 7(4). DISCLAIMER This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor The Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information,

3

Obtaining the Bidirectional Transfer Distribution Function of Isotropically  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Obtaining the Bidirectional Transfer Distribution Function of Isotropically Obtaining the Bidirectional Transfer Distribution Function of Isotropically Scattering Materials Using an Integrating Sphere Title Obtaining the Bidirectional Transfer Distribution Function of Isotropically Scattering Materials Using an Integrating Sphere Publication Type Journal Article LBNL Report Number LBNL-61826 Year of Publication 2007 Authors Jonsson, Jacob C., and Henrik Branden Journal Optics Communications Volume 277 Pagination 228-236 Call Number LBNL-61826 Abstract This paper demonstrates a method to determine the bidirectional transfer distribution function (BTDF) using an integrating sphere. Information about the sample's angle dependent scattering is obtained by making transmittance measurements with the sample at different distances from the integrating sphere. Knowledge about the illuminated area of the sample and the geometry of the sphere port in combination with the measured data combines to an system of equations that includes the angle dependent transmittance. The resulting system of equations is an ill-posed problem which rarely gives a physical solution. A solvable system is obtained by using Tikhonov regularization on the ill-posed problem. The solution to this system can then be used to obtain the BTDF. Four bulk-scattering samples were characterised using both two goniophotometers and the described method to verify the validity of the new method. The agreement shown is great for the more diffuse samples. The solution to the low-scattering samples contains unphysical oscillations, but still gives the correct shape of the solution. The origin of the oscillations and why they are more prominent in low-scattering samples are discussed.

4

Bidirectional amplifier  

DOE Patents [OSTI]

A bilateral circuit is operable for transmitting signals in two directions without generation of ringing due to feedback caused by the insertion of the circuit. The circuit may include gain for each of the signals to provide a bidirectional amplifier. The signals are passed through two separate paths, with a unidirectional amplifier in each path. A controlled sampling device is provided in each path for sampling the two signals. Any feedback loop between the two signals is disrupted by providing a phase displacement between the control signals for the two sampling devices.

Wright, J.T.

1984-02-02T23:59:59.000Z

5

Bidirectional amplifier  

DOE Patents [OSTI]

A bilateral circuit is operable for transmitting signals in two directions without generation of ringing due to feedback caused by the insertion of the circuit. The circuit may include gain for each of the signals to provide a bidirectional amplifier. The signals are passed through two separate paths, with a unidirectional amplifier in each path. A controlled sampling device is provided in each path for sampling the two signals. Any feedback loop between the two signals is disrupted by providing a phase displacement between the control signals for the two sampling devices.

Wright, James T. (Cedarcrest, NM)

1986-01-01T23:59:59.000Z

6

Obtaining the Bidirectional Transfer Distribution Function of Isotropically Scattering Materials Using an Integrating Sphere  

E-Print Network [OSTI]

data a) UTS measurement N73d1 Optronics N73d1 Computed N73d1UTS measurement N73d3 Optronics N73d3 Computed N73d3 BTDF (? c) UTS measurement N77d1 Optronics N77d1 Computed N77d1 d)

Jonsson, Jacob C.; Branden, Henrik

2006-01-01T23:59:59.000Z

7

A Practical Framework for Sharing and Rendering Real-World Bidirectional  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

A Practical Framework for Sharing and Rendering Real-World Bidirectional A Practical Framework for Sharing and Rendering Real-World Bidirectional Scattering Distribution Functions Title A Practical Framework for Sharing and Rendering Real-World Bidirectional Scattering Distribution Functions Publication Type Report LBNL Report Number LBNL-5954E Year of Publication 2012 Authors Ward, Gregory J., Murat Kurt, and Nicolas Bonneel Date Published 10/2012 Keywords building technology and urban systems department, windows and envelope materials group Abstract The utilization of real-world materials has been hindered by a lack of standards for sharing and interpreting measured data. This paper presents an XML representation and an Open Source C library to support bidirectional scattering distribution functions (BSDFs) in data-driven lighting simulation and rendering applications.The library provides for the efficient representation, query, and Monte Carlo sampling of arbitrary BSDFs in amodel-free framework. Currently, we support two BSDF data representations: one using a fixed subdivision of thehemisphere, and one with adaptive density. The fixed type has advantages for certain matrix operations, while theadaptive type can more accurately represent highly peaked data. We discuss advanced methods for data-driven BSDF rendering for both types, including the proxy of detailed geometry to enhance appearance and accuracy. We also present an advanced interpolation method to reduce measured data into these standard representations. We end with our plan for future extensions and sharing of BSDF data.

8

A 16 mm3 autonomous solar-powered sensor node with bi-directional optical communication for distributed sensor net-  

E-Print Network [OSTI]

Abstract A 16 mm3 autonomous solar-powered sensor node with bi- directional optical communication for distributed sensor net- works has been demonstrated. The device digitizes inte- grated sensor signals, a 2.6 mm2 SOI solar cell array, and a micromachined four-quadrant corner-cube retroreflector (CCR

Kahn, Joseph M.

9

Proton Angular Distribution for 90 Mev Neutron-proton Scattering  

E-Print Network [OSTI]

PROTON SCATTERING James Hadley, Cecil E. Leith, and HerbertPRarON SCATTERING James Hadley, Cecil E. Leith, and Herbert

Hadley, James

2010-01-01T23:59:59.000Z

10

Bidirectional slapper detonator  

DOE Patents [OSTI]

The disclosure is directed to a bidirectional slapper detonator. One embodiment utilizes a single bridge circuit to detonate a pair of opposing initiating pellets. A line generator embodiment uses a plurality of bridges in electrical series to generate opposing cylindrical wavefronts.

McCormick, Robert N. (Los Alamos, NM); Boyd, Melissa D. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

11

Angular distribution of 6He+p elastic scattering  

Science Journals Connector (OSTI)

The angular distribution of 1H(6He,p)6He elastic scattering has been measured at Ec.m. = 4.3 MeV by using a thick-target inverse kinematic method. The experimental differential cross sections are reproduced by the distorted-wave Born approximation calculation utilizing the CH89 global optical potential parameter set. The real part of CH89 is reduced comparing with other potentials, which may be attributed to the couplings necessary for the weakly bound nuclei.

Liu Xin (??); Wang You-Bao (???); Li Zhi-Hong (???); Jin Sun-Jun (???); Wang Bao-Xiang (???); Li Yun-Ju (???); Li Er-Tao (???); Bai Xi-Xiang (???); Guo Bing (??); Su Jun (??); Zeng Sheng (??); Yan Sheng-Quan (???); Lian Gang (??); Huang Wu-Zhen (???); Liu Wei-Ping (???)

2012-01-01T23:59:59.000Z

12

Dynamic radial distribution function from inelastic neutron scattering  

Science Journals Connector (OSTI)

A real-space, local dynamic structure function g(r,?) is defined from the dynamic structure function S(Q,?), which can be measured using inelastic neutron scattering. At any particular frequency ?, S(Q,?) contains Q-dependent intensity oscillations which reflect the spatial distribution and relative displacement directions for the atoms vibrating at that frequency. Information about local and dynamic atomic correlations is obtained from the Fourier transform of these oscillations g(r,?) at the particular frequency. g(r,?) can be formulated such that the elastic and frequency-summed limits correspond to the average and instantaneous radial distribution function, respectively, and is thus called the dynamic radial distribution function. As an example, the dynamic radial distribution function is calculated for fcc nickel in a model which considers only the harmonic atomic displacements due to phonons. The results of these calculations demonstrate that the magnitude of the atomic correlations can be quantified and g(r,?) is a well-defined correlation function. This leads to a simple prescription for investigating local lattice dynamics.

R. J. McQueeney

1998-05-01T23:59:59.000Z

13

Proton Angular Distribution for 90 Mev Neutron-proton Scattering  

E-Print Network [OSTI]

recoil protons in neutron -proton scattering at 90 Mev hasFOR 90 lWEV NEUTRON-PROTON SCATTERING James Hadley, Cecil E.

Hadley, James

2010-01-01T23:59:59.000Z

14

Deeply virtual Compton scattering and generalized parton distributions at CLAS  

SciTech Connect (OSTI)

The exclusive electroproduction of real photons and mesons at high momentum transfer allows us to access the Generalized Parton Distributions (GPDs). The formalism of the GPDs provides a unified description of the hadronic structure in terms of quark and gluonic degrees of freedom. In particular, the Deeply Virtual Compton Scattering (DVCS), ep â e2p2Å , is one of the key reactions to determine the GPDs experimentally, as it is the simplest process that can be described in terms of GPDs. A dedicated experiment to study DVCS has been carried out in Hall B at Jefferson Lab. Beam-spin asymmetries, resulting from the interference of the Bethe-Heitler process and DVCS have been extracted over the widest kinematic range ever accessed for this reaction ( 1.2 < Q 2 < 3.7 (GeV/c 2, 0.09 < - t < 1.3 (GeV/c 2, 0.13 < x B < 0.46 . In this paper, the results obtained experimentally are shown and compared to GPD parametrizations.

Niccolai, Silvia

2008-11-01T23:59:59.000Z

15

Theoretical modeling for neutron elastic scattering angular distribution in the fast energy range  

SciTech Connect (OSTI)

One of the major issues of neutron scattering modeling in the fast energy range is the contribution of compound elastic and inelastic scattering to the total scattering process. The compound component may become large at very low energies where the angular distribution becomes 90-degree symmetric in the center-of-mass system. Together with the shape elastic component, the elastic scattering gives slightly forward-peaked angular distributions in the fast energy range. This anisotropic angular distribution gives high sensitivities to many important nuclear reactor characteristics, such as criticality and neutron shielding. In this talk we describe how the anisotropic angular distributions are calculated within the statistical model framework, including the case where strongly coupled channels exist, by combining the coupled-channels theory with the Hauser-Feshbach model. This unique capability extension will have significant advantages in understanding the neutron scattering process for deformed nuclei, like uranium or plutonium, on which advanced nuclear energy applications center.

Kawano, Toshihiko [Los Alamos National Laboratory

2010-12-07T23:59:59.000Z

16

Spatial frequency spectrum of the x-ray scatter distribution in CBCT projections  

SciTech Connect (OSTI)

Purpose: X-ray scatter is a source of significant image quality loss in cone-beam computed tomography (CBCT). The use of Monte Carlo (MC) simulations separating primary and scattered photons has allowed the structure and nature of the scatter distribution in CBCT to become better elucidated. This work seeks to quantify the structure and determine a suitable basis function for the scatter distribution by examining its spectral components using Fourier analysis.Methods: The scatter distribution projection data were simulated using a CBCT MC model based on the EGSnrc code. CBCT projection data, with separated primary and scatter signal, were generated for a 30.6 cm diameter water cylinder [single angle projection with varying axis-to-detector distance (ADD) and bowtie filters] and two anthropomorphic phantoms (head and pelvis, 360 projections sampled every 1°, with and without a compensator). The Fourier transform of the resulting scatter distributions was computed and analyzed both qualitatively and quantitatively. A novel metric called the scatter frequency width (SFW) is introduced to determine the scatter distribution's frequency content. The frequency content results are used to determine a set basis functions, consisting of low-frequency sine and cosine functions, to fit and denoise the scatter distribution generated from MC simulations using a reduced number of photons and projections. The signal recovery is implemented using Fourier filtering (low-pass Butterworth filter) and interpolation. Estimates of the scatter distribution are used to correct and reconstruct simulated projections.Results: The spatial and angular frequencies are contained within a maximum frequency of 0.1 cm{sup ?1} and 7/(2?) rad{sup ?1} for the imaging scenarios examined, with these values varying depending on the object and imaging setup (e.g., ADD and compensator). These data indicate spatial and angular sampling every 5 cm and ?/7 rad (?25°) can be used to properly capture the scatter distribution, with reduced sampling possible depending on the imaging scenario. Using a low-pass Butterworth filter, tuned with the SFW values, to denoise the scatter projection data generated from MC simulations using 10{sup 6} photons resulted in an error reduction of greater than 85% for the estimating scatter in single and multiple projections. Analysis showed that the use of a compensator helped reduce the error in estimating the scatter distribution from limited photon simulations by more than 37% when compared to the case without a compensator for the head and pelvis phantoms. Reconstructions of simulated head phantom projections corrected by the filtered and interpolated scatter estimates showed improvements in overall image quality.Conclusions: The spatial frequency content of the scatter distribution in CBCT is found to be contained within the low frequency domain. The frequency content is modulated both by object and imaging parameters (ADD and compensator). The low-frequency nature of the scatter distribution allows for a limited set of sine and cosine basis functions to be used to accurately represent the scatter signal in the presence of noise and reduced data sampling decreasing MC based scatter estimation time. Compensator induced modulation of the scatter distribution reduces the frequency content and improves the fitting results.

Bootsma, G. J. [Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 2M9, Canada and Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada)] [Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 2M9, Canada and Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada); Verhaegen, F. [Department of Radiation Oncology (MAASTRO), GROW – School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands) [Department of Radiation Oncology (MAASTRO), GROW – School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands); Department of Oncology, Medical Physics Unit, McGill University, Montreal, Quebec H3G 1A4 (Canada); Jaffray, D. A. [Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 2M9 (Canada) [Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada); Ontario Cancer Institute, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5G 2M9 (Canada)

2013-11-15T23:59:59.000Z

17

Next-to-leading order hard scattering using fully unintegrated parton distribution functions  

Science Journals Connector (OSTI)

We calculate the next-to-leading order fully unintegrated hard scattering coefficient for unpolarized gluon-induced deep inelastic scattering using the logical framework of parton correlation functions developed in previous work. In our approach, exact four-momentum conservation is maintained throughout the calculation. Hence, all nonperturbative functions, like parton distribution functions, depend on all components of parton four-momentum. In contrast to the usual collinear factorization approach where the hard scattering coefficient involves generalized functions (such as Dirac ? functions), the fully unintegrated hard scattering coefficient is an ordinary function. Gluon-induced deep inelastic scattering provides a simple illustration of the application of the fully unintegrated factorization formalism with a nontrivial hard scattering coefficient, applied to a phenomenologically interesting case. Furthermore, the gluon-induced process allows for a parametrization of the fully unintegrated gluon distribution function.

Ted C. Rogers

2008-10-17T23:59:59.000Z

18

Next-to-Leading Order Hard Scattering Using Fully Unintegrated Parton Distribution Functions  

E-Print Network [OSTI]

We calculate the next-to-leading order fully unintegrated hard scattering coefficient for unpolarized gluon-induced deep inelastic scattering using the logical framework of parton correlation functions developed in previous work. In our approach, exact four-momentum conservation is maintained throughout the calculation. Hence, all non-perturbative functions, like parton distribution functions, depend on all components of parton four-momentum. In contrast to the usual collinear factorization approach where the hard scattering coefficient involves generalized functions (such as Dirac $\\delta$-functions), the fully unintegrated hard scattering coefficient is an ordinary function. Gluon-induced deep inelastic scattering provides a simple illustration of the application of the fully unintegrated factorization formalism with a non-trivial hard scattering coefficient, applied to a phenomenologically interesting case. Furthermore, the gluon-induced process allows for a parameterization of the fully unintegrated gluon distribution function.

Ted C. Rogers

2008-09-29T23:59:59.000Z

19

Next-to-leading order hard scattering using fully unintegrated parton distribution functions  

SciTech Connect (OSTI)

We calculate the next-to-leading order fully unintegrated hard scattering coefficient for unpolarized gluon-induced deep inelastic scattering using the logical framework of parton correlation functions developed in previous work. In our approach, exact four-momentum conservation is maintained throughout the calculation. Hence, all nonperturbative functions, like parton distribution functions, depend on all components of parton four-momentum. In contrast to the usual collinear factorization approach where the hard scattering coefficient involves generalized functions (such as Dirac {delta} functions), the fully unintegrated hard scattering coefficient is an ordinary function. Gluon-induced deep inelastic scattering provides a simple illustration of the application of the fully unintegrated factorization formalism with a nontrivial hard scattering coefficient, applied to a phenomenologically interesting case. Furthermore, the gluon-induced process allows for a parametrization of the fully unintegrated gluon distribution function.

Rogers, Ted C. [Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

2008-10-01T23:59:59.000Z

20

Bidirectional buck boost converter  

DOE Patents [OSTI]

A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero. 20 figs.

Esser, A.A.M.

1998-03-31T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

J. Mol. Biol. (1975) 91, 101-120 A Neutron Scattering Study of the Distribution of Protein  

E-Print Network [OSTI]

J. Mol. Biol. (1975) 91, 101-120 A Neutron Scattering Study of the Distribution of Protein and RNA coli have been measured by neutron scattering experiments on the intact subunit. In addition the radius, 1972; Lutter et al., 1972), and neutron scattering (Engelman & Moore, 1972; Moore et al., 1974

22

AVTA: Bidirectional Fast Charging Report  

Broader source: Energy.gov [DOE]

The Vehicle Technologies Office's Advanced Vehicle Testing Activity carries out testing on a wide range of advanced vehicles and technologies on dynamometers, closed test tracks, and on-the-road. These results provide benchmark data that researchers can use to develop technology models and guide future research and development. The following report is an analysis of bi-directional fast charging, as informed by the AVTA's testing on plug-in electric vehicle charging equipment. This research was conducted by Idaho National Laboratory.

23

Second order classical perturbation theory for atom surface scattering: Analysis of asymmetry in the angular distribution  

SciTech Connect (OSTI)

A second order classical perturbation theory is developed and applied to elastic atom corrugated surface scattering. The resulting theory accounts for experimentally observed asymmetry in the final angular distributions. These include qualitative features, such as reduction of the asymmetry in the intensity of the rainbow peaks with increased incidence energy as well as the asymmetry in the location of the rainbow peaks with respect to the specular scattering angle. The theory is especially applicable to “soft” corrugated potentials. Expressions for the angular distribution are derived for the exponential repulsive and Morse potential models. The theory is implemented numerically to a simplified model of the scattering of an Ar atom from a LiF(100) surface.

Zhou, Yun, E-mail: zhou.yun.x@gmail.com; Pollak, Eli, E-mail: eli.pollak@weizmann.ac.il [Chemical Physics Department, Weizmann Institute of Science, 76100 Rehovot (Israel)] [Chemical Physics Department, Weizmann Institute of Science, 76100 Rehovot (Israel); Miret-Artés, Salvador, E-mail: s.miret@iff.csic.es [Instituto de Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 123, 28006 Madrid (Spain)] [Instituto de Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 123, 28006 Madrid (Spain)

2014-01-14T23:59:59.000Z

24

Phenomenological description of bidirectional surface reflection  

E-Print Network [OSTI]

Phenomenological description of bidirectional surface reflection Jan J. Koenderink and Andrea J satellites). In some cases one has (usually approximate, phenomenological) models, but in most cases one

O'Brien, James F.

25

A landscape of bidirectional model transformations  

E-Print Network [OSTI]

A landscape of bidirectional model transformations Perdita Stevens Laboratory for Foundations the landscape of bidirectional model transformations as it appears to the author at the time of writing, autumn and maintenance more efficient by automating routine aspects of the process. For example, a com- mon scenario

Stevens, Perdita

26

Scattering  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Scattering Print Scattering Print When a crystalline sample is illuminated with x-rays, the x-rays are scattered (diffracted) into very specific directions with various intensities. Detectors are used to measure this "diffraction pattern," which is then processed by computers to deduce the arrangement of atoms within the crystal. Hard x-rays have wavelengths comparable to the distance between atoms. Essentially everything we know about the atomic structure of materials is based on results from x-ray and neutron diffraction. From advanced ceramics to catalysts, from semiconductor technology to the frontiers of medicine, and from new magnetic materials and devices to framework compounds used to sequester radioactive waste, crystallography using hard x-ray diffraction techniques at synchrotron radiation facilities plays a crucial role in our ability to understand and control the world in which we live.

27

Scattering  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Scattering Print Scattering Print When a crystalline sample is illuminated with x-rays, the x-rays are scattered (diffracted) into very specific directions with various intensities. Detectors are used to measure this "diffraction pattern," which is then processed by computers to deduce the arrangement of atoms within the crystal. Hard x-rays have wavelengths comparable to the distance between atoms. Essentially everything we know about the atomic structure of materials is based on results from x-ray and neutron diffraction. From advanced ceramics to catalysts, from semiconductor technology to the frontiers of medicine, and from new magnetic materials and devices to framework compounds used to sequester radioactive waste, crystallography using hard x-ray diffraction techniques at synchrotron radiation facilities plays a crucial role in our ability to understand and control the world in which we live.

28

High-energy Electron Scattering and the Charge Distributions of Selected Nuclei  

DOE R&D Accomplishments [OSTI]

Experimental results are presented of electron scattering by Ca, V, Co, In, Sb, Hf, Ta, W, Au, Bi, Th, and U, at 183 Mev and (for some of the elements) at 153 Mev. For those nuclei for which asphericity and inelastic scattering are absent or unimportant, i.e., Ca, V, Co, In, Sb, Au, and Bi, a partial wave analysis of the Dirac equation has been performed in which the nuclei are represented by static, spherically symmetric charge distributions. Smoothed uniform charge distributions have been assumed; these are characterized by a constant charge density in the central region of the nucleus, with a smoothed-our surface. Essentially two parameters can be determined, related to the radium and to the surface thickness. An examination of the Au experiments show that the functional forms of the surface are not important, and that the charge density in the central regions is probably fairly flat, although it cannot be determined very accurately.

Hahn, B.; Ravenhall, D. G.; Hofstadter, R.

1955-10-00T23:59:59.000Z

29

Bi-directional Ultra-Wideband Services over Large-Core POF-PON based Home Networks  

Science Journals Connector (OSTI)

Bi-directional transmission of ultra-wideband wireless signals over 1 mm core diameter POF for PON-based in-home network is demonstrated. Standard compliant signal distribution over 50...

Shi, Yan; Okonkwo, Chigo; Tangdiongga, Eduward; Koonen, A

30

Leading neutron energy and pT distributions in deep inelastic scattering and photoproduction at HERA  

E-Print Network [OSTI]

The production of energetic neutrons in $ep$ collisions has been studied with the ZEUS detector at HERA. The neutron energy and $p_T^2$ distributions were measured with a forward neutron calorimeter and tracker in a $40 \\pb^{-1}$ sample of inclusive deep inelastic scattering (DIS) data and a $6 \\pb^{-1}$ sample of photoproduction data. The neutron yield in photoproduction is suppressed relative to DIS for the lower neutron energies and the neutrons have a steeper $p_T^2$ distribution, consistent with the expectation from absorption models. The distributions are compared to HERA measurements of leading protons. The neutron energy and transverse-momentum distributions in DIS are compared to Monte Carlo simulations and to the predictions of particle exchange models. Models of pion exchange incorporating absorption and additional secondary meson exchanges give a good description of the data.

ZEUS Collaboration; S. Chekanov

2007-02-19T23:59:59.000Z

31

Polarized light propagation in highly scattering turbid media with a distribution of the particle size: a Monte Carlo study  

E-Print Network [OSTI]

The light propagation in highly scattering turbid media composed of the particles with different size distribution is studied using a Monte Carlo simulation model implemented in Standard C. Monte Carlo method has been widely utilized to study...

Koh, Wonshill

2013-02-22T23:59:59.000Z

32

Spatial Convergence of Bidirectional Reflectance Models  

Science Journals Connector (OSTI)

Analyses of bidirectional reflectance data are presented with implications regarding the spatial scales appropriate for inferring irradiances from radiances reflected by various surface–atmosphere scenes. Multiple-angle radiance data collected in ...

John M. Davis; Stephen K. Cox

1998-10-01T23:59:59.000Z

33

An efficient strategy for the inversion of bidirectional reflectance models with satellite remote sensing data  

SciTech Connect (OSTI)

The angular distribution of radiation scattered by the earth surface contains information on the structural and optical properties of the surface. Potentially, this information may be retrieved through the inversion of surface bidirectional reflectance distribution function (BRDF) models. This report details the limitations and efficient application of BRDF model inversions using data from ground- and satellite-based sensors. A turbid medium BRDF model, based on the discrete ordinates solution to the transport equation, was used to quantify the sensitivity of top-of-canopy reflectance to vegetation and soil parameters. Results were used to define parameter sets for inversions. Using synthetic reflectance values, the invertibility of the model was investigated for different optimization algorithms, surface and sampling conditions. Inversions were also conducted with field data from a ground-based radiometer. First, a soil BRDF model was inverted for different soil and sampling conditions. A condition-invariant solution was determined and used as the lower boundary condition in canopy model inversions. Finally, a scheme was developed to improve the speed and accuracy of inversions.

Privette, J.L.

1994-12-31T23:59:59.000Z

34

Proton elastic scattering from tin isotopes at 295 MeV and systematic change of neutron density distributions  

E-Print Network [OSTI]

Cross sections and analyzing powers for proton elastic scattering from $^{116,118,120,122,124}$Sn at 295 MeV have been measured for a momentum transfer of up to about 3.5 fm$^{-1}$ to deduce systematic changes of the neutron density distribution. We tuned the relativistic Love-Franey interaction to explain the proton elastic scattering of a nucleus whose density distribution is well known. Then, we applied this interaction to deduce the neutron density distributions of tin isotopes. The result of our analysis shows the clear systematic behavior of a gradual increase in the neutron skin thickness of tin isotopes with mass number.

S. Terashima; H. Sakaguchi; H. Takeda; T. Ishikawa; M. Itoh; T. Kawabata; T. Murakami; M. Uchida; Y. Yasuda; M. Yosoi; J. Zenihiro; H. P. Yoshida; T. Noro; T. Ishida; S. Asaji; T. Yonemura

2008-01-20T23:59:59.000Z

35

Ion distributions at charged aqueous surfaces: Synchrotron X-ray scattering studies  

SciTech Connect (OSTI)

Surface sensitive synchrotron X-ray scattering studies were performed to obtain the distribution of monovalent ions next to a highly charged interface at room temperature. To control surface charge density, lipids, dihexadecyl hydrogen-phosphate (DHDP) and dimysteroyl phosphatidic acid (DMPA), were spread as monolayer materials at the air/water interface, containing CsI at various concentrations. Five decades in bulk concentrations (CsI) are investigated, demonstrating that the interfacial distribution is strongly dependent on bulk concentration. We show that this is due to the strong binding constant of hydronium H3O+ to the phosphate group, leading to proton-transfer back to the phosphate group and to a reduced surface charge. Using anomalous reflectivity off and at the L3 Cs+ resonance, we provide spatial counterion (Cs+) distributions next to the negatively charged interfaces. The experimental ion distributions are in excellent agreement with a renormalized surface charge Poisson-Boltzmann theory for monovalent ions without fitting parameters or additional assumptions. Energy Scans at four fixed momentum transfers under specular reflectivity conditions near the Cs+ L3 resonance were conducted on 10-3 M CsI with DHDP monolayer materials on the surface. The energy scans exhibit a periodic dependence on photon momentum transfer. The ion distributions obtained from the analysis are in excellent agreement with those obtained from anomalous reflectivity measurements, providing further confirmation to the validity of the renormalized surface charge Poisson-Boltzmann theory for monovalent ions. Moreover, the dispersion corrections f0 and f00 for Cs+ around L3 resonance, revealing the local environment of a Cs+ ion in the solution at the interface, were extracted simultaneously with output of ion distributions.

Bu, Wei

2009-08-15T23:59:59.000Z

36

Bidirectional Fluxes of Nearly Relativistic Electrons During the Onset of Solar Energetic Particle Events  

Science Journals Connector (OSTI)

We report intensity and anisotropy measurements of energetic electrons in the energy range of ~27-~500 keV as observed with the Wind and Advanced Composition Explorer (ACE) spacecraft in 2000 June for several solar energetic particle (SEP) events. The solar sources of the SEP events are inferred from observations from the Solar and Heliospheric Observatory spacecraft. All of the events originate from the western limb active regions (ARs), which are well connected by interplanetary magnetic field (IMF) lines linking the Sun to near-Earth space. The observations on board Wind show bimodal pitch angle distributions (PADs), whereas ACE shows PADs with one peak, as is usually observed for impulsive injection of electrons at the Sun. During the time of observations, Wind was located, upstream of the Earth's bow shock in the dawn-noon sector, at distances of ~40-~80 RE from the Earth, and we infer that it was magnetically connected to the quasi-parallel bow shock. Meanwhile, ACE, orbiting the Sun-Earth libration point L1, was not connected to the bow shock. The electron intensity-time profiles and the energy spectra show that the backstreaming electrons observed at Wind are not of magnetospheric origin. The observations suggest rather that the bidirectional electron fluxes are due to reflection or scattering by an obstacle located at a distance of less than ~150 RE in the anti-sunward direction, which is compatible with the obstacle being the Earth's bow shock or magnetosheath.

L. P. Sun; C. Li

2013-01-01T23:59:59.000Z

37

Bidirectional Technology Transfer: Sabbaticals in Industry  

E-Print Network [OSTI]

Bidirectional Technology Transfer: Sabbaticals in Industry Mark D. Hill University of Wisconsin---not just technology transfer---through a ten­month sabbatical in an industrial product group. I advocate product group. The next sections discuss technology transfer, my recent sabbatical, and conclude

Hill, Mark D.

38

Unpolarised TMD Distribution and Fragmentation Functions from recent HERMES and COMPASS Semi-inclusive Deep Inelastic Scattering Multiplicities  

SciTech Connect (OSTI)

The unpolarised transverse momentum dependent distribution and fragmentation functions (TMDs) are extracted from HERMES and COMPASS experimental measurements of semi- inclusive deep inelastic scattering multiplicities for charged hadron production. A simple factorised functional form of the TMDs is adopted, with a Gaussian dependence on the intrinsic transverse momentum, which turns out to be quite adequate in shape.

Prokudin, Alexey; Anselmino, Mauro; Boglione, Mariaelena; Melis, Stefano; Gonzalez, J. O.

2014-10-01T23:59:59.000Z

39

On-the-fly generation of differential resonance scattering probability distribution functions for Monte Carlo codes  

SciTech Connect (OSTI)

Current Monte Carlo codes use one of three models to model neutron scattering in the epithermal energy range: (1) the asymptotic scattering model, (2) the free gas scattering model, or (3) the S({alpha},{beta}) model, depending on the neutron energy and the specific Monte Carlo code. The free gas scattering model assumes the scattering cross section is constant over the neutron energy range, which is usually a good approximation for light nuclei, but not for heavy nuclei where the scattering cross section may have several resonances in the epithermal region. Several researchers in the field have shown that using the free gas scattering model in the vicinity of the resonances in the lower epithermal range can under-predict resonance absorption due to the up-scattering phenomenon. Existing methods all involve performing the collision analysis in the center-of-mass frame, followed by a conversion back to the laboratory frame. In this paper, we will present a new sampling methodology that (1) accounts for the energy-dependent scattering cross sections in the collision analysis and (2) acts in the laboratory frame, avoiding the conversion to the center-of-mass frame. The energy dependence of the scattering cross section was modeled with even-ordered polynomials to approximate the scattering cross section in Blackshaw's equations for the moments of the differential scattering PDFs. These moments were used to sample the outgoing neutron speed and angle in the laboratory frame on-the-fly during the random walk of the neutron. Results for criticality studies on fuel pin and fuel assembly calculations using these methods showed very close comparison to results using the reference Doppler-broadened rejection correction (DBRC) scheme. (authors)

Sunny, E. E.; Martin, W. R. [University of Michigan, 2355 Bonisteel Boulevard, Ann Arbor MI 48109 (United States)

2013-07-01T23:59:59.000Z

40

CHARACTERIZING THE SPACE OF INTERATOMIC DISTANCE DISTRIBUTION FUNCTIONS CONSISTENT WITH SOLUTION SCATTERING DATA  

E-Print Network [OSTI]

SCATTERING DATA Paritosh A. Kavathekar Department of Computer Science, Dartmouth College, Hanover, NH 03755 of Computer Science, Dartmouth College, Hanover, NH 0375 Email: devin@cs.dartmouth.edu Abstract: Scattering of neutrons and x-rays from molecules in solution offers alternative approaches to the studying of a wide

Bailey-Kellogg, Chris

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Measurement of spin wave instability magnon distributions for subsidiary absorption in yttrium iron garnet films by Brillouin light scattering  

Science Journals Connector (OSTI)

The first evidence for a wide distribution in the critical mode wave vectors above the spin wave instability threshold for subsidiary absorption is reported. The Brillouin light scattering BLS measurements were done on 4.15 ?m thick yttrium iron garnet films with the static field and the 8.47 GHz linearly polarized microwave field in plane. The distribution in the critical mode wave number is broad, with widths of about 0.5×104–2×104 cm-1 and shapes which change with field and power. These results cast doubts on the validity of simple two mode models for the analysis of self-oscillation, chaos, and related effects above threshold.

P. Kabos; G. Wiese; C. E. Patton

1994-03-28T23:59:59.000Z

42

Behavior of Bidirectional Spring Unit in Isolated Floor Systems  

E-Print Network [OSTI]

gravity based sys- tems suspension mechanisms or linear spring based systems coil springs or rubber unitsBehavior of Bidirectional Spring Unit in Isolated Floor Systems Shenlei Cui, M.ASCE1 ; Michel of bidirectional spring units used as isolators in a kind of isolated floor system, three types of characterization

Bruneau, Michel

43

Neutrino-nucleus coherent scattering as a probe of neutron density distributions  

E-Print Network [OSTI]

Neutrino-nucleus coherent elastic scattering provides a theoretically appealing way to measure the neutron part of nuclear form factors. Using an expansion of form factors into moments, we show that neutrinos from stopped pions can probe not only the second moment of the form factor (the neutron radius) but also the fourth moment. Using simple Monte Carlo techniques for argon, germanium, and xenon detectors of 3.5 tonnes, 1.5 tonnes, and 300 kg, respectively, we show that the neutron radii can be found with an uncertainty of a few percent when near a neutrino flux of $3\\times10^{7}$ neutrinos/cm$^{2}$/s. If the normalization of the neutrino flux is known independently, one can determine the moments accurately enough to discriminate among the predictions of various nuclear energy functionals.

Kelly Patton; Jonathan Engel; Gail C. McLaughlin; Nicolas Schunck

2012-07-03T23:59:59.000Z

44

Preliminary results on the empirical applicability of the Tsallis distribution in elastic hadron scattering  

SciTech Connect (OSTI)

We show that the proton-proton elastic differential cross section data at dip position and beyond can be quite well described by a parametrization based on the Tsallis distribution, with only five free fit parameters. Extrapolation of the results obtained at 7 TeV to large momentum transfer, suggests that hadrons may not behave as a black-disk at the asymptotic energy region.

Fagundes, D. A.; Menon, M. J.; Silva, P. V. [Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP 13083-859 Campinas, SP (Brazil)

2013-03-25T23:59:59.000Z

45

Simultaneous Retrieval of Effective Refractive Index and Density from Size Distribution and Light Scattering Data: Weakly-Absorbing Aerosol  

SciTech Connect (OSTI)

We propose here a novel approach for retrieving in parallel the effective density and real refractive index of weakly absorbing aerosol from optical and size distribution measurements. Here we define “weakly absorbing” as aerosol single-scattering albedos that exceed 0.95 at 0.5 um.The required optical measurements are the scattering coefficient and the hemispheric backscatter fraction, obtained in this work from an integrating nephelometer. The required size spectra come from a Scanning Mobility Particle Sizer and an Aerodynamic Particle Sizer. The performance of this approach is first evaluated using a sensitivity study with synthetically generated but measurement-related inputs. The sensitivity study reveals that the proposed approach is robust to random noise; additionally the uncertainties of the retrieval are almost linearly proportional to the measurement errors, and these uncertainties are smaller for the real refractive index than for the effective density. Next, actual measurements are used to evaluate our approach. These measurements include the optical, microphysical, and chemical properties of weakly absorbing aerosol which are representative of a variety of coastal summertime conditions observed during the Two-Column Aerosol Project (TCAP; http://campaign.arm.gov/tcap/). The evaluation includes calculating the root mean square error (RMSE) between the aerosol characteristics retrieved by our approach, and the same quantities calculated using the conventional volume mixing rule for chemical constituents. For dry conditions (defined in this work as relative humidity less than 55%) and sub-micron particles, a very good (RMSE~3%) and reasonable (RMSE~28%) agreement is obtained for the retrieved real refractive index (1.49±0.02) and effective density (1.68±0.21), respectively. Our approach permits discrimination between the retrieved aerosol characteristics of sub-micron and sub-10micron particles. The evaluation results also reveal that the retrieved density and refractive index tend to decrease with an increase of the relative humidity.

Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Berg, Larry K.; Shilling, John E.; Flynn, Connor J.; Mei, Fan; Jefferson, Anne

2014-10-01T23:59:59.000Z

46

E-Print Network 3.0 - average bidirectional flow Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

to the bidirectional flow of either a liquid or a gas in the cylindrical portion of the tube (0 z l). vortex finder... of the bidirectional vortex, its distinct ... Source:...

47

Microstructural and textural evolution of AZ61 magnesium alloy sheet during bidirectional cyclic bending  

SciTech Connect (OSTI)

In this work, the microstructural and textural evolution in the sheets of AZ61 magnesium alloy was studied by means of bidirectional cyclic bending for 8 passes at 623 K. The bended samples were examined by optical microscopy and electron backscatter diffraction analysis. The results showed that a gradient structure with fine grains about 3 ?m in the regions near two surfaces and, in contrast, coarse grains in the middle of the sheet were formed. The evident grain refinement was attributed to twin-assisted dynamic recrystallization and continuous dynamic recrystallization induced by kink bands. The texture intensity was clearly reduced, resulting in a negative gradient distribution, with the texture intensity decreases from the center of the sheet to two surfaces. The weakened texture greatly facilitated the reduction of the yield strength. A higher fracture elongation and a slightly improved ultimate tensile strength were achieved concurrently. - Highlights: • The AZ61 Mg alloy is deformed at 623 K by bidirectional cyclic bending. • A symmetric gradient distribution of fine grains along the thickness is formed. • The basal texture in the regions near two surfaces is weakened significantly.

Huo, Qinghuan; Yang, Xuyue, E-mail: yangxuyue@mail.csu.edu.cn; Ma, Jijun; Sun, Huan; Qin, Jia; Jiang, Yupei

2013-05-15T23:59:59.000Z

48

The Energy Cost of Mandatory Bidirectionality in Wireless Multimedia Communication  

E-Print Network [OSTI]

The Energy Cost of Mandatory Bidirectionality in Wireless Multimedia Communication Xiaoyu Chu to have high energy costs in new application do- mains involving multimedia. In this paper, we examine the energy cost of an old, simple and pervasive feature in wireless medium access control protocols

Sethu, Harish

49

A Bidirectional High-Power-Quality Grid Interface With a Novel Bidirectional Noninverted Buck Boost Converter for PHEVs  

SciTech Connect (OSTI)

Plug-in hybrid electric vehicles (PHEVs) will play a vital role in future sustainable transportation systems due to their potential in terms of energy security, decreased environmental impact, improved fuel economy, and better performance. Moreover, new regulations have been established to improve the collective gas mileage, cut greenhouse gas emissions, and reduce dependence on foreign oil. This paper primarily focuses on two major thrust areas of PHEVs. First, it introduces a grid-friendly bidirectional alternating current/direct current ac/dc dc/ac rectifier/inverter for facilitating vehicle-to-grid (V2G) integration of PHEVs. Second, it presents an integrated bidirectional noninverted buck boost converter that interfaces the energy storage device of the PHEV to the dc link in both grid-connected and driving modes. The proposed bidirectional converter has minimal grid-level disruptions in terms of power factor and total harmonic distortion, with less switching noise. The integrated bidirectional dc/dc converter assists the grid interface converter to track the charge/discharge power of the PHEV battery. In addition, while driving, the dc/dc converter provides a regulated dc link voltage to the motor drive and captures the braking energy during regenerative braking.

Onar, Omer C [ORNL

2012-01-01T23:59:59.000Z

50

V. Havran & J. Filip & K. Myszkowski / Bidirectional Texture Function Compression Based on Multi-Level Vector Quantization Bidirectional Texture Function Compression Based on  

E-Print Network [OSTI]

and illumination dependent texels into a set of multidimensional conditional probability density functionsV. Havran & J. Filip & K. Myszkowski / Bidirectional Texture Function Compression Based on Multi-Level Vector Quantization Bidirectional Texture Function Compression Based on Multi-Level Vector Quantization V

Havran, Vlastimil

51

Bichromatic emission and multimode dynamics in bidirectional ring lasers  

SciTech Connect (OSTI)

The multimode dynamics of a two-level ring laser is explored numerically using a bidirectional traveling wave model retaining the spatial effects due to the presence of counter-propagating electric fields in the population inversion. Dynamical regimes where the emission in each direction occurs at different wavelengths are studied. Mode-locked unidirectional emission for large gain bandwidth and relatively small detuning is reported.

Perez-Serrano, Antonio; Javaloyes, Julien; Balle, Salvador [Instituto de Fisica Interdisciplinar y Sistemas Complejos, IFISC, UIB-CSIC, Campus UIB, Palma de Mallorca, E-07122 (Spain); Department of Electronics and Electrical Engineering, University of Glasgow, Glasgow, G12 8LT (United Kingdom); Institut Mediterrani d'Estudis Avancats, IMEDEA, UIB-CSIC, Esporles, E-07190 (Spain)

2010-04-15T23:59:59.000Z

52

A stochastic model for kinesin bidirectional stepping  

SciTech Connect (OSTI)

In this paper, a hand-over-hand stochastic model for the dynamics of the conventional kinesin is constructed. In the model, both forward and backward motions are taken into consideration. First passage time distributions, average velocities, dwell times, and forward/backward step ratios are investigated based on the model. A good agreement between the results of the model and experimental data is achieved under a variety of external loads.

Yao, Xiaojun [School of Physics, Shandong University, Jinan 250100 (China) [School of Physics, Shandong University, Jinan 250100 (China); Taishan College, Shandong University, Jinan 250100 (China); Zheng, Yujun, E-mail: yzheng@sdu.edu.cn [School of Physics, Shandong University, Jinan 250100 (China)] [School of Physics, Shandong University, Jinan 250100 (China)

2014-02-28T23:59:59.000Z

53

A comparison of the energy distributions of hadrons produced in deep inelastic scattering of muons on hydrogen and deuterium targets  

Science Journals Connector (OSTI)

The energy distribution of inclusive hadrons produced by 280 GeV muons on hydrogen and deuterium targets are compared. The sum of the scaled energy distributions of the positive and negative hadrons...x andz and ...

J. J. Aubert; G. Bassompierre; K. H. Becks…

1986-01-01T23:59:59.000Z

54

Bi-directional Multi Dimension CAP Transmission for Smart Grid Communication Services  

Science Journals Connector (OSTI)

We experimentally demonstrate bi-directional multi dimension carrierless amplitude and phase (CAP) transmission for smart grid communication services based on optical fiber...

Zhang, Xu; Othman, Maisara B; Pang, Xiaodan; Jensen, Jesper Bevensee; Monroy, Idelfonso Tafur

55

Study of Generalized Parton Distributions and Deeply Virtual Compton Scattering on the nucleon with the CLAS and CLAS12 detectors at the Jefferson Laboratory  

SciTech Connect (OSTI)

The exclusive leptoproduction of a real photon is considered to be the "cleanest" way to access the Generalized Parton Distribution (GPD). This process is called Deeply Virtual Compton Scattering (DVCS) lN {yields} lN{gamma} , and is sensitive to all the four GPDs. Measuring the DVCS cross section is one of the main goals of this thesis. In this thesis, we present the work performed to extract on a wide phase-space the DVCS cross-section from the JLab data at a beam energy of 6 GeV.

Baptiste Guegan

2012-11-01T23:59:59.000Z

56

EXPERIMENTAL STUDY OF BI-DIRECTIONAL SPRING UNIT IN ISOLATED FLOOR SYSTEMS  

E-Print Network [OSTI]

) or linear spring based systems (coil springs or rubber units used for restoration force), with viscousEXPERIMENTAL STUDY OF BI-DIRECTIONAL SPRING UNIT IN ISOLATED FLOOR SYSTEMS Shenlei Cui1 , Michel the mechanical behavior of bi-directional spring units used as isolators in a kind of such isolated floor systems

Bruneau, Michel

57

Active Flow Control on Bidirectional Rotors for Tidal MHK Applications  

SciTech Connect (OSTI)

A marine and hydrokinetic (MHK) tidal turbine extracts energy from tidal currents, providing clean, sustainable electricity generation. In general, all MHK conversion technologies are confronted with significant operational hurdles, resulting in both increased capital and operations and maintenance (O&M) costs. To counter these high costs while maintaining reliability, MHK turbine designs can be simplified. Prior study found that a tidal turbine could be cost-effectively simplified by removing blade pitch and rotor/nacelle yaw. Its rotor would run in one direction during ebb and then reverse direction when the current switched to flood. We dubbed such a turbine a bidirectional rotor tidal turbine (BRTT). The bidirectional hydrofoils of a BRTT are less efficient than conventional hydrofoils and capture less energy, but the elimination of the pitch and yaw systems were estimated to reduce levelized cost of energy by 7.8%-9.6%. In this study, we investigated two mechanisms for recapturing some of the performance shortfall of the BRTT. First, we developed a novel set of hydrofoils, designated the yy series, for BRTT application. Second, we investigated the use of active flow control via microtabs. Microtabs are small deployable/retractable tabs, typically located near the leading or trailing edge of an air/hydrofoil with height on the order of the boundary layer thickness (1% - 2% of chord). They deploy approximately perpendicularly to the foil surface and, like gurney flaps and plain flaps, globally affect the aerodynamics of the airfoil. By strategically placing microtabs and selectively deploying them based on the direction of the inflow, performance of a BRTT rotor can be improved while retaining bidirectional operation. The yy foils were computationally designed and analyzed. They exhibited better performance than the baseline bidirectional foil, the ellipse. For example, the yyb07cn-180 had 14.7% higher (l/d)max than an ellipse of equal thickness. The yyb07cn family also had higher c{sub p,min} than equivalently thick ellipses, indicating less susceptibility to cavitation. Microtabs applied on yy foils demonstrated improved energy capture. A series of variable speed and constant speed rotors were developed with the yyb07cn family of hydrofoils. The constant speed yyb07cn rotor (yy-B02-Rcs,opt) captured 0.45% more energy than the equivalent rotor with ellipses (e-B02-Rcs,opt). With microtabs deployed (yy?t-B02-Rcs,opt), the energy capture increase over the rotor with ellipses was 1.05%. Note, however, that microtabs must be applied judiciously to bidirectional foils. On the 18% thick ellipse, performance decreased with the addition of microtabs. Details of hydrofoil performance, microtab sizing and positioning, rotor configurations, and revenue impacts are presented herein.

Shiu, Henry [Research Engineer; van Dam, Cornelis P. [Professor

2013-08-22T23:59:59.000Z

58

Convective flow of sisko fluid over a bidirectional stretching sheet  

E-Print Network [OSTI]

The present investigation discusses the flow and heat transfer characteristics of a steady three dimensional Sisko fluid. The flow is induced due to bidirectional stretching sheet. The influence of power-law index and stretching ratio on flow and heat transfer is studied thoroughly. Governing partial differential equations are reduced to coupled ordinary differential equations by suitable similarity variable. The resulting equations are then solved numerically by shooting method using adaptive Runge Kutta algorithm in combination with Broyden's method in the domain . The numerical results for the velocity and temperature fields are graphically presented and effects of the relevant parameters are discussed in detail. Moreover, the skin-friction coefficient and local Nusselt number for different values of the power-law index and stretching ratio are presented through tabulated data. The numerical results are verified with the results obtained by HAM. Additionally, the results are also validated with previously ...

Munir, Asif; Khan, Masood

2014-01-01T23:59:59.000Z

59

Chevron beam dump for ITER edge Thomson scattering system  

SciTech Connect (OSTI)

This paper contains the design of the beam dump for the ITER edge Thomson scattering system and mainly concerns its lifetime under the harsh thermal and electromagnetic loads as well as tight space allocation. The lifetime was estimated from the multi-pulse laser-induced damage threshold. In order to extend its lifetime, the structure of the beam dump was optimized. A number of bent sheets aligned parallel in the beam dump form a shape called a chevron which enables it to avoid the concentration of the incident laser pulse energy. The chevron beam dump is expected to withstand thermal loads due to nuclear heating, radiation from the plasma, and numerous incident laser pulses throughout the entire ITER project with a reasonable margin for the peak factor of the beam profile. Structural analysis was also carried out in case of electromagnetic loads during a disruption. Moreover, detailed issues for more accurate assessments of the beam dump's lifetime are clarified. Variation of the bi-directional reflection distribution function (BRDF) due to erosion by or contamination of neutral particles derived from the plasma is one of the most critical issues that needs to be resolved. In this paper, the BRDF was assumed, and the total amount of stray light and the absorbed laser energy profile on the beam dump were evaluated.

Yatsuka, E.; Hatae, T.; Bassan, M.; Itami, K. [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)] [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Vayakis, G. [ITER Organization, 13115 St Paul Lez Durance Cedex (France)] [ITER Organization, 13115 St Paul Lez Durance Cedex (France)

2013-10-15T23:59:59.000Z

60

Multiple-scattering effects on smooth neutron-scattering spectra  

Science Journals Connector (OSTI)

Elastic and inelastic incoherent neutron-scattering experiments are simulated for simple models: a rigid solid (as used for normalization), a glass (with a smooth distribution of harmonic vibrations), and a viscous liquid (described by schematic mode-coupling equations). In cases where the input scattering law factorizes into a wave-number-dependent amplitude and a frequency-dependent spectral distribution, the latter is only weakly affected by multiple scattering, whereas the former is severely distorted.

Joachim Wuttke

2000-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Bidirectional External Function Interface Between Modelica/MetaModelica and Java.  

E-Print Network [OSTI]

?? A complete Java interface to OpenModelica has been created, supporting both standard Modelica and the metamodeling extensions in MetaModelica. It is bidirectional, and capable… (more)

Sjölund, Martin

2009-01-01T23:59:59.000Z

62

Graphene-based passively mode-locked bidirectional fiber ring laser  

Science Journals Connector (OSTI)

We present an all-fiber bidirectional passively mode-locked soliton laser with a graphene-based saturable absorber for the first time to the best of our knowledge. Our design includes...

Mamidala, Venkatesh; Woodward, R I; Yang, Y; Liu, H H; Chow, K K

2014-01-01T23:59:59.000Z

63

Distribution:  

Office of Legacy Management (LM)

JAN26 19% JAN26 19% Distribution: OR00 Attn: h.H.M.Roth DFMusser ITMM MMMann INS JCRyan FIw(2) Hsixele SRGustavson, Document rocm Formal file i+a@mmm bav@ ~@esiaw*cp Suppl. file 'Br & Div rf's s/health (lic.only) UNITED STATES ATOMIC ENERGY COMMISSION SPECIAL NUCLEAB MATERIAL LICENSE pursuant to the Atomic Energy Act of 1954 and Title 10, Code of Federal Regulations, Chapter 1, P&t 70, "Special Nuclear Material Reg)llatiqm," a license is hereby issued a$hortztng the licensee to rekeive and possess the special nuclear material designated below; to use such special nuclear mat&ial for the purpose(s) and at the place(s) designated below; and to transfer such material to per&s authorized to receive it in accordance with the regula,tions in said Part.

64

Neutron Scattering Software  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Software Software A new portal for neutron scattering has just been established at neutronsources.org. The information contained here in the Neutron Scattering Web has been transferred to the new site. We will leave the current content here for archival purposes but no new content will be added. We encourage everyone interested in neutron scattering to take full advantage of this exciting new resource for our community. Neutronsources.org Data Formats NeXus: Neutron and X-ray Data Format Crystallographic Binary Format (CBF/imgCIF) Hierarchical Data Format (HDF) Data Analysis and Visualization Data Analysis for Neutron Scattering Experiments (DANSE): distributed data analysis project Large Array Manipulation Program (LAMP): IDL-based data analysis and visualization

65

Diffuse Scattering  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Diffuse Scattering Diffuse Scattering * Anticipatory (trick) question: If you have an x-ray or neutron detector looking at a small sample volume, which will scatter more x- rays or neutrons into the detector 1 atom 100 atoms or 1000 atoms? X-ray or neutron beam Answer: Depends! Diffuse Scattering Gene E. Ice Materials Science and Technology Division Oak Ridge National Laboratory, USA National School on Neutron and X-ray Scattering ORNL/SNS June 2011 Presentation concentrates year graduate-level course into 1 hour * Skip mathematical complexities * Expose to range of applications * Develop intuition for length scales * Talk like x-ray/neutron scattering guru - Reciprocal space - Debye Temperature - Laue monotonic - Krivoglaz defects of 1st/2nd kinds! Great for cocktail parties or impressing attractive strangers-

66

Bidirectional-Genetics Platform, a Dual-Purpose Mutagenesis Strategy for Filamentous Fungi  

Science Journals Connector (OSTI)

...insertional mutants. The BiG platform was evaluated using the rice...supporting the utility of this platform for systematic gene function...big advantage of REMI over chemical- or radiation-induced random...Bidirectional-Genetics (BiG) platform. This strategy combines forward...

Jaejin Park; Yong-Hwan Lee

2013-09-20T23:59:59.000Z

67

Solar Energy 74 (2003) 157173 Comparison between ray-tracing simulations and bi-directional  

E-Print Network [OSTI]

Solar Energy 74 (2003) 157­173 Comparison between ray-tracing simulations and bi-Louis Scartezzini a Solar Energy and Building Physics Laboratory LESO-PB, Swiss Federal Institute of Technology EPFL-tracing software. For the first time, an attempt is made to validate detailed bi-directional properties

68

First-time remote sensing of NO2 vertical distributions in an urban street canyon using Topographic Target Light scattering Differential Optical Absorption Spectroscopy (ToTaL-DOAS)  

Science Journals Connector (OSTI)

Topographic Target Light scattering Differential Optical Absorption Spectroscopy (ToTaL-DOAS) measurements were performed in a street canyon in Gwangju, Korea (35°10?51.43?N, 126°52?53.74?E) during a period of 10 days in October 2010. NO2 slant volume mixing ratios (VMRs) at the lowest elevation angle (EL) of 1°, as obtained from ToTaL-DOAS measurements, were validated via comparisons with collocated in situ ground data, showing good agreement within a scatter range of 20% during the entire measurement period, and within a scatter range of 15% when cloudy days were excluded. For the first time, based on inversion calculations using ToTaL-DOAS data, we retrieved NO2 vertical distributions that consist of five layers (from 6 to 118 m) for three measurement days. We obtained generally decreasing NO2 \\{VMRs\\} with altitude, whereas increased NO2 \\{VMRs\\} at two elevated layers (6–19 m and 19–33 m) were observed on 26 and 27 October. We obtained a coefficient of determination (R2) of 0.87 (0.61) between slant \\{VMRs\\} at 1° EL (retrieved NO2 \\{VMRs\\} in the layer from 6 m to 19 m) and in situ data, with the scatter of the correlation being within the 15% (10%) range. The relation between retrieved NO2 \\{VMRs\\} at 6–19 m and slant \\{VMRs\\} at 1° EL yielded an R2 value of 0.97, with the scatter of the correlation being within the 5% range. The results demonstrate that the ToTaL-DOAS technique is a useful tool in identifying the temporal and vertical characteristics of NO2 \\{VMRs\\} in an urban street canyon with a complex geometry.

Hanlim Lee; Myojeong Gu; Young J. Kim; Jungbae Hwang; Ukkyo Jung

2012-01-01T23:59:59.000Z

69

Unidirectionally Invisible Potentials as Local Building Blocks of all Scattering Potentials  

E-Print Network [OSTI]

We give a complete solution of the problem of constructing a scattering potential v(x) that possesses scattering properties of one's choice at an arbitrary prescribed wavenumber. Our solution involves expressing v(x) as the sum of at most six unidirectionally invisible finite-range potentials for which we give explicit formulas. Our results can be employed for designing optical potentials. We discuss its application in modeling threshold lasers, coherent perfect absorbers, and bidirectionally and unidirectionally reflectionless absorbers, amplifiers, and phase shifters.

Ali Mostafazadeh

2014-07-04T23:59:59.000Z

70

A Three-Phase Bidirectional DC-DC Converter for Automotive Applications  

SciTech Connect (OSTI)

This paper presents a three-phase soft-switching, bidirectional dc-dc converter for high-power automotive applications. The converter employs dual three-phase active bridges and operates with a novel asymmetrical but fixed duty cycle for the top and bottom switches of each phase leg. Simulation and experimental data on a 6-kW prototype are included to verify the novel operating and power flow control principles.

Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

2008-01-01T23:59:59.000Z

71

3-D agricultural air quality modeling: Impacts of NH3/H2S gas–phase reactions and bi-directional exchange of NH3  

Science Journals Connector (OSTI)

Abstract Accurately simulating the transport and fate of reduced nitrogen (NHx = ammonia (NH3) + ammonium (NH4+))- and sulfur-containing compounds emitted from agricultural activities represents a major challenge in agricultural air quality modeling. In this study, the Community Multiscale Air Quality (CMAQ) modeling system is further developed and improved by implementing 22 ammonia (NH3)/hydrogen sulfide (H2S) related gas-phase reactions and adjusting a few key parameters (e.g., emission potential) for bi-directional exchange of NH3 fluxes. Several simulations are conducted over the eastern U.S. domain at a 12-km horizontal resolution for January and July 2002 to examine the impacts of those improved treatments on air quality. The 5th generation mesoscale model (MM5) and CMAQ predict an overall satisfactory and consistent performance with previous modeling studies, especially for 2-m temperature, 2-m relative humidity, ozone (O3), and fine particulate matter (PM2.5). High model biases exist for precipitation in July and also dry/wet depositions. The updated model treatments contribute to O3, NHx, and PM2.5 by up to 0.4 ppb, 1.0 ?g m?3, and 1.0 ?g m?3 in January, respectively, and reduce O3 by up to 0.8 ppb and contribute to \\{NHx\\} and PM2.5 by up to 1.2 and 1.1 ?g m?3 in July, respectively. The spatial distributions of O3 in both months and sulfur dioxide (SO2) in January are mainly affected by inline dry deposition velocity calculation. The spatial distributions of SO2 and sulfate (SO42?) in July are affected by both inline dry deposition velocity and NH3/H2S reactions. The variation trends of NH3, NHx, ammonium nitrate (NH4NO3), PM2.5 and total nitrogen (TN) are predominated by bi-directional exchange of NH3 fluxes. Uncertainties of NH3 emission potentials and empirical constants used in the bi-directional exchange scheme may significantly affect the concentrations of \\{NHx\\} and PM2.5, indicating that a more accurate and explicit treatment for those parameters should be considered in the future work.

Kai Wang; Yang Zhang

2014-01-01T23:59:59.000Z

72

Timelike Compton Scattering at Jlab  

SciTech Connect (OSTI)

It is demonstrated, that with exclusive final state, data from electron scattering experiments that are recorded with loose trigger requirements can be used to analyze photoproduction reactions. A preliminary results on Timelike Compton Scattering using the electroproduction data from the CLAS detector at Jefferson Lab are presented. In particular, using final state (pe{sup -}e{sup +}) photoproduction of vector mesons and timelike photon is studied. Angular asymmetries in Timelike Compton Scattering region is compared with model predictions in the framework of Generalized Parton Distribution.

Paremuzyan, Rafayel G. [Institut de Physique Nucleaire, Orsay (France)

2014-01-01T23:59:59.000Z

73

Multiple-scattering effects on incoherent neutron scattering in glasses and viscous liquids  

E-Print Network [OSTI]

Incoherent neutron scattering experiments are simulated for simple dynamic models: a glass (with a smooth distribution of harmonic vibrations) and a viscous liquid (described by schematic mode-coupling equations). In most situations multiple scattering has little influence upon spectral distributions, but it completely distorts the wavenumber-dependent amplitudes. This explains an anomaly observed in recent experiments.

Joachim Wuttke

2000-04-25T23:59:59.000Z

74

Neutron Scattering from Star Polymers in a Matrix of Homopolymers  

Science Journals Connector (OSTI)

Neutron Scattering from Star Polymers in a Matrix of Homopolymers ... Benoit, H. On the effect of Branching and Polydispersity on the Angular Distribution of the Light Scattered by Gaussian Coils. ...

Mehmet Tombako?lu; A. Ziya Akcasu

1997-12-01T23:59:59.000Z

75

System and method for bidirectional flow and controlling fluid flow in a conduit  

DOE Patents [OSTI]

A system for measuring bidirectional flow, including backflow, of fluid in a conduit is disclosed. The system utilizes a structural mechanism to create a pressure differential in the conduit. Pressure sensors are positioned upstream from the mechanism, at the mechanism, and downstream from the mechanism. Data from the pressure sensors are transmitted to a microprocessor or computer, and pressure differential detected between the pressure sensors is then used to calculate the backflow. Control signals may then be generated by the microprocessor or computer to shut off valves located in the conduit, upon the occurrence of backflow, or to control flow, total material dispersed, etc. in the conduit. 3 figs.

Ortiz, M.G.

1999-03-23T23:59:59.000Z

76

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS--I: REGULAR PAPERS, VOL. 60, NO. 5, MAY 2013 1149 Chopper-Stabilized Bidirectional Current  

E-Print Network [OSTI]

-Stabilized Bidirectional Current Acquisition Circuits for Electrochemical Amperometric Biosensors Hamed Mazhab Jafari and Roman Genov Abstract--Two low-noise bidirectional current acquisition cir- cuits for interfacing with electrochemical amperometric biosensor arrays are presented. The first design is a switched

Genov, Roman

77

Giant resonance study by 6li scattering  

E-Print Network [OSTI]

above 35 MeV. Other processes give a large physical background at high excitation energy in ? inelastic scattering, which makes it difficult to extract strength distributions in this range. As an isoscalar projectile (N=Z), 6Li scattering could...

Chen, Xinfeng

2009-05-15T23:59:59.000Z

78

A New Treatment of Rough Surface Scattering  

Science Journals Connector (OSTI)

...1996 research-article A New Treatment of Rough Surface Scattering C. Macaskill P...narrow beam at a randomly rough surface where the height distribution...is Gaussian. The field at the surface is assumed to satisfy a Dirichlet...

1996-01-01T23:59:59.000Z

79

Nonadiabatic reactive scattering in atom+triatom systems: Nascent rovibronic distributions in F+H{sub 2}O{yields}HF+OH  

SciTech Connect (OSTI)

Crossed supersonic jet studies of F+H{sub 2}O{yields}HF+OH({sup 2}{Pi}{sub 3/2},{sup 2}{Pi}{sub 1/2}) have been performed under low density, single collision conditions at E{sub com}=6(2) kcal/mol, yielding rotational, vibrational, and spin-orbit state distributions in the nascent OH product by laser induced fluorescence methods. The lowest reaction barriers on the ground and first excited electronic surfaces are {Delta}E{approx_equal}4 kcal/mol and {Delta}E{approx_equal}25 kcal/mol, correlating with OH({sup 2}{Pi}{sub 3/2}) and OH({sup 2}{Pi}{sub 1/2}), respectively. Although only reactions on the ground state potential are Born-Oppenheimer allowed at the experimental collision energies, both ground and excited spin-orbit OH products are observed in a {sup 2}{Pi}{sub 3/2}:{sup 2}{Pi}{sub 1/2}=69(1)%:31(1)% branching ratio. This indicates the presence of strong nonadiabatic surface hopping interactions, in agreement with previous results for the F+D{sub 2}O{yields}DF+OD reaction. Despite clear differences in the rotational distributions between F+H{sub 2}O and F+D{sub 2}O isotopic reactions, the overall electronic branching into spin-orbit manifolds is nearly identical for both OH and OD products. Furthermore, when plotted versus total electronic+rotational energy, the nascent OH and OD populations each lie on single curves, with pronounced kinks in the Boltzmann plots suggestive of microscopic branching in the reaction dynamics. Such an equivalence of electronic and rotational energy release in the OH/OD products is consistent with predominantly nonadiabatic processes taking place in the immediate post-transition state region rather than asymptotically in the exit channel.

Ziemkiewicz, Michael; Nesbitt, David J. [JILA, National Institute of Standards and Technology, University of Colorado, Boulder, Colorado 80309-0440 (United States) and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440 (United States)

2009-08-07T23:59:59.000Z

80

Molecular-beam scattering  

SciTech Connect (OSTI)

The molecular-beam technique has been used in three different experimental arrangements to study a wide range of inter-atomic and molecular forces. Chapter 1 reports results of a low-energy (0.2 kcal/mole) elastic-scattering study of the He-Ar pair potential. The purpose of the study was to accurately characterize the shape of the potential in the well region, by scattering slow He atoms produced by expanding a mixture of He in N/sub 2/ from a cooled nozzle. Chapter 2 contains measurements of the vibrational predissociation spectra and product translational energy for clusters of water, benzene, and ammonia. The experiments show that most of the product energy remains in the internal molecular motions. Chapter 3 presents measurements of the reaction Na + HCl ..-->.. NaCl + H at collision energies of 5.38 and 19.4 kcal/mole. This is the first study to resolve both scattering angle and velocity for the reaction of a short lived (16 nsec) electronic excited state. Descriptions are given of computer programs written to analyze molecular-beam expansions to extract information characterizing their velocity distributions, and to calculate accurate laboratory elastic-scattering differential cross sections accounting for the finite apparatus resolution. Experimental results which attempted to determine the efficiency of optically pumping the Li(2/sup 2/P/sub 3/2/) and Na(3/sup 2/P/sub 3/2/) excited states are given. A simple three-level model for predicting the steady-state fraction of atoms in the excited state is included.

Vernon, M.F.

1983-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Scattering of Fast Neutrons by Magnesium  

Science Journals Connector (OSTI)

Angular distributions for the scattering of fast neutrons by magnesium have been obtained for incident neutron energies of 2.0, 3.0, 4.0, and 5.0 Mev. The results for the elastic scattering have been compared with optical model calculations. The results for the inelastic scattering have been compared with calculations based on Hauser-Feshbach theory, and with direct interaction predictions. Over the range of conditions investigated, compound nucleus formation appears to be the dominant mechanism for the inelastic scattering.

D. B. Thomson; L. Cranberg; J. S. Levin

1962-03-15T23:59:59.000Z

82

Scattering apodizer for laser beams  

DOE Patents [OSTI]

A method is disclosed for apodizing a laser beam to smooth out the production of diffraction peaks due to optical discontinuities in the path of the laser beam, such method comprising introduction of a pattern of scattering elements for reducing the peak intensity in the region of such optical discontinuities, such pattern having smoothly tapering boundaries in which the distribution density of the scattering elements is tapered gradually to produce small gradients in the distribution density, such pattern of scattering elements being effective to reduce and smooth out the diffraction effects which would otherwise be produced. The apodizer pattern may be produced by selectively blasting a surface of a transparent member with fine abrasive particles to produce a multitude of minute pits. In one embodiment, a scattering apodizer pattern is employed to overcome diffraction patterns in a multiple element crystal array for harmonic conversion of a laser beam. The interstices and the supporting grid between the crystal elements are obscured by the gradually tapered apodizer pattern of scattering elements.

Summers, Mark A. (Livermore, CA); Hagen, Wilhelm F. (Livermore, CA); Boyd, Robert D. (Livermore, CA)

1985-01-01T23:59:59.000Z

83

Scattering apodizer for laser beams  

DOE Patents [OSTI]

A method is disclosed for apodizing a laser beam to smooth out the production of diffraction peaks due to optical discontinuities in the path of the laser beam, such method comprising introduction of a pattern of scattering elements for reducing the peak intensity in the region of such optical discontinuities, such pattern having smoothly tapering boundaries in which the distribution density of the scattering elements is tapered gradually to produce small gradients in the distribution density, such pattern of scattering elements being effective to reduce and smooth out the diffraction effects which would otherwise be produced. The apodizer pattern may be produced by selectively blasting a surface of a transparent member with fine abrasive particles to produce a multitude of minute pits. In one embodiment, a scattering apodizer pattern is employed to overcome diffraction patterns in a multiple element crystal array for harmonic conversion of a laser beam. The interstices and the supporting grid between the crystal elements are obscured by the gradually tapered apodizer pattern of scattering elements.

Summers, M.A.; Hagen, W.F.; Boyd, R.D.

1984-01-01T23:59:59.000Z

84

Structural characterization of Green River oil-shale at high-pressure using pair distribution function analysis and small angle x-ray scattering.  

SciTech Connect (OSTI)

The compression behavior of a silicate-rich oil shale from the Green River formation in the pressure range 0.0-2.4 GPa was studied using in situ high pressure X-ray pair distribution function (PDF) measurements for the sample contained within a Paris-Edinburgh cell. The real-space local structural information in the PDF, G(r), was used to evaluate the compressibility of the oil shale. Specifically, the pressure-induced reduction in the medium- to long-range atom distances (6-20 {angstrom}) yielded an average sample compressibility corresponding to a bulk modulus of ca. 61-67 GPa. A structural model consisting of a three phase mixture of the principal crystalline oil shale components (quartz, albite and Illite) provided a good fit to the ambient pressure PDF data (R 30.7%). Indeed the features in the PDF beyond 6 {angstrom}, were similarly well fit by a single phase model of the highest symmetry, highly crystalline quartz component.

Locke, D. R.; Chupas, P. J.; Chapman, K. W.; Pugmire, R. J.; Winans, R. E.; Univ. of Utah

2008-01-01T23:59:59.000Z

85

Neutron Scattering Facilities  

Science Journals Connector (OSTI)

The past history, present performance and future prospects for neutron scattering facilities will be discussed. Special features of neutron scattering techniques applicable to biological problems will be ... . Th...

D. L. Price

1996-01-01T23:59:59.000Z

86

Fuel cycle analysis in a thorium fueled reactor using bidirectional fuel movement : correction to report MIT-2073-1, MITNE-51  

E-Print Network [OSTI]

This report corrects an error discovered in the code used in the study "Fuel Cycle Analysis in a Thorium Fueled Reactor Using Bidirectional Fuel Movement," MIT-2073-1, MITNE-51. The results of the correction show considerable ...

Stephen, James D.

1965-01-01T23:59:59.000Z

87

Time resolved side scatter diagnostics at NOVA  

SciTech Connect (OSTI)

Side scattering of the radiation during the interaction of a laser beam with the long scale length plasma in hohlraum is a difficult problem of relevance to the viability of ICF. It is important to measure the absolute amount of the laser side scatter as well as the angular distribution of that scatter. The OSA diagnostics has been implemented on NOVA to measure these quantities. We have implemented a fiber-optically coupled streak camera to measure the temporally and angularly resolved side scatter radiation at 351 nm at 9 different angles. Filtered PIN diodes were positioned at 31 various angles in the E-field planed and B-field plane of the incident probe beam to sample and measure the scattered radiation at the 351 nm wavelength of the probe. The diode data was used to calibrate the Brillouin power received by the 9 strategically located fiber optic channels. This presentation will describe the OSA and associated diagnostics.

Kyrala, G.A.; Evans, S.C.; Jimerson, J.R.; Fernandez, J.C.

1996-06-01T23:59:59.000Z

88

Neutron scattering studies of carbon nanotubes  

Science Journals Connector (OSTI)

We report on neutron scattering studies of single wall carbon nanotubes (SWNT). Small angle scattering was used to investigate the structure of SWNT suspensions. Diffraction data were compared to calculations on finite-size bundles of SWNT in order to estimate the distribution of tube diameters. Lastly we present an inelastic neutron scattering study of the density of phonon states in SWNT. In the frequency range of intramolecular modes the measured spectrum is found to be in good agreement with that calculated on an isolated (10 10) nanotube.

E. Anglaret; S. Rols; J. L. Sauvajol

1999-01-01T23:59:59.000Z

89

Proton-Neutron Scattering  

Science Journals Connector (OSTI)

Using Glauber multiple-scattering theory, the missing-mass spectrum for protons scattered off a deuterium target is computed. The relatively clean separation of the single- and double-scattering peaks offers the possibility of determining the high-energy proton-neutron differential cross section.

N. Straumann and C. Wilkin

1970-03-02T23:59:59.000Z

90

Intermediate Scattering Function in Slow Neutron Scattering  

Science Journals Connector (OSTI)

The conditions under which the so-called intermediate scattering function occurring in the theory of slow neutron scattering and in the theory of the Mössbauer effect can be written in the form exp[-?2?(t)] have been explicitly stated; the intermediate scattering function is then factorizable into two parts; the part referred to in the paper as the displacement part gives on Fourier transformation a real space-time function which, quite unambiguously, has the meaning usually attributed to the Van Hove Gs(x, t) function; the other part arises out of the nucleus recoiling against the neutron. It is shown that for systems in thermal equilibrium, the recoil part can be expressed in terms of the displacement part. This relation enables one to take care of the recoil part in case a classical approximation is made for the dynamics of the scattering system.

A. Rahman

1963-05-15T23:59:59.000Z

91

Simultaneous Neutron Scattering and Raman Scattering  

Science Journals Connector (OSTI)

The capability to make simultaneous neutron and Raman scattering measurements at temperatures between 1.5 and 450 K has been developed. The samples to be investigated are attached to...

Adams, Mark A; Parker, Stewart F; Fernandez-Alonso, Felix; Cutler, David J; Hodges, Christopher; King, Andrew

2009-01-01T23:59:59.000Z

92

Dense Plasma X-ray Scattering: Methods and Applications  

SciTech Connect (OSTI)

We have developed accurate x-ray scattering techniques to measure the physical properties of dense plasmas. Temperature and density are inferred from inelastic x-ray scattering data whose interpretation is model-independent for low to moderately coupled systems. Specifically, the spectral shape of the non-collective Compton scattering spectrum directly reflects the electron velocity distribution. In partially Fermi degenerate systems that have been investigated experimentally in laser shock-compressed beryllium, the Compton scattering spectrum provides the Fermi energy and hence the electron density. We show that forward scattering spectra that observe collective plasmon oscillations yield densities in agreement with Compton scattering. In addition, electron temperatures inferred from the dispersion of the plasmon feature are consistent with the ion temperature sensitive elastic scattering feature. Hence, theoretical models of the static ion-ion structure factor and consequently the equation of state of dense matter can be directly tested.

Glenzer, S H; Lee, H J; Davis, P; Doppner, T; Falcone, R W; Fortmann, C; Hammel, B A; Kritcher, A L; Landen, O L; Lee, R W; Munro, D H; Redmer, R; Weber, S

2009-08-19T23:59:59.000Z

93

Total Neutron Scattering in Vitreous Silica  

Science Journals Connector (OSTI)

The structure of Corning superpure vitreous silica glass has been investigated with neutrons. A new method of analysis using variable neutron wavelengths and the measurement of total scattering cross sections from transmission experiments is developed and the results are compared with those from differential x-ray scattering. The total neutron scattering method permits a simple and direct structure analysis with resolution apparently superior to x-rays. The preliminary results compare well in a first approximation analysis with the basic structure model of Warren and others and in addition the neutron-determined atomic radial distribution curve exhibits some finer details than the x-ray results. Thermal inelastic scattering of neutrons was corrected for in an approximate way.

R. J. Breen; R. M. Delaney; P. J. Persiani; A. H. Weber

1957-01-15T23:59:59.000Z

94

Electromagnetic Form Factors of the Nucleon and Compton Scattering  

E-Print Network [OSTI]

We review the experimental and theoretical status of elastic electron scattering and elastic low-energy photon scattering (with both real and virtual photons) from the nucleon. As a consequence of new experimental facilities and new theoretical insights, these subjects are advancing with unprecedented precision. These reactions provide many important insights into the spatial distributions and correlations of quarks in the nucleon.

Charles Earl Hyde-Wright; Kees de Jager

2005-07-01T23:59:59.000Z

95

Neutron Scattering Facilities 1982  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

NEUTRON SOURCES NEUTRON SOURCES Types of Sources U.S. Sources Available for Users Plans for the Future The Neutron Scattering Society of America (NSSA) SNS/ANL School on Neutron and x-Ray Scattering, June 2011 Jim Rhyne Lujan Neutron Scattering Center Los Alamos National Lab. What do we need to do neutron scattering? * Neutron Source - produces neutrons * Diffractometer or Spectrometer - Allows neutrons to interact with sample - Sorts out discrete wavelengths by monochromator (reactor) or by time of flight (pulse source) - Detectors pick up neutrons scattered from sample * Analysis methods to determine material properties * Brain power to interpret results Sources of neutrons for scattering * Nuclear Reactor - Neutrons produced from fission of 235 U - Fission spectrum neutrons

96

Scattering of Skyrmions  

E-Print Network [OSTI]

In this paper, we present a detailed study of Skyrmion-Skyrmion scattering for two $B=1$ Skyrmions in the attractive channel where we observe two different scattering regimes. For large separation, the scattering can be approximated as interacting dipoles. We give a qualitative estimate when this approximation breaks down. For small separations we observe an additional short-range repulsion which is qualitatively similar to monopole scattering. We also observe the interesting effect of "rotation without rotating" whereby two Skyrmions, whose orientations remain constant while well-separated, change their orientation after scattering. We can explain this effect by following preimages through the scattering process, thereby measuring which part of an in-coming Skyrmion forms part of an out-going Skyrmion. This leads to a new way of visualising Skyrmions. Furthermore, we consider spinning Skyrmions and find interesting trajectories.

David Foster; Steffen Krusch

2014-12-30T23:59:59.000Z

97

Muon-proton Scattering  

E-Print Network [OSTI]

A recent proposal to measure the proton form factor by means of muon-proton scattering will use muons which are not ultrarelativistic (and also not nonrelativistic). The usual equations describing the scattering cross section use the approximation that the scattered lepton (usually an electron) is ultrarelativistic, with v/c approximately equal to 1. Here the cross section is calculated for all values of the energy. It agrees with the standard result in the appropriate limit.

E. Borie

2012-07-24T23:59:59.000Z

98

A system for differential neutron scattering experiments in the energy range from 0.5 to 20 MeV  

E-Print Network [OSTI]

A system for differential neutron scattering experiments in the energy range from 0.5 to 20 MeV F 2010 Accepted 15 April 2010 Available online 27 May 2010 Keywords: Scattering Neutron Benchmark dependent scattered neutron distributions. Scattering measurements were performed on carbon and molybdenum

Danon, Yaron

99

Environment scattering in GADRAS.  

SciTech Connect (OSTI)

Radiation transport calculations were performed to compute the angular tallies for scattered gamma-rays as a function of distance, height, and environment. Green's Functions were then used to encapsulate the results a reusable transformation function. The calculations represent the transport of photons throughout scattering surfaces that surround sources and detectors, such as the ground and walls. Utilization of these calculations in GADRAS (Gamma Detector Response and Analysis Software) enables accurate computation of environmental scattering for a variety of environments and source configurations. This capability, which agrees well with numerous experimental benchmark measurements, is now deployed with GADRAS Version 18.2 as the basis for the computation of scattered radiation.

Thoreson, Gregory G.; Mitchell, Dean James; Theisen, Lisa Anne; Harding, Lee T.

2013-09-01T23:59:59.000Z

100

Scattering Solar Thermal Concentrators  

Broader source: Energy.gov (indexed) [DOE]

is a rendering of a scattering solar concentrator. Light collected by a cylindrical Fresnel lens is focused within a curved glass "guide" sheet, where it is redirected into...

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Concepts in spin echo small-angle neutron scattering  

Science Journals Connector (OSTI)

Two-dimensional spin echo small-angle neutron scattering experiments are proposed for the direct measurement of the vector-length distribution function. Interpretation of the correlation function from one-dimensional experiments is also presented.

Zhao, J.

2001-09-25T23:59:59.000Z

102

Goniometric measurement of power scattered from wind driven water surfaces  

Science Journals Connector (OSTI)

A recently constructed 11?ft 3?axis semiautomatic underwater goniometer has made possible precision measurement of acoustic power scattered from the statistically stationary wind driven water surface at Yale. Measurements have been made over 180° of azimuth and at several grazing angles. These measurements have been corrected for beam patterns and pulse shape to give a scattering cross section for the surfaces and geometries studied. The results of these measurements indicate that current mathematical models of the scattering process are not able to predict spatial distribution of scattered power in all cases.

J. G. Zornig

1976-01-01T23:59:59.000Z

103

Plural Scattering of 20-kev Electrons in Aluminum  

Science Journals Connector (OSTI)

The angular and energy distribution of 20-kev electrons, scattered at very small angles (<10-2 rad) by transmission through aluminum foils, are compared with the theory of plural inelastic scattering, under the following assumptions: (a) The probability of elastic scattering at very small angles is negligibly small in comparison with the probability of inelastic scattering. (b) Inelastic scattering occurs predominantly through sharply defined "characteristic" energy losses, whose number follows a Poisson statistical distribution. (c) The angular distribution in each loss follows a simple law: ?(?)?(?E2+?2)-1. (d) The cumulative angular distribution from plural inelastic scattering is obtained by repeated "folding" of ?(?) with the angular spread of the incident beam. The angular distribution of zero-loss electrons is found to be substantially independent of the foil thickness; the normalized angular distributions of the first- and second-loss peaks are accurately fitted by the "folding" calculation; Poisson statistics gives a good approximation to the observed numbers of energy losses. The value of ? for five observations on foils of thicknesses 650-2580 A is approximately 810 A, independent of thickness; systematic errors in the method of observation may render this value up to 20% higher than the mean free path corresponding to the total cross section.

L. Marton; J. Arol Simpson; H. A. Fowler; N. Swanson

1962-04-01T23:59:59.000Z

104

Thermal neutron scattering  

Science Journals Connector (OSTI)

... and liquids. They have just the right wavelength for atomic physics; and, as nuclear scattering takes place effectively at a point, one can use the ... takes place effectively at a point, one can use the scattered intensity to disentangle the motion of atoms. The momentum transfer dependence of ithe ...

D. V. Bugg

1979-06-14T23:59:59.000Z

105

Neutron Scattering by Liquid Neon  

Science Journals Connector (OSTI)

A theory for neutron scattering by a semiclassical system, which is appropriate for liquid neon, is described. The theory is based on a generalized mean-field approximation involving the polarization potential and the screened response function, similarly to what has been done previously for argon and helium. The screened response function is assumed to be a sum of Gaussian functions weighted by the momentum-distribution function. The polarization potential and the width of the Gaussians are determined by the zeroth and third moments of the scattering law. The momentum distribution has the Maxwell—Boltzmann form, but includes quantum corrections to order ?2. The quantum-mechanical zero-point energy is found to increase the kinetic energy per particle to a value of about 30% greater than the classical equipartition value. Calculations have been done for wave-vector transfers in the range 0.75-5.5 times the wave vector at the principal maximum in the static-structure factor, and the theoretical line shapes have been folded with the resolution function for the experiments of Buyers et al. Comparison of the position of the maximum, full width at half-maximum, and line shapes with the experimental results gives good agreement.

W. C. Kerr and K. S. Singwi

1973-03-01T23:59:59.000Z

106

Neutron-Proton Scattering at 156$\\,\\pm \\,$3 MeV  

Science Journals Connector (OSTI)

8 July 1952 research-article Neutron-Proton Scattering at 156 3 MeV T. C. Randle A. E. Taylor E. Wood The angular distribution for neutron-proton scattering at 156 3 MeV has been determined for centre-of-mass scattering angles between...

1952-01-01T23:59:59.000Z

107

Nonrelativistic Description of Nucleon-Nucleus Scattering  

SciTech Connect (OSTI)

Within the three-dimensional semiclassical approximation, an analytic expression is obtained for the amplitude of proton-nucleus scattering at intermediate energies of incident protons. The method for deriving this amplitude is based on the use of the high-energy approximation with distorted waves. In view of the short-range character of proton-nucleon interaction, the process of proton-nucleus scattering is represented as a series of single scattering events occurring on each individual nucleon. With the aid of the proposed mathematical formalism, a recursion relation is derived that makes it possible to express the nuclear form factor obtained within the distorted-wave method in terms of the sum of an infinite Born series. Parameters that characterize the distributions of protons and neutrons in the spherical nuclei {sup 40}Ca, {sup 48}Ca, {sup 90}Zr, and {sup 208}Pb and which include the width of the surface layer of nucleons and the root-mean-square radii of the proton-, neutron-, and nucleon-density distributions are determined from an analysis of the measured cross sections for the elastic scattering of 1-GeV protons, a modified Fermi function being employed for the nucleon-density distribution.

Mirabutalybov, M.M. [Azerbaijan State Petroleum Academy, pr. Azadlyg 20, Baku, 370010 (Azerbaijan)

2004-12-01T23:59:59.000Z

108

Measurement of Lattice Vibrations in Vanadium by Neutron Scattering  

Science Journals Connector (OSTI)

The energy spectrum of slow neutrons inelastically scattered by vanadium metal has been measured by the time-of-flight technique. The neutrons gain energy by absorbing quanta of lattice vibration energy (phonons). As the nuclear scattering amplitude of vanadium is incoherent, the energy distribution of scattered neutrons is directly related to the frequency distribution of lattice vibrations. The measured neutron energy spectrum, as well as the derived frequency distribution, shows a clearly resolved double peak. This structure, which is distinctly different from the simple Debye distribution, but expected on the basis of detailed calculations, has heretofore not been amenable to direct measurement. The measured frequency distribution is compared with calculations for a body-centered cubic lattice by the Born-von Kármán theory and qualitative agreement is obtained. A more exact comparison awaits measurement of the elastic constants of vanadium.

C. M. Eisenhauer; I. Pelah; D. J. Hughes; H. Palevsky

1958-02-15T23:59:59.000Z

109

Inelastic Neutron Scattering Instrumentation  

Science Journals Connector (OSTI)

Abstract Inelastic neutron scattering spectroscopy spans an enormous energy range, which is equivalent to a wide range of timescales. It is convenient to divide the whole energy range into three sectors, while recognising that there is significant overlap between them. In the lowest energy range, ± 10 meV the applications are principally quasielastic scattering and tunneling spectroscopy. The second range, 0–1000 meV covers the regions of vibrational spectroscopy and magnetic excitations. The highest range above 1000 meV is the province of neutron Compton scattering. The instrumentation used in each of these energy regimes is described.

S.F. Parker

2014-01-01T23:59:59.000Z

110

Scattering Solar Thermal Concentrators  

Broader source: Energy.gov [DOE]

"This fact sheet describes a scattering solar thermal concentrators project awarded under the DOE's 2012 SunShot Concentrating Solar Power R&D award program. The team, led by the Pennsylvania State University, is working to demonstrate a new, scattering-based approach to concentrating sunlight that aims to improve the overall performance and reliability of the collector field. The research team aims to show that scattering solar thermal collectors are capable of achieving optical performance equal to state-of-the-art parabolic trough systems, but with the added benefits of immunity to wind-load tracking error, more efficient land use, and utilization of stationary receivers."

111

HS: Scattering --June 24, 1997 TIME--DEPENDENT SCATTERING THEORY  

E-Print Network [OSTI]

completeness, which was stated precisely in the early days of scattering theory [Jauch], [Hack]. The challenge

112

Scattering of Slow Neutrons  

Science Journals Connector (OSTI)

1 September 1937 research-article Scattering of Slow Neutrons M. Goldhaber G. H. Briggs The Royal Society is collaborating with JSTOR to digitize, preserve, and extend access to Proceedings...

1937-01-01T23:59:59.000Z

113

Compton Scattering of  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Compton Scattering of Picosecond Electron and CO2 beams T. Hirose (TMU) @BNL user meeting, Jan. 31, 2002 JapanUS cooperation in high energy physics (Supported by JSPS from 1998)...

114

Neutron-Neutron Scattering at Low Energies  

Science Journals Connector (OSTI)

This paper investigates the information contained in a neutron-neutron scattering experiment at low energies which could be performed by colliding beams coming from an underground nuclear explosion. The significance of such an experiment is discussed from the point of view of a check on charge symmetry and charge independence, and it is found that because of the electromagnetic complications in proton-proton scattering, and because of the proton-neutron mass difference, the knowledge of neutron-neutron scattering would be of considerable value. The functional form of the experimental data which is most convenient for analysis and the approximate relative magnitude of the terms is investigated, and it is concluded that for the kind of experiment which is envisaged (measuring cross sections to 10% from 20 keV to 2 MeV) only two parameters should be kept in the effective-range expansion. The connection between the number and distribution of energies at which the cross section is measured and the error on the individual measurements, on the one hand, and the accuracy of the effective-range parameters deduced from the experiments, on the other, is given explicitly and is found also to depend on the absolute magnitude of the scattering length. The results show that ten 10% measurements, suitably distributed between 20 keV and 2 MeV, can determine the sign of the scattering length to four standard deviations, the magnitude of the effective range to 50-70%, and the magnitude of the scattering length to about 3%. Finally, the relationship between the variation of the effective-range parameters and the corresponding variation in the parameters of the scattering potential is studied, and it is found that, while this relationship is strongly shape-dependent, a small change in the potential parameters, in any case, results in a large change in the scattering length, but a small one in the effective range. Numerical relationships show that, even in the worst case, the variation in the scattering length is about eight times the variation in the potential parameter. It is concluded that a 10% experiment at 20 energies between 20 keV and 2 MeV would be able to get information on the potential parameters sufficiently accurately so that charge-dependent or charge-symmetry violating effects could be detected.

Michael J. Moravcsik

1964-11-09T23:59:59.000Z

115

Lightweight PV Inverters: Dual Bi-Directional IGBTs Modules Enables Breakthrough PV Inverter Using Current Modulation Topology  

SciTech Connect (OSTI)

Solar ADEPT Project: PV inverters convert DC power generated by modules into usable AC power. IPC’s initial 30kW 94lb. PV inverter reduces the weight of comparable 30kW PV inverters by 90%—reducing the cost of materials, manufacturing, shipping, and installation. With ARPA-E support, new bi-directional silicon power switches will be developed, commercialized, and utilized in IPC’s next-generation PV inverter. With these components, IPC will produce 100kW inverters that weight less than 100lb., reducing the weight of conventional 3,000lb. 100kW inverters by more than 95%. The new power switches will cut IPC’s $/W manufacturing cost in half, as well as further reduce indirect shipping and installation costs.

None

2012-01-30T23:59:59.000Z

116

Distributed Algorithms Distributed Transactions  

E-Print Network [OSTI]

Algorithms© Gero Mühl 8 Concurrency Control serial RC (ReCoverable) ACA (Avoiding Cascading Aborts) ST (StricDistributed Algorithms Distributed Transactions PD Dr.-Ing. Gero Mühl Kommunikations- und Betriebssysteme Fakultät für Elektrotechnik u. Informatik Technische Universität Berlin #12;Distributed Algorithms

Wichmann, Felix

117

Fracture Properties From Seismic Scattering  

E-Print Network [OSTI]

Fractures scatter seismic energy and this energy can be analyzed to provide information about fracture

Burns, Daniel R.

2007-01-01T23:59:59.000Z

118

Scattering from Materials BRENT FULTZ  

E-Print Network [OSTI]

by scattering methods using x-rays, electrons, neutrons, and -rays. Coherent elastic scattering, for example by inelastic neutron scattering to understand the reasons for differences in vibrational entropy of different and local distortions around impurity atoms. The field of inelastic neutron scattering is a broad one

119

Nonlinear X-ray Compton Scattering  

E-Print Network [OSTI]

X-ray scattering is a weak linear probe of matter. It is primarily sensitive to the position of electrons and their momentum distribution. Elastic X-ray scattering forms the basis of atomic structural determination while inelastic Compton scattering is often used as a spectroscopic probe of both single-particle excitations and collective modes. X-ray free-electron lasers (XFELs) are unique tools for studying matter on its natural time and length scales due to their bright and coherent ultrashort pulses. However, in the focus of an XFEL the assumption of a weak linear probe breaks down, and nonlinear light-matter interactions can become ubiquitous. The field can be sufficiently high that even non-resonant multiphoton interactions at hard X-rays wavelengths become relevant. Here we report the observation of one of the most fundamental nonlinear X-ray-matter interactions, the simultaneous Compton scattering of two identical photons producing a single photon at nearly twice the photon energy. We measure scattered...

Fuchs, Matthias; Chen, Jian; Ghimire, Shambhu; Shwartz, Sharon; Kozina, Michael; Jiang, Mason; Henighan, Thomas; Bray, Crystal; Ndabashimiye, Georges; Bucksbaum, P H; Feng, Yiping; Herrmann, Sven; Carini, Gabriella; Pines, Jack; Hart, Philip; Kenney, Christopher; Guillet, Serge; Boutet, Sebastien; Williams, Garth; Messerschmidt, Marc; Seibert, Marvin; Moeller, Stefan; Hastings, Jerome B; Reis, David A

2015-01-01T23:59:59.000Z

120

Quasiclassical Theory of Neutron Scattering  

Science Journals Connector (OSTI)

A Wigner representation is used for expressing the thermal average occurring in the Van Hove formalism for slow-neutron scattering from macroscopic systems. For quadratic and lower-degree potentials, results in closed form may be obtained, and in general, an asymptotic series expansion in powers of ? is still possible for the incoherent part of the differential cross section for quasiclassical systems. The lead term of this asymptotic expansion results in an expression relating the cross section to a four-dimensional Fourier inversion of the classical space-time distribution Gsc(r, t), and hence to the classical motions of the atoms in the scattering system. Correction terms of O(?2) have been obtained explicitly and found to be small for systems at ordinary temperatures. It is shown that (at least to order ?2) the results obey the constraint of detailed balance and satisfy the Placzek moments. It is also shown that because of the contact nature of the Fermi pseudopotential, the exact classical limit (??0) for any system is the ideal-gas result. In principle, the results can be extended to all orders of ?2. No similar asymptotic expansion appears to exist, however, for the coherent cross section. The analysis is then used for deriving other existing prescriptions and for examining their implications and range of validity.

M. Rosenbaum and P. F. Zweifel

1965-01-25T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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121

Scattering of Fast Neutrons by Helium  

Science Journals Connector (OSTI)

Measurements have been made of the angular distribution of helium recoils for incident neutrons of energies from 0.6 to 1.6 Mev. The distribution curves also permit estimates of the total cross section in this energy range. The results confirm the existence of a cross-section peak of about 6.8×10-24 cm2 around 1 Mev and indicate, under the assumption of s- and p-wave scattering only, that the peak is double. But preliminary attempts to fit the data to Bloch's detailed theory of s- and p-scattering with a split p-level have not been successful, and the sign of the postulated splitting is not established.

T. A. Hall and P. G. Koontz

1947-08-01T23:59:59.000Z

122

Dust Measurement With Thomson Scattering In FTU  

SciTech Connect (OSTI)

The size distribution of dust particles present in FTU after disruptions has been evaluated in the range 0.05 {mu}m-0.1 {mu}m using the Thomson scattering system. Rayleigh approximation has been used to estimate the dust size. The distribution, although the radii considered do not differ more than an order of magnitude, behave like a power law. The laser energy density far exceed that necessary to vaporize, at least partially, the particles. This can affect the previous estimate of the particle sizes, and suggests that the effective radii might be larger than the estimated values. A preliminary analysis on the broad band signal is presented.

Giovannozzi, E.; Castaldo, C.; Maddaluno, G.; Rydzy, A. [Associazione EURATOM-ENEA sulla fusione, CR Frascati, c.p. 65, 00044 Frascati, RM (Italy); Ratynskaia, S. [Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden)

2008-03-12T23:59:59.000Z

123

Neutron Scattering Conference Archive  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Conference Archive Conference Archive A new portal for neutron scattering has just been established at neutronsources.org. The information contained here in the Neutron Scattering Web has been transferred to the new site. We will leave the current content here for archival purposes but no new content will be added. We encourage everyone interested in neutron scattering to take full advantage of this exciting new resource for our community. Neutronsources.org 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 2000 June 12-14, 2000 Workshop on "New Opportunities for Better User Group Software (NOBUGS III)" Location Daresbury Laboratory, Cheshire, UK Contact Mark Enderby, Daresbury Laboratory Email M.J.Enderby@dl.ac.uk URL http://nobugs.dl.ac.uk/

124

Defect Scattering in Graphene  

Science Journals Connector (OSTI)

Irradiation of graphene on SiO2 by 500 eV Ne and He ions creates defects that cause intervalley scattering as is evident from a significant Raman D band intensity. The defect scattering gives a conductivity proportional to charge carrier density, with mobility decreasing as the inverse of the ion dose. The mobility decrease is 4 times larger than for a similar concentration of singly charged impurities. The minimum conductivity decreases proportional to the mobility to values lower than 4e2/?h, the minimum theoretical value for graphene free of intervalley scattering. Defected graphene shows a diverging resistivity at low temperature, indicating insulating behavior. The results are best explained by ion-induced formation of lattice defects that result in midgap states.

Jian-Hao Chen; W. G. Cullen; C. Jang; M. S. Fuhrer; E. D. Williams

2009-06-12T23:59:59.000Z

125

Magnetic neutron scattering (invited)  

Science Journals Connector (OSTI)

The application of neutron scattering techniques to magnetic problems is reviewed. We will first discuss diffraction techniques used to solve magnetic structures as well as to measure magnetic form factors order parameters critical phenomena and the scattering from low?dimensional systems. We will also discuss inelastic scattering techniques including polarized beam methods utilized to determine the spin dynamics of various materials. Information will be provided about the types of spectrometers available at the user?oriented national facilities located at Argonne National Laboratory Brookhaven National Laboratory Los Alamos National Laboratory The National Institute of Standards and Technology and Oak Ridge National Laboratory as well as the spectrometers at the Missouri University Research Reactor.

J. W. Lynn

1994-01-01T23:59:59.000Z

126

MAGNETIC NEUTRON SCATTERING  

SciTech Connect (OSTI)

Much of our understanding of the atomic-scale magnetic structure and the dynamical properties of solids and liquids was gained from neutron-scattering studies. Elastic and inelastic neutron spectroscopy provided physicists with an unprecedented, detailed access to spin structures, magnetic-excitation spectra, soft-modes and critical dynamics at magnetic-phase transitions, which is unrivaled by other experimental techniques. Because the neutron has no electric charge, it is an ideal weakly interacting and highly penetrating probe of matter's inner structure and dynamics. Unlike techniques using photon electric fields or charged particles (e.g., electrons, muons) that significantly modify the local electronic environment, neutron spectroscopy allows determination of a material's intrinsic, unperturbed physical properties. The method is not sensitive to extraneous charges, electric fields, and the imperfection of surface layers. Because the neutron is a highly penetrating and non-destructive probe, neutron spectroscopy can probe the microscopic properties of bulk materials (not just their surface layers) and study samples embedded in complex environments, such as cryostats, magnets, and pressure cells, which are essential for understanding the physical origins of magnetic phenomena. Neutron scattering is arguably the most powerful and versatile experimental tool for studying the microscopic properties of the magnetic materials. The magnitude of the cross-section of the neutron magnetic scattering is similar to the cross-section of nuclear scattering by short-range nuclear forces, and is large enough to provide measurable scattering by the ordered magnetic structures and electron spin fluctuations. In the half-a-century or so that has passed since neutron beams with sufficient intensity for scattering applications became available with the advent of the nuclear reactors, they have became indispensable tools for studying a variety of important areas of modern science, ranging from large-scale structures and dynamics of polymers and biological systems, to electronic properties of today's technological materials. Neutron scattering developed into a vast field, encompassing many different experimental techniques aimed at exploring different aspects of matter's atomic structure and dynamics. Modern magnetic neutron scattering includes several specialized techniques designed for specific studies and/or particular classes of materials. Among these are magnetic reflectometry aimed at investigating surfaces, interfaces, and multilayers, small-angle scattering for the large-scale structures, such as a vortex lattice in a superconductor, and neutron spin-echo spectroscopy for glasses and polymers. Each of these techniques and many others offer exciting opportunities for examining magnetism and warrant extensive reviews, but the aim of this chapter is not to survey how different neutron-scattering methods are used to examine magnetic properties of different materials. Here, we concentrate on reviewing the basics of the magnetic neutron scattering, and on the recent developments in applying one of the oldest methods, the triple axis spectroscopy, that still is among the most extensively used ones. The developments discussed here are new and have not been coherently reviewed. Chapter 2 of this book reviews magnetic small-angle scattering, and modern techniques of neutron magnetic reflectometry are discussed in Chapter 3.

ZALIZNYAK,I.A.; LEE,S.H.

2004-07-30T23:59:59.000Z

127

ANALYTIC EXPRESSIONS FOR THE LIGHT-SCATTERING CROSS SECTION  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ANALYTIC ANALYTIC EXPRESSIONS FOR THE LIGHT-SCATTERING CROSS SECTION AND ÅNGSTRÖM EXPONENT OF AN AEROSOL Ernie R. Lewis Brookhaven National Laboratory, Upton, NY 11933 elewis@bnl.gov BACKGROUND For an aerosol consisting of spherical particles with size distribution of number concentration dN(r)/dr and real index of refraction m (thus no absorption), the light-scattering coefficient σ sp

128

A New Model of Centrality Measure based on Bidirectional Power Flow for  

E-Print Network [OSTI]

power flow based model to evaluate the criticality in smart grid environment. Change in direction of smart grid includes various generation options, primarily in the distribution side ­ near consumers. Engagement of customers with the energy management systems is the most lucrative part of smart grid from

Pota, Himanshu Roy

129

Neutron Scattering Tutorials | Neutron Science | ORNL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Neutron Scattering Tutorials SHARE Neutron Scattering Tutorials The following lectures were presented at the 2011 and 2010 National School on Neutron & X-Ray Scattering. This...

130

Low?frequency sound radiation and scattering from bubble clouds.  

Science Journals Connector (OSTI)

Recent experimental evidence has shown that when wave breaking occurs low?frequency (LF?200 Hz) sound is produced and LF scatter has a different characteristic than expected from rough sea surface scattering. These effects have been attributed to the bubbles produced during wave breaking which are convected to depth by the breaking turbulence vorticity and Langmuir circulation as observed by Thorpe [S. Thorpe Oceanic White Caps edited by E. Monahan and G. MacNiocaill (Reidel Boston 1986) pp. 57–58]. While the radiation and scatteringcharacteristics at frequencies greater than 1 kHz are explained by incoherent scatter from the observed bubble size and space distributions the lower frequency phenomena are not easily explained. However if bubble plumes and clouds produced in the wave breaking have appreciable volume fractions (?10?5) then LF sound radiation and scattering can be explained by classical theories. This paper reviews the scattering and radiation from bubbleclouds in water as a function of volume fraction. When the cloud is compact coherent and collective scatter are shown to occur. The natural frequency of radiation is shown to be described by a modified Minnaert result while the backscatter target strength is described by the first?order volume mode. These analytical results agree with experimental sound radiation and scatter measurements. Finally the collective radiation of bubble plumes and clouds is discussed as a possible explanation of the observed ocean low?frequency scattering and radiation phenomena. [Work sponsored by ONR 11250A and NUSC IR.

William M. Carey

1992-01-01T23:59:59.000Z

131

Neutron Scattering Methods in Chemistry  

Science Journals Connector (OSTI)

Before going into details of the scattering of neutrons in condensed phases, some of this elementary particle should be recalled, as these characteristics play a central role in the scattering process.

2003-01-01T23:59:59.000Z

132

Thermodynamics of irregular scattering  

Science Journals Connector (OSTI)

It is pointed out that scaling (multifractal) properties of chaotic repellers underlying irregular scattering in two-degrees-of-freedom systems can be deduced by measuring simple length scales generated hierarchically along a straight line taken far away from the interaction region, or on the Poincaré plane, and analyzing them in the spirit of the thermodynamic formalism. The method is easier to apply than a periodic orbit analysis.

Zoltán Kovács and Tamás Tél

1990-04-02T23:59:59.000Z

133

Using bi-directional communications in a market-based resource allocation system  

DOE Patents [OSTI]

Disclosed herein are representative embodiments of methods, apparatus, and systems for distributing a resource (such as electricity) using a resource allocation system. In one exemplary embodiment, a plurality of requests for electricity are received from a plurality of end-use consumers. The requests indicate a requested quantity of electricity and a consumer-requested index value indicative of a maximum price a respective end-use consumer will pay for the requested quantity of electricity. A plurality of offers for supplying electricity are received from a plurality of resource suppliers. The offers indicate an offered quantity of electricity and a supplier-requested index value indicative of a minimum price for which a respective supplier will produce the offered quantity of electricity. A dispatched index value is computed at which electricity is to be supplied based at least in part on the consumer-requested index values and the supplier-requested index values.

Chassin, David P; Pratt, Robert G

2014-04-01T23:59:59.000Z

134

New information on parton distributions  

Science Journals Connector (OSTI)

New data on structure functions from deep-inelastic scattering provide new information on parton distributions, particularly in the 0.01u¯ at small x. With the inclusion of the latest deep-inelastic data we find ?s(MZ)=0.111-0.005+0.004. We also show how W, Z, and Drell-Yan production at p¯p colliders can give information on parton distributions.

A. D. Martin; W. J. Stirling; R. G. Roberts

1993-02-01T23:59:59.000Z

135

A New Polyethylene Scattering Law Determined Using Inelastic Neutron Scattering  

SciTech Connect (OSTI)

Monte Carlo neutron transport codes such as MCNP rely on accurate data for nuclear physics cross-sections to produce accurate results. At low energy, this takes the form of scattering laws based on the dynamic structure factor, S (Q, E). High density polyethylene (HDPE) is frequently employed as a neutron moderator at both high and low temperatures, however the only cross-sections available are for T =300 K, and the evaluation has not been updated in quite some time. In this paper we describe inelastic neutron scattering measurements on HDPE at 5 and 300 K which are used to improve the scattering law for HDPE. We describe the experimental methods, review some of the past HDPE scattering laws, and compare computations using these models to the measured S (Q, E). The total cross-section is compared to available data, and the treatment of the carbon secondary scatterer as a free gas is assessed. We also discuss the use of the measurement itself as a scattering law via the 1 phonon approximation. We show that a scattering law computed using a more detailed model for the Generalized Density of States (GDOS) compares more favorably to this experiment, suggesting that inelastic neutron scattering can play an important role in both the development and validation of new scattering laws for Monte Carlo work.

Lavelle, Christopher M [ORNL; Liu, C [Oak Ridge National Laboratory (ORNL); Stone, Matthew B [ORNL

2013-01-01T23:59:59.000Z

136

Raman scattering in crystals  

SciTech Connect (OSTI)

A tutorial presentation is given of Raman scattering in crystals. The physical concepts are emphasized rather than the detailed mathematical formalism. Starting with an introduction to the concepts of phonons and conservation laws, the effects of photon-phonon interactions are presented. This interaction concept is shown for a simple cubic crystal and is extended to a uniaxial crystal. The correlation table method is used for determining the number and symmetry of the Raman active modes. Finally, examples are given to illustrate the relative ease of using this group theoretical method and the predictions are compared with measured Raman spectra. 37 refs., 17 figs., 6 tabs.

Edwards, D.F.

1988-09-30T23:59:59.000Z

137

Volume Scattering of Acoustic Waves in the N. E. Pacific Ocean  

Science Journals Connector (OSTI)

Two types of scattering strength measurements have been obtained in the N. E. Pacific Ocean in deep water approximately 100 NM west of the entrance to the Strait of Juan de Fuca. The first type is obtained using surface venting explosive charges with the listening hydrophone suspended near the surface (i.e. depth <50 ft) to measure the backscattered acoustic energy. Levels of the intensity time curves so observed yield the scattering strength integrated to the depth corresponding to the time coordinate on the decay curve i.e. ? z?d z? O m r ?(z)?dz while the decay rates yield information on the scattering distribution in the medium. The second type of scattering measurement obtained is the scattering strength profile. Such profiles are obtained using near monostatic fired charge and receiver placed at various depths. Observation of the close?in scattered returns permits adequate resolution to plot scattering profiles through most layers [i.e. mv (z) z=0+d ]. Both sets of measurements show the diurnal migration of the scattering layers as well as the frequency characteristics. However the technique of measuring the scattering strength profile is the more direct and yields a better picture of layer distributions and the depth dependence of the scattering spectra.

J. A. Scrimger; R. G. Turner

1969-01-01T23:59:59.000Z

138

Plane wave solution for elastic wave scattering by a heterogeneous fracture  

E-Print Network [OSTI]

Plane wave solution for elastic wave scattering by a heterogeneous fracture Seiji Nakagawa,a) Kurt for computing the three-dimensional scattering of propagating elastic waves by a planar fracture with heterogeneous fracture compliance distribution is presented. This method is based upon the spatial Fourier

Santos, Juan

139

Lossy Electric Transmission Line Soft Fault Diagnosis: an Inverse Scattering Approach  

E-Print Network [OSTI]

1 Lossy Electric Transmission Line Soft Fault Diagnosis: an Inverse Scattering Approach Huaibin transmission lines is studied through the inverse scattering approach. The considered soft faults are modeled as continuous spatial variations of distributed characteristic parameters of transmission lines. The diagnosis

Paris-Sud XI, Université de

140

Deeply Virtual Compton Scattering off the neutron  

E-Print Network [OSTI]

The present experiment exploits the interference between the Deeply Virtual Compton Scattering (DVCS) and the Bethe-Heitler processes to extract the imaginary part of DVCS amplitudes on the neutron and on the deuteron from the helicity-dependent D$({\\vec e},e'\\gamma)X$ cross section measured at $Q^2$=1.9 GeV$^2$ and $x_B$=0.36. We extract a linear combination of generalized parton distributions (GPDs) particularly sensitive to $E_q$, the least constrained GPD. A model dependent constraint on the contribution of the up and down quarks to the nucleon spin is deduced.

M. Mazouz; A. Camsonne; C. Muñoz Camacho; for the Jefferson Lab Hall A collaboration

2007-09-04T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Inter-slice bidirectional registration-based segmentation of the prostate gland in MR and CT image sequences  

SciTech Connect (OSTI)

Purpose: Accurate segmentation and volume estimation of the prostate gland in magnetic resonance (MR) and computed tomography (CT) images are necessary steps in diagnosis, treatment, and monitoring of prostate cancer. This paper presents an algorithm for the prostate gland volume estimation based on the semiautomated segmentation of individual slices in T2-weighted MR and CT image sequences. Methods: The proposedInter-Slice Bidirectional Registration-based Segmentation (iBRS) algorithm relies on interslice image registration of volume data to segment the prostate gland without the use of an anatomical atlas. It requires the user to mark only three slices in a given volume dataset, i.e., the first, middle, and last slices. Next, the proposed algorithm uses a registration algorithm to autosegment the remaining slices. We conducted comprehensive experiments to measure the performance of the proposed algorithm using three registration methods (i.e., rigid, affine, and nonrigid techniques). Results: The results with the proposed technique were compared with manual marking using prostate MR and CT images from 117 patients. Manual marking was performed by an expert user for all 117 patients. The median accuracies for individual slices measured using the Dice similarity coefficient (DSC) were 92% and 91% for MR and CT images, respectively. The iBRS algorithm was also evaluated regarding user variability, which confirmed that the algorithm was robust to interuser variability when marking the prostate gland. Conclusions: The proposed algorithm exploits the interslice data redundancy of the images in a volume dataset of MR and CT images and eliminates the need for an atlas, minimizing the computational cost while producing highly accurate results which are robust to interuser variability.

Khalvati, Farzad, E-mail: farzad.khalvati@uwaterloo.ca; Tizhoosh, Hamid R. [Department of Systems Design Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)] [Department of Systems Design Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Salmanpour, Aryan; Rahnamayan, Shahryar [Department of Engineering and Applied Science, University of Ontario Institute of Technology, Oshawa, Ontario L1H 7K4 (Canada)] [Department of Engineering and Applied Science, University of Ontario Institute of Technology, Oshawa, Ontario L1H 7K4 (Canada); Rodrigues, George [Department of Radiation Oncology, London Regional Cancer Program, London, Ontario N6C 2R6, Canada and Department of Epidemiology/Biostatistics, University of Western Ontario, London, Ontario N6A 3K7 (Canada)] [Department of Radiation Oncology, London Regional Cancer Program, London, Ontario N6C 2R6, Canada and Department of Epidemiology/Biostatistics, University of Western Ontario, London, Ontario N6A 3K7 (Canada)

2013-12-15T23:59:59.000Z

142

Simulated impact of sensor field of view and distance on field measurements of bidirectional reflectance factors for row crops  

Science Journals Connector (OSTI)

Abstract It is well established that a natural surface exhibits anisotropic reflectance properties that depend on the characteristics of the surface. Spectral measurements of the bidirectional reflectance factor (BRF) at ground level provide us a method to capture the directional characteristics of the observed surface. Various spectro-radiometers with different field of views (FOVs) were used under different mounting conditions to measure crop reflectance. The impact and uncertainty of sensor FOV and distance from the target have rarely been considered. The issue can be compounded with the characteristic reflectance of heterogeneous row crops. Because of the difficulty of accurately obtaining field measurements of crop reflectance under natural environments, a method of computer simulation was proposed to study the impact of sensor FOV and distance on field measured BRFs. A Monte Carlo model was built to combine the photon spread method and the weight reduction concept to develop the weighted photon spread (WPS) model to simulate radiation transfer in architecturally realistic canopies. Comparisons of the Monte Carlo model with both field BRF measurements and the RAMI Online Model Checker (ROMC) showed good agreement. \\{BRFs\\} were then simulated for a range of sensor FOV and distance combinations and compared with the reference values (distance at infinity) for two typical row canopy scenes. Sensors with a finite FOV and distance from the target approximate the reflectance anisotropy and yield average values over FOV. Moreover, the perspective projection of the sensor causes a proportional distortion in the sensor FOV from the ideal directional observations. Though such factors inducing the measurement error exist, it was found that the BRF can be obtained with a tolerable bias on ground level with a proper combination of sensor FOV and distance, except for the hotspot direction and the directions around it. Recommendations for the choice of sensor FOV and distance are also made to reduce the bias from the real angular signatures in field BRF measurement for row crops.

Feng Zhao; Yuguang Li; Xu Dai; Wout Verhoef; Yiqing Guo; Hong Shang; Xingfa Gu; Yanbo Huang; Tao Yu; Jianxi Huang

2015-01-01T23:59:59.000Z

143

Neutron-Proton Scattering near 180° at 93 Mev  

Science Journals Connector (OSTI)

A measurement has been made with neutrons of 93-Mev effective energy of the angular distribution of n-p scattering near 180° in the center-of-mass system. The results show that the magnitude of the cross section approaches the 180° point smoothly, without any sudden increase.

W. Selove; K. Strauch; F. Titus

1953-11-01T23:59:59.000Z

144

Scattering of Gravitational Radiation by a Schwarzschild Black-hole  

Science Journals Connector (OSTI)

... To begin with, a spherically symmetric mass distribution is assumed to have collapsed into its Schwarzschild surface in the infinitely remote past. The scattering of gravitational waves by this configuration ... Retaining the notation of the authors and concentrating on the odd-parity waves, the perturbed Schwarzschild exterior line element in the Regge-Wheeler canonical gauge can be written as

C. V. VISHVESHWARA

1970-08-29T23:59:59.000Z

145

Electron, Photon, and Positron Scattering Dynamics of Complex Molecular Targets  

E-Print Network [OSTI]

from ground state Cl2 and Pt in the 1S and 3D states in the multichannel configuration-interaction (MCCI) approximation originally developed for photoionization for scattering up to 10 eV. Photoionization cross sections and angular distributions...

Carey, Ralph

2012-07-16T23:59:59.000Z

146

LANSCE | Lujan Neutron Scattering Center  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Lujan Center Data Management Lujan Neutron Scattering Center Logo The Lujan Center within LANSCE utilizes a pulsed source and has a complement of 15 instruments. It maintains a...

147

LANSCE School on Neutron Scattering:  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

11 th LANSCE School on Neutron Scattering: Materials at the Mesoscale Lujan Center Los Alamos Neutron Science Center Los Alamos National Laboratory lansce.lanl.govneutronschool...

148

Scattering of Neutrons by Lead  

Science Journals Connector (OSTI)

... THE University of Cambridge cyclotron and neutron velocity selector have been used for studying the ... velocity selector have been used for studying the scattering of ...

R. LATHAM; J. M. CASSELS

1948-02-21T23:59:59.000Z

149

The electron-spin-nuclear-spin interaction studied by polarized neutron scattering  

Science Journals Connector (OSTI)

The directional properties of electron-proton spin interaction in an external magnetic field give rise to an anisotropic distribution of the intensity of polarized neutron scattering from dynamically polarized protons of radical molecules in solution.

Stuhrmann, H.B.

2007-11-01T23:59:59.000Z

150

Book review Light Scattering Reviews 4: Single Light Scattering and  

E-Print Network [OSTI]

-monograph on the use of space-time Green functions in the description of the diffusive radiation transport in active equation of the radiative transfer theory in the classical style of the ``Soviet'' school of radiativeBook review Light Scattering Reviews 4: Single Light Scattering and Radiative Transfer, A

151

The CJ12 parton distributions  

SciTech Connect (OSTI)

Three new sets of next-to-leading order parton distribution functions (PDFs) are presented, determined by global fits to a wide variety of data for hard scattering processes. The analysis includes target mass and higher twist corrections needed for the description of deep-inelastic scattering data at large x and low Q^2, and nuclear corrections for deuterium targets. The PDF sets correspond to three different models for the nuclear effects, and provide a more realistic uncertainty range for the d quark PDF compared with previous fits. Applications to weak boson production at colliders are also discussed.

Accardi, Alberto [JLAB; Owens, Jeff F. [Florida State U.

2013-07-01T23:59:59.000Z

152

Electricity Distribution  

Science Journals Connector (OSTI)

High voltage (HV) distribution grids have nominal voltages of up ... the grid that connects distribution to the transmission substations and also supplies large industrial customers requiri...

Tomás Gómez

2013-01-01T23:59:59.000Z

153

Light scattering for aerogel characterization  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

for aerogel characterization for aerogel characterization Title Light scattering for aerogel characterization Publication Type Journal Article Year of Publication 1998 Authors Hunt, Arlon J. Journal Journal of Non-Crystalline Solids Volume 225 Pagination 303-306 Keywords aerogel, light scattering, microstructure Abstract Light scattering is a useful tool to evaluate aerogel clarity, study its structure, pore size, mechanical strain, and examine the modes of sol-gel evolution that determine its microstructure. Ultraviolet-visible transmission spectroscopy can be used to study the wavelength dependent scattering to readily compare aerogels of differing origins, thickness, and to evaluate effects of residual contaminants. Infrared reflectance measurements can be used to determine the effective real and imaginary indices of refraction of porous aerogel materials for material property and radiant heat transfer studies. Measurements of scattering at a fixed angle can be used for quality control, to evaluate sources of scattering, and study inhomogeneities. Measurement of the Mueller matrix (describing the 16-element angle-dependent transformation of intensity and polarization of incident to scattered light) provides information about the anisotropy, large pore fraction, induced stresses, microstructure and inhomogeneities in the aerogel. The time evolution of scattering before and after gel formation gives information.

154

Elastic Electron Scattering from Tritium and Helium-3  

DOE R&D Accomplishments [OSTI]

The mirror nuclei of tritium and helium-3 have been studied by the method of elastic electron scattering. Absolute cross sections have been measured for incident electron energies in the range 110 - 690 MeV at scattering angles lying between 40 degrees and 135 degrees in this energy range. The data have been interpreted in a straightforward manner and form factors are given for the distributions of charge and magnetic moment in the two nuclei over a range of four-momentum transfer squared 1.0 - 8.0 F{sup -2}. Model-independent radii of the charge and magnetic moment distributions are given and an attempt is made to deduce form factors describing the spatial distribution of the protons in tritium and helium-3.

Collard, H.; Hofstadter, R.; Hughes, E. B.; Johansson, A.; Yearian, M. R.; Day, R. B.; Wagner, R. T.

1964-10-00T23:59:59.000Z

155

Inelastic neutron scattering study on bioprotectant systems  

Science Journals Connector (OSTI)

...22 December 2005 Inelastic neutron scattering study on bioprotectant systems...UK We collected inelastic neutron scattering (INS) spectra of homologous...vibrational properties|neutron scattering| 1. Introduction In recent...

2005-01-01T23:59:59.000Z

156

Neutron scattering from adsorbed polymer layers  

Science Journals Connector (OSTI)

Neutron scattering from adsorbed polymer layers ... Small-Angle Neutron Scattering Study of Cyclic Poly(ethylene glycol) Adsorption on Colloidal Particles ... Small-Angle Neutron Scattering Study of Cyclic Poly(ethylene glycol) Adsorption on Colloidal Particles ...

Terence Cosgrove; Timothy G. Heath; Keith Ryan; Trevor L. Crowley

1987-11-01T23:59:59.000Z

157

Inelastic Neutron Scattering from Glass Formers  

Science Journals Connector (OSTI)

......research-article Articles Inelastic Neutron Scattering from Glass Formers U. Buchenau...transition. Coherent inelastic neutron scattering data indicate a mixture of...Supplement No. 126, 1997 Inelastic Neutron Scattering from Glass Formers U. BUCHENAU......

U. Buchenau

1997-01-01T23:59:59.000Z

158

Quasiclassical Approximation for Slow Neutron Scattering  

Science Journals Connector (OSTI)

......Approximation for Slow Neutron Scattering Takeo Nishigori Department...formula for the differential scattering cross section of a slow neutron is derived along the line...of Spherical Rotors and Neutron Scattering Juichiro Hama and Tuto......

Takeo Nishigori

1970-06-01T23:59:59.000Z

159

Neutron scattering in concrete and wood  

Science Journals Connector (OSTI)

......Article Computational techniques Neutron scattering in concrete and wood A. Facure...library were used to simulate the neutron scattering in barriers of conventional...of the barrier thickness on neutron scattering factors is also being studied......

A. Facure; A. X. Silva; R. C. Falcão; V. R. Crispim

2006-09-01T23:59:59.000Z

160

Neutron Scattering in ORNL'S Calibration Facility  

Science Journals Connector (OSTI)

......Dosimetry Article Neutron Scattering in ORNL'S Calibration...C. Francis Room scattering corrections for several common neutron detectors in a new...and enclosed room scattering situations are compared...good. A personnel neutron spectrometer was......

J.C. Liu; C.S. Sims; W.H. Casson; H. Murakami; C. Francis

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Energy distribution of Compton-scattered gamma rays  

E-Print Network [OSTI]

of the experimental peaks, and is shown in Figs. 15, 17, 19, 21, and 22. The FNHM of these curves can be measured and the broaden- ing due to the Doppler effect calculated. The equation used is where D is the broadening due to the Doppler effect, E... of this corrected curve was found to fit a Gaussian curve of dispersion 6. 6 keV. The FWHM of the Gaussian corresponding to this is 15. 4 keV, From thi. s, the broadening due to the Doppler effect is found to be 10. 2-1 keV, + The uncertainty in the Doppler...

Moreland, Richard Wayne

2012-06-07T23:59:59.000Z

162

What Does a Scattering Pattern Tell US?  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Space sample light image Image Space lens Angular Space Q 4p sin(q) l Fourier Transform Scattering Pattern Fourier Transform Phase Problem Scattering Pattern Fourier...

163

Microwave scattering from laser spark in air  

SciTech Connect (OSTI)

In this paper, microwave Mie scattering from a laser-induced plasma in atmospheric air is computed. It shows that the scattered microwave transitions from coherent Rayleigh scattering to Mie scattering based on the relative transparency of the laser-induced plasma at the microwave frequency. The microwave penetration in the plasma alters from total transparency to partial shielding due to the sharp increase of the electron number density within the avalanche ionization phase. The transition from Rayleigh scattering to Mie scattering is verified by both the temporal evolution of the scattered microwave and the homogeneity of polar scattering plots.

Sawyer, Jordan; Zhang Zhili [Mechanical, Aerospace and Biomedical Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States); Shneider, Mikhail N. [Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States)

2012-09-15T23:59:59.000Z

164

Search for: "neutron scattering" | DOE PAGES  

Office of Scientific and Technical Information (OSTI)

neutron scattering" Find + Advanced Search Advanced Search All Fields: "neutron scattering" Title: Full Text: Bibliographic Data: Creator Author: Name Name ORCID Type: All...

165

Neutron Scattering User Program | Neutron Science | ORNL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

User Program SHARE Neutron Scattering Can Benefit Your Research Neutron scattering has applications in almost every technical and scientific field, from biology and chemistry to...

166

Nonlinear forward scattering of light in opaque media  

Science Journals Connector (OSTI)

Because of disorder, the intensity of light diffusively propagating in a weakly absorbing opaque medium fluctuates randomly from one point to the another. If the light intensity is large enough the third-order nonlinearity, in combination with intensity fluctuations of the pump light, gives rise to an angular scattering of the probe wave. We have shown that because of long-range correlations of the intensity fluctuations the angular distribution of the probe wave incident on a thin slab and scattered in the forward direction has a narrow peak at small scattering angles. The shape of this peak depends on the boundary conditions on the surface of the slab. If the surface of the slab strongly reflects the pump photons the peak becomes narrower and much more intense than in the case of a weak reflection.

A. G. Mal’shukov and G. D. Mahan

1998-04-01T23:59:59.000Z

167

The scattering of muons in low Z materials  

E-Print Network [OSTI]

This paper presents the measurement of the scattering of 172 MeV/c muons in assorted materials, including liquid hydrogen, motivated by the need to understand ionisation cooling for muon acceleration. Data are compared with predictions from the Geant 4 simulation code and this simulation is used to deconvolute detector effects. The scattering distributions obtained are compared with the Moliere theory of multiple scattering and, in the case of liquid hydrogen, with ELMS. With the exception of ELMS, none of the models are found to provide a good description of the data. The results suggest that ionisation cooling will work better than would be predicted by Geant 4.7.0p01.

Attwood, D; Benveniste, S; Bogacz, A; Bull, S; Cline, D; Curtis-Rouse, M; Edgecock, T R; Ellis, M; Fernow, R; Fukui, Y; Gruber, P; Holmes, S; Ishida, K; Jamdagni, A; Lee, K; Lidbury, J; Long, K; Marshall, G M; Matsuda, Y; McKigney, E; McMahon, T; Murray, W J; Nagamine, K; Nakamura, S; Norton, P; Peach, Kenneth J; Pischalnikov, Y; Savage, P; Wilson, J

2006-01-01T23:59:59.000Z

168

Theory of Raman scattering in coupled electron-phonon systems  

Science Journals Connector (OSTI)

The Raman spectrum is calculated for a coupled conduction-electron–phonon system in the zero-momentum-transfer limit. The Raman scattering is due to electron-hole excitations and phonons as well. The phonons of those branches that contribute to the electron self-energy and the correction of the electron-phonon vertex are assumed to have flat energy dispersion (the Einstein phonons). The effect of electron-impurity scattering is also incorporated. Both the electron-phonon interaction and the electron-impurity interaction cause the fluctuation of the electron distribution between different parts of the Fermi surface, which results in overdamped zero-sound modes of various symmetries. The scattering cross section is obtained by solving the Bethe-Salpeter equation. The spectrum shows a lower threshold at the smallest Einstein phonon energy when only the electron-phonon interaction is taken into consideration. When impurities are also taken into consideration, the threshold disappears.

K. Itai

1992-01-01T23:59:59.000Z

169

Modifying molecule-surface scattering by ultrashort laser pulses  

SciTech Connect (OSTI)

In recent years it has become possible to align molecules in free space using ultrashort laser pulses. Here we explore two schemes for controlling molecule-surface scattering processes and which are based on laser-induced molecular alignment. In the first scheme, a single ultrashort nonresonant laser pulse is applied to a molecular beam hitting the surface. This pulse modifies the angular distribution of the incident molecules and causes the scattered molecules to rotate with a preferred sense of rotation (clockwise or counterclockwise). In the second scheme, two properly delayed laser pulses are applied to a molecular beam composed of two chemically close molecular species (isotopes, or nuclear-spin isomers). As the result of the double-pulse excitation, these species are selectively scattered to different angles after the collision with the surface. These effects may provide new means for the analysis and separation of molecular mixtures.

Khodorkovsky, Yuri; Averbukh, Ilya Sh. [Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100 (Israel); Manson, J. R. [Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634 (United States)

2011-11-15T23:59:59.000Z

170

Low-Angle Neutron Scattering  

Science Journals Connector (OSTI)

A set of techniques that can be used to find the size of a particle in solution or to find the size or spacing of internal regions that can be distinguished by different neutron scattering power, such as the prot...

Jan W. Gooch

2011-01-01T23:59:59.000Z

171

Neutron-Neutron Scattering Length  

Science Journals Connector (OSTI)

The final-state interaction of the two neutrons from the reaction ?-+d?2n+? has a pronounced and distinctive effect on the momentum spectrum of the outgoing particles. In particular, the neutron spectrum is sharply peaked in the neighborhood of 2 Mev, with a shape that is quite sensitive to the strength of the nn interaction. In the region of this peak, the relative neutron-neutron momentum is so small that the nn interaction is completely characterized by its scattering length. Hence it is proposed that a measurement of the shape of the neutron spectrum from this reaction may provide a convenient means of measuring the neutron-neutron scattering length. Neutron spectra are calculated in an impulse approximation, for several assumed values of the scattering length. It appears from their shapes that, in this way, present neutron-detection techniques should be capable of determining the scattering length to within 25%.

Kirk W. McVoy

1961-03-01T23:59:59.000Z

172

Neutron Scattering Methods in Chemistry  

Science Journals Connector (OSTI)

Starting with basic properties of the neutron, this chapter reviews the most important neutron scattering methods that provide valuable information for a ... wide, from standard methods of crystallography to neutron

L. Pusztai

2011-01-01T23:59:59.000Z

173

Posters Radiation Singularities, Multiple Scattering  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

mean C 1 0.75 and Levy index 1.35 (as empirically observed) and apply to it the Radiative Transfer Equation in the perfect scattering case. We have analytical and numerical...

174

Hadronic scattering of charmed mesons  

E-Print Network [OSTI]

The scattering cross sections of charm mesons with hadrons such as the pion, rho meson, and nucleon are studied in an effective Lagrangian. In heavy ion collisions, rescattering of produced charm mesons by hadrons affects the invariant mass spectra...

Lin, ZW; Ko, Che Ming; Zhang, B.

2000-01-01T23:59:59.000Z

175

Scattering of Neutrons by Protons  

Science Journals Connector (OSTI)

... IT is known that hydrogen shows a large scattering cross-section for slow ... cross-section for slow neutrons. On the usual assumption that the forces between proton and ...

M. GOLDHABER

1936-05-16T23:59:59.000Z

176

Polarized lepton-nucleon scattering  

SciTech Connect (OSTI)

Deep inelastic polarized lepton-nucleon scattering is reviewed in three lectures. The first lecture covers the polarized deep inelastic scattering formalism and foundational theoretical work. The second lecture describes the nucleon spin structure function experiments that have been performed up through 1993. The third lecture discusses implication of the results and future experiments aimed at high-precision measurements of the nucleon spin structure functions.

Hughes, E.

1994-02-01T23:59:59.000Z

177

Neutron scattering at high pressure  

Science Journals Connector (OSTI)

Neutron scattering spectra at pressures up to 30 kilobar in the temperature range 300–4 K have been obtained with a compact clamped type apparatus. The pressure cell geometry by allowing the detection of neutronsscattered in a plane makes it compatible with operation on crystal spectrometers both for elastic and inelastic scattering. The instrument is light (4.5 kg) and easy to move. An external diameter of 68 mm makes the pressure cell adaptable to standard cryostats or furnaces.

D. Bloch; J. Paureau; J. Voiron; G. Parisot

1976-01-01T23:59:59.000Z

178

Scattering of Protons by Deuterons  

Science Journals Connector (OSTI)

Utilizing a scattering chamber based upon the successful design used by Herb, Kerst, Parkinson, and Plain (HKPP) in the measurement of proton-proton scattering, experimental data on the scattering of protons by deuterons have been obtained. The incident protons were accelerated by the 3.5-Mev Wisconsin generator ("long tank") which was used by the Manhattan Project at Los Alamos, New Mexico. The geometry, and the current and pressure measurements were checked by comparing the measurements of proton-proton scattering at 2.1 Mev with the work of HKPP. Results on proton-deuteron scattering at 0.825, 1.51, 2.08, 2.53, 3.00, and 3.49 Mev were obtained. The absolute cross sections per unit solid angle show the presence at all energies studied of higher order waves. A minimum in the scattering is observed near 90° at the low energies; the minimum shifts to larger angles with increasing energy. The cross sections at all angles decrease with increasing energy but the ratio of the cross section at 150° to the minimum increases gradually from 2.3 at 1.51 Mev to 3.0 at 3.49 Mev. The present results at 825 kev do not show the large anomaly found by Tuve, Heydenburg, and Hafstad at 830 kev.

R. Sherr; J. M. Blair; H. R. Kratz; C. L. Bailey; R. F. Taschek

1947-10-15T23:59:59.000Z

179

In situ resonant Raman scattering and reversible photoinduced structural change in YBa{sub 2}Cu{sub 3}O{sub 6+x}  

SciTech Connect (OSTI)

We report on bidirectional photoswitching associated with the CuO chains in oxygen-deficient YBa{sub 2}Cu{sub 3}O{sub 6+x} single crystals. By varying the wavelength of light polarized along the CuO chains, the material can be reversibly switched between two metastable states characterized by the existence or absence of a specific Raman scattering resonance. A comparison of the spectral efficiencies for this photoswitching with analogous data for the persistent photoconductivity and photoconductivity quenching effects suggests that the two phenomena have the same microscopic origin. We argue that the effects are due to photoinduced Cu-O charge-transfer excitations, which destabilize chains of different length depending on wavelength, and promote the growth of thermally inaccessible oxygen ordering configurations.

Osada, Minoru; Kaell, Mikael; Baeckstroem, Joakim; Kakihana, Masato; Andersen, Niels Hessel; Boerjesson, Lars [Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Department of Applied Physics, Chalmers University of Technology, Goeteborg S412-96 (Sweden); Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Materials Research Department, Risoe National Laboratory, DK-4000 Roskilde (Denmark); Department of Applied Physics, Chalmers University of Technology, Goeteborg S412-96 (Sweden)

2005-06-01T23:59:59.000Z

180

Mapping from quasi-elastic scattering to fusion reactions  

E-Print Network [OSTI]

The fusion barrier distribution has provided a nice representation for the channel coupling effects on heavy-ion fusion reactions at energies around the Coulomb barrier. Here we discuss how one can extract the same representation using the so called sum-of-differences (SOD) method with quasi-elastic scattering cross sections. In contrast to the conventional quasi-elastic barrier distribution, the SOD barrier distribution has an advantage in that it can be applied both to non-symmetric and symmetric systems. It is also the case that the correspondence to the fusion barrier distribution is much better than the quasi-elastic barrier distribution. We demonstrate its usefulness by studying $^{16}$O+$^{144}$Sm, $^{58}$Ni+$^{58}$Ni, and $^{12}$C+$^{12}$C systems.

K. Hagino; N. Rowley

2014-03-06T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Integrated, Automated Distributed Generation Technologies Demonstration  

SciTech Connect (OSTI)

The purpose of the NETL Project was to develop a diverse combination of distributed renewable generation technologies and controls and demonstrate how the renewable generation could help manage substation peak demand at the ATK Promontory plant site. The Promontory plant site is located in the northwestern Utah desert approximately 25 miles west of Brigham City, Utah. The plant encompasses 20,000 acres and has over 500 buildings. The ATK Promontory plant primarily manufactures solid propellant rocket motors for both commercial and government launch systems. The original project objectives focused on distributed generation; a 100 kW (kilowatt) wind turbine, a 100 kW new technology waste heat generation unit, a 500 kW energy storage system, and an intelligent system-wide automation system to monitor and control the renewable energy devices then release the stored energy during the peak demand time. The original goal was to reduce peak demand from the electrical utility company, Rocky Mountain Power (RMP), by 3.4%. For a period of time we also sought to integrate our energy storage requirements with a flywheel storage system (500 kW) proposed for the Promontory/RMP Substation. Ultimately the flywheel storage system could not meet our project timetable, so the storage requirement was switched to a battery storage system (300 kW.) A secondary objective was to design/install a bi-directional customer/utility gateway application for real-time visibility and communications between RMP, and ATK. This objective was not achieved because of technical issues with RMP, ATK Information Technology Department’s stringent requirements based on being a rocket motor manufacturing facility, and budget constraints. Of the original objectives, the following were achieved: • Installation of a 100 kW wind turbine. • Installation of a 300 kW battery storage system. • Integrated control system installed to offset electrical demand by releasing stored energy from renewable sources during peak hours of the day. Control system also monitors the wind turbine and battery storage system health, power output, and issues critical alarms. Of the original objectives, the following were not achieved: • 100 kW new technology waste heat generation unit. • Bi-directional customer/utility gateway for real time visibility and communications between RMP and ATK. • 3.4% reduction in peak demand. 1.7% reduction in peak demand was realized instead.

Jensen, Kevin

2014-09-30T23:59:59.000Z

182

RisR1125(EN) Neutron Scattering  

E-Print Network [OSTI]

Risø­R­1125(EN) Neutron Scattering Studies of Modulated Magnetic Structures Steen Aagaard Sørensen investigations of the magnetic systems DyFe4Al8 and MnSi by neutron scattering and in the former case also by X and the correlations between the scattering entities of the sample. The theoretical framework of neutron scattering

183

Charm quark and D^* cross sections in deeply inelastic scattering at DESY HERA  

E-Print Network [OSTI]

A next-to-leading order Monte Carlo program for the calculation of heavy quark cross sections in deeply inelastic scattering is described. Concentrating on charm quark and D^*(2010) production at HERA, several distributions are presented and their variation with respect to charm quark mass, parton distribution set, and renormalization-factorization scale is studied.

B. W. Harris; J. Smith

1997-06-11T23:59:59.000Z

184

Polarization Analysis of Thermal-Neutron Scattering  

Science Journals Connector (OSTI)

A triple-axis neutron spectrometer with polarization-sensitive crystals on both the first and third axes is described. The calculation of polarized-neutron scattering cross sections is presented in a form particularly suited to apply to this instrument. Experimental results on nuclear incoherent scattering, paramagnetic scattering, Bragg scattering, and spin-wave scattering are presented to illustrate the possible applications of neutron-polarization analysis.

R. M. Moon; T. Riste; W. C. Koehler

1969-05-10T23:59:59.000Z

185

Electromagnetic wave scattering by Schwarzschild black holes  

E-Print Network [OSTI]

We analyze the scattering of a planar monochromatic electromagnetic wave incident upon a Schwarzschild black hole. We obtain accurate numerical results from the partial wave method for the electromagnetic scattering cross section, and show that they are in excellent agreement with analytical approximations. The scattering of electromagnetic waves is compared with the scattering of scalar, spinor and gravitational waves. We present a unified picture of the scattering of all massless fields for the first time.

Luís C. B. Crispino; Sam R. Dolan; Ednilton S. Oliveira

2009-05-20T23:59:59.000Z

186

Performance Assessment of Bi-Directional Knotless Tissue-Closure Devices in Juvenile Chinook Salmon Surgically Implanted with Acoustic Transmitters, 2009 - Final Report  

SciTech Connect (OSTI)

The purpose of this report is to assess the performance of bi-directional knotless tissue-closure devices for use in tagging juvenile salmon. This study is part of an ongoing effort at Pacific Northwest National Laboratory (PNNL) to reduce unwanted effects of tags and tagging procedures on the survival and behavior of juvenile salmonids, by assessing and refining suturing techniques, suture materials, and tag burdens. The objective of this study was to compare the performance of the knotless (barbed) suture, using three different suture patterns (treatments: 6-point, Wide “N”, Wide “N” Knot), to the current method of suturing (MonocrylTM monofilament, discontinuous sutures with a 2×2×2×2 knot) used in monitoring and research programs with a novel antiseptic barrier on the wound (“Second Skin”).

Woodley, Christa M.; Wagner, Katie A.; Bryson, Amanda J.

2012-11-09T23:59:59.000Z

187

Coherent neutron scattering response from glassy glycerol  

Science Journals Connector (OSTI)

We report on inelastic neutron scattering measurements of fully deuterated glassy glycerol at temperatures between 15 K to 180 K. Incident energies of 40 and 100 meV and momentum transfers up to ?12 A?-1 were used. Analysis of the static structure factor calculated as the zeroth-frequency moment of S(Q,?) enabled us to derive valuable structural information on the intra- and intermolecular correlations. Generalized frequency distributions are derived from the spectra and are used to calculate the relevant thermodynamic properties of the material using a quasiharmonic approximation. Estimates are also made for the first order anharmonic effects. Some wave-vector-dependent effects, such as the reduced frequency moments of S(Q,?) are also evaluated, and their physical meaning discussed in some detail. © 1996 The American Physical Society.

J. Dawidowski; F. J. Bermejo; R. Fayos; R. Fernández Perea; S. M. Bennington; A. Criado

1996-05-01T23:59:59.000Z

188

Mapping the Energy Distribution of SERRS Hot Spots from Anti-Stokes to Stokes Intensity Ratios  

E-Print Network [OSTI]

Mapping the Energy Distribution of SERRS Hot Spots from Anti- Stokes to Stokes Intensity Ratios in the anti-Stokes to Stokes intensity ratios in single-molecule surface-enhanced resonance Raman scattering-enhanced Raman scattering. Moreover, a methodology to estimate the distribution of resonance energies

Brolo, Alexandre G.

189

Observed Surface Reflectance Distributions in the Southern Great Plains During ALIVE  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Surface Reflectance Distributions Surface Reflectance Distributions in the Southern Great Plains During ALIVE Kirk Knobelspiesse 1 , Brian Cairns 1 , Andrew Lacis 2 , Mikhail Alexandrov 2 , Barbara Carlson 2 and Beat Schmid 3 1 Department of Applied Physics and Applied Mathematics, Columbia University 2 NASA Goddard Institute for Space Studies 3 Pacific Northwest National Laboratory * Surface albedo can be measured from the ground with broadband instruments. * Albedo can be measured from space if the atmospheric effect is removed and many view geometries are available. The measured Bidirectional Reflectance Distribution Function (BRDF) is angularly integrated to compute the albedo. * Studies of the former (Yang, 2006) and the latter (Liang et al. 2005; Wang et al. 2006) do not always agree.

190

NXS 2010 - Neutron Scattering School  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2-26, 2010 2-26, 2010 Argonne National Laboratory, Argonne, IL Oak Ridge National Laboratory, Oak Ridge, TN NXS2010 Travel Airport Shuttles Departure Flights Schedule Participants Lectures Lecturers Lecture Notes/Videos Experiments Schedule, Desc, Groups Student Presentations ANL Facilities APS Facility ANL Map ANL Visitor's Guide ORNL Facilities HFIR Facility SNS Facility HFIR/SNS Map Access Requirements ANL ORNL Rad Worker Training Study Guide Wireless Networks ANL ORNL Safety & Security Rules ANL ORNL NSSA New Initiatives NSSA Weblink Contacts ANL ORNL 12th National School on Neutron & X-ray Scattering 2009 Neutron Scattering School participants 2010 National School Participants Students share their thoughts about NXS 2010. Purpose: The main purpose of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major neutron and x-ray facilities. Lectures, presented by researchers from academia, industry, and national laboratories, will include basic tutorials on the principles of scattering theory and the characteristics of the sources, as well as seminars on the application of scattering methods to a variety of scientific subjects. Students will conduct four short experiments at Argonne's Advanced Photon Source and Oak Ridge's Spallation Neutron Source and High Flux Isotope Reactor facilities to provide hands-on experience for using neutron and synchrotron sources.

191

Neutron scattering investigations on methyl group dynamics in polymers.  

E-Print Network [OSTI]

Among the different dynamical processes that take place in polymers, methyl group rotation is perhaps the simplest one, since all the relevant interactions on the methyl group can be condensed in an effective mean-field one-dimensional potential. Recent experimental neutron scattering results have stimulated a new revival of the interest on methyl group dynamics in glasses and polymer systems. The existence of quantum rotational tunnelling of methyl groups in polymers was expected for a long time but only very recently (1998), these processes have been directly observed by high-resolution neutron scattering techniques. This paper revises and summarizes the work done on this topic over last ten years by means of neutron scattering. It is shown that the results obtained in many chemically and structurally different polymers can be consistently described in the whole temperature range — from the quantum tunnelling limit to the classical hopping regime — as well as in the librational spectrum, in terms of the Rotation Rate Distribution Model (RRDM), which was first proposed in 1994. This model introduces a distribution of potential barriers for methyl group rotation, which is associated to the disorder present in any structural glass. The molecular and structural origin of the barrier distribution in polymers is discussed on the basis of a huge collection of investigations reported in the literature, including recent fully atomistic molecular dynamics simulations.

Juan Colmenero; Angel J. Moreno; Angel Alegría

2005-01-01T23:59:59.000Z

192

Distribution Workshop  

Broader source: Energy.gov [DOE]

On September 24-26, 2012, the GTT presented a workshop on grid integration on the distribution system at the Sheraton Crystal City near Washington, DC.

193

Probing Ag nanoparticle surface oxidation in contact with (in)organics: an X-ray scattering and fluorescence yield approach  

Science Journals Connector (OSTI)

An advanced characterization approach to spatially resolve the reactions occurring at the interface between silver nanoparticles and a simple aqueous system is presented. Both phase and chemical distributions were obtained from X-ray scattering and fluorescence yield techniques.

Levard, C.

2011-10-06T23:59:59.000Z

194

NXS 2013 - Neutron Scattering School  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

5th National School on Neutron and X-Ray Scattering 5th National School on Neutron and X-Ray Scattering August 10-24, 2013 Argonne National Laboratory, Argonne, IL Oak Ridge National Laboratory, Oak Ridge, TN NXS2013 Schedule Participants Image Gallery Travel Info Thank you Lectures Lecture Notes/Videos Experiments ANL Facilities ANL Map (jpg) ANL Map (pdf) ANL Visitor's Guide ORNL Facilities HFIR Facility SNS Facility HFIR/SNS Map Wireless Networks ORNL Safety & Security Rules ORNL NSSA Weblink Contacts ANL ORNL 2013 NXS School Participants 2013 NXS Participants. NXS interveiws 2013 Click the image to download the video. Video Interviews: Participants answer questions about their experiences at NXS 2011. Your feedback about lectures and experiments is important for evaluating this year's Neutron and X-ray Scattering School and for making improvements for future participants. We sincerely hope that each of you will complete the survey by the end of the school.

195

Nuclear-resonant electron scattering  

Science Journals Connector (OSTI)

We investigate nuclear-resonant electron scattering as occurring in the two-step process of nuclear excitation by electron capture (NEEC) followed by internal conversion. The nuclear excitation and decay are treated by a phenomenological collective model in which nuclear states and transition probabilities are described by experimental parameters. We present capture rates and resonant strengths for a number of heavy-ion collision systems considering various scenarios for the resonant electron-scattering process. The results show that for certain cases resonant electron scattering can have significantly larger resonance strengths than NEEC followed by the radiative decay of the nucleus. We discuss the impact of our findings on the possible experimental observation of NEEC.

Adriana Pálffy and Zoltán Harman

2008-04-04T23:59:59.000Z

196

Scattering, Inverse Scattering and Resonances in R Plamen Stefanov  

E-Print Network [OSTI]

Apr 18, 2013 ... material comes from the books and the lecture notes of Melrose [9] ... A few remarks about the Stationary Scattering Theory vi .... density on the unit sphere. .... Remember, we need a kernel that is a tempered function of ? for ? ...

2013-04-18T23:59:59.000Z

197

SCATTERING MATRICES AND SCATTERING GEODESICS OF LOCALLY SYMMETRIC SPACES  

E-Print Network [OSTI]

variables d'#19;energie. D#19;e#12;nissons pour cela les g#19;eod#19;esiques de scattering de l'une telle g#19;eod#19;esique le temps qu'elle passe dans un domaine compact #12;x#19;e. Nous prouvons que

Zworski, Maciej

198

K+-nucleus elastic scattering at intermediate energies  

Science Journals Connector (OSTI)

Using the Coulomb modified Glauber model, we analyze the elastic angular distribution and reaction (?R) and total (?tot) cross sections of K+-12C at 635, 715, and 800 MeV/c, and of K+-40Ca at 800 MeV/c. The basic (input) K+N amplitude is taken from the phase shift analysis, and for nuclear form factors we use the nucleon density distributions as obtained from the analyses of intermediate energy proton scattering experiments and the relativistic mean field (RMF) calculations. The analysis also considers the nuclear medium effects, and predicts the in-medium behavior of the K+N amplitude. We find that the elastic angular distribution is sensitive to the choice of the nucleon density distributions, whereas the nuclear medium effects are better seen in the study of reaction and total cross sections.

Deeksha Chauhan and Z. A. Khan

2012-06-13T23:59:59.000Z

199

o r est la coordonne du neutron s celle du nuclon optique. La formule (1) conduit une distribution  

E-Print Network [OSTI]

. Szteinsznaider and myself. We have measured the angular distribution of the inelastic scattered neutrons on 56Fe neu- trons the number of neutrons scattered at 30° is the same as at 150° with 20 % approximation. To conclude, we have not detected any direct interaction in the inelastic scattering of neutrons at low energy

Boyer, Edmond

200

Incoherent Neutron Scattering by Polycrystals  

Science Journals Connector (OSTI)

General expressions are given for the first terms in the expansion in powers of the neutron to nuclear mass ratio of the total cross section for incoherent scattering of neutrons by polycrystals. Special limiting cases of these expressions had been published earlier.

G. Placzek

1957-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Scattering of Neutrons by Protons  

Science Journals Connector (OSTI)

... THEORETICAL investigations of the interaction of protons and neutrons have been given by Wigner, Heisenberg and Major ana. A very valuable check on ... ana. A very valuable check on their conclusions is provided by the study of the scattering cross-section of the hydrogen nucleus for ...

E. T. BOOTH; C. HURST

1936-12-12T23:59:59.000Z

202

Pauli Principle and Pion Scattering  

DOE R&D Accomplishments [OSTI]

It is pointed out that if the Pauli principle is taken into account in the discussion of pion scattering by complex nuclei (as it ought, of course, to be) some rather implausible consequences of some earlier treatments of this problem can be avoided. (auth)

Bethe, H. A.

1972-10-00T23:59:59.000Z

203

Call issued for Lujan Neutron Scattering Center proposals  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Call issued for Lujan Neutron Scattering Center proposals Call issued for Lujan Neutron Scattering Center proposals The Lujan Neutron Scattering Center invites proposals addressing...

204

Characterization of Light Scattering in Transparent Polycrystalline Laser Ceramics  

E-Print Network [OSTI]

promotes the identification of bulk scattering and defectsfailure. Previously, identification of bulk scatter in PLMaccurate identification and characterization of bulk scatter

Sharma, Saurabh

2013-01-01T23:59:59.000Z

205

Pion inelastic scattering from sup 20 Ne  

SciTech Connect (OSTI)

Angular distributions for {sup 20}Ne({pi}{sup {plus minus}}, {pi}{sup {plus minus}}{prime}) were measured on the Energetic Pion Channel and Spectrometer (EPICS) at the Clinton P. Anderson Meson Physics Facility (LAMPF). Data were taken with both {pi}{sup {plus}} and {pi}{sup {minus}} over an angular range of 12{degree} to 90{degree} for T{sub {pi}}=180 MeV and with {pi}{sup +} from 15{degree} to 90{degree} for T{sub {pi}}=120 MeV. The data were analyzed using both the distorted-wave impulse approximation (DWIA) and the coupled-channels impulse approximation (CCIA) with collective transition densities. In addition, microscopic transition densities were used in the DWIA analysis for states in the lowest rotational bands. The transitions to the 6.73-MeV 0{sup +} and several 1{sup {minus}} states, including the states at 5.79 MeV and 8.71 MeV, were studied using several models for the transition density. Strong evidence for the importance of two-step routes in pion inelastic scattering was seen in several angular distributions, including the 5.79-MeV 1{sup {minus}}, the first three 4{sup +} states, and the 8.78-MeV 6{sup +}. 100 refs., 81 figs., 33 tabs.

Burlein, M. (Pennsylvania Univ., Philadelphia, PA (USA). Dept. of Physics)

1989-12-01T23:59:59.000Z

206

Strong coupling effects in near-barrier heavy-ion elastic scattering  

E-Print Network [OSTI]

Accurate elastic scattering angular distribution data measured at bombarding energies just above the Coulomb barrier have shapes that can markedly differ from or be the same as the expected classical Fresnel scattering pattern depending on the structure of the projectile, the target or both. Examples are given such as 18O + 184W and 16O + 148,152Sm where the expected rise above Rutherford scattering due to Coulomb-nuclear interference is damped by coupling to the target excited states, and the extreme case of 11Li scattering, where coupling to the 9Li + n + n continuum leads to an elastic scattering shape that cannot be reproduced by any standard optical model parameter set. The recent availability of high quality 6He, 11Li and 11Be data provides further examples of the influence that coupling effects can have on elastic scattering. Conditions for strong projectile-target coupling effects are presented with special emphasis on the importance of the beam-target charge combination being large enough to bring about the strong coupling effects. Several measurements are proposed that can lead to further understanding of strong coupling effects by both inelastic excitation and nucleon transfer on near-barrier elastic scattering. A final note on the anomalous nature of 8B elastic scattering is presented as it possesses a more or less normal Fresnel scattering shape whereas one would a priori not expect this due to the very low breakup threshold of 8B. The special nature of 11Li is presented as it is predicted that no matter how far above the Coulomb barrier the elastic scattering is measured, its shape will not appear as Fresnel like whereas the elastic scattering of all other loosely bound nuclei studied to date should eventually do so as the incident energy is increased, making both 8B and 11Li truly "exotic".

N. Keeley; K. W. Kemper; K. Rusek

2014-09-25T23:59:59.000Z

207

Quasi-Differential Neutron Scattering Measurements of 238 A.M. Daskalakis, R.M. Bahran, E.J. Blain, B.J. McDermott, S. Piela, and Y. Danon  

E-Print Network [OSTI]

Quasi-Differential Neutron Scattering Measurements of 238 U A.M. Daskalakis, R.M. Bahran, E between evaluations through the energy-angle distribution of neutrons from scattering and fission of 238 U using the Rensselaer Polytechnic Institute (RPI) neutron scattering system. Differential neutron

Danon, Yaron

208

Neutron Scattering Methods of Investigating Clay Systems  

Science Journals Connector (OSTI)

Of the techniques surveyed in the present proceedings, neutron scattering is probably the least familiar to clay ... a rather simple account of the theory of neutron scattering, while the third section describes ...

D. Keith Ross; Peter L. Hall

1980-01-01T23:59:59.000Z

209

10th LANSCE School on Neutron Scattering  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

10th LANSCE School on Neutron Scattering LANSCE 10th LANSCE School on Neutron Scattering Home Abstract Lecturers Hands-On Experiments Free Day About the School Sponsors FAQ's...

210

11th LANSCE School on Neutron Scattering  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

11th LANSCE School on Neutron Scattering LANSCE 11th LANSCE School on Neutron Scattering Home Abstract Lecturers Hands-On Experiments Free Day About the School Sponsors FAQ's...

211

Neutron Scattering Experiment on Solid 3He  

Science Journals Connector (OSTI)

Magnetic neutron scattering probes the order parameter symmetry and magnitude ... as well as exchange parameters in a critical scattering experiment above the ordering temperature. Therefore we propose an experim...

Stephan Schöttl; Konrad Siemensmeyer; Vitaliy Boyko…

2002-01-01T23:59:59.000Z

212

Coherent scattering from a free gas  

E-Print Network [OSTI]

We investigate decoherence in atom interferometry due to scattering from a background gas and show that the supposition that residual coherence is due to near-forward scattering is incorrect. In fact, the coherent part is ...

Sanders, Scott N.

213

Wealth Distribution  

Science Journals Connector (OSTI)

Walter: What is a just wealth distribution? In my view, it is one that results from respect for proper initial homesteading, for resulting private property rights, and, finally, from any legitimate subsequent ...

Four Arrows; Walter Block

2011-01-01T23:59:59.000Z

214

Penetration and scattering of lower hybrid waves by density fluctuations  

SciTech Connect (OSTI)

Lower Hybrid [LH] ray propagation in toroidal plasma is controlled by a combination of the azimuthal spectrum launched from the antenna, the poloidal variation of the magnetic field, and the scattering of the waves by the density fluctuations. The width of the poloidal and radial RF wave spectrum increases rapidly as the rays penetrate into higher density and scatter from the turbulence. The electron temperature gradient [ETG] spectrum is particularly effective in scattering the LH waves due to its comparable wavelengths and parallel phase velocities. ETG turbulence is also driven by the radial gradient of the electron current density giving rise to an anomalous viscosity spreading the LH-driven plasma currents. The scattered LH spectrum is derived from a Fokker-Planck equation for the distribution of the ray trajectories with a diffusivity proportional to the fluctuations. The LH ray diffusivity is large giving transport in the poloidal and radial wavenumber spectrum in one - or a few passes - of the rays through the core plasma.

Horton, W. [Institute for Fusion Studies, University of Texas at Austin (United States); Goniche, M.; Peysson, Y.; Decker, J.; Ekedahl, A.; Litaudon, X. [CEA, IRFM, F-13108 St-Paul-Lez-Durance (France)

2014-02-12T23:59:59.000Z

215

High-Energy Electron Scattering and Nuclear Structure Determinations  

Science Journals Connector (OSTI)

Electrons of energies 125 and 150 Mev are deflected from the Stanford linear accelerator and brought to a focused spot of dimension 3 mm×15 mm at a distance of 9 feet from a double magnet deflecting system. The focus is placed at the center of a brass-scattering chamber of diameter 20 inches. Thin foils are inserted in the chamber and elastically-scattered electrons from these foils pass through thin aluminum windows into the vacuum chamber of a double focusing analyzing magnet of the inhomogeneous field type. The energy resolution of the magnet has been about 1.5 percent in these experiments. This resolution is enough to separate clearly hydrogen or deuterium elastic peaks from carbon peaks in the same scattering target. The energy loss in the foils is readily measurable. In the case of light nuclei, e.g., H, D, Be, C, the shift of the peak of the elastic curve as a function of scattering angle indicates the recoil of the struck nucleus. Relative angular distributions are measured for Be, Ta, Au, and Pb. It is possible to interpret these data in terms of a variable charge density within the nucleus.

R. Hofstadter; H. R. Fechter; J. A. McIntyre

1953-11-15T23:59:59.000Z

216

Special Distribution  

Office of Legacy Management (LM)

Special Distribution Special Distribution Issued: December 1977 ',, Radiological Survey and Decontamination of the Former Main Technical Area (TA-1) at Los Alamos, New Mexico Compiled by A. John Ahlquist Alan K. Stoker Linda K. Trocki c laboratory of, the University of California LOS ALAMOS, NEW MEXICO 87545 An Alfirmdve Action/Equal Opportunity Employer ..-_- .-- .--.-. c T -,--... _ _._-r..l __,.. - .-,_.. ..- _._ -- .--. " . . _ . - . c- - . . . _ -. . _ . - . - . _ - - n - _ _~ ~_. __ _ ~~_ --..&e+ L.';; CONTENTS ABSTRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .._____ 1 EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .._... _._ 2 I. BACKGROUND .............................................. 15

217

Purdue University :: College of Science :: Scattering, Imaging ...  

E-Print Network [OSTI]

... inverse scattering in media of low regularity, highly discontinuous and random media - structured matrix based methods, and massively parallel algorithms

218

Scattering Anisotropies in n-Type Silicon  

Science Journals Connector (OSTI)

Measurements have been made of magnetoresistance effects in several relatively pure samples of n-type silicon for the purpose of obtaining information on scattering anisotropies. The results indicate that the ratios of relaxation times parallel and perpendicular to a constant-energy-spheroid axis in the six-valley conduction band of silicon are ?II???23 for acoustic-mode intravalley lattice scattering and ?II??>1 for ionized-impurity scattering. Intervalley lattice scattering, important at higher temperatures, is isotropic.

Donald Long and John Myers

1960-10-01T23:59:59.000Z

219

Neutron scattering reaps Nobel for physics  

Science Journals Connector (OSTI)

... through its joint award to Bertrand Brockhouse and Clifford Shull for their work in developing neutron inelastic ... inelastic scattering and ...

Philip Ball

1994-10-20T23:59:59.000Z

220

Neutron-Proton Interaction: The Scattering of Neutrons by Protons  

Science Journals Connector (OSTI)

The inadequacy of present theories of proton-neutron interaction is shown in work in which 730 proton tracks produced by collisions of fast neutrons with hydrogen nuclei have been studied and measured to determine the distribution-in-angle. The recoils have been observed in three gaseous media; hydrogen, ethylene and hydrogen sulphide, by the use of a sylphon-type Wilson chamber and two cameras mounted in such a way as to give two views of each recoil, thus enabling a stereoscopic projection and a direct measurement of the angle of scattering to be made for each track. In this way it is found that the intensity distribution of recoil protons shows a maximum in the neighborhood of 25°. The distribution referred to unit solid angle in each angle interval exhibits a sharp maximum at 0° in close agreement with the work of Kurie, but in contradiction to those who have believed the scattering to be of the classical type. Various factors, both geometrical and statistical, which may lead to distortion of the angular distribution are cited, and it is shown that their effect is taken into account in these experiments, but not necessarily in those of the other workers. The contradictions in the results reported at present in the literature are assumed to arise from these factors. The bearing of the distribution found in these experiments on the neutron-proton inter-action is considered in the light of the modern nuclear theories and evidence is deduced for an exchange or some other type of interaction at energies lower than predicted on the basis of these theories. The mechanism favored by both the classical and quantum theories, namely elastic collision of like spheres, is inadequate to explain the distribution. The present distribution is found to be consistent with Fermi's explanation for the efficiency of hydrogen nuclei in slowing fast neutrons, but indicates an even higher efficiency.

William D. Harkins; Martin D. Kamen; Henry W. Newson; David M. Gans

1936-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Requirements, possible alternatives & international NEUTRON SCATTERING  

E-Print Network [OSTI]

Requirements, possible alternatives & international NEUTRON SCATTERING DETECTORS for Rob Dimeo NIST neutron scattering instruments are the most demanding require background low #12;#12;The Helium-3 Supply Crisis ­ Alternative Techniques to Helium-3 based Detectors for Neutron Scattering Applications

Dimeo, Robert M.

222

Measurements of the Thermal Neutron Scattering Kernel  

E-Print Network [OSTI]

Measurements of the Thermal Neutron Scattering Kernel Li (Emily) Liu, Yaron Danon, Bjorn Becker and discussions Problems and Future study Questions #12;3 M. Mattes and J. Keinert, Thermal Neutron Scattering experimental data used was from 1973-1974! M. Mattes and J. Keinert, Thermal Neutron Scattering Data

Danon, Yaron

223

Neutron Scattering Studies of Correlated Electron Systems  

E-Print Network [OSTI]

Neutron Scattering Studies of Correlated Electron Systems Lucy Helme Thesis submitted submitted for the Degree of Doctor of Philosophy, Trinity Term 2006 This thesis presents neutron scatteringO2, through inelastic neutron scattering studies of the crystal field transitions above and below

Boothroyd, Andrew

224

Studies in Small Angle Scattering Techniques  

E-Print Network [OSTI]

. Knud Møllenbach Abstract. Small angle scattering of neutrons, x-rays and y-rays are found among scattering as well as small angle y-ray diffraction. The study of neutron scat- tering from formations limit of the neutron diffractometer 20 3. SMALL ANGLE SCATTERING INSTRUMENTS 22 3.1. The double crystal

225

Feature Article NEXAFS microscopy and resonant scattering  

E-Print Network [OSTI]

and conven- tional electron, X-ray and neutron scattering. We provide an overview of these synchrotron based and derivative struc- tures, ranging from spectroscopy to mechanical analysis and neutron scattering [9,10]. SomeFeature Article NEXAFS microscopy and resonant scattering: Composition and orientation probed

Hitchcock, Adam P.

226

| Los Alamos National Laboratory | Total Scattering Developments forTotal Scattering Developments for  

E-Print Network [OSTI]

Laboratory | Total Scattering at the Lujan Center Neutron Powder Diffractometer (NPDF) High-Intensity Powder. Shoemaker, et al., Reverse Monte Carlo neutron scattering study of disordered crystalline materials neutron| Los Alamos National Laboratory | Total Scattering Developments forTotal Scattering Developments

Magee, Joseph W.

227

Absorption and scattering images of heterogeneous scattering media can be simultaneously reconstructed  

E-Print Network [OSTI]

Absorption and scattering images of heterogeneous scattering media can be simultaneously designed phantom experimental study aimed to provide solid evidence that both absorption and scattering the important absorption­scattering cross-talk issue. In this regard, we develop a simple normalizing scheme

Khan, Taufiquar R.

228

LANSCE | Lujan Neutron Scattering Center  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Department of Energy, National Office of Science Department of Energy, National Office of Science science.energy.gov Department of Energy, National Nuclear Security Administration nnsa.energy.gov Lujan Neutron Scattering Center Logo Lujan Center Mission The Lujan Center delivers science by exploiting the unique characteristics of intense beams of pulsed neutrons for academia, national security, and industry. Lujan Center Vision The Lujan Center will operate a world class user program in the service of the nation. Lujan Center scientists will be recognized for their leadership and innovation in neutron scattering. Lujan Center at LANSCE The Lujan Center is one of five user facilities supported by the LANSCE accelerator which is stewarded. Funding to operate 10 instruments in a national user program is provided by the Department of Energy's Office of

229

Spin Waves and Neutron Scattering  

Science Journals Connector (OSTI)

A review is given of the problems in this field and of the possibilities opened up by the fact that neutron scattering gives access to the time?dependent spin?correlation function in magnets over virtually the whole range of q t and T. New experimental results are given in connection with magnon energy linewidth and renormalization and some data are presented for the spin?wave stiffness of bcc 3d transition?metal alloys as a function of electron concentration showing effects explained by the electronic density?of?states curve. It is pointed out that the ground?state fluctuations of magnets give rise to effects in the formulas for neutron scattering.

R. D. Lowde

1965-01-01T23:59:59.000Z

230

Slow Neutron Scattering by the Titanium Isotopes  

Science Journals Connector (OSTI)

Neutron diffraction studies are reported on isotopically enriched samples of TiO2 from which are evaluated the coherent scattering amplitudes of the titanium isotopes. Scattering amplitudes of +0.48, +0.33, -0.58, +0.08, and +0.55×10-12 cm were established for the titanium isotopes of mass 46, 47, 48, 49, and 50, respectively. The major isotope Ti48 is thus responsible for the anomalous scattering amplitude, -0.34×10-12 cm, characteristic of the normal element. Pronounced nuclear scattering resonance effects on the observed neutron scattering are suggested to occur for most of the isotopes.

C. G. Shull; M. K. Wilkinson; M. H. Mueller

1960-05-01T23:59:59.000Z

231

Calculations for methane scattering from LiF(001)  

Science Journals Connector (OSTI)

Calculations are presented for the scattering of CH4 molecules from a LiF(001) surface. The theory utilized is a mixed classical-quantum model that includes energy and momentum transfers between the surface and projectile for translational and rotational motions as well as internal mode excitation of the projectile molecule. The translation and rotation motions, including multiphonon excitations with the surface, are treated with classical dynamics. Internal vibrational mode excitation of the molecules is treated quantum mechanically with extension to arbitrary numbers of modes and arbitrary excitation quantum numbers. The results of calculations are compared with recent high-precision measurements of the scattering of CH4 molecules from clean, ordered LiF(001). The calculated results for energy-resolved spectra and for the angular distributions are in good agreement with experiment.

Iryna Moroz and J. R. Manson

2004-05-19T23:59:59.000Z

232

Parity-Violating Electron Scattering: New Results and Future Prospects  

SciTech Connect (OSTI)

We discuss the status and prospects of an experimental program of parity-violating asymmetry measurements in the scattering of longitudinally polarized electrons off unpolarized fixed targets. One thrust is the measurements of nucleon neutral weak form factors at intermediate four-momentum transfer (0.1 < Q2 < 1) (GeV/c)2 which provide information about the role of virtual strange quarks on the charge and current distributions inside nucleons. A new topic is the elastic neutral weak amplitude from scattering off a heavy spinless nucleus, which is sensitive to the presence of a neutron skin. Finally, we discuss the neutral current elastic amplitude at very low Q2, which allows precision measurements of the weak mixing angle at low energy and is thus sensitive to new physics at the TeV scale. The physics implications of recent results, potential measurements from experiments under construction as well as new ideas at future facilities are discussed.

Krishna S. Kumar

2006-11-01T23:59:59.000Z

233

Study of neutron scattering contribution on Hp(10) and H*(10) calibration in the Brazilian National Low Scattering Laboratory  

Science Journals Connector (OSTI)

......Dosimetry (Neudos 12) Study of neutron scattering contribution on H p(10...22783-127 RJ, Brazil The neutron scattering at the Low Scattering Laboratory...of this work is to study the neutron scattering contribution for the quantities......

B. M. Freitas; W. W. Pereira; K. C. S. Patrão; E. S. Fonseca; C. L. P. Mauricio

2014-10-01T23:59:59.000Z

234

Neutron Scattering at 2.2 Mev by Time of Flight  

Science Journals Connector (OSTI)

A millimicrosecond time-of-flight technique has been applied to a study of the scattering of 2.2-Mev neutrons from targets of Fe, Pb206, and Y. The 3-Mev phase-focused proton beam from the BNL 18-inch cyclotron was used to produce high-intensity neutron pulses in the T(p, n)He3 reaction. The angular distributions of the elastically scattered neutrons have been measured for the above targets. The angular distributions of the inelastically scattered neutrons from the 0.845-Mev level in Fe56 and from the 0.803-Mev level in Pb206 have been carefully studied, and were found to be symmetric about ?c.m.=90°. The angular distributions of the inelastically scattered neutrons from levels at 1.34 and 1.43 Mev in Pb206 and from levels at 0.913 and 1.53 Mev in Y have been measured, and also appear to be symmetric about ?c.m.=90°. The inelastic scattering from Pb206 shows evidence for a new level at 1.15 Mev.

H. H. Landon; A. J. Elwyn; G. N. Glasoe; S. Oleksa

1958-11-15T23:59:59.000Z

235

Fast Scatter Artifacts Correction for Cone-Beam CT without System Modification and Repeat Scan  

E-Print Network [OSTI]

We provide a fast and accurate scatter artifacts correction algorithm for cone beam CT (CBCT) imaging. The method starts with an estimation of coarse scatter profile for a set of CBCT images. A total-variation denoising algorithm designed specifically for Poisson signal is then applied to derive the final scatter distribution. Qualitatively and quantitatively evaluations using Monte Carlo (MC) simulations, experimental CBCT phantom data, and \\emph{in vivo} human data acquired for a clinical image guided radiation therapy were performed. Results show that the proposed algorithm can significantly reduce scatter artifacts and recover the correct HU within either projection domain or image domain. Further test shows the method is robust with respect to segmentation procedure.

Zhao, Wei; Wang, Luyao

2015-01-01T23:59:59.000Z

236

DISTRIBUTION CATEGORY  

Office of Scientific and Technical Information (OSTI)

DISTRIBUTION CATEGORY DISTRIBUTION CATEGORY uc-11 I A W E N C E LIVERMORE IABORATORY University of Cahfmia/Livermore, California/94550 UCRL-52658 CALCULATION OF CHEMICAL EQUILIBRIUM BETWEEN AQUEOUS SOLUTION AND MINERALS: THE EQ3/6 - - SOFTWARE PACKAGE T. J. Wolery MS. date: February 1, 1979 . . - . . - . Tho rcpon rn prepared as an account of work sponsored by the United Stater Government. Seither Lhc Urutcd Stater nor the Umted Stater Department of Energy, nor any of their employees. nor any of their E O ~ ~ ~ B C I O I S . rubcontracton. o r their employees. makes any warranr)., exprcs or !mplwd. or assumes any legal liability or respanability io: the ~ c c u o c y . complctencn or uvfulneu of any miormarlon. apparatcr. product or p r o m s dtwlorcd. or r c p r e v n u that its UP would not infringe privately owned r

237

Multiphonon Raman scattering in graphene  

Science Journals Connector (OSTI)

We report on multiphonon Raman scattering in graphene samples. Higher-order combination modes involving three and four phonons are observed in single-layer, bilayer, and few-layer graphene samples prepared by mechanical exfoliation. The intensity of the higher-order phonon modes (relative to the G peak) is highest in single-layer graphene and decreases with increasing layers. In addition, all higher-order modes are observed to upshift in frequency almost linearly with increasing graphene layers, betraying the underlying interlayer van der Waals interactions.

Rahul Rao; Derek Tishler; Jyoti Katoch; Masa Ishigami

2011-09-12T23:59:59.000Z

238

Completeness for sparse potential scattering  

SciTech Connect (OSTI)

The present paper is devoted to the scattering theory of a class of continuum Schrödinger operators with deterministic sparse potentials. We first establish the limiting absorption principle for both modified free resolvents and modified perturbed resolvents. This actually is a weak form of the classical limiting absorption principle. We then prove the existence and completeness of local wave operators, which, in particular, imply the existence of wave operators. Under additional assumptions on the sparse potential, we prove the completeness of wave operators. In the context of continuum Schrödinger operators with sparse potentials, this paper gives the first proof of the completeness of wave operators.

Shen, Zhongwei, E-mail: zzs0004@auburn.edu [Department of Mathematics and Statistics, Auburn University, Auburn, Alabama 36849 (United States)] [Department of Mathematics and Statistics, Auburn University, Auburn, Alabama 36849 (United States)

2014-01-15T23:59:59.000Z

239

Neutron-Neutron Quasifree Scattering  

Science Journals Connector (OSTI)

The reaction D(n ,2n)p has been measured at Einc=14.1 MeV, ?n (3)=?n(4)=30?, ?=180?, and the results are compared with the predictions of two separable-potential models. Neutron-proton and proton-proton quasifree scattering from nucleon + deuteron reactions at 14 MeV are also compared with the predictions of the same models. The upper limit of 2 mb/sr2 is determined for the reaction D(n,n?)d.

Ivo Slaus; J. W. Sunier; G. Thompson; J. C. Young; J. W. Verba; D. J. Margaziotis; P. Doherty; R. T. Cahill

1971-03-29T23:59:59.000Z

240

LED lamp or bulb with remote phosphor and diffuser configuration with enhanced scattering properties  

DOE Patents [OSTI]

An LED lamp or bulb is disclosed that comprises a light source, a heat sink structure and an optical cavity. The optical cavity comprises a phosphor carrier having a conversions material and arranged over an opening to the cavity. The phosphor carrier comprises a thermally conductive transparent material and is thermally coupled to the heat sink structure. An LED based light source is mounted in the optical cavity remote to the phosphor carrier with light from the light source passing through the phosphor carrier. A diffuser dome is included that is mounted over the optical cavity, with light from the optical cavity passing through the diffuser dome. The properties of the diffuser, such as geometry, scattering properties of the scattering layer, surface roughness or smoothness, and spatial distribution of the scattering layer properties may be used to control various lamp properties such as color uniformity and light intensity distribution as a function of viewing angle.

Tong, Tao; Le Toquin, Ronan; Keller, Bernd; Tarsa, Eric; Youmans, Mark; Lowes, Theodore; Medendorp, Jr., Nicholas W; Van De Ven, Antony; Negley, Gerald

2014-11-11T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Parton distributions for the LHC  

E-Print Network [OSTI]

We present updated leading-order, next-to-leading order and next-to-next-to-leading order parton distribution functions ("MSTW 2008") determined from global analysis of hard-scattering data within the standard framework of leading-twist fixed-order collinear factorisation in the MSbar scheme. These parton distributions supersede the previously available "MRST" sets and should be used for the first LHC data-taking and for the associated theoretical calculations. New data sets fitted include CCFR/NuTeV dimuon cross sections, which constrain the strange quark and antiquark distributions, and Tevatron Run II data on inclusive jet production, the lepton charge asymmetry from W decays and the Z rapidity distribution. Uncertainties are propagated from the experimental errors on the fitted data points using a new dynamic procedure for each eigenvector of the covariance matrix. We discuss the major changes compared to previous MRST fits, briefly compare to parton distributions obtained by other fitting groups, and giv...

Martin, A D; Thorne, R S; Watt, G

2009-01-01T23:59:59.000Z

242

Neutrino Scattering on Glass: NuSOnG  

Science Journals Connector (OSTI)

These proceedings describe the physics goals and initial design for a new experiment: NuSOnG—Neutrino Scattering On Glass. The design will yield about two orders of magnitude higher statistics than previous high energy neutrino experiments observed in a detector optimized for low hadronic energy and electromagnetic events. As a result the purely weak processes ? ? +e ? ?? ? +e ? and ? ? +e ? ?? e +? ? (inverse muon decay) can be measured with high accuracy for the first time. This allows important precision electroweak tests and well as direct searches for new physics. The high statistics also will yield the world's largest sample of Deep Inelastic (DIS) events for precision parton distribution studies.

J. M. Conrad; NuSOnG EOI

2008-01-01T23:59:59.000Z

243

A QCD analysis of diffractive deep-inelastic scattering data  

E-Print Network [OSTI]

We perform a novel type of analysis of diffractive deep-inelastic scattering data, in which the input parton distributions of the Pomeron are parameterised using the perturbative QCD expressions. In particular, we treat individually the components of the Pomeron of different size. We are able to describe simultaneously both the recent ZEUS and H1 diffractive data. In addition to the usual two-gluon model for the perturbative Pomeron, we allow for the possibility that it may be made from two sea quarks.

Martin, A D; Watt, G

2004-01-01T23:59:59.000Z

244

Chaotic Scattering and Self-Organization in Spheromak Sustainment  

Science Journals Connector (OSTI)

Flux core spheromak sustainment by electrostatic helicity injection is studied in resistive MHD. The geometry has magnetized electrodes at the ends held at a potential difference V. For V>Vc the central current column is kink unstable. The nonlinear state with V just above Vc has a large volume of flux surfaces, with rotational transform provided by the helical kinking of the column. As V increases the kink becomes stronger, the tori are destroyed, and the field lines exhibit chaotic scattering. The distribution of field line lengths L, related to confinement and parallel current density, is studied. At larger V or larger Lundquist number S, a limit cycle appears.

John M. Finn; Carl R. Sovinec; Diego del-Castillo-Negrete

2000-11-20T23:59:59.000Z

245

Scattering of coherent pulses on a two-level system  

E-Print Network [OSTI]

In this work, we consider a two-level system (TLS) coupled to a one-dimensional continuum of bosonic modes in a transmission line. Using the master equation approach, a method for determining the photon number distribution of the scattered field is outlined. Specifically, results for the reflected field when driving the TLS with a coherent pulse are given. While the one-photon probability is enhanced compared to the incident coherent field, the system is still not a good deterministic single-photon source. Extending the system to contain two separate transmission lines, however, output fields with one-photon probabilities close to unity can be reached.

Joel Lindkvist; Göran Johansson

2014-01-15T23:59:59.000Z

246

Small Angle X-Ray Scattering Detector  

DOE Patents [OSTI]

A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., qmax/qmin approx=lO0.

Hessler, Jan P.

2004-06-15T23:59:59.000Z

247

Inelastic light scattering and light emission from single and double wall carbon , Stephen Cronin2  

E-Print Network [OSTI]

surfactant suspensions. Keywords: carbon nanotubes, optical transition energies, chirality, photoluminescence of excitation energy from a distribution of single wall carbon nanotubes, in a surfactant suspensionInelastic light scattering and light emission from single and double wall carbon nanotubes Yan Yin1

248

Nuclear Effects in Deep Inelastic Scattering of Charged-Current Neutrino off Nuclear  

E-Print Network [OSTI]

Nuclear effect in the neutrino-nucleus charged-Current inelastic scattering process is studied by analyzing the CCFR and NuTeV data. Structure functions $F_2(x,Q^2)$ and $xF_3(x,Q^2)$ as well as differential cross sections are calculated by using CTEQ parton distribution functions and EKRS and HKN nuclear parton distribution functions, and compared with the CCFR and NuTeV data. It is found that the corrections of nuclear effect to the differential cross section for the charged-current anti-neutrino scattering on nucleus are negligible, the EMC effect exists in the neutrino structure function $F_2(x,Q^2)$ in the large $x$ region, the shadowing and anti-shadowing effect occurs in the distribution functions of valence quarks in the small and medium $x$ region,respectively. It is also found that shadowing effects on $F_2(x,Q^2)$ in the small $x$ region in the neutrino-nucleus and the charged-lepton-nucleus deep inelastic scattering processes are different. It is clear that the neutrino-nucleus deep inelastic scattering data should further be employed in restricting nuclear parton distributions.

Duan ChunGui; Li GuangLie; Shen PengNian

2006-04-18T23:59:59.000Z

249

Physical Reproduction of Materials with Specified Subsurface Scattering Milos Hasan1  

E-Print Network [OSTI]

to fabricate full 3D shapes. Abstract We investigate a complete pipeline for measuring, modeling, the pipeline of de- vice characterization, simulation, and goal-driven fabrication has remained underdeveloped. The distribution of this scattering is crucial to believable appearance of materials such as human skin, wax

250

Elastic Scattering of O16 on O18 Including Backward Angles  

Science Journals Connector (OSTI)

The elastic scattering of O16 on O18 has been measured for incident beam energies of Elab=24,28, and 32 MeV at center-of-mass angles up to 150°. The angular distributions exhibit pronounced oscillations at backward angles which may be interpreted as due to the occurrence of an elastic transfer.

C. K. Gelbke; R. Bock; P. Braun-Munzinger; D. Fick; K. D. Hildenbrand; A. Richter; W. Weiss

1972-12-18T23:59:59.000Z

251

Fusion Engineering and Design 53 (2001) 105111 Fast ion collective Thomson scattering, JET results  

E-Print Network [OSTI]

dynamics and specific issues for ion cyclotron resonance heating. © 2001 Elsevier Science B.V. All rights of energetic ion distributions generated by fusion reactions and ion cyclotron resonance heating (ICRH). CTS reserved. Keywords: Fast ions; Collective Thomson scattering; JET; TEXTOR; ICRH (Ion Cyclotron Resonance

Egedal, Jan

252

Bubble entrainment by breaking waves and their influence on optical scattering in the upper ocean  

E-Print Network [OSTI]

Bubble entrainment by breaking waves and their influence on optical scattering in the upper ocean's surface inject bubbles and turbulence into the water column. During periods of rough weather the scales and the turbulent transport of bubbles to depth. Depending on their concentrations and size distribution

Stramski, Dariusz

253

Thomson scattering measurements in atmospheric plasma jets  

Science Journals Connector (OSTI)

Electron temperature and electron density in a dc plasma jet at atmospheric pressure have been obtained using Thomson laser scattering. Measurements performed at various scattering angles have revealed effects that are not accounted for by the standard scattering theory. Differences between the predicted and experimental results suggest that higher order corrections to the theory may be required, and that corrections to the form of the spectral density function may play an important role.

G. Gregori; J. Schein; P. Schwendinger; U. Kortshagen; J. Heberlein; E. Pfender

1999-02-01T23:59:59.000Z

254

Polarization of Nucleons Elastically Scattered by Nuclei  

Science Journals Connector (OSTI)

The polarization of 424-Mev nucleons elastically scattered by nuclei is calculated by a method which is similar to the Born approximation, but in which the phase shifts of the incident plane wave due to the scattering potential is taken into consideration. A qualitative agreement with the experimental result is obtained if one uses the well parameters determined by Riesenfeld and Watson. Poor agreement at the diffraction minimum may be attributed to the existence of inelastic scattering in the experimental data.

Keiichi Nishimura

1958-06-01T23:59:59.000Z

255

Pion scattering and nuclear dynamics  

SciTech Connect (OSTI)

A phenomenological optical-model analysis of pion elastic scattering and single- and double-charge-exchange scattering to isobaric-analog states is reviewed. Interpretation of the optical-model parameters is briefly discussed, and several applications and extensions are considered. The applications include the study of various nuclear properties, including neutron deformation and surface-fluctuation contributions to the density. One promising extension for the near future would be to develop a microscopic approach based on powerful momentum-space methods brought to existence over the last decade. In this, the lowest-order optical potential as well as specific higher-order pieces would be worked out in terms of microscopic pion-nucleon and delta-nucleon interactions that can be determined within modern meson-theoretical frameworks. A second extension, of a more phenomenological nature, would use coupled-channel methods and shell-model wave functions to study dynamical nuclear correlations in pion double charge exchange. 35 refs., 11 figs., 1 tab.

Johnson, M.B.

1988-01-01T23:59:59.000Z

256

INVERSE SCATTERING PROBLEMS WITH MULTI-FREQUENCIES ...  

E-Print Network [OSTI]

variational problem is studied for the direct scattering; an energy estimate is given ..... It follows from Green's formula and the adjoint problem (2.23) that we have.

2015-01-25T23:59:59.000Z

257

Fast methods for inverse wave scattering problems  

E-Print Network [OSTI]

Inverse wave scattering problems arise in many applications including computerized/diffraction tomography, seismology, diffraction/holographic grating design, object identification from radar singals, and semiconductor ...

Lee, Jung Hoon, Ph. D. Massachusetts Institute of Technology

2008-01-01T23:59:59.000Z

258

Appendix - Neutron Scattering Lengths and Cross Sections  

Science Journals Connector (OSTI)

Abstract In this appendix, we present an updated table of neutron scattering lengths and cross sections for most of the known nuclides, based on preexisting works. We include the coherent and incoherent scattering lengths, as well as the spin-dependent scattering lengths b+ and b?, in cases where this information is available. Also presented are the scattering coherent, incoherent, total, and absorption cross sections. We present an overview of the fundamental theory of the magnitudes to which the table is referred, and also a summary of the main experimental techniques used in determining these magnitudes.

Javier Dawidowski; José Rolando Granada; Javier Roberto Santisteban; Florencia Cantargi; Luis Alberto Rodríguez Palomino

2013-01-01T23:59:59.000Z

259

26 Tesla DC Magnet for Neutron Scattering  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Previously, DC Magnets located at Neutron-Scattering Beamlines were commercially-manufactured superconducting magnets and limited to 17 T. A few pulsed magnet systems have been...

260

Scattering of Fast Neutrons by Boron  

Science Journals Connector (OSTI)

The cross section of boron for the scattering of fast neutrons through angles greater than 30° was measured at neutron energies between 0.2 and 3 Mev.

H. H. Barschall; M. E. Battat; W. C. Bright

1946-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Neutron-deuteron breakup and quasielastic scattering .  

E-Print Network [OSTI]

??Quasielastic scattering and deuteron breakup in the 200 MeV region is studied by impinging a pulsed neutron beam on a deuterium target at the Weapons… (more)

Ohlson, Alice Elisabeth

2009-01-01T23:59:59.000Z

262

Granular Structure Determined by Terahertz Scattering  

E-Print Network [OSTI]

Light-scattering in the terahertz region is demonstrated for granular matter. A quantum-cascade laser is used in a benchtop setup to determine the angle-dependent scattering of spherical grains as well as coffee powder and sugar grains. For the interpretation of the form factors for the scattering from single particles one has to go beyond the usual Rayleigh-Gans-Debye theory and apply calculations within Mie theory. In addition to single scattering also collective correlations can be identified and extracted as a static structure factor.

Philip Born; Nick Rothbart; Matthias Sperl; Heinz-Wilhelm Hübers

2013-12-23T23:59:59.000Z

263

Paramagnetic neutron scattering from Ni (invited)  

Science Journals Connector (OSTI)

New polarized beammeasurements have been carried out in the paramagnetic phase of 6 0Ni in order to enlarge the (q ?) range previously studied by Steinsvoll e t a l. Magnetic scattering has been detected up to halfway to the zone boundary. The results can be successfully interpreted in terms of a diffusive?type scattering function over an unexpected wide (q ?) range qneutron data are also compared with the predictions of the very recent band model by Callaway. Finally we point out important similarities and differences in the paramagnetic scattering from localized systems such as EuO and itinerant systems and discuss the universality of the paramagnetic scattering function.

P. Böni; G. Shirane

1985-01-01T23:59:59.000Z

264

Development of KSTAR Thomson scattering system  

SciTech Connect (OSTI)

To measure the electron temperature (T{sub e}) and electron density (n{sub e}) profiles in the Korean Superconducting Tokamak Advanced Research (KSTAR) device for the KSTAR third campaign (September 2010), we designed and installed a Thomson scattering system. The KSTAR Thomson scattering system is designed as a tangential Thomson scattering system and utilizes the N-, L-, and B-ports. The N-port is designed for the collection optics with a cassette system, the L-port is the laser input port, and the B-port is the location of the beam dump. In this paper, we will describe the final design of the KSTAR Thomson scattering system.

Lee, J. H.; Oh, S. T.; Wi, H. M. [National Fusion Research Institute, Gwahangno 113, Daejeon 305-333 (Korea, Republic of)

2010-10-15T23:59:59.000Z

265

Broadband and statistical characterization of echoes from random scatterers : application to acoustic scattering by marine organisms  

E-Print Network [OSTI]

The interpretation of echoes collected by active remote-sensing systems, such as sonar and radar, is often ambiguous due to the complexities in the scattering processes involving the scatterers, the environment, and the ...

Lee, Wu-Jung

2013-01-01T23:59:59.000Z

266

Method of analysis of multiphonon and multiple-scattering effects in inelastic neutron scattering experiments  

Science Journals Connector (OSTI)

We present experimental results of inelastic neutron scattering experiments on a Ti–Zr alloy, together ... measurements. A method of analysis of inelastic neutron scattering experiments is proposed, aimed at obta...

J. Dawidowski; G.J. Cuello; M. Koza; J.J. Blostein; G. Aurelio…

2002-12-01T23:59:59.000Z

267

Acoustic scattering by bubbles in naturally occurring mud sediments  

Science Journals Connector (OSTI)

Naturally occurring sediment mud contains bubbles created by decaying vegetable matter. Work reported by Preston Wilson etal. (ca. 2007) has determined via x-ray tomography systems that mud bubbles are not spherical in shape but resemble oblate spheroids and are “inhomogeneously distributed.” These features are explained in terms of the card-house structure of mud with an adaptation of the fracture mechanics ideas of Boudreau etal. (ca. 2002). The scattering of sound at low frequencies by such nonspherical bubbles has both monopole and dipole components. The scatteredwave associated with the monopole term is proportional to the bubble volume. The dipole term involves an effective entrained mass tensor which is found by a solution of Laplace's equation. All bubbles regardless of shape have a smallest resonance frequency and the scattered radiation near the resonance frequency is monopole in character. Example solutions for the resonance frequencies and the scattering near resonance are given for oblate spheroidal bubbles and a suggested interpolation from low frequencies to resonance frequencies is given. A discussion is also given of how one can make use of the range-evolving form of compact-source generated pulses to infer information about the bubbles near the propagation path.

Allan D. Pierce; Willam M. Carey

2011-01-01T23:59:59.000Z

268

Analysis of diffractive features in elastic scattering of {sup 7}Li by different target nuclei at different energies  

SciTech Connect (OSTI)

The diffractive features of angular distribution have been investigated by analyzing the experimental data for a set of elastic scattering processes of {sup 7}Li by different target nuclei at different laboratory energies. Both Frahn-Venter and McIntyre models are used to analyze experimental data of angular distribution for elastic scattering processes. The theoretical models can reasonably reproduce the general pattern of the data. Some geometrical parameters for colliding nuclei have been obtained from the elastic scattering processes. It is found that interpretation of the diffractive features of the data is model-independent. The values of extracted parameters, from adopted models, are found comparable to each other and to those of others. The total reaction cross section is correlated to the incident laboratory energy for each scattering and values of total reaction cross section are found comparable with those of others.

Badran, R. I.; Masri, Dana Al [Physics Department, Faculty of Sciences, The Hashemite University, Zarqa (Jordan)

2013-12-16T23:59:59.000Z

269

Percent Distribution  

Gasoline and Diesel Fuel Update (EIA)

. . Percent Distribution of Natural Gas Supply and Disposition by State, 1996 Table State Estimated Proved Reserves (dry) Marketed Production Total Consumption Alabama................................................................... 3.02 2.69 1.48 Alaska ...................................................................... 5.58 2.43 2.04 Arizona..................................................................... NA 0 0.55 Arkansas.................................................................. 0.88 1.12 1.23 California.................................................................. 1.25 1.45 8.23 Colorado .................................................................. 4.63 2.90 1.40 Connecticut.............................................................. 0 0 0.58 D.C...........................................................................

270

Distributed Generation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Untapped Value of Backup Generation Untapped Value of Backup Generation While new guidelines and regulations such as IEEE (Institute of Electrical and Electronics Engineers) 1547 have come a long way in addressing interconnection standards for distributed generation, utilities have largely overlooked the untapped potential of these resources. Under certain conditions, these units (primarily backup generators) represent a significant source of power that can deliver utility services at lower costs than traditional centralized solutions. These backup generators exist today in large numbers and provide utilities with another option to reduce peak load, relieve transmission congestion, and improve power reliability. Backup generation is widely deployed across the United States. Carnegie Mellon's Electricity

271

Diffractive parton distributions from perturbative QCD  

E-Print Network [OSTI]

The asymptotic collinear factorisation theorem, which holds for diffractive deep-inelastic scattering, has important modifications in the sub-asymptotic HERA regime. We use perturbative QCD to quantify these modifications. The diffractive parton distributions are shown to satisfy an inhomogeneous evolution equation. We emphasise that it is necessary to include both the gluonic and sea-quark t-channel components of the perturbative Pomeron. The corresponding Pomeron-to-parton splitting functions are derived in the Appendix.

Martin, A D; Watt, G

2005-01-01T23:59:59.000Z

272

Diffractive parton distributions from perturbative QCD  

E-Print Network [OSTI]

The asymptotic collinear factorisation theorem, which holds for diffractive deep-inelastic scattering, has important modifications in the sub-asymptotic HERA regime. We use perturbative QCD to quantify these modifications. The diffractive parton distributions are shown to satisfy an inhomogeneous evolution equation. We emphasise that it is necessary to include both the gluonic and sea-quark t-channel components of the perturbative Pomeron. The corresponding Pomeron-to-parton splitting functions are derived in the Appendix.

A. D. Martin; M. G. Ryskin; G. Watt

2005-04-15T23:59:59.000Z

273

Characterization of Metallurgical Chars by Small Angle Neutron Scattering  

Science Journals Connector (OSTI)

Characterization of Metallurgical Chars by Small Angle Neutron Scattering ... Small angle scattering measures the intensity I(q) of scattered neutrons as a function of scattering angle ? from the input beam, or alternatively, as a function of the scattering vector q:? q = |q| = (4?/?) sin(?/2), where ? is the wavelength of the incident wave. ...

I. Snook; I. Yarovsky; H. J. M. Hanley; M. Y. Lin; D. Mainwaring; H. Rogers; P. Zulli

2002-08-06T23:59:59.000Z

274

Scattering of Neutrons in Polycrystals  

Science Journals Connector (OSTI)

Although elastic and first-order inelastic cross sections for a neutron against a Debye crystal have already been determined, expressions for higher order inelastic collisions have not been calculated, and would be very complex for the Debye model. The calculation of the total inelastic cross section involving the emission of an arbitrarily large number of phonons is here presented for a neutron against an Einstein polycrystal. The result, as one would expect, is essentially the same as that given by Fermi for amorphous scatterers, except at high neutron energies where we have calculated the cross section for the ejection of the struck nucleus from its lattice. The coherent elastic cross section is also determined; it is important for energies as high as 1 volt, and does not differ appreciably from that previously calculated for a Debye crystal. The total cross section, the sum of the coherent and incoherent parts, is compared with the experimental data on beryllium.

R. J. Finkelstein

1947-11-15T23:59:59.000Z

275

Scattering of Neutrons by Deuterons  

Science Journals Connector (OSTI)

The elastic scattering of neutrons by deuterons is considered for energies small enough so that only the l=0 part of the incident wave is different from the corresponding part of a plane wave. The Breit-Feenberg Hamiltonian is used, assuming the same potential between all pairs of particles. Any possible polarization of the deuteron by the neutron is neglected, although the individual particles in the deuteron are taken into account by an approximate method. This method is capable of including exchange between the two neutrons. When the exchange term is included, the theory gives a cross section for thermal neutrons two to three times greater than observed; the cross section for 2.5 Mev neutrons is slightly greater than observed.

L. I. Schiff

1937-08-01T23:59:59.000Z

276

Neutron Scattering on Frustrated Magnets  

Science Journals Connector (OSTI)

Frustration denotes the inability of a system to satisfy all pairwise interactions and enables a large variety of fascinating ground states that depend on the very details of the interactions involved. The focus will be on neutron scattering studies of spinel compounds AB 2 X 4 . It is well known that the B?site ions form a pyrochlore lattice with inherent strong geometric frustration (GF). Among these compounds heavy fermion?like behaviour of LiV 2 O 4 and new kinds of magneto?elastic coupling phenomena in chromate spinels will be considered. Recently also the A?site spinels has been shown to be subject to strong frustration effects not only for the spin sector but also for the orbital and structural degrees of freedom. Corresponding ordering phenomena in MAl 2 O 4 ( M ?=? Mn Fe Co ) will be discussed.

A. Krimmel; V. Tsurkan; A. Loidl; H. Mutka; M. M. Koza

2008-01-01T23:59:59.000Z

277

Neutrino Beams for Scattering Experiment  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Options for Neutrino Scattering Measurements Options for Neutrino Scattering Measurements Draft Skeleton Table Beam Characteristics K2K CERN AD FNAL Debuncher FNAL Booster NuMI LE NuMI ME NuMI HE Peak E(nu) (GeV) X X ~2.5 1 3.5 7.5 13 Maximum E(nu) (GeV) (->1% peak rate) X X 8.9 3 50 50+ 50+ Nu(mu) CC Rate (per ton-year) X 1.4 0 5,000 210,000 1,100,000 2,000,000 Nubar(mu) CC Rate (per ton-year) X 3.4 ~18 (Time Separated) ~360 (Prompt) 1,000 21,000 32,000 20,000 Nu(e) CC Rate (per ton-year) X 0 0 1 2,300 9,500 12,000 Nubar(e) CC Rate (per ton-year) X 0.4 ~18 (Time Separated) 0.5 630 660 600 Flux uncertainty X X 10% 10% 20% 20% 20% QE events / 100 ton-years X 169 nubar(mu) 47 nu(mu) 17 nubar(e) 525 nubar(e) 500,000 nu(mu) 100,000 nu(mu) X X X Floor space (m**2) X X New Hall New Hall 20 x 2.5 20 x 2.5 20 x 2.5 Run Type X X Parasitic Parasitic Parasitic Parasitic Parasitic

278

CP violation in neutrino–photon scattering  

Science Journals Connector (OSTI)

It is shown that effects of CP violation arise in neutrino–photon scattering. Several CP-violating ?? reactions are considered within the Standard Model and predictions for some observables are made. It is emphasized that neutrino–photon scattering may provide an experimental tool for testing the scale dependence of CP violation.

I Alikhanov

2014-01-01T23:59:59.000Z

279

Neutron-Proton Scattering at Small Angles  

Science Journals Connector (OSTI)

24 May 1955 research-article Neutron-Proton Scattering at Small Angles...Thresher R. G. P. Voss R. Wilson Neutron-proton scattering has been measured from 6 to 61 5 degrees c.m. for neutrons of effective energy 105 3 and 137 5...

1955-01-01T23:59:59.000Z

280

Neutrino proton scattering and the isosinglet term  

SciTech Connect (OSTI)

Elastic neutrino proton scattering is sensitive to the SU(3) axial isosinglet term which is in turn dependent on the strangeness content of the proton. The uncertainties in the analysis of a neutrino proton elastic scattering experiment are discussed, and an experiment which is insensitive to many of the difficulties of the previous experiment is described.

White, D.H.

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Neutron scattering studies of materials under pressure  

Science Journals Connector (OSTI)

A review of experimental techniques used in the study of materials under applied pressure by neutron scattering is given along with a discussion of the amount of information that can be obtained from various pressure conditions. Some experimental results are presented to illustrate both the feasibility and the interest of elastic and inelastic neutron scattering measurements of materials under pressure.

C. Vettier

1982-01-01T23:59:59.000Z

282

Neutron scattering studies of lac repressor  

Science Journals Connector (OSTI)

... 1. Two parameters were obtained from the Guinier plots-a radius of gyration of excess scattering length density, RG, and the ... length density, RG, and the scattered intensity extrapolated to zero angle (//C)o, which is related to the MW ...

M. Charlier; J. C. Maurizot; G. Zaccai

1980-07-24T23:59:59.000Z

283

Percent Distribution  

Gasoline and Diesel Fuel Update (EIA)

. . Percent Distribution of Natural Gas Delivered to Consumers by State, 1996 Table State Residential Commercial Industrial Vehicle Fuel Electric Utilities Alabama..................................... 1.08 0.92 2.27 0.08 0.23 Alaska ........................................ 0.31 0.87 0.85 - 1.16 Arizona....................................... 0.53 0.92 0.30 3.91 0.70 Arkansas.................................... 0.88 0.98 1.59 0.11 1.24 California.................................... 9.03 7.44 7.82 43.11 11.64 Colorado .................................... 2.12 2.18 0.94 0.58 0.20 Connecticut................................ 0.84 1.26 0.37 1.08 0.38 D.C............................................. 0.33 0.52 - 0.21 - Delaware.................................... 0.19 0.21 0.16 0.04 0.86 Florida........................................

284

Distribution Category:  

Office of Legacy Management (LM)

- - Distribution Category: Remedial Action and Decommissioning Program (UC-70A) DOE/EV-0005/48 ANL-OHS/HP-84-104 ARGONNE NATIONAL LABORATORY 9700 South Cass Avenue Argonne, Illinois 60439 FORMERLY UTILIZED MXD/AEC SITES REMEDIAL ACTION PROGRAM RADIOLOGICAL SURVEY OF THE HARSHAW CHEMICAL COMPANY CLEVELAND. OHIO Prepared by R. A. Wynveen Associate Division Director, OHS W. H. Smith Senior Health Physicist C. M. Sholeen Health Physicist A. L. Justus Health Physicist K. F. Flynn Health Physicist Radiological Survey Group Health Physics Section Occupational Health and Safety Division April 1984 Work Performed under Budget Activity DOE KN-03-60-40 and ANL 73706 iii PREFACE AND EXECUTIVE SUMMARY This is one in a series of reports resulting from a program initiated

285

Strong coupling effects in near-barrier heavy-ion elastic scattering  

E-Print Network [OSTI]

Accurate elastic scattering angular distribution data measured at bombarding energies just above the Coulomb barrier have shapes that can markedly differ from or be the same as the expected classical Fresnel scattering pattern depending on the structure of the projectile, the target or both. Examples are given such as 18O + 184W and 16O + 148,152Sm where the expected rise above Rutherford scattering due to Coulomb-nuclear interference is damped by coupling to the target excited states, and the extreme case of 11Li scattering, where coupling to the 9Li + n + n continuum leads to an elastic scattering shape that cannot be reproduced by any standard optical model parameter set. The recent availability of high quality 6He, 11Li and 11Be data provides further examples of the influence that coupling effects can have on elastic scattering. Conditions for strong projectile-target coupling effects are presented with special emphasis on the importance of the beam-target charge combination being large enough to bring ab...

Keeley, N; Rusek, K

2014-01-01T23:59:59.000Z

286

Temperature Dependent Neutron Scattering Sections for Polyethylene  

E-Print Network [OSTI]

This note presents neutron scattering cross sections for polyethylene at 296 K, 77 K and 4 K derived from a new scattering kernel for neutron scattering off of hydrogen in polyethylene. The kernel was developed in ENDF-6 format as a set of S(alpha,beta) tables using the LEAPR module of the NJOY94 code package. The polyethylene density of states (from 0 to sub eV) adopted to derive the new kernel is presented. We compare our calculated room temperature total scattering cross sections and double differential cross sections at 232 meV at various angles with the available experimental data (at room temperature), and then extrapolate the calculations to lower temperatures (77K and 4K). The new temperature dependent scattering kernel gives a good quantitative fit to the available room temperature data and has a temperature dependence that is qualitatively consistent with thermodynamics.

Roger E. Hill; C. -Y. Liu

2003-09-05T23:59:59.000Z

287

Theory of Brillouin scattering from opaque media  

Science Journals Connector (OSTI)

The general theory of Brillouin scattering from the surfaces of opaque media is developed using a total field solution approach. Acoustical modes appropriate to a stress-free surface are found from solutions to the acoustical-wave equation and boundary conditions for a finite isotropic medium. Two light-scattering mechanisms, namely, the surface corrugation and bulk elasto-optical effects, were analyzed by deriving optical fields which satisfy both the acousto-optically driven wave equation and the electromagnetic boundary conditions. The special case for a metal of scattering by acoustically created conductivity fluctuations was also investigated in a similar way. The Brillouin spectrum was obtained by summing the scattering from the individual acoustical modes over the density of phonon states. Excellent agreement was obtained with experiment for Brillouin scattering from the metals gallium (liquid) and aluminum (solid).

N. L. Rowell and G. I. Stegeman

1978-09-15T23:59:59.000Z

288

Rotational Correlation Function of Spherical Rotors and Neutron Scattering  

Science Journals Connector (OSTI)

......Function of Spherical Rotors and Neutron Scattering Juichiro Hama Tuto Nakamura...Correlation Effect on the Slow Neutron Scattering by Polyatomic Molecules with...A. , Kowalska A. Thermal Neutron Scattering-Egelstaff P. A., ed......

Juichiro Hama; Tuto Nakamura

1971-12-01T23:59:59.000Z

289

Diffuse Neutron Scattering from Crystal Imperfections [and Discussion  

Science Journals Connector (OSTI)

...1980 research-article Diffuse Neutron Scattering from Crystal Imperfections...years has been the small angle scattering centred on 000. Examples are...comparison with small angle neutron scattering, much less work has been done...

1980-01-01T23:59:59.000Z

290

UNIVERSITY OF CALIFORNIA Inelastic Neutron Scattering Study of the  

E-Print Network [OSTI]

UNIVERSITY OF CALIFORNIA IRVINE Inelastic Neutron Scattering Study of the Intermediate Valence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Inelastic Neutron Scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.a Neutron Scattering Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.b

Lawrence, Jon

291

Neutron Scattering from Liquid Helium at Large Momentum Transfer  

Science Journals Connector (OSTI)

......letter Letters to the Editor Neutron Scattering from Liquid Helium at Large...Vol. 46 (1971), No. 1 Neutron Scattering from Liquid Helium at Large...Feynman diagram for the elastic scattering of a neutron from liquid helium, where......

Sigenobu Sunakawa; Kazuo Okajima; Kiyohisa Matsuda

1971-07-01T23:59:59.000Z

292

Slow Neutron Scattering and Space-Time Correlation Functions  

Science Journals Connector (OSTI)

......research-article Articles Slow Neutron Scattering and Space-Time Correlation...Osaka The cross section for neutron scattering is studied in the light of...Quasi-Classical Theory of Slow Neutron Scattering Takeo Nishigori and Sigenobu......

Sigenobu Sunakawa; Shuichiro Yamasaki; Takeo Nishigori

1967-06-01T23:59:59.000Z

293

Fully portable, highly flexible dilution refrigerator systems for neutron scattering  

E-Print Network [OSTI]

775 Fully portable, highly flexible dilution refrigerator systems for neutron scattering P. A systems developed specifically for neutron scattering environ- ments. The refrigerators are completely relatively recently however, the lowest temperatures available in almost all neutron scattering laboratories

Boyer, Edmond

294

Quasi-Classical Theory of Slow Neutron Scattering  

Science Journals Connector (OSTI)

......Quasi-Classical Theory of Slow Neutron Scattering Takeo Nishigori Sigenobu...quasi-classical formula of the scattering cross section of a slow neutron is proposed. The formula...Approximation for Slow Neutron Scattering Takeo Nishigori References......

Takeo Nishigori; Sigenobu Sunakawa

1969-03-01T23:59:59.000Z

295

Neutron scattering study of human serum low density lipoprotein  

Science Journals Connector (OSTI)

Neutron scattering study of human serum low density...human serum have been determined by neutron scattering. From measurements in various H2O...protein emerging from the lipid core. Neutron scattering study of human serum low density...

H B Stuhrmann; A Tardieu; L Mateu; C Sardet; V Luzzati; L Aggerbeck; A M Scanu

1975-01-01T23:59:59.000Z

296

Small-angle neutron scattering and neutron reflectometry  

Science Journals Connector (OSTI)

Diffraction methods, interpreted loosely, could be applied to the techniques of wide-angle X-ray scattering, small-angle X-ray scattering, electron diffraction, small-angle neutron scattering, small-angle light s...

R. W. Richards

1993-01-01T23:59:59.000Z

297

Carrier-carrier scattering in the gain dynamics of InxGa1-xAs/AlyGa1-yAs diode lasers  

Science Journals Connector (OSTI)

Ultrafast optical nonlinearities in semiconductors play a central role in determining transient amplification and pulse-dependent gain saturation in diode lasers. Both carrier-phonon and carrier-carrier scattering are expected to determine the gain dynamics in these systems. We present a relaxation-time approximation model for carrier-carrier scattering in strained-layer lasers. The carrier-carrier scattering rates are determined using the quasiequilibrium distribution functions for a given background carrier density. The distribution function to which the photoexcited distribution relaxes is a Fermi-Dirac function where the chemical potential and temperature are self-consistently chosen so that both particle number and energy are conserved in the carrier-carrier scattering process. The relaxation approximation makes the problem an effective one-dimensional problem which can then be solved directly for the carrier distributions using an adaptive Runge-Kutta routine. This procedure is less computationally intensive than a full Monte Carlo simulation. The results show that the inclusion of carrier-carrier scattering improves previous results where only carrier-phonon scattering was included and that carrier-carrier scattering is necessary to produce heating of the carriers in the high-energy tails. © 1996 The American Physical Society.

G. D. Sanders; C.-K. Sun; B. Golubovic; J. G. Fujimoto; C. J. Stanton

1996-09-15T23:59:59.000Z

298

Elastic scattering of electrons from Ar and Kr in the second-order eikonal approximation  

Science Journals Connector (OSTI)

We report the first application of Baker's second-order eikonal approximation (SOEA) to atomic collisions and compare the predictions of SOEA with those of Glauber's first-order eikonal approximation (FOEA). The SOEA takes into account amplitude modulation, in addition to phase modulation of the incoming plane wave. In the case of elastic scattering of electrons from argon and krypton, it is found that the second-order correction term influences to a large extent the angular distribution of scattered electrons. In the intermediate-and high-energy range it is seen that the SOEA gives much better agreement than the FOEA with the staticfield calculation of Fink and Yates.

A. C. Roy and N. C. Sil

1977-03-01T23:59:59.000Z

299

Structured x-ray beams from twisted electrons by inverse Compton scattering of laser light  

E-Print Network [OSTI]

The inverse Compton scattering of laser light on high-energetic twisted electrons is investigated with the aim to construct spatially structured x-ray beams. In particular, we analyze how the properties of the twisted electrons, such as the topological charge and aperture angle of the electron Bessel beam, affects the energy and angular distribution of scattered x-rays. We show that with suitably chosen initial twisted electron states one can synthesize tailor-made x-ray beam profiles with a well-defined spatial structure, in a way not possible with ordinary plane-wave electron beams.

Seipt, D; Fritzsche, S

2014-01-01T23:59:59.000Z

300

Folding model analysis of 240 MeV (6)Li elastic scattering on (116)Sn and inelastic scattering to low-lying states of (116)Sn  

E-Print Network [OSTI]

) where C, ?, ?, ? are parameters chosen for different density dependent functions. IV. DATA ANALYSIS AND DISCUSSION Elastic scattering data were fitted by the WS phenomeno- logical potential model and potentials derived from double folding. Fermi... distributions obtained from droplet model 054606-2 FOLDING MODEL ANALYSIS OF 240 MeV 6Li . . . PHYSICAL REVIEW C 76, 054606 (2007) TABLE I. Density parameters for the folding calculations. Fermi parameters c (half density radius) and a (diffuseness) are given...

Chen, X.; Lui, Y. -W; Clark, H. L.; Tokimoto, Y.; Youngblood, David H.

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Neutron scattering length of lithium and boron and their isotopes  

Science Journals Connector (OSTI)

Coherent neutron scattering lengths and free cross sections were measured in order to determine the spin dependent scattering lengths of the isotopes of Li and B.

L. Koester; K. Knopf; W. Waschkowski

1983-01-01T23:59:59.000Z

302

On the microscopic origin of light scattering in tissue  

Science Journals Connector (OSTI)

Understanding the nature of light scattering within tissue is a crucial issue for development of medical imaging techniques. Microscopic measurements of static light-scattering...

Kaplan, Peter; Weissman, Jesse; Hancewicz, Tom; Popp, Alois; Weitz, David

303

11th LANSCE School on Neutron Scattering | Lecturers  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laboratory Rex Hjelm Rex P. Hjelm is the Instrument Scientist for the small-angle neutron scattering instrument, LQD, at the Lujan Neutron Scattering Center of LANSCE at...

304

11th LANSCE School on Neutron Scattering | About the School  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

students calculate results About the LANSCE School on Neutron Scattering The annual Los Alamos Neutron Science Center (LANSCE) School on Neutron Scattering is 9- to 10-day school...

305

2012 LANSCE Neutron Scattering School | Los Alamos National Laboratory  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2011 LANSCE Neutron Scattering School LANSCE 2011 LANSCE Neutron Scattering School Home NSS 2011 About the School Lecturers Hands-On Experiments Quick Links Application Schedule...

306

Neutron Compton scattering from hydrogen and perovskite oxide interfaces.  

E-Print Network [OSTI]

??In this thesis we investigate two independent topics: neutron Compton scattering from hydrogen and perovskite oxide interfaces. Part one is an investigation of the scattering… (more)

Lemon, Christopher P.

2010-01-01T23:59:59.000Z

307

2012 LANSCE Neutron Scattering School | Los Alamos National Laboratory  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2012 LANSCE Neutron Scattering School LANSCE 2012 LANSCE Neutron Scattering School Home About the School Hands-On Experiments Quick Links Application - Closed Schedule Poster...

308

Application of Neutron Imaging and Scattering to Fluid Flow and...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Application of Neutron Imaging and Scattering to Fluid Flow and Fracture in EGS Environments Application of Neutron Imaging and Scattering to Fluid Flow and Fracture in EGS...

309

International Conference on Neutron Scattering 2005 Darling Harbour. Sydney. Australia  

E-Print Network [OSTI]

International Conference on Neutron Scattering 2005 Darling Harbour. Sydney. Australia 27 November, Hillerød, Denmark Combined application of small-angle neutron scattering and oscillatory shear

310

Manuel Lujan Jr. Neutron Scattering Center Los Alamos Neutron...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2013 LANSCE School on Neutron Scattering Geosciences & Materials in Extreme Environments Manuel Lujan Jr. Neutron Scattering Center Los Alamos Neutron Science Center Los Alamos...

311

Incoherent neutron scattering from multi-element materials  

Science Journals Connector (OSTI)

The differences and distinguishing characteristics of incoherent scattering vis-à-vis diffuse coherent scattering due to atomic disorder are delineated and demonstrated experimentally.

Glinka, C.J.

2011-04-02T23:59:59.000Z

312

Attosecond neutron Compton scattering from protons  

E-Print Network [OSTI]

The effect of "anomalous" scattering of neutrons and electrons from protons in the electron-volt energy-transfer range is considered, and related experimental results are mentioned. A recent independent confirmation of this effect with a new data analysis procedure is presented. Due to the very short characteristic scattering time, there is no well defined separation of time scales of electronic and protonic motions. An outline of a proposed theoretical interpretation is presented, which is based on the fact that scattering protons represent \\textit{open} quantum systems, thus being subject to decoherence.

C. Aris Chatzidimitriou-Dreismann

2007-02-01T23:59:59.000Z

313

A Multi-Level Grid Interactive Bi-directional AC/DC-DC/AC Converter and a Hybrid Battery/Ultra-capacitor Energy Storage System with Integrated Magnetics for Plug-in Hybrid Electric Vehicles  

SciTech Connect (OSTI)

This study presents a bi-directional multi-level power electronic interface for the grid interactions of plug-in hybrid electric vehicles (PHEVs) as well as a novel bi-directional power electronic converter for the combined operation of battery/ultracapacitor hybrid energy storage systems (ESS). The grid interface converter enables beneficial vehicle-to-grid (V2G) interactions in a high power quality and grid friendly manner; i.e, the grid interface converter ensures that all power delivered to/from grid has unity power factor and almost zero current harmonics. The power electronic converter that provides the combined operation of battery/ultra-capacitor system reduces the size and cost of the conventional ESS hybridization topologies while reducing the stress on the battery, prolonging the battery lifetime, and increasing the overall vehicle performance and efficiency. The combination of hybrid ESS is provided through an integrated magnetic structure that reduces the size and cost of the inductors of the ESS converters. Simulation and experimental results are included as prove of the concept presenting the different operation modes of the proposed converters.

Onar, Omer C [ORNL] [ORNL

2011-01-01T23:59:59.000Z

314

From Nuclei to Micro-structure: investigating intermediate length scales by small angle laser light scattering  

E-Print Network [OSTI]

Hard spheres are a well recognized model system of statistical physics and soft condensed matter. Their crystallization behaviour has been intensively studied at the structural length scale by Bragg light scattering and/or high resolution microscopy. We here present an improved light scattering apparatus capable to perform simultaneous measurements in the Bragg scattering regime and in the small angle regime. We give an account of its construction and demonstrate its performance for several examples of hard sphere and attractive hard sphere suspensions. Comparison of small angle to Bragg data allows a calibration of the sequence of events in time. We show how important complementary information can be gained from the small angle studies e.g. on the immediate environment of the growing crystals or the global scale crystallite distribution. We further demonstrate that processes occurring on larger length scales have a significant influence on the crystallization kinetics and the final micro-structure.

Richard Beyer; Markus Franke; Hans Joachim Schöpe; Eckhard Bartsch; Thomas Palberg

2014-12-02T23:59:59.000Z

315

A diagnosis of intense ion beam by CR-39 detectors analyzing the back scattered particles  

SciTech Connect (OSTI)

A new diagnosis method has been developed utilizing back scattered particles for high energy intense ion beams. The CR-39 detector mounted on the uniform back-scatterer was irradiated with {sup 4}He{sup 2+} ions with an energy 25 MeV/n, which is never recorded as etchable track in CR-39. We found that it is possible to diagnose by analyzing the etch pits on the rear surface of CR-39 that directly contacted on the back-scatterers. It turns out that most of etch pits in the rear surface are made by the backscattered particles by investigating the growth pattern of each etch pit with multi-step etching technique. This method allows simple diagnosis of the ion beam profile and intensity distribution in mixed radiation field such as laser-driven ion acceleration experiments.

Kanasaki, Masato; Yamauchi, Tomoya; Fukuda, Yuji; Sakaki, Hironao; Hori, Toshihiko; Tampo, Motonobu; Kurashima, Satoshi; Kamiya, Tomihiro; Oda, Keiji; Kondo, Kiminori [Graduate School of Maritime Sciences, Kobe University, Kobe 658-0022, Japan and Japan Atomic Energy Agency, Kizugawa, Kyoto 619-0215 (Japan); Graduate School of Maritime Sciences, Kobe University, Kobe 658-0022 (Japan); Japan Atomic Energy Agency, Kizugawa, Kyoto 619-0215 (Japan); Japan Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan); Graduate School of Maritime Sciences, Kobe University, Kobe 658-0022 (Japan); Japan Atomic Energy Agency, Kizugawa, Kyoto 619-0215 (Japan)

2012-07-11T23:59:59.000Z

316

Millimeter wave scattering and diffraction in 110 GHz air breakdown plasma  

SciTech Connect (OSTI)

We present measurements of the scattering, reflection, absorption, and transmission of a 1.5 MW, 110 GHz quasioptical gyrotron beam by a self-induced air breakdown plasma. The breakdown forms a periodic array of plasma filaments, oriented parallel to the incident electric field polarization that propagates toward the microwave source. For incident intensity of 3 MW/cm{sup 2}, calorimetric measurements show that as much as 45% of the full beam power is absorbed by the plasma, averaged over the pulse, 1% is reflected backward, and the remainder is transmitted and also scattered into a wide angular spread. We observe that approximately 10 times more power is scattered in the direction perpendicular to the filaments than parallel. The far-field angular distribution of transmitted power exhibits a diffraction pattern that changes throughout the 2-{mu}s life of the plasma.

Cook, Alan M.; Hummelt, Jason S.; Shapiro, Michael A.; Temkin, Richard J. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2013-04-15T23:59:59.000Z

317

Cross sections for electron scattering by propane in the low- and intermediate-energy ranges  

SciTech Connect (OSTI)

We present a joint theoretical-experimental study on electron scattering by propane (C{sub 3}H{sub 8}) in the low- and intermediate-energy ranges. Calculated elastic differential, integral, and momentum transfer as well as total (elastic + inelastic) and total absorption cross sections are reported for impact energies ranging from 2 to 500 eV. Also, experimental absolute elastic cross sections are reported in the 40- to 500-eV energy range. A complex optical potential is used to represent the electron-molecule interaction dynamics. A theoretical method based on the single-center-expansion close-coupling framework and corrected by the Pade approximant is used to solve the scattering equations. The experimental angular distributions of the scattered electrons are converted to absolute cross sections using the relative flow technique. The comparison of our calculated with our measured results, as well as with other experimental and theoretical data available in the literature, is encouraging.

Souza, G. L. C. de; Lee, M.-T.; Sanches, I. P.; Rawat, P.; Iga, I.; Santos, A. S. dos; Machado, L. E.; Sugohara, R. T.; Brescansin, L. M.; Homem, M. G. P.; Lucchese, R. R. [Departamento de Quimica, UFSCar, 13565-905 Sao Carlos, SP (Brazil); Departamento de Fisica, UFSCar, 13565-905 Sao Carlos, SP (Brazil); Instituto de Fisica 'Gleb Wataghin', UNICAMP, 13083-970 Campinas, SP (Brazil); Departamento de Fisica, UFSC, 88010-970 Florianopolis, SC (Brazil); Department of Chemistry, Texas A and M University, College Station, Texas 7784-3255 (United States)

2010-07-15T23:59:59.000Z

318

Spin observables in nucleon-nucleus scattering  

SciTech Connect (OSTI)

The curse of inelastic nucleon scattering and charge exchange has always been the enormous complexity of the nucleon-nucleon (N-N) interaction. This complexity, however, can also be viewed as the ultimate promise of nucleons as probes of nuclear structure. Given an adequate theoretical basis, inelastic nucleon scattering is capable of providing information not obtainable with other probes. Recently a revolution of experimental technique has taken place that makes it desirable to re-examine the question of what physics is ultimately obtainable from inelastic nucleon scattering. It is now feasible to perform complete polarization transfer (PT) experiments for inelastic proton scattering with high efficiency and excellent energy resolution. Programs to measure PT obsevables are underway at several laboratories, and results are beginning to appear. Objectives of this presentation are to examine how such experiments are done, and what physics is presently obtained and may ultimately be learned from them.

Moss, J.M.

1982-01-01T23:59:59.000Z

319

What Does a Scattering Pattern Tell US?  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

e iwt Phase difference Phase difference S e i (ri Q) A(DK) fi A(Q) Fourier Transform ( ri ) DK Q 4p sin(q) l Lensless Imaging Sample Space Scattering Space sample...

320

Scattering theory without large-distance asymptotics  

E-Print Network [OSTI]

In conventional scattering theory, to obtain an explicit result, one imposes a precondition that the distance between target and observer is infinite. With the help of this precondition, one can asymptotically replace the Hankel function and the Bessel function with the sine functions so that one can achieve an explicit result. Nevertheless, after such a treatment, the information of the distance between target and observer is inevitably lost. In this paper, we show that such a precondition is not necessary: without losing any information of distance, one can still obtain an explicit result of a scattering rigorously. In other words, we give an rigorous explicit scattering result which contains the information of distance between target and observer. We show that at a finite distance, a modification factor --- the Bessel polynomial --- appears in the scattering amplitude, and, consequently, the cross section depends on the distance, the outgoing wave-front surface is no longer a sphere, and, besides the phase...

Liu, Tong; Dai, Wu-Sheng

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Orthopositronium-orthopositronium scattering at medium energies  

SciTech Connect (OSTI)

The scattering of ortho-positronium (o-Ps) atoms has been investigated using the first Born approximation (FBA) and Born-Oppenheimer (B-O) model at medium energies. The angle integrated total elastic cross sections of o-Ps-o-Ps scattering have been reported. Apart from this, the inelastic cross sections for discrete excitations (principal quantum number, n{<=}3) of the single and both the Ps atoms as well as single and double Ps atom ionization have also been obtained. We have also predicted the total cross section of o-Ps-o-Ps scattering by adding all these partial cross sections. The first Born and B-O scattering amplitudes have also been evaluated using partial wave technique. It has been noticed that odd values of the partial wave B-O amplitude vanishes for even parity transitions and vice versa. To the best of our knowledge, this feature has not been noticed for other systems.

Chakraborty, Sumana; Ghosh, A.S. [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700 032 (India); Kumari, Kiran [Department of Physics, R N College, Hajipur (Vaishali), B R A Bihar University, Muzaffarpur, Bihar (India)

2005-08-15T23:59:59.000Z

322

Bragg scattering measurement of atmospheric plasma decay  

Science Journals Connector (OSTI)

The decay processes of the plasma layers generated by two intersecting microwave pulses in 1 torr dry air are investigated by Bragg scattering method. The results of measurement show that the electrons decay i...

Y. S. Zhang; S. P. Kuo

1991-04-01T23:59:59.000Z

323

Neutron-deuteron breakup and quasielastic scattering  

E-Print Network [OSTI]

Quasielastic scattering and deuteron breakup in the 200 MeV region is studied by impinging a pulsed neutron beam on a deuterium target at the Weapons Neutron Research facility at the Los Alamos Neutron Science Center. The ...

Ohlson, Alice Elisabeth

2009-01-01T23:59:59.000Z

324

Neutron Scattering and Ordering of Nuclear Spins  

Science Journals Connector (OSTI)

The ordering of nuclear spins takes place at extremely low temperatures because of the weakness of the interactions between their magnetic moments. Neutron scattering is the traditional and unique method to ... (...

M. Steiner

2004-06-01T23:59:59.000Z

325

Scattering Properties of Oriented Hexagonal Ice Crystals  

E-Print Network [OSTI]

To interpret the data from spaceborn lidar measurements, one must have a basic understanding of the backscattering of oriented ice particles. The conventional raytracing method is not applicable to the scattering of light by oriented particles...

Zhang, Feng

2010-01-14T23:59:59.000Z

326

Neutron scattering experiments on partially disordered materials  

Science Journals Connector (OSTI)

Neutron scattering methods to characterize intercalation compounds of layered conducting compounds are presented. It is shown that complex structural and chemical processes exist which must be understood before an ‘‘in depth’’ study of selected systems can be started.

C. Riekel

1982-01-01T23:59:59.000Z

327

Neutron scattering instrumentation at reactor based installations  

Science Journals Connector (OSTI)

During the past decade neutron scattering techniques have been applied to an increasingly wide range of scientific problems. Concurrently a number of substantial improvements of neutron scattering instrumentation have occurred to stimulate this trend. In this article several such developments which have occurred at reactor?based installations are described. Individual spectrometer components which are discussed in some detail include: neutron?optical devices such as guide tubes supermirrors and multilayer systems; neutronmonochromators with optimum reflectivity mosaic and focusing characteristics; position?sensitive detectors of several types; and equipment required for neutronpolarizationanalysis. Several novel spectrometers which have enhanced the role of neutron scattering during the past ten years are also described. These include spectrometers for small?angle scattering backscattering and neutron spin echo. An extensive bibliography is included which covers both early and more recent developments.

Roger Pynn

1984-01-01T23:59:59.000Z

328

Doppler effect in light scattering in liquids  

Science Journals Connector (OSTI)

The present work deals with the study of the state of polarisation of the three components observed in the spectrum of monochromatic light scattered by liquid formic and acetic acids, when examined with a Fabr...

B. V. Raghavendra Rao

1936-06-01T23:59:59.000Z

329

Branch length distribution in TREF fractionated polyethylene Ramnath Ramachandran a  

E-Print Network [OSTI]

Branch length distribution in TREF fractionated polyethylene Ramnath Ramachandran a , Gregory Keywords: Polyethylene Branching Neutron scattering a b s t r a c t Commercial polyethylene is typically and catalyst activity. Further, processing of polyethylene after polymerization may also result in changes

Beaucage, Gregory

330

13 - X-ray and Neutron Scattering  

Science Journals Connector (OSTI)

Abstract This chapter describes the use of neutrons and X-rays as probes in the study of structural and dynamic properties of metallic materials. Crystalline materials are characterized by their diffraction peaks related to their average crystallographic structure. In real crystals, locally displaced atoms and chemically (or isotopically for neutrons) different species may lead not only to changes of peak shapes and positions, but also to additional (diffuse) scattering between Bragg peak, including scattering around the primary beam (small-angle scattering). All these features can be used to extract information about the state of a sample, its compositional and structural variations on a scale depending on the scattering, in static and time-resolved kinetic studies. Energy-resolved scattering also offers an insight into solid-state dynamics on a microscopic scale. Some of the most important methods will be described and illustrated by instructive examples. The presentation offers a combined view of neutron and X-ray scattering, with the necessary simplifications dictated by space limitations. The special properties of thermal neutrons and of hard X-rays (now widely available at synchrotron radiation sources), their mutual combination, and combinations with other methods, in particular electron microscopy, offer ample opportunity to better understand and control materials properties. After a brief introduction to scattering from real crystals and some general ideas about long-range strains and Bragg peaks, the vicinity of Bragg peaks (displacement scattering at large scattering angles), the scattering far away from Bragg peaks (chemical heterogeneities, short-range order), and, in greater detail, small-angle scattering (which is not sensitive to the extent of crystallinity, but to nanoscale variations of chemical composition and of magnetization, precipitation) will be described, along with classical and more recent applications related to short-range ordering and precipitation in bulk and nanostructured alloys. Some other fields are only briefly addressed (grazing-incidence studies of surfaces, radiography, absorption spectroscopies, coherent X-rays). The final section offers some information on the influence of defects on lattice dynamics and on (slow) diffusive motion in materials.

Gernot Kostorz

2014-01-01T23:59:59.000Z

331

Can one extract the pi-neutron scattering length from pi-deuteron scattering?  

E-Print Network [OSTI]

We give a prove of evidence that the original power counting by Weinberg can be applied to estimate the contributions of the operators contributing to the pi-deuteron scattering length. As a consequence, pi-deuteron observables can be used to extract neutron amplitudes--in case of pi-deuteron scattering this means that the pi-neutron scattering length can be extracted with high accuracy. This result is at variance with recent claims. We discuss the origin of this difference.

A. Nogga; C. Hanhart

2005-11-02T23:59:59.000Z

332

Coherent Neutrino Scattering and Stellar Collapse  

Science Journals Connector (OSTI)

Freedman has shown that coherency and the neutral current theory of neutrinos imply a scattering cross section for neutrinos off heavy nuclei proportional to the square of the atomic weight. The collapse of an iron-core star produces a hot neutron star surrounded by a thin iron layer. Because of the large scattering rate in the outer layer, neutrinos from the hot neutron core are able to accelerate the iron layer to above escape velocity.

James R. Wilson

1974-04-15T23:59:59.000Z

333

Quantum Energy Regression using Scattering Transforms  

E-Print Network [OSTI]

We present a novel approach to the regression of quantum mechanical energies based on a scattering transform of an intermediate electron density representation. A scattering transform is a deep convolution network computed with a cascade of multiscale wavelet transforms. It possesses appropriate invariant and stability properties for quantum energy regression. This new framework removes fundamental limitations of Coulomb matrix based energy regressions, and numerical experiments give state-of-the-art accuracy over planar molecules.

Hirn, Matthew; Mallat, Stephane

2015-01-01T23:59:59.000Z

334

A beam swinger for neutron scattering  

Science Journals Connector (OSTI)

A conceptual design is presented for a system that provides for varying the angle of incidence of neutron flux on a scattering target. This makes possible the use of long flight paths for time?of?flight spectroscopy of scattered neutrons. The system is also applicable to measurements of neutron induced charged particle reactions. Special emphasis is placed on the energy range of 50–200 MeV.

C. D. Goodman

1985-01-01T23:59:59.000Z

335

Inverse scattering with non-overdetermined data  

E-Print Network [OSTI]

Let $A(\\beta,\\alpha,k)$ be the scattering amplitude corresponding to a real-valued potential which vanishes outside of a bounded domain $D\\subset \\R^3$. The unit vector $\\alpha$ is the direction of the incident plane wave, the unit vector $\\beta$ is the direction of the scattered wave, $k>0$ is the wave number. The governing equation for the waves is $[\

A. G. Ramm

2009-06-17T23:59:59.000Z

336

Explicit spatial scattering for load balancing in conservatively synchronized parallel discrete-event simulations  

SciTech Connect (OSTI)

We re-examine the problem of load balancing in conservatively synchronized parallel, discrete-event simulations executed on high-performance computing clusters, focusing on simulations where computational and messaging load tend to be spatially clustered. Such domains are frequently characterized by the presence of geographic 'hot-spots' - regions that generate significantly more simulation events than others. Examples of such domains include simulation of urban regions, transportation networks and networks where interaction between entities is often constrained by physical proximity. Noting that in conservatively synchronized parallel simulations, the speed of execution of the simulation is determined by the slowest (i.e most heavily loaded) simulation process, we study different partitioning strategies in achieving equitable processor-load distribution in domains with spatially clustered load. In particular, we study the effectiveness of partitioning via spatial scattering to achieve optimal load balance. In this partitioning technique, nearby entities are explicitly assigned to different processors, thereby scattering the load across the cluster. This is motivated by two observations, namely, (i) since load is spatially clustered, spatial scattering should, intuitively, spread the load across the compute cluster, and (ii) in parallel simulations, equitable distribution of CPU load is a greater determinant of execution speed than message passing overhead. Through large-scale simulation experiments - both of abstracted and real simulation models - we observe that scatter partitioning, even with its greatly increased messaging overhead, significantly outperforms more conventional spatial partitioning techniques that seek to reduce messaging overhead. Further, even if hot-spots change over the course of the simulation, if the underlying feature of spatial clustering is retained, load continues to be balanced with spatial scattering leading us to the observation that spatial scattering can often obviate the need for dynamic load balancing.

Thulasidasan, Sunil [Los Alamos National Laboratory; Kasiviswanathan, Shiva [Los Alamos National Laboratory; Eidenbenz, Stephan [Los Alamos National Laboratory; Romero, Philip [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

337

Small Angle X-Ray Scattering Detector  

DOE Patents [OSTI]

A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., q.sub.max /q.sub.min.congruent.100.

Hessler, Jan P. (Downers Grove, IL)

2004-06-15T23:59:59.000Z

338

Toward improved photon-atom scattering predictions  

SciTech Connect (OSTI)

Photon-atom scattering is important in a variety of applications, but scattering from a composite system depends on the accurate characterization of the scattering from an isolated atom or ion. We have been examining the validity of simpler approximations of elastic scattering in the light of second-order S-matrix theory. Partitioning the many-body amplitude into Rayleigh and Delbrueck components, processes beyond photoionization contribute. Subtracted cross sections for bound-bound atomic transitions, bound pair annihilation, and bound pair production are required in anomalous scattering factors for: (1) convergence of the dispersion integral; (2) agreement with predictions of the more sophisticated S-matrix approach; (3) satisfying the Thomas-Reiche-Kuhn sum rule. New accurate tabulations of anomalous scattering factors have been prepared for all Z, for energies 0--10,000 keV, within the independent particle approximation (IPA) using a Dirac-Slater model of the atom. Separately, experimental atomic photoabsorption threshold information has been used to modify these IPA predictions for improved comparison with experiment.

Kissel, L.

1994-10-21T23:59:59.000Z

339

Glassy Dynamics of Polystyrene by Quasielastic Neutron Scattering  

Science Journals Connector (OSTI)

Glassy Dynamics of Polystyrene by Quasielastic Neutron Scattering ... The ratio of coherent to total scattered intensities(25) has also been included on the rhs-axis of Figure 3 (crosses). ... It is introduced as the long-time limit of the intermediate scattering function and it is related to the region of the space accessible to the scatters. ...

S. Arrese-Igor; A. Arbe; B. Frick; J. Colmenero

2011-03-28T23:59:59.000Z

340

Neutron scattering at high pressure D. B. McWhan  

E-Print Network [OSTI]

715 Neutron scattering at high pressure D. B. McWhan Room 1D-234, Murray Hill, New Jersey 07974, U scattering at steady-state and pulsed sources are reviewed. The pressure cells available at most neutron 10 GPa have been made. For elastic scattering, a comparison is made between neutron scattering and X

Paris-Sud XI, Université de

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341

Neutron and X-ray Scattering Study of Magnetic Manganites  

E-Print Network [OSTI]

Neutron and X-ray Scattering Study of Magnetic Manganites Graeme Eoin Johnstone A Thesis submitted are performed using a variety of neutron scattering and x-ray scattering techniques. The electronic ground for analysing the results of the polarised neutron scattering experiment. There are a large number of people who

Boothroyd, Andrew

342

The Linear Sampling Method in Inverse Electromagnetic Scattering  

E-Print Network [OSTI]

Scatterer: Two Balls . . . . . . . . 50 3.5.2 The Teapot . . . . . . . . . . . . . . . . . . . . . . . 52 3

Cakoni, Fioralba

343

Electron scattering in isotonic chains as a probe of the proton shell structure of unstable nuclei  

E-Print Network [OSTI]

Electron scattering on unstable nuclei is planned in future facilities of the GSI and RIKEN upgrades. Motivated by this fact, we study theoretical predictions for elastic electron scattering in the N=82, N=50, and N=14 isotonic chains from very proton-deficient to very proton-rich isotones. We compute the scattering observables by performing Dirac partial-wave calculations. The charge density of the nucleus is obtained with a covariant nuclear mean-field model that accounts for the low-energy electromagnetic structure of the nucleon. For the discussion of the dependence of scattering observables at low-momentum transfer on the gross properties of the charge density, we fit Helm model distributions to the self-consistent mean-field densities. We find that the changes shown by the electric charge form factor along each isotonic chain are strongly correlated with the underlying proton shell structure of the isotones. We conclude that elastic electron scattering experiments in isotones can provide valuable information about the filling order and occupation of the single-particle levels of protons.

X. Roca-Maza; M. Centelles; F. Salvat; X. Viñas

2012-07-06T23:59:59.000Z

344

Electron scattering in isotonic chains as a probe of the proton shell structure of unstable nuclei  

E-Print Network [OSTI]

Electron scattering on unstable nuclei is planned in future facilities of the GSI and RIKEN upgrades. Motivated by this fact, we study theoretical predictions for elastic electron scattering in the N=82, N=50, and N=14 isotonic chains from very proton-deficient to very proton-rich isotones. We compute the scattering observables by performing Dirac partial-wave calculations. The charge density of the nucleus is obtained with a covariant nuclear mean-field model that accounts for the low-energy electromagnetic structure of the nucleon. For the discussion of the dependence of scattering observables at low-momentum transfer on the gross properties of the charge density, we fit Helm model distributions to the self-consistent mean-field densities. We find that the changes shown by the electric charge form factor along each isotonic chain are strongly correlated with the underlying proton shell structure of the isotones. We conclude that elastic electron scattering experiments in isotones can provide valuable inform...

Roca-Maza, X; Salvat, F; Viñas, X

2012-01-01T23:59:59.000Z

345

Study on generating of thermal neutron scattering cross sections for LiH  

SciTech Connect (OSTI)

LiH is designated as a promising moderator and shielding material because of its low density, high melting point and large fraction of H atoms. However, lack of the thermal neutron cross sections of LiH makes numerical calculation deviate from experimental data to some extent. As a result, it is necessary to study LiH thermal kernel effect. The phonon property of LiH has been investigated by first-principles calculations using the plane-wave pseudo potential method with CASTEP code. The scattering law and the thermal neutron scattering cross sections for Li and H have been generated using this distribution. The results have been compared with zirconium hydride data. The GASKET and NJOY/LEAPR codes have been used in the calculation of scattering law, whose results have been compared with the reference; the discrepancy mainly comes from phonon spectrums and its expansion. LEAPR had the capability to compute scattering through larger energy and momentum transfers than GASKET did. By studying LiH phonon spectrum and constructing the model of LiH thermal kernel and scattering matrix, the ACE format LiH thermal neutron cross sections for MCNP software could be made and used for reactor Neutronics calculation. (authors)

Wang, L.; Jiang, X.; Zhao, Z.; Chen, L. [Northwest Institute of Nuclear Technology, Xi'an 710024 (China)

2013-07-01T23:59:59.000Z

346

Neutron scattering and magnetic studies of ferrihydrite nanoparticles  

Science Journals Connector (OSTI)

Magnetic properties of two-line ferrihydrite (FeOOD?nD2O) nanoparticles with an average size ?4 nm are investigated using neutron scattering and magnetometry. Comparison of the neutron scattering and x-ray diffraction patterns identifies the (002) peak at Q=1.3 Å-1 as predominantly magnetic. The intensity of this peak, measured from 10 to 450 K, decreases almost linearly with temperature until 350 K, becoming temperature independent above 350 K. From this, TN?350 K is identified to be the ordering temperature of the core spins of the nanoparticles. The width of the line is temperature independent, yielding a magnetic coherence length?particle size. The temperature variations (5–300 K) of the initial susceptibility ? for the field-cooled (FC) and zero-field-cooled (ZFC) cases yield a peak at Tp(m)?65 K, below which ?(FC)>?(ZFC). For T>Tp(m), the variation of ?-1 vs T is analyzed in terms of the model of El-Hilo et al., involving particle-size distribution and interparticle interactions, and substantial interparticle interactions are inferred. Following the observations in ferritin, the field dependence of the magnetization M for T>Tp(m) is analyzed in terms of the modified Langevin variation: M=MoL(?pH/kT)+?aH, where ?p is the magnetic moment/particle. The fit at 100 K yields ?p?250 ?B, consistent with the theoretical estimates based on uncompensated surface spins of Fe3+.

M. S. Seehra; V. S. Babu; A. Manivannan; J. W. Lynn

2000-02-01T23:59:59.000Z

347

Scattering of Slow Neutrons by a Liquid  

Science Journals Connector (OSTI)

The differential cross section for coherent scattering of thermal neutrons by a liquid is given in general by the Fourier transform of a time-displaced radial density function. It is suggested here that, to an adequate degree of approximation, this time-displaced function can be expressed as a convolution of the ordinary radial density function with a self-diffusion function describing the wandering of an atom from an arbitrary initial position. The neutron scattering cross section then becomes the product of the Fourier transforms of these two functions. One of the transforms is the differential cross section for x-ray scattering and describes interference effects, the other governs the energy changes upon scattering. In this development the scatterer can be treated either quantum mechanically or classically. Recoil effects are not provided by the classical treatment, but this is a significant deficiency only in liquids of low atomic weight. Several models for calculating the self-diffusion function are considered, and from these it is suggested that a Gaussian function with a time-dependent width is a reasonable approximation for the case of a simple liquid. The principal features of the width are deduced. Quantization of the scatterer effects the width at small times. At large times the width depends only on the coefficient of self-diffusion of the liquid, and inelastic scattering is suggested as a means of determining this coefficient, as well as other features of atomic movement. The accuracy of the static approximation for determining liquid structures by neutron diffraction is assessed by considering the typical case of liquid lead near its melting point, and is found to be moderately good. The extension of the entire formalism to the case of polyatomic liquids is outlined.

George H. Vineyard

1958-06-01T23:59:59.000Z

348

Patterns of authors' information scattering: towards a causal explanation of information scattering from a scholarly information-seeking behavior perspective  

Science Journals Connector (OSTI)

This study primarily aims to reveal the worldwide patterns of authors' information scattering through illustrating the possible differences among authors based on subject, country, geographic region, institution, economic and scientific level factors. ... Keywords: Authors' patterns of information scattering, Bradford's law, Information scattering, Information scattering explanation, Scholarly information-seeking behavior, Scholarly journal usage

Zahed Bigdeli; Morteza Kokabi; Gholam Reza Rajabi; Ali Gazni

2013-07-01T23:59:59.000Z

349

NEUTRON: a program for computing phonon extinction rules of inelastic neutron scattering and thermal diffuse scattering experiments  

Science Journals Connector (OSTI)

NEUTRON is a program for the determination of phonon extinction rules in inelastic neutron scattering experiments.

Kirov, A.K.

2003-07-19T23:59:59.000Z

350

Absorption and Scattering When we have both variations in both absorption and scattering, the solution to the  

E-Print Network [OSTI]

Chapter 6 Absorption and Scattering When we have both variations in both absorption and scattering of absorption and scatttering. 6.1 Simulation Results For the following simulationsthe forward data were of the simulation. #12;Absorption and Scattering 107 We have reconstructed images of scattering and absorption

351

Unifying distribution functions: some lesser known distributions  

E-Print Network [OSTI]

We show that there is a way to unify distribution functions that describe simultaneously a signal in space and (spatial) frequency. Probably the most known of them is the Wigner distribution function. Here we show how to unify functions of the Cohen class, Rihacek's complex energy function, Husimi and Glauber-Sudarshan distribution functions.

Moya-Cessa, J R; Berriel-Valdos, L R; Aguilar-Loreto, O; Barberis-Blostein, P

2008-01-01T23:59:59.000Z

352

The use of multiple-scattering data to enhance small-angle neutron scattering experiments  

Science Journals Connector (OSTI)

It is shown that SANS patterns from specimens of different thicknesses but otherwise identical not only provide information on the shape and size of the scattering entity but also give absolute values of the scattering contrast between particles responsible for SANS and the matrix. No separate calibration of the incident beam is required.

Sabine, T.M.

1999-05-01T23:59:59.000Z

353

A Bayesian approach to removal of incoherent scattering from neutron total-scattering data  

Science Journals Connector (OSTI)

A Bayesian approach for subtraction of incoherent scattering from neutron total-scattering data has been developed and implemented in an open-source software package. The approach has been tested using both simulated and experimental data collected on different types of samples.

Gagin, A.

2014-11-28T23:59:59.000Z

354

Resonant impurity scattering and electron-phonon scattering in the electrical resistivity of Cr thin films  

E-Print Network [OSTI]

Resonant impurity scattering and electron-phonon scattering in the electrical resistivity of Cr The resistivity as a function of temperature from 0.6 to 300 K for epitaxial and polycrystalline Cr thin films residual resistivity up to 400 cm and a minimum at low temperatures below 100 K . This is strong

Hellman, Frances

355

Inclusion of Scatter in HADES: Final Report  

SciTech Connect (OSTI)

Covert nuclear attack is one of the foremost threats facing the United States and is a primary focus of the War on Terror. The Domestic Nuclear Detection Office (DNDO), within the Department of Homeland Security (DHS), is chartered to develop, and improve domestic systems to detect and interdict smuggling for the illicit use of a nuclear explosive device, fissile material or radiologica1 material. The CAARS (Cargo Advanced Automated Radiography System) program is a major part of the DHS effort to enhance US security by harnessing cutting-edge technologies to detect radiological and nuclear threats at points of entry to the United States. DNDO has selected vendors to develop complete radiographic systems. It is crucial that the initial design and testing concepts for the systems be validated and compared prior to the substantial efforts to build and deploy prototypes and subsequent large-scale production. An important aspect of these systems is the scatter which interferes with imaging. Monte Carlo codes, such as MCNP (X-5 Monte Carlo Team, 2005 Revision) allow scatter to be calculatied, but these calculations are very time consuming. It would be useful to have a fast scatter estimation algorithm in a fast ray tracing code. We have been extending the HADES ray-tracing radiographic simulation code to model vendor systems in a flexible and quick fashion and to use this tool to study a variety of questions involving system performance and the comparative value of surrogates. To enable this work, HADES has been linked to the BRL-CAD library (BRL-CAD Open Source Project, 2010), in order to enable the inclusion of complex CAD geometries in simulations, scanner geometries have been implemented in HADES, and the novel detector responses have been included in HADES. A major extension of HADES which has been required by this effort is the inclusion of scatter in these radiographic simulations. Ray tracing codes generally do not easily allow the inclusion of scatter, because these codes define a source and a grid of detector pixels and only compute the attenuation along rays between these points. Scatter is an extremely complex set of processes which can involve rays which change directions many times between the source and detector. Scatter from outside the field of view of the imaging system, as well as within the field of view, can have an important role in image formation. In this report, we will describe how we implemented a treatment of scatter in HADES. We begin with a discussion of how we define scatter in Section 2, followed by a description of how single Compton scatter is now included in HADES in Section 3. In Section 4 we report a set of verification tests against MCNP and tests of how the technique scales with image size, number of scatters allowed and number of processors used in the calculations. In Section 5, we describe how we plan to extend this approach to other forms of scatter and conclude in Section 6. It should be emphasized that the purpose of this report is to show that a form of scatter has been implemented in HADES and has been verified against MCNP. Validation, the process of comparing simulation and experiment, is a future task.

Aufderheide, M B

2010-12-20T23:59:59.000Z

356

Electron velocity distribution function in a plasma with temperature gradient and in the presence of suprathermal  

E-Print Network [OSTI]

Electron velocity distribution function in a plasma with temperature gradient and in the presence of suprathermal electrons: application to incoherent-scatter plasma lines P. Guio1 , J. Lilensten2 , W. Kofman2 arbitrary velocity distribution function with cylindrical symmetry along the magnetic ®eld. The electron

Paris-Sud XI, Université de

357

Proton-Proton Scattering at 5 Mev  

Science Journals Connector (OSTI)

A scattering chamber has been constructed which employs a number of radial slit units arranged at various angles with respect to the collimated beam of protons. A photographic plate is placed behind each slit unit and the tracks of protons which are scattered into the plate can be counted. To obtain cross sections from this apparatus the number of tracks per unit area must be determined. Protons were scattered from hydrogen gas at approximately 1.5-cm Hg pressure. Advantages of the design were relatively simple geometry, data obtained simultaneously at all angles, almost complete freedom from impurity-scattering, and short cyclotron running times. The differential cross sections were measured for 5.07-Mev protons from 14° to 150° in the center-of-mass system. The results indicate an S-wave phase shift of 54.5±0.6° and a repulsive P-wave phase shift of 0.05±0.09°. They are therefore quite consistent with pure S-wave scattering.

K. B. Mather

1951-04-15T23:59:59.000Z

358

Scattering theory without large-distance asymptotics  

E-Print Network [OSTI]

In conventional scattering theory, to obtain an explicit result, one imposes a precondition that the distance between target and observer is infinite. With the help of this precondition, one can asymptotically replace the Hankel function and the Bessel function with the sine functions so that one can achieve an explicit result. Nevertheless, after such a treatment, the information of the distance between target and observer is inevitably lost. In this paper, we show that such a precondition is not necessary: without losing any information of distance, one can still obtain an explicit result of a scattering rigorously. In other words, we give an rigorous explicit scattering result which contains the information of distance between target and observer. We show that at a finite distance, a modification factor --- the Bessel polynomial --- appears in the scattering amplitude, and, consequently, the cross section depends on the distance, the outgoing wave-front surface is no longer a sphere, and, besides the phase shift, there is an additional phase (the argument of the Bessel polynomial) appears in the scattering wave function.

Tong Liu; Wen-Du Li; Wu-Sheng Dai

2014-03-22T23:59:59.000Z

359

Gas-surface scattering with multiple collisions in the physisorption potential well Guoqing Fan and J. R. Manson  

E-Print Network [OSTI]

Gas-surface scattering with multiple collisions in the physisorption potential well Guoqing Fan The problem of gas-surface collisions is developed in terms of a theoretical formalism that allows calcula gas distributions are considered, a monoenergetic incident beam and an equilibrium gas appropriate

Manson, Joseph R.

360

Self-calibration of cluster dark energy studies: Observable-mass distribution  

Science Journals Connector (OSTI)

The exponential sensitivity of cluster number counts to the properties of the dark energy implies a comparable sensitivity to not only the mean but also the actual distribution of an observable-mass proxy given the true cluster mass. For example a 25% scatter in mass can provide a ?50% change in the number counts at z?2 for the upcoming SPT survey. Uncertainty in the scatter of this amount would degrade dark energy constraints to uninteresting levels. Given the shape of the actual mass function, the properties of the distribution may be internally monitored by the shape of the observable mass function. As a proof of principle, for a simple mass-independent Gaussian distribution the scatter may be self-calibrated to allow a measurement of the dark energy equation of state of ?(w)?0.1. External constraints on the mass variance of the distribution that are more accurate than ??ln?M2dark energy constraints.

Marcos Lima and Wayne Hu

2005-08-23T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Microstructural investigation, using polarized neutron scattering, of a martensitic steel for fusion reactors  

SciTech Connect (OSTI)

Small- and wide-angle polarized neutron scattering has been used to investigate the microstructure of modified martensitic steel DIN 1.4914 (MANET-type) developed as a potential candidate for the first wall of future fusion reactors. The nuclear-magnetic interference term and the comparison of the size distribution functions, obtained from the nuclear and from the magnetic scattering components, show that for quench temperatures lower than 1200 C three kinds of microstructural inhomogeneities can be identified: (a) tiny C-Cr elementary aggregates (1 nm or less in size), (b) larger (1--25 nm) Fe-carbides, (c) much larger inhomogeneities arising either from M{sub 23}C{sub 6} precipitates or from fluctuations in the Cr distribution. The scattering data are also compared with those previously obtained on the same samples from a conventional SANS instrument and the influence of the available Q-range on the accuracy of the obtained size distribution functions is discussed.

Coppola, R. [ENEA, Rome (Italy)] [ENEA, Rome (Italy); Kampmann, R.; Staron, P. [GKSS, Geesthacht (Germany)] [GKSS, Geesthacht (Germany); Magnani, M. [ENEA, Bologna (Italy)] [ENEA, Bologna (Italy)

1998-09-18T23:59:59.000Z

362

Repulsive nature of optical potentials for high-energy heavy-ion scattering  

E-Print Network [OSTI]

The recent works by the present authors predicted that the real part of heavy-ion optical potentials changes its character from attraction to repulsion around the incident energy per nucleon E/A = 200 - 300 MeV on the basis of the complex G-matrix interaction and the double-folding model (DFM) and revealed that the three-body force plays an important role there. In the present paper, we have precisely analyzed the energy dependence of the calculated DFM potentials and its relation to the elastic-scattering angular distributions in detail in the case of the $^{12}$C + $^{12}$C system in the energy range of E/A = 100 - 400 MeV. The tensor force contributes substantially to the energy dependence of the real part of the DFM potentials and plays an important role to lower the attractive-to-repulsive transition energy. The nearside and farside (N/F) decomposition of the elastic-scattering amplitudes clarifies the close relation between the attractive-to-repulsive transition of the potentials and the characteristic evolution of the calculated angular distributions with the increase of the incident energy. Based on the present analysis, we propose experimental measurements of the predicted strong diffraction phenomena of the elastic-scattering angular distribution caused by the N/F interference around the attractive-to-repulsive transition energy together with the reduced diffractions below and above the transition energy.

T. Furumoto; Y. Sakuragi; Y. Yamamoto

2010-10-08T23:59:59.000Z

363

Measurement of the Neutron Radius of 208Pb Through Parity-Violation in Electron Scattering  

E-Print Network [OSTI]

We report the first measurement of the parity-violating asymmetry A_PV in the elastic scattering of polarized electrons from 208Pb. A_PV is sensitive to the radius of the neutron distribution (Rn). The result A_PV = 0.656 \\pm 0.060 (stat) \\pm 0.014 (syst) ppm corresponds to a difference between the radii of the neutron and proton distributions Rn - Rp = 0.33 +0.16 -0.18 fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.

S. Abrahamyan; Z. Ahmed; H. Albataineh; K. Aniol; D. S. Armstrong; W. Armstrong; T. Averett; B. Babineau; A. Barbieri; V. Bellini; R. Beminiwattha; J. Benesch; F. Benmokhtar; T. Bielarski; W. Boeglin; A. Camsonne; M. Canan; P. Carter; G. D. Cates; C. Chen; J. -P. Chen; O. Hen; F. Cusanno; M. M. Dalton; R. De Leo; K. de Jager; W. Deconinck; P. Decowski; X. Deng; A. Deur; D. Dutta; A. Etile; D. Flay; G. B. Franklin; M. Friend; S. Frullani; E. Fuchey; F. Garibaldi; E. Gasser; R. Gilman; A. Giusa; A. Glamazdin; J. Gomez; J. Grames; C. Gu; O. Hansen; J. Hansknecht; D. W. Higinbotham; R. S. Holmes; T. Holmstrom; C. J. Horowitz; J. Hoskins; J. Huang; C. E. Hyde; F. Itard; C. -M. Jen; E. Jensen; G. Jin; S. Johnston; A. Kelleher; K. Kliakhandler; P. M. King; S. Kowalski; K. S. Kumar; J. Leacock; J. Leckey IV; J. H. Lee; J. J. LeRose; R. Lindgren; N. Liyanage; N. Lubinsky; J. Mammei; F. Mammoliti; D. J. Margaziotis; P. Markowitz; A. McCreary; D. McNulty; L. Mercado; Z. -E. Meziani; R. W. Michaels; M. Mihovilovic; N. Muangma; C. Muñoz-Camacho; S. Nanda; V. Nelyubin; N. Nuruzzaman; Y. Oh; A. Palmer; D. Parno; K. D. Paschke; S. K. Phillips; B. Poelker; R. Pomatsalyuk; M. Posik; A. J. R. Puckett; B. Quinn; A. Rakhman; P. E. Reimer; S. Riordan; P. Rogan; G. Ron; G. Russo; K. Saenboonruang; A. Saha; B. Sawatzky; A. Shahinyan; R. Silwal; S. Sirca; K. Slifer; P. Solvignon; P. A. Souder; M. L. Sperduto; R. Subedi; R. Suleiman; V. Sulkosky; C. M. Sutera; W. A. Tobias; W. Troth; G. M. Urciuoli; B. Waidyawansa; D. Wang; J. Wexler; R. Wilson; B. Wojtsekhowski; X. Yan; H. Yao; Y. Ye; Z. Ye; V. Yim; L. Zana; X. Zhan; J. Zhang; Y. Zhang; X. Zheng; P. Zhu

2012-01-13T23:59:59.000Z

364

HIGH BRILLIANCE X-RAY SCATTERING FOR  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

BRILLIANCE X-RAY SCATTERING FOR BRILLIANCE X-RAY SCATTERING FOR LIFE SCIENCES (LIX) Group Leader: Lin Yang Proposal Team: O. Bilsel 1 , B. Hsiao 2 , H. Huang 3 , T. Irving 4 , A. Menzel 5 , L. Pollack 6 , C. Riekel 7 , J. Rubert 8 , H. Tsuruta 9 , L. Yang 10 1 University of Massachusetts, 2 Stony Brook University, 3 Rice University, 4 IIT, 5SLS, 6 Cornell University, 7 European Synchrotron Radiation Facility, 8 NEU, 9 Stanford Synchrotron Radiation Lightsource, 10 Brookhaven National Laboratory TECHNIQUES AND CAPABILITIES APPLICATIONS ADDITIONAL INFORMATION * Energy range 2-20keV using undulator source. Simultaneous SAXS/WAXS to cover 0.003-3Å -1 at 12keV with 1 micron spot size * Time-resolved solution scattering with resolution of (1) microseconds to milliseconds using continuous-flow mixing (5µm x 10µm spot size) and (2) milliseconds using stopped-

365

Argonne CNM Highlight: Light Scattering by Nanoparticles  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Light Scattering by Nanoparticles: Understanding Confinement of Light for Nanophotonics Applications through Near-Field Scanning Optical Microscopy Light Scattering by Nanoparticles: Understanding Confinement of Light for Nanophotonics Applications through Near-Field Scanning Optical Microscopy Schematic of the apertureless near-field optical microscope Schematic of the apertureless near-field optical microscope. The optical scattering from the AFM probe tip provides the subdiffraction-limited optical field information. One of the motivations of nanoscience is to achieve sufficient control over photon propagation in nanostructures so as to effectively replace the electron with the photon in all-optical integrated circuits. The much greater speed and bandwidth of light pulses versus electrons promise new capabilities and size reduction of photon based “electronics.” Arrays of metal nanoparticles are currently considered a leading candidate for photon

366

Scattering Workshop May 16-17, 2006  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Workshop on Synchrotron X-ray Scattering Techniques in Materials and Workshop on Synchrotron X-ray Scattering Techniques in Materials and Environmental Sciences: Theory and Application. group shot on the steps of bldg 41 (Click image for a hi-res version) Date: May 16 (Lectures) May 17 (Hands-on practical session) Location: SSRL Overview: Modern synchrotron-based X-ray scattering (SR-XRS) techniques offer the ability to probe nano- and atomic-scale structures and order/disorder relationships that critically govern the properties of advanced technological and environmental materials. The high collimation, intensity, and tunability of SR allow the investigation of a wide range of materials, including thin films and interfaces, nanoparticles, amorphous materials, solutions, hydrated and disordered bacteriogenic minerals, and

367

Proton-Proton Scattering at 5 Mev  

Science Journals Connector (OSTI)

The differential cross section for the scattering of protons by protons has been measured at an energy of 4.96±0.08 Mev, at angles from 12.5° to 55° in the laboratory system. The scattering medium was hydrogen gas at a pressure of approximately 5 cm of Hg. The scattered or recoil protons were detected by nuclear track photographic plates. Approximately 10,000 proton tracks were counted at each angle of observation. An estimate indicates the error of each individual cross section to be about two percent. Because the observations at each angle are made simultaneously, the relative accuracy from one angle to another is smaller and amounts to about 1.3 percent.

R. E. Meagher

1950-06-15T23:59:59.000Z

368

Fast-Neutron Scattering from Germanium  

Science Journals Connector (OSTI)

Elastic and inelastic neutron scattering cross sections of natural germanium were measured in the incident neutron energy range 0.3-1.5 MeV with incident energy resolutions of ?20 keV. Neutron-velocity and ?-ray spectroscopic methods were employed to resolve the scattering to individual low-lying states. The results were interpreted in terms of the optical model and the statistical compound-nucleus model including effects due to fluctuations and correlations of resonance widths. Measured cross sections for inelastic scattering to a number of excited states in even Ge isotopes were reasonably well described by the statistical model of Hauser and Feshbach without corrections for width fluctuations and correlations.

D. Lister and A. B. Smith

1969-07-20T23:59:59.000Z

369

BUILDING A NETWORK FOR NEUTRON SCATTERING EDUCATION  

SciTech Connect (OSTI)

In a concerted effort supported by the National Science Foundation, the Department of Commerce, and the Department of Energy, the United States is rebuilding its leadership in neutron scattering capability through a significant investment in U.S. neutron scattering user facilities and related instrumentation. These unique facilities provide opportunities in neutron scattering to a broad community of researchers from academic institutions, federal laboratories, and industry. However, neutron scattering is often considered to be a tool for 'experts only' and in order for the U.S. research community to take full advantage of these new and powerful tools, a comprehensive education and outreach program must be developed. The workshop described below is the first step in developing a national program that takes full advantage of modern education methods and leverages the existing educational capacity at universities and national facilities. During March 27-28, 2008, a workshop entitled 'Building a Network for Neutron Scattering Education' was held in Washington, D.C. The goal of the workshop was to define and design a roadmap for a comprehensive neutron scattering education program in the United States. Successful implementation of the roadmap will maximize the national intellectual capital in neutron sciences and will increase the sophistication of research questions addressed by neutron scattering at the nation's forefront facilities. (See Appendix A for the list of attendees, Appendix B for the workshop agenda, Appendix C for a list of references. Appendix D contains the results of a survey given at the workshop; Appendix E contains summaries of the contributed talks.) The workshop brought together U.S. academicians, representatives from neutron sources, scientists who have developed nontraditional educational programs, educational specialists, and managers from government agencies to create a national structure for providing ongoing neutron scattering education. A concerted effort was made to involve representatives from historically black colleges and universities (HBCUs) and minority educational institutions (MEIs). The roadmap contained herein provides the path to a national infrastructure for education of students, faculty, and professional researchers who wish to make use of national neutron scattering facilities but do not have (or do not believe they have) the educational background to do so. Education of other stakeholders, including the public, students in kindergarten through twelfth grade (K-12), and policy makers is also included. The opening sessions of the workshop provided the current status of neutron scattering education in North America, Europe, and Australia. National neutron sources have individually developed outreach and advertising programs aimed at increasing awareness among researchers of the potential applications of neutron scattering. However, because their principal mission is to carry out scientific research, their outreach efforts are necessarily self-limiting. The opening session was designed to build awareness that the individual programs need to be coupled with, and integrated into, a broader education program that addresses the complete range of experience, from the student to the experienced researcher, and the wide range of scientific disciplines covered by neutron scattering. Such a program must also take full advantage of existing educational programs and expertise at universities and expand them using modern distance learning capabilities, recognizing that the landscape of education is changing.

Pynn, Roger [ORNL; Baker, Shenda Mary [ORNL; Louca, Despo A [ORNL; McGreevy, Robert L [ORNL; Ekkebus, Allen E [ORNL; Kszos, Lynn A [ORNL; Anderson, Ian S [ORNL

2008-10-01T23:59:59.000Z

370

Slow-Neutron Scattering by Rotators. II  

Science Journals Connector (OSTI)

The methods developed in a previous paper for extending the neutron scattering formalism of Zemach and Glauber to any type of molecular rotator have been employed to derive generalized forms of the differential cross sections for rotator scattering. A mass-ratio expansion for the treatment of the high-energy limit is illustrated on the classical cross section and then employed in the treatment of the more general quantum-mechanical expression for the differential cross section. The results apply to an arbitrarily asymmetric rotator. The very low energy approximation is carried out for the symmetric rotator, and the procedure is compared with the explicit summing of the partial cross sections for individual rotational transitions. The inelastic correction to the static approximation for interference scattering is calculated to an accuracy of first order in the mass ratios for the case of the symmetric rotator.

Howard C. Volkin

1960-02-15T23:59:59.000Z

371

Off-resonance atomic Bragg scattering  

SciTech Connect (OSTI)

We performed extensive measurements on the scattering efficiency of atomic Bragg scattering on a standing light wave up to sixth order and developed a two-state Demkov model to explain the results. Using an effective 2N-photon coupling between the original and the reflected momentum states and the assumption of a mostly adiabatic transfer we derived the scattering probability. This probability has two factors: an oscillating part which represents the well-known Pendelloesung oscillation and a part that is peaked in the energy difference between the two momentum states. This last part describes the tolerance on the Bragg condition for angular misalignment. Comparison of the measurements and numerical simulations with this model shows good agreement.

Jansen, M. A. H. M.; Domen, K. F. E. M.; Beijerinck, H. C. W.; Leeuwen, K. A. H. van [Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands)

2007-11-15T23:59:59.000Z

372

Scattering and; Delay, Scale, and Sum Migration  

SciTech Connect (OSTI)

How do we see? What is the mechanism? Consider standing in an open field on a clear sunny day. In the field are a yellow dog and a blue ball. From a wave-based remote sensing point of view the sun is a source of radiation. It is a broadband electromagnetic source which, for the purposes of this introduction, only the visible spectrum is considered (approximately 390 to 750 nanometers or 400 to 769 TeraHertz). The source emits an incident field into the known background environment which, for this example, is free space. The incident field propagates until it strikes an object or target, either the yellow dog or the blue ball. The interaction of the incident field with an object results in a scattered field. The scattered field arises from a mis-match between the background refractive index, considered to be unity, and the scattering object refractive index ('yellow' for the case of the dog, and 'blue' for the ball). This is also known as an impedance mis-match. The scattering objects are referred to as secondary sources of radiation, that radiation being the scattered field which propagates until it is measured by the two receivers known as 'eyes'. The eyes focus the measured scattered field to form images which are processed by the 'wetware' of the brain for detection, identification, and localization. When time series representations of the measured scattered field are available, the image forming focusing process can be mathematically modeled by delayed, scaled, and summed migration. This concept of optical propagation, scattering, and focusing have one-to-one equivalents in the acoustic realm. This document is intended to present the basic concepts of scalar scattering and migration used in wide band wave-based remote sensing and imaging. The terms beamforming and (delayed, scaled, and summed) migration are used interchangeably but are to be distinguished from the narrow band (frequency domain) beamforming to determine the direction of arrival of a signal, and seismic migration in which wide band time series are shifted but not to form images per se. Section 3 presents a mostly graphically-based motivation and summary of delay, scale, and sum beamforming. The model for incident field propagation in free space is derived in Section 4 under specific assumptions. General object scattering is derived in Section 5 and simplified under the Born approximation in Section 6. The model of this section serves as the basis in the derivation of time-domain migration. The Foldy-Lax, full point scatterer scattering, method is derived in Section 7. With the previous forward models in hand, delay, scale, and sum beamforming is derived in Section 8. Finally, proof-of-principle experiments are present in Section 9.

Lehman, S K

2011-07-06T23:59:59.000Z

373

Annual Coal Distribution Report  

Gasoline and Diesel Fuel Update (EIA)

Distribution Report Release Date: December 19, 2013 | Next Release Date: December 12, 2014 | full report | RevisionCorrection Revision to the Annual Coal Distribution Report...

374

Distribution Grid Integration  

Broader source: Energy.gov [DOE]

The DOE Systems Integration team funds distribution grid integration research and development (R&D) activities to address the technical issues that surround distribution grid planning,...

375

Neutron Scattering Application of Polarized Solid Target in Materials Research  

SciTech Connect (OSTI)

Neutron scattering is one of the most important tools for materials research. However, neutrons are very expensive to produce. Even with the best sources, such as the newly completed Spallation Neutron Source at the Oak Ridge National Laboratory, most neutron scattering experiments are still flux limited. One way to improve the experimental data is polarized neutron scattering from polarized solid target: the strong spin-dependent neutron scattering cross-section can increase the coherent scattering and decrease the incoherent scattering at the same time, thereby significantly enhancing the signal to noise ratio. Hydrogen, abundant in most soft condensed matters, has a strong spin-dependent scattering cross-section. Early applications of polarized neutron scattering in biological soft condensed matters have already demonstrated the huge potential of this technique. Here we describe the polarized target program at the SNS. The program is under active construction and is aimed at serving neutron scattering at the SNS.

Zhao, Jinkui [ORNL

2008-09-01T23:59:59.000Z

376

Off-specular scattering in neutron reflectometry  

SciTech Connect (OSTI)

When neutrons are scattered at small angles from planar, laterally homogeneous, stratified media, only specular (mirror like) reflection is observed. Sample inhomogeneities, such as interfacial roughness or voids, give rise to off-specular scattering which has been observed in many experiments with neutrons and x-rays. The easiest way to describe this scattering theoretically is based on the distorted-wave Born approximation (DWBA), which uses the neutron wavefunctions that describe reflection from a smooth surface as the basis functions for perturbation theory. From the DWBA one may obtain a number of qualitative results which are supported by experiment. Examples include the Yoneda fringes observed in reflection experiments with microscopically rough surfaces and the constant-q{sub z} fringes observed for multilayers with correlated, rough interfaces. One must, however, use the DWBA with care. When the correlation range within the reflecting interfaces is large--for example, when a surface is composed of misoriented facets--the approximation breaks down. Some authors have also reported a lack of quantitative agreement between versions of the DWBA calculations and the scattering observed with microscopically rough surfaces. A remarkable feature of neutron (or x-ray) reflectometry is the length scales that are probed within reflecting surfaces. These range from a few hundred Angstroms up to several microns, allowing neutron scattering to probe objects of a size normally visible by optical microscopy! The intent of this paper is to provide a simple description of scattering from rough surfaces that is accessible to a wide audience. Mathematical completeness is sacrificed in favor of intuitive arguments and experimental examples.

Pynn, R.; Baker, S.M.; Smith, G.; Fitzsimmons, M. [Los Alamos National Lab., NM (United States). Manuel Lujan Jr. Neutron Scattering Center

1995-03-01T23:59:59.000Z

377

Theory of coherent neutron scattering by hydrogen-bonded ferroelectrics at low temperatures. I. General expression for inelastic coherent scattering of slow neutrons and effective thermal factors  

Science Journals Connector (OSTI)

The differential cross section for inelastic coherent scattering of slow neutrons scattered by hydrogen-bonded ferroelectrics at low temperatures...

S. Stamenkovi?

1972-12-01T23:59:59.000Z

378

Scattering theory with localized non-Hermiticities  

SciTech Connect (OSTI)

In the context of the recent interest in solvable models of scattering mediated by non-Hermitian Hamiltonians (cf. H. F. Jones, Phys. Rev. D 76, 125003 (2007)) we show that the well-known variability of the ad hoc choice of the metric {theta} which defines the physical Hilbert space of states can help us to clarify several apparent paradoxes. We argue that with a suitable {theta}, a fully plausible physical picture of the scattering can be recovered. Quantitatively, our new recipe is illustrated on an exactly solvable toy model.

Znojil, Miloslav [Nuclear Physics Institute ASCR, 250 68 Rez (Czech Republic)

2008-07-15T23:59:59.000Z

379

Quantum-entanglement-initiated super Raman scattering  

SciTech Connect (OSTI)

It has now been possible to prepare a chain of ions in an entangled state and thus the question arises: How will the optical properties of a chain of entangled ions differ from say a chain of independent particles? We investigate nonlinear optical processes in such chains. Since light scattering is quite a versatile technique to probe matter, we explicitly demonstrate the possibility of entanglement-produced super Raman scattering. Our results suggest the possibility of similar enhancement factors in other nonlinear processes like four-wave mixing.

Agarwal, G. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2011-02-15T23:59:59.000Z

380

[Inelastic electron scattering from surfaces]. [Progress report  

SciTech Connect (OSTI)

This program uses ab-initio and multiple scattering to study surface dynamical processes; high-resolution electron-energy loss spectroscopy is used in particular. Off-specular excitation cross sections are much larger if electron energies are in the LEED range (50--300 eV). The analyses have been extended to surfaces of ordered alloys. Phonon eigenvectors and eigenfrequencies were used as inputs to electron-energy-loss multiple scattering cross section calculations. Work on low-energy electron and positron holography is mentioned.

Not Available

1993-10-01T23:59:59.000Z

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381

Neutron Scattering in Ortho- and Parahydrogen  

Science Journals Connector (OSTI)

The cross section for the scattering of cold neutrons by parahydrogen is sensitive to the range of the forces in the triplet state. To facilitate the determination of the range from such measurements, expressions have been obtained for the dependence of the ortho and para cross sections on neutron energy and hydrogen temperature. The interpretation of transmission measurements is complicated by the existence of radiative capture, which is comparable in importance to scattering in parahydrogen. The different energy dependence of the two processes should permit an accurate determination of the individual cross sections.

Morton Hamermesh and Julian Schwinger

1947-05-15T23:59:59.000Z

382

Neutron scattering measurements at intermediate energies  

E-Print Network [OSTI]

The study of elastic neutron scattering at intermediate energies is essential for the understanding of the isovector term in the nucleon-nucleus interaction, as well as for the development of macroscopic and microscopic optical potentials at these energies. The techniques used for neutron scattering measurements is presented in this paper, as well as the di culties encountered. The few facilities that have been used are reviewed, and a newly installed setup for such measurements in Uppsala is described. Finally, the normalization problem is speci cally addressed. 1

N. Olsson; J. Blomgren; E. Ramstrom

383

Electromagnetic wave scattering by small bodies  

E-Print Network [OSTI]

A reduction of the Maxwell's system to a Fredholm second-kind integral equation with weakly singular kernel is given for electromagnetic (EM) wave scattering by one and many small bodies. This equation is solved asymptotically as the characteristic size of the bodies tends to zero. The technique developed is used for solving the many-body EM wave scattering problem by rigorously reducing it to solving linear algebraic systems, completely bypassing the usage of integral equations. An equation is derived for the effective field in the medium, in which many small particles are embedded. A method for creating a desired refraction coefficient is outlined.

A. G. Ramm

2008-04-21T23:59:59.000Z

384

Measurement of the Azimuthal Correlation between the most Forward Jet and the Scattered Positron in Deep-Inelastic Scattering at HERA  

E-Print Network [OSTI]

Deep-inelastic positron-proton scattering events at low photon virtuality Q^2 with a forward jet, produced at small angles with respect to the proton beam, are measured with the H1 detector at HERA. A subsample of events with an additional jet in the central region is also studied. For both samples differential cross sections and normalised distributions are measured as a function of the azimuthal angle difference, Delta phi, between the forward jet and the scattered positron. The sensitivity to QCD evolution mechanisms is tested by comparing the data to predictions of Monte Carlo generators based on different evolution approaches as well as to next-to-leading order calculations.

Aaron, F D; Andreev, V; Backovic, S; Baghdasaryan, A; Baghdasaryan, S; Barrelet, E; Bartel, W; Begzsuren, K; Belousov, A; Belov, P; Bizot, J C; Boudry, V; Bozovic-Jelisavcic, I; Bracinik, J; Brandt, G; Brinkmann, M; Brisson, V; Britzger, D; Bruncko, D; Bunyatyan, A; Bystritskaya, L; Campbell, A J; Cantun Avila, K B; Ceccopieri, F; Cerny, K; Cerny, V; Chekelian, V; Contreras, J G; Coughlan, J A; Cvach, J; Dainton, J B; Daum, K; Delcourt, B; Delvax, J; De Wolf, E A; Diaconu, C; Dobre, M; Dodonov, V; Dossanov, A; Dubak, A; Eckerlin, G; Egli, S; Eliseev, A; Elsen, E; Favart, L; Fedotov, A; Felst, R; Feltesse, J; Ferencei, J; Fischer, D J; Fleischer, M; Fomenko, A; Gabathuler, E; Gayler, J; Ghazaryan, S; Glazov, A; Goerlich, L; Gogitidze, N; Gouzevitch, M; Grab, C; Grebenyuk, A; Greenshaw, T; Grell, B R; Grindhammer, G; Habib, S; Haidt, D; Helebrant, C; Henderson, R C W; Hennekemper, E; Henschel, H; Herbst, M; Herrera, G; Hildebrandt, M; Hiller, K H; Hoffmann, D; Horisberger, R; Hreus, T; Huber, F; Jacquet, M; Janssen, X; Jonsson, L; Jung, H; Kapichine, M; Kenyon, I R; Kiesling, C; Klein, M; Kleinwort, C; Kluge, T; Kogler, R; Kostka, P; Kraemer, M; Kretzschmar, J; Kruger, K; Landon, M P J; Lange, W; Lastovicka-Medin, G; Laycock, P; Lebedev, A; Lendermann, V; Levonian, S; Lipka, K; List, B; List, J; Lopez-Fernandez, R; Lubimov, V; Makankine, A; Malinovski, E; Marage, P; Martyn, H U; Maxfield, S J; Mehta, A; Meyer, A B; Meyer, H; Meyer, J; Mikocki, S; Milcewicz-Mika, I; Moreau, F; Morozov, A; Morris, J V; Mudrinic, M; Muller, K; Naumann, Th; Newman, P R; Niebuhr, C; Nikitin, D; Nowak, G; Nowak, K; Olsson, J E; Ozerov, D; Pahl, P; Palichik, V; Panagoulias, I; Pandurovic, M; Papadopoulou, Th; Pascaud, C; Patel, G D; Perez, E; Petrukhin, A; Picuric, I; Piec, S; Pirumov, H; Pitzl, D; Placakyte, R; Pokorny, B; Polifka, R; Povh, B; Radescu, V; Raicevic, N; Ravdandorj, T; Reimer, P; Rizvi, E; Robmann, P; Roosen, R; Rostovtsev, A; Rotaru, M; Ruiz Tabasco, J E; Rusakov, S; Salek, D; Sankey, D P C; Sauter, M; Sauvan, E; Schmitt, S; Schoeffel, L; Schoning, A; Schultz-Coulon, H C; Sefkow, F; Shtarkov, L N; Shushkevich, S; Sloan, T; Smiljanic, I; Soloviev, Y; Sopicki, P; South, D; Spaskov, V; Specka, A; Staykova, Z; Steder, M; Stella, B; Stoicea, G; Straumann, U; Sykora, T; Thompson, P D; Tran, T H; Traynor, D; Truol, P; Tsakov, I; Tseepeldorj, B; Turnau, J; Valkarova, A; Vallee, C; Van Mechelen, P; Vazdik, Y; Wegener, D; Wunsch, E; Zacek, J; Zalesak, J; Zhang, Z; Zhokin, A; Zohrabyan, H; Zomer, F

2012-01-01T23:59:59.000Z

385

Bimodal Island Size Distribution in Heteroepitaxial Growth  

Science Journals Connector (OSTI)

A bimodal size distribution of two-dimensional islands is inferred during interface formation in heteroepitaxial growth of bismuth ferrite on (001) oriented SrTiO3 by sputter deposition. Features observed by in situ x-ray scattering are explained by a model where coalescence of islands determines the growth kinetics with negligible surface diffusion on SrTiO3. Small clusters maintain a compact shape as they coalesce, while clusters beyond a critical size impinge to form large irregular connected islands and a population of smaller clusters forms in the spaces between the larger ones.

P.?V. Chinta and R.?L. Headrick

2014-02-20T23:59:59.000Z

386

Simultaneous QCD analysis of diffractive and inclusive deep-inelastic scattering data  

SciTech Connect (OSTI)

We perform a next-to-leading order (NLO) QCD analysis of deep-inelastic scattering data, in which we account for absorptive corrections. These corrections are determined from a simultaneous analysis of diffractive deep-inelastic data. The absorptive effects are found to enhance the size of the gluon distribution at small x, such that a negative input gluon distribution at Q{sup 2}=1 GeV{sup 2} is no longer required. We discuss the problem that the gluon distribution is valence-like at low scales, whereas the sea quark distribution grows with decreasing x. Our study hints at the possible importance of power corrections for Q{sup 2}{approx_equal}1-2 GeV{sup 2}.

Martin, A.D.; Watt, G. [Institute for Particle Physics Phenomenology, University of Durham, DH1 3LE (United Kingdom); Ryskin, M.G. [Institute for Particle Physics Phenomenology, University of Durham, DH1 3LE (United Kingdom); Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg, 188300 (Russian Federation)

2004-11-01T23:59:59.000Z

387

Compton Scattering Sources and Applications at LLNL  

SciTech Connect (OSTI)

We report the design and current status of a monoenergetic laser-based Compton scattering 0.5-2.5 MeV {gamma}-ray source. Previous nuclear resonance fluorescence results and future linac and laser developments for the source are presented.

Albert, Felicie; Anderson, S. G.; Anderson, G.; Bayramian, A.; Betts, S. M.; Cross, R. R.; Ebbers, C. A.; Gibson, D. J.; Marsh, R. A.; Messerly, M.; Shverdin, M. Y.; Wu, S. S.; Hartemann, F. V.; Scarpetti, R.; Siders, C. W.; Barty, C. P. J. [Lawrence Livermore National Laboratory, NIF and Photon Science, 7000 East Avenue, Livermore, CA, 94550 (United States)

2010-11-04T23:59:59.000Z

388

Rutherford Scattering MIT Department of Physics  

E-Print Network [OSTI]

Rutherford Scattering MIT Department of Physics (Dated: September 1, 2013) This is an experiment on the web site. SUGGESTED PROGRESS CHECK FOR END OF 2nd SESSION Plot the rate of alpha particle observations, an alpha particle traversing a thin gold film should experience many small angle deflections as it passes

Seager, Sara

389

The Phase of the Scattering Matrix  

E-Print Network [OSTI]

Vacuum polarization in external fields is treated by way of calculating - exactly and then perturbatively - the phase of the quantum scattering matrix in the Shale-Stinespring approach to field theory. The link between the Shale-Stinespring method and the Epstein-Glaser renormalization procedure is highlighted.

Gracía-Bondía, José M

2000-01-01T23:59:59.000Z

390

Fiber optic probe for light scattering measurements  

DOE Patents [OSTI]

This invention is comprised of a fiber optic probe and a method for using the probe for light scattering analyses of a sample. The probe includes a probe body with an inlet for admitting a sample into an interior sample chamber, a first optical fiber for transmitting light from a source into the chamber, and a second optical fiber for transmitting light to a detector such as a spectrophotometer. The interior surface of the probe carries a coating that substantially prevents non-scattered light from reaching the second fiber. The probe is placed in a region where the presence and concentration of an analyte of interest are to be detected, and a sample is admitted into the chamber. Exciting light is transmitted into the sample chamber by the first fiber, where the light interacts with the sample to produce Raman-scattered light. At least some of the Raman- scattered light is received by the second fiber and transmitted to the detector for analysis. Two Raman spectra are measured, at different pressures. The first spectrum is subtracted from the second to remove background effects, and the resulting sample Raman spectrum is compared to a set of stored library spectra to determine the presence and concentration of the analyte.

Nave, S.E.; Livingston, R.R.; Prather, W.S.

1993-01-01T23:59:59.000Z

391

Rapid Research Note Raman Scattering in Resonance  

E-Print Network [OSTI]

-uniformity in the ternary alloy InGaN [4, 5]. However, resonance Raman scattering at bound excitons as reported for CdS doped 220 mm thick GaN film grown by hydride vapor phase epitaxy. Sapphire (0001) with a sputtered Zn

Nabben, Reinhard

392

Multiparameter light scattering for rapid virus identification  

SciTech Connect (OSTI)

An instrument for making multiparameter light scattering (MLS) measurements from viral suspensions has been described. Calibration methods and a technique for the correction of artifacts were also presented. This measurement technique may have broad applications in cell biology in general and in virology in particular. It may be possible to use MLS to identify viruses directly from clinical specimens. 8 references, 7 figures.

Salzman, G.C.; Grace, W.K.; McGregor, D.M.; Gregg, C.T.

1984-01-01T23:59:59.000Z

393

Focusing on moving targets through scattering samples  

E-Print Network [OSTI]

. http://dx.doi.org/10.1364/OPTICA.1.000227 1. INTRODUCTION Focusing light through highly scattering-2536/14/040227-06$15/0$15.00 © 2014 Optical Society of America Research Article Vol. 1, No. 4 / October 2014 / Optica 227 #12

Yang, Changhuei

394

Slow-Neutron Scattering by Molecules  

Science Journals Connector (OSTI)

The operator formalism in slow-neutron scattering theory introduced by Wick and by Zemach and Glauber is considered in an approximation in which molecular rotational and vibrational effects are explicitly separated. The combined effects of rotation and translation are treated in terms of the Sachs-Teller "mass-tensor" concept, which is rederived on the basis of a rigid molecule Hamiltonian and extended to include interference effects. Only elastic vibrational transitions from the ground vibrational state are considered. The applicable neutron energy range is restricted to values large compared to the rotational level separation but below the vibrational threshold.The method is applicable to the calculation of differential as well as total scattering cross sections and to molecules of arbitrary structure. Expressions in closed form for these cross sections are obtained through use of an approximate procedure for averaging over molecular orientations. In the case of hydrogenous molecules, where direct scattering is dominant, the scattering by a given nucleus is described in terms of two parameters, viz., an effective nuclear mass for rotation and translation, and a vibrational constant. The relative simplicity of the method is illustrated in the calculation of the differential and total cross sections of CH4 and the total cross section of H2. Agreement of these calculations with experiment and with other calculations is good.

T. J. Krieger and M. S. Nelkin

1957-04-15T23:59:59.000Z

395

SCATTERING BEHAVIOR OF TRANSITIONAL SHOCK WAVES  

E-Print Network [OSTI]

SCATTERING BEHAVIOR OF TRANSITIONAL SHOCK WAVES Kevin R. Zumbrun Bradley J. Plohr Dan Marchesin September, 1991 Abstract. We study the stability and asymptotic behavior of transitional shock waves as solutions of a parabolic system of conservation laws. In contrast to classical shock waves, transitional

New York at Stoney Brook, State University of

396

Fiber optic probe for light scattering measurements  

DOE Patents [OSTI]

A fiber optic probe and a method for using the probe for light scattering analyses of a sample. The probe includes a probe body with an inlet for admitting a sample into an interior sample chamber, a first optical fiber for transmitting light from a source into the chamber, and a second optical fiber for transmitting light to a detector such as a spectrophotometer. The interior surface of the probe carries a coating that substantially prevents non-scattered light from reaching the second fiber. The probe is placed in a region where the presence and concentration of an analyte of interest are to be detected, and a sample is admitted into the chamber. Exciting light is transmitted into the sample chamber by the first fiber, where the light interacts with the sample to produce Raman-scattered light. At least some of the Raman-scattered light is received by the second fiber and transmitted to the detector for analysis. Two Raman spectra are measured, at different pressures. The first spectrum is subtracted from the second to remove background effects, and the resulting sample Raman spectrum is compared to a set of stored library spectra to determine the presence and concentration of the analyte.

Nave, Stanley E. (Evans, GA); Livingston, Ronald R. (Aiken, SC); Prather, William S. (Augusta, GA)

1995-01-01T23:59:59.000Z

397

Microscopic prescriptions for elastic and inelastic scattering  

SciTech Connect (OSTI)

New prescriptions are presented for the single scattering approximations for the optical potential and distorted-wave impulse approximation transition amplitudes. They are based on the application of systematics observed in the behavior of off-shell T matrices calculated from realistic potential models.

Redish, E.F.; Stricker-Bauer, K.

1987-04-01T23:59:59.000Z

398

Doppler Effect in Light-Scattering  

Science Journals Connector (OSTI)

... the subject classically, the result to be expected is obvious: there should be a Doppler broadening of the incident spectral line, varying with the angle of observation, and determined ... should persist in the scattered light in the same position with no change except a Doppler broadening.

C. V. RAMAN

1931-10-10T23:59:59.000Z

399

E-Print Network 3.0 - angle scattering studies Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Search Sample search results for: angle scattering studies Page: << < 1 2 3 4 5 > >> 1 Neutron Scattering in Polymer Micelle Characterization Summary: scattering Small Angle...

400

E-Print Network 3.0 - alamos neutron scattering Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

neutron scattering Search Powered by Explorit Topic List Advanced Search Sample search results for: alamos neutron scattering Page: << < 1 2 3 4 5 > >> 1 Neutron Scattering Society...

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Absorption and scattering by long and randomly oriented linear chains of spheres  

E-Print Network [OSTI]

experimental measurements absorption and scattering cross-C. Bohren and D. Huffman, Absorption and Scattering of LightScattering and absorption of light by nonspherical

Lee, Euntaek; Pilon, Laurent

2013-01-01T23:59:59.000Z

402

Energy Distribution at Large Angles of High-Energy Electrons in Bremsstrahlung  

Science Journals Connector (OSTI)

The energy distribution of high-energy electrons, that have been scattered by the nuclear potential and have lost energy by bremsstrahlung, has been investigated. It has been found that there is a peak in the energy distribution which occurs at energies of the order of mc2. The nature of and reasons for the peak are discussed. Formulas for the energy distribution near the peak and for the area under the peak are given. Similar results apply also to pair production.

David G. Keiffer and George Parzen

1956-02-15T23:59:59.000Z

403

Universality of electron distributions in high-energy air showers - description of Cherenkov light production  

E-Print Network [OSTI]

The shower simulation code CORSIKA has been used to investigate the electron energy and angular distributions in high-energy showers. Based on the universality of both distributions, we develop an analytical description of Cherenkov light emission in extensive air showers, which provides the total number and angular distribution of photons. The parameterisation can be used e.g. to calculate the contribution of direct and scattered Cherenkov light to shower profiles measured with the air fluorescence technique.

F. Nerling; J. Blümer; R. Engel; M. Risse

2005-12-22T23:59:59.000Z

404

Probing Pulsar Winds Using Inverse Compton Scattering  

E-Print Network [OSTI]

We investigate the effects of inverse Compton scattering by electrons and positrons in the unshocked winds of rotationally-powered binary pulsars. This process can scatter low energy target photons to produce gamma rays with energies from MeV to TeV. The binary radio pulsars PSR B1259-63 and PSR J0045-73 are both in close eccentric orbits around bright main sequence stars which provide a huge density of low energy target photons. The inverse Compton scattering process transfers momentum from the pulsar wind to the scattered photons, and therefore provides a drag which tends to decelerate the pulsar wind. We present detailed calculations of the dynamics of a pulsar wind which is undergoing inverse Compton scattering, showing that the deceleration of the wind of PSR B1259-63 due to `inverse Compton drag' is small, but that this process may confine the wind of PSR J0045-73 before it attains pressure balance with the outflow of its companion star. We calculate the spectra and light curves of the resulting inverse Compton emission from PSR B1259-63 and show that if the size of the pulsar wind nebula is comparable to the binary separation, then the gamma-ray emission from the unshocked wind may be detectable by atmospheric Cerenkov detectors or by the new generation of satellite-borne gamma-ray detectors such as INTEGRAL and GLAST. This mechanism may therefore provide a direct probe of the freely-expanding regions of pulsar winds, previously thought to be invisible.

Lewis Ball; J. G. Kirk

1999-08-18T23:59:59.000Z

405

SunShot Initiative: Scattering Solar Thermal Concentrators  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Scattering Solar Thermal Scattering Solar Thermal Concentrators to someone by E-mail Share SunShot Initiative: Scattering Solar Thermal Concentrators on Facebook Tweet about SunShot Initiative: Scattering Solar Thermal Concentrators on Twitter Bookmark SunShot Initiative: Scattering Solar Thermal Concentrators on Google Bookmark SunShot Initiative: Scattering Solar Thermal Concentrators on Delicious Rank SunShot Initiative: Scattering Solar Thermal Concentrators on Digg Find More places to share SunShot Initiative: Scattering Solar Thermal Concentrators on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards CSP Research & Development Thermal Storage CSP Recovery Act Baseload CSP SunShot Multidisciplinary University Research Initiative CSP Heat Integration for Baseload Renewable Energy Deployment

406

Phonon Transport and Thermodynamics Probed with Neutron Scattering...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Phonon Transport and Thermodynamics Probed with Neutron Scattering Oct 22 2014 10:00 AM - 11:00 AM Olivier Delaire, Scattering and Thermophysics Group, MSTD, ORNL, Oak Ridge...

407

Inverse scattering by a continuation method with initial guesses from ...  

E-Print Network [OSTI]

Sep 5, 2007 ... b Department of Mathematics and Statistics, Louisiana Tech University, ... The present paper focuses on the inverse scattering problem. ..... Example 1: (a) the true scatterer; (b) the initial guess; and (c) the final reconstruction.

2007-10-11T23:59:59.000Z

408

Rotational motion in plastic quinuclidine : Results from quasielastic neutron scattering  

E-Print Network [OSTI]

563 Rotational motion in plastic quinuclidine : Results from quasielastic neutron scattering C. 2014 Results of incoherent quasielastic neutron scattering experiments on quinuclidine, C7Hl3N, in its

Boyer, Edmond

409

Scattered neutron tomography based on a neutron transport problem  

E-Print Network [OSTI]

scattering objects because it does not adequately account for the scattering component of the neutron beam intensity exiting the sample. We proposed a new method of computed tomography which employs an inverse problem analysis of both the transmitted...

Scipolo, Vittorio

2005-11-01T23:59:59.000Z

410

Aspherical refractive lenses for small-angle neutron scattering  

Science Journals Connector (OSTI)

This paper discusses the testing and simulation of aspherical neutron lenses as focusing elements for small-angle neutron scattering and their transparency with respect to thermal diffuse scattering.

Frielinghaus, H.

2009-06-20T23:59:59.000Z

411

Anisotropic light scattering of individual sickle red blood cells  

E-Print Network [OSTI]

We present the anisotropic light scattering of individual red blood cells (RBCs) from a patient with sickle cell disease (SCD). To measure light scattering spectra along two independent axes of elongated-shaped sickle RBCs ...

Kim, Youngchan

412

Bright-White Beetle Scales Optimise Multiple Scattering of Light  

E-Print Network [OSTI]

Whiteness arises from diffuse and broadband reflection of light typically achieved through optical scattering in randomly structured media. In contrast to structural colour due to coherent scattering, white appearance ...

Burresi, Matteo

413

A study of neutron-deuteron scattering in configuration space  

E-Print Network [OSTI]

A new computational method for solving the configuration-space Faddeev equations for the breakup scattering problem has been applied to nd scattering both below and above the two-body threshold.

V. M. Suslov; M. A. Braun; I. Filikhin; B. Vlahovic

2006-10-09T23:59:59.000Z

414

11th LANSCE School on Neutron Scattering | Lecturers  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

they lead to new knowledge of existing materials or novel materials concepts. Examples of Neutron scattering, X-ray scattering and neutron or X-ray tomography will be shown which...

415

Elastic scattering of Dirac fermions on Schwarzschild black holes  

E-Print Network [OSTI]

Approximative analytic solutions of the Dirac equation in the Schwarzschild geometry are used for building the partial wave analysis of the Dirac fermions scattered by black holes. The analytic expressions of the differential cross section and induced polarization degree are derived in terms of scattering angle, mass of the black-hole, energy and mass of the fermion. We perform a graphical study of differential cross section analysing the forward/backward scattering (known also as glory scattering) and the polarization degree as functions of scattering angle. The graphical analysis shows the presence of oscillations in scattering intensity around forward/backward directions, phenomena known as spiral scattering. In addition, we find that the scattering probability increases significantly for fermions with large angular momentum. The energy dependence of the differential cross section is also established by using analytical and graphical methods.

Ion I. Cotaescu; Cosmin Crucean; Ciprian A. Sporea

2014-10-08T23:59:59.000Z

416

Incoherent x-ray scattering in single molecule imaging  

E-Print Network [OSTI]

Imaging of the structure of single proteins or other biomolecules with atomic resolution would be enormously beneficial to structural biology. X-ray free-electron lasers generate highly intense and ultrashort x-ray pulses, providing a route towards imaging of single molecules with atomic resolution. The information on molecular structure is encoded in the coherent x-ray scattering signal. In contrast to crystallography there are no Bragg reflections in single molecule imaging, which means the coherent scattering is not enhanced. Consequently, a background signal from incoherent scattering deteriorates the quality of the coherent scattering signal. This background signal cannot be easily eliminated because the spectrum of incoherently scattered photons cannot be resolved by usual scattering detectors. We present an ab initio study of incoherent x-ray scattering from individual carbon atoms, including the electronic radiation damage caused by a highly intense x-ray pulse. We find that the coherent scattering pa...

Slowik, Jan Malte; Dixit, Gopal; Jurek, Zoltan; Santra, Robin

2014-01-01T23:59:59.000Z

417

A comparison of bistatic scattering from two geologically distinct abyssal hills  

Science Journals Connector (OSTI)

The bistatic scattering characteristics of two geologically distinct abyssal hills located on the western flank of the Mid-Atlantic Ridge known as B ? and C ? are experimentally compared using data acquired with low-frequency towed-array systems at 1 2 convergence zone (?33 km) stand-off. The comparison is significant because the abyssal hills span the two classes of elevated seafloor crust that cover the Mid-Atlantic Ridge. The highly lineated B ? feature is representative of abyssal hills composed of outside corner crust the most commonly occurring category whereas the domed C ? promontory is representative of the rougher low-aspect-ratio abyssal hills composed of inside corner crust. The latter are less common and usually restricted to segment valley margins. The mean biazimuthal scattering distributions of the two abyssal hills each exhibit Lambertian behavior with comparable albedos suggesting that the distinction between abyssal hills composed of differing crust is not significant in modeling long-range reverberation. The adverse effect of using bathymetry that undersamples seafloor projected area in scattering strength analysis is also quantified with data from the B ? ridge. Specifically the use of undersampled bathymetry can lead to significant overestimates in the strength of seafloor scattering.

Nicholas C. Makris

2000-01-01T23:59:59.000Z

418

Quark Structure of the Nucleon and Angular Asymmetry of Proton-Neutron Hard Elastic Scattering  

E-Print Network [OSTI]

We investigate an asymmetry in the angular distribution of hard elastic proton-neutron scattering with respect to 90deg center of mass scattering angle. We demonstrate that the magnitude of the angular asymmetry is related to the helicity-isospin symmetry of the quark wave function of the nucleon. Our estimate of the asymmetry within the quark-interchange model of hard scattering demonstrates that the quark wave function of a nucleon based on the exact SU(6) symmetry predicts an angular asymmetry opposite to that of experimental observations. On the other hand the quark wave function based on the diquark picture of the nucleon produces an asymmetry consistent with the data. Comparison with the data allowed us to extract the relative sign and the magnitude of the vector and scalar diquark components of the quark wave function of the nucleon. These two quantities are essential in constraining QCD models of a nucleon. Overall, our conclusion is that the angular asymmetry of a hard elastic scattering of baryons provides a new venue in probing quark-gluon structure of baryons and should be considered as an important observable in constraining the theoretical models.

Carlos G. Granados; Misak M. Sargsian

2009-07-29T23:59:59.000Z

419

Spatially-resolved small-angle x-ray scattering studies of soot inception and growth.  

SciTech Connect (OSTI)

The high spectral brilliance of x-rays produced at the Basic Energy Sciences Synchrotron Radiation Center of Argonne's Advanced Photon Source allows us to perform small-angle x-ray scattering (SAXS) measurements of the distributions of soot particles in flames. SAXS provides an in situ probe of the size and distribution of particles in the region between 1 and 100 nm. Detailed measurements on a propylene/air diffusion flame allow us to extract a spatially dependent background, which occurs in gas-phase combustion systems, and to perform Abel inversions, which provide the radial dependence of the scattering intensity. A bimodal distribution of soot particles is needed to describe our results. The radial behavior of the two modes of this distribution implies that the chemistry and fluid dynamics are strongly coupled in this simple diffusion flame. The larger particles of this distribution correspond to the previously observed primary particles, which have a relatively complex radial dependence. Midway between the fuel source and the widest part of the flame the primary particles have a mean radius of 6 nm or less and their concentration is symmetrically distributed about the flame front. At the widest part of the flame, two distinct distributions of primary particles are observed. Near the center of the flame the particles have a mean radius of 10 nm and a polydispersity of 0.3 and beyond a transition region they have a mean radius of 21 nm and a polydispersity of 0.2. The smaller particles, which require additional experiments before they can be identified, correspond either to soot nuclei, PAH species such as naphthalene, and/or disordered carbons with graphitic basal planes.

Hessler, J. P.; Seifert, S.; Winans, R. E.

2002-07-17T23:59:59.000Z

420

Neutron Scattering Investigations on a Bimodal Polymer Gel  

Science Journals Connector (OSTI)

As these clusters are both large and chemically different from the surrounding polymer, they scatter strongly at small values of q, thereby giving rise to the feature described by the length ?2. ... For gels swollen in octane, the scattered light and the smallest angle neutron response are dominated by scattering from aggregates of polymd. ...

Anne-Marie Hecht; Ferenc Horkay; Erik Geissler

2001-05-26T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Foams As Viewed by Small-Angle Neutron Scattering  

Science Journals Connector (OSTI)

Foams As Viewed by Small-Angle Neutron Scattering ... For wet foams, we met other difficulties, common to any strongly scattering system:? a part of the scattered beam is collected in the central cells along with the transmitted beam; this can spoil the transmission measurements. ...

Monique A. V. Axelos; François Boué

2003-07-04T23:59:59.000Z

422

NEUTRON SCATTERING EVIDENCE FOR A SPIN-PEIERLS  

E-Print Network [OSTI]

NEUTRON SCATTERING EVIDENCE FOR A SPIN-PEIERLS GROUND STATE IN (TMTTF)2PF6 J.P. POUGET, P. FOURY results · magnetic caracterisation of the samples used · neutron scattering detection of the SP;elastic neutron scattering evidence of SP superlattice reflexions in (TMTTF)2PF6 (H12) Laboratoire Léon

Paris-Sud 11, Université de

423

Twelfth National School on Neutron and X-ray Scattering  

E-Print Network [OSTI]

Twelfth National School on Neutron and X-ray Scattering June 12 � June 26, 2010 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

Pennycook, Steve

424

National School on Neutron and X-ray Scattering  

E-Print Network [OSTI]

National School on Neutron and X-ray Scattering May 30 � June 13, 2009 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

Pennycook, Steve

425

National School on Neutron and X-ray Scattering  

E-Print Network [OSTI]

15th National School on Neutron and X-ray Scattering August 10 - 24, 2013 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major Ridge National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang

426

Fourteenth National School on Neutron and X-ray Scattering  

E-Print Network [OSTI]

Fourteenth National School on Neutron and X-ray Scattering August 12 - 25, 2012 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major Ridge National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang

Pennycook, Steve

427

Nitrogen Contamination in Elastic Neutron Scattering Songxue Chi,ab  

E-Print Network [OSTI]

Nitrogen Contamination in Elastic Neutron Scattering Songxue Chi,ab Jeffrey W. Lynn,a* Ying Chen a neutron scattering measurement is a contribution to the background, especially in inelastic measurements of having N2 in the sample environment system during elastic neutron scattering measurements on a single

Lynn, Jeffrey W.

428

Thirteenth National School on Neutron and X-ray Scattering  

E-Print Network [OSTI]

Thirteenth National School on Neutron and X-ray Scattering June 11 ­ June 25, 2011 at Argonne of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

429

A Java-based Science Portal for Neutron Scattering Experiments  

E-Print Network [OSTI]

A Java-based Science Portal for Neutron Scattering Experiments Sudharshan S. Vazhkudai James A scattering facility recently commissioned by the US Department of Energy (DOE). The neutron beam produced (SNS) [14] is a large-scale leading- edge neutron scattering facility that hopes to fundamen- tally

Vazhkudai, Sudharshan

430

TUTORIAL / ARTICLE DIDACTIQUE Neutron scattering study of the classical  

E-Print Network [OSTI]

TUTORIAL / ARTICLE DIDACTIQUE Neutron scattering study of the classical antiferromagnet MnF2: a perfect hands-on neutron scattering teaching course1 Z. Yamani, Z. Tun, and D.H. Ryan Abstract: We present of neutron scattering concepts. The nature of antiferromagnetism and the magnetic Hamiltonian in this classi

Ryan, Dominic

431

Neutron Scattering Society of America Purpose and New Initiatives  

E-Print Network [OSTI]

1 Neutron Scattering Society of America (NSSA) Purpose and New Initiatives www.neutronscattering.org SNS/ANL School on Neutron and X-Ray Scattering June 2011 Visit us now on Facebook #12;2 What and provide a focal point for the neutron scattering community in the USA To identify the needs

432

The Neutron Scattering Society www.neutronscattering.org  

E-Print Network [OSTI]

The Neutron Scattering Society of America www.neutronscattering.org Press Release, February 4, 2008 The Neutron Scattering Society of America is pleased to announce the 2008 recipients of its 3 major prizes. The Neutron Scattering Society of America (NSSA) established the Clifford G. Shull Prize in Neutron Science

Chen, Sow-Hsin

433

The Neutron Scattering Society www.neutronscattering.org  

E-Print Network [OSTI]

The Neutron Scattering Society of America www.neutronscattering.org Press Release February 11, 2008 The Neutron Scattering Society of America is pleased to announce the election as Fellows of the Society of in application of neutron scattering to studies of surfaces and crystal field excitations as well as his

Homes, Christopher C.

434

Neutron scattering in magnetic fields (*) W. C. Koehler  

E-Print Network [OSTI]

691 Neutron scattering in magnetic fields (*) W. C. Koehler Solid State Division, Oak Ridge. Abstract 2014 The use of magnetic fields in neutron scattering experimentation is reviewed briefly. Two of the scattering sample ; in the second the field acts on the neutron itself. Several examples are discussed

Boyer, Edmond

435

Neutron Scattering Society of America Purpose and New Initiatives  

E-Print Network [OSTI]

1 Neutron Scattering Society of America (NSSA) Purpose and New Initiatives www.neutronscattering.org SNS/ANL School on Neutron and X-Ray Scattering June 2010 Visit us now on Facebook #12;2 What and provide a focal point for the neutron scattering community in the USA To identify the needs

Pennycook, Steve

436

ORNL Neutron Scattering School May 30 -June 5, 2009  

E-Print Network [OSTI]

ORNL Neutron Scattering School May 30 - June 5, 2009 Oak Ridge National Laboratory Oak Ridge, 2009, for the first week of the Neutron Xray Scattering School. Please be certain to bring photo for Neutron Scattering Users � Radiological Worker Training for HFIR and SNS Users In addition

Pennycook, Steve

437

Sixteenth National School on Neutron and X-ray Scattering  

E-Print Network [OSTI]

Sixteenth National School on Neutron and X-ray Scattering June 14-28, 2014 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major's Neutron Scattering Science Division. Scientific Directors: Suzanne G.E. te Velthuis, Esen Ercan Alp

Pennycook, Steve

438

Tenth National School on Neutron and X-ray Scattering  

E-Print Network [OSTI]

Tenth National School on Neutron and X-ray Scattering September 24 - October 11, 2008 at Argonne of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

Pennycook, Steve

439

Improvement of data treatment in small-angle neutron scattering  

Science Journals Connector (OSTI)

General equations are given for background subtraction of SANS treatment, which account for large scattering angles () and allow the extraction of the scattering due to the sample when the later is inside a container that displays a spurious scattering signal. Several calibration methods to determine the inherent sample backgrounds are also described.

Br?let, A.

2007-01-12T23:59:59.000Z

440

Recent Results in Diffractive ep Scattering at HERA  

E-Print Network [OSTI]

Recent Results in Diffractive ep Scattering at HERA Introduction to diffraction in ep Exclusive Diffraction in ep Scattering Matthew Beckingham 2 Diffraction Lepton-hadron (-p) or hadron-hadron (p to interpret in (p)QCD? #12;Lake Louise 06 Diffraction in ep Scattering Matthew Beckingham 3 Diffraction

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Small Angle X-ray Scattering (SAXS) Laboratory Learning Experiences  

E-Print Network [OSTI]

.A. & Svergun D.I. (1987). Structure Analysis by Small-Angle X-Ray and Neutron Scattering. NY: Plenum PressSmall Angle X-ray Scattering (SAXS) Laboratory Learning Experiences o - Use of small angle X-ray scattering instrumentation o - Programs that you will use SAXS (BRUKER AXS) PRIMUS (Konarev, Volkov, Koch

Meagher, Mary

442

Anisotropic light scattering of individual sickle red blood cells  

E-Print Network [OSTI]

Anisotropic light scattering of individual sickle red blood cells Youngchan Kim John M. Higgins blood cells (RBCs) from a patient with sickle cell disease (SCD). To measure light scattering spectra: red blood cell; sickle cell disease; light scattering; quantita- tive phase microscopy. Paper 11736L

Suresh, Subra

443

Wavelength-dependent scattering in spectroscopic optical coherence tomography  

E-Print Network [OSTI]

Wavelength-dependent scattering in spectroscopic optical coherence tomography Chenyang Xu, P. Scott of light scattering spectroscopy (LSS) and the spatial localization of optical coherence tomography (OCT.4500) Optical coherence tomography; (290.0290) Scattering; (300.0300) Spectroscopy References and links 1. A

Bhargava, Rohit

444

ccsd00002835, Light scattering from cold rolled aluminum surfaces  

E-Print Network [OSTI]

ccsd­00002835, version 2 ­ 14 Sep 2004 Light scattering from cold rolled aluminum surfaces Damien Camille Soula , 31400 Toulouse, France We present experimental light scattering measurements from aluminum scattering measurements of an s-polarized electromagnetic wave (632.8 nanometers) from a rough aluminum alloy

445

Similarity between positronium-atom and electron-atom scattering  

E-Print Network [OSTI]

We employ the impulse approximation for description of positronium-atom scattering. Our analysis and calculations of Ps-Kr and Ps-Ar collisions provide theoretical explanation of the similarity between the cross sections for positronium scattering and electron scattering for a range of atomic and molecular targets observed by S. J. Brawley et al. [Science 330, 789 (2010)].

Fabrikant, I I

2015-01-01T23:59:59.000Z

446

Small angle neutron scattering and small angle X-ray scattering studies of platinum-loaded carbon foams  

Science Journals Connector (OSTI)

The morphology of carbon nanofoam samples comprising platinum nanoparticles dispersed in the matrix was characterized by small angle neutron scattering (SANS) and small angle X-ray scattering (SAXS) techniques. R...

P. U. Sastry; V. K. Aswal; A. G. Wagh

2008-11-01T23:59:59.000Z

447

Temperature dependence of the dynamic scattering function in glycerol studied by quasi-elastic slow neutron scattering  

Science Journals Connector (OSTI)

Microscopic dynamics of glycerol across the liquid–glass transition has been studied by incoherent slow neutron scattering performed at temperatures from 400?K to ... data are analyzed in terms of the dynamic scattering

I. Padureanu; R.E. Lechner; D. Aranghel; A. Radulescu; A. Desmedt…

2002-12-01T23:59:59.000Z

448

Water and ice structure in the range 220 - 365K from radiation total scattering experiments  

E-Print Network [OSTI]

The past decade or so has witnessed a large number of articles about water structure. The most incisive experiments involve radiation with a wavelength compatible with the observed inter-molecular separations found in water, of order $\\sim 3$\\AA, in other words mostly $$10keV x-rays. Because x-rays are scattered by electrons while neutrons are scattered by nuclei, the two probes give complementary information about the three site-site radial distribution functions for water, namely O-O, O-H and H-H. Here a version of Monte Carlo simulation called Empirical Potential Structure Refinement is used to devise an empirical intermolecular potential which attempts to drive the simulated radial distribution functions as close as possible to the data. New x-ray and neutron scattering data on water in the temperature range 280 - 365K are presented for the first time, alongside a new analysis of some much older neutron data on ice 1h at 220K. This temperature analysis, above and below the water freezing point of water, r...

Soper, Alan K

2014-01-01T23:59:59.000Z

449

Coal Distribution Database, 2006  

U.S. Energy Information Administration (EIA) Indexed Site

2009 Final February 2011 2 Overview of 2009 Coal Distribution Tables Introduction The Coal Distribution Report - Annual provides detailed information on domestic coal distribution by origin state, destination state, consumer category, and method of transportation. Also provided is a summary of foreign coal distribution by coal-producing State. This Final 2009 Coal Distribution Report - Annual, supersedes the data contained in the four Quarterly Coal Distribution Reports previously issued for 2009. This report relies on the most current data available from EIA's various monthly, quarterly and annual surveys of the coal industry and electric power generation industry. In addition, the report

450

Measurement of the differential neutron-deuteron scattering cross section in the energy range from 100 keV to 600 keV using a proportional counter  

E-Print Network [OSTI]

The angular distribution of neutron-deuteron scattering was investigated using the proportional counter P2 simultaneously as scattering target and detector for the recoil deuterons. The measurements were carried out using monoenergetic neutrons in the energy range from 150 keV to 500 keV. Various techniques were employed to reduce distortions of the experimental pulse-height distribution by photon-induced events. The experimental data were compared with realistic simulations which were carried out using different evaluated data sets. This comparison allows to conclude on inconsistencies in the evaluations.

Nolte, R; Plompen, A; Röttger, S

2014-01-01T23:59:59.000Z

451

JOURNAL DE PHYSIQUE Colloque C4, supplgment au no 11-12, Tome 34, Novembre-Dtcembre 1973,page 23 NEUTRON DISTRIBUTIONS  

E-Print Network [OSTI]

,, or on the differencep, -p, bet- ween the neutron and proton distributions. These experiments include scattering NEUTRON DISTRIBUTIONS R. C. BARRETT University of Surrey, Guildford, Surrey, U. K. RBsumB. -Un rappel des calculs de distributions de densite de neutrons B partir du modtile a particules independantes, du modtile

Boyer, Edmond

452

A More Informative Approach for Characterization of Polymer Monolithic Phases: Small Angle Neutron Scattering/Ultrasmall Angle Neutron Scattering  

Science Journals Connector (OSTI)

A More Informative Approach for Characterization of Polymer Monolithic Phases: Small Angle Neutron Scattering/Ultrasmall Angle Neutron Scattering ... Scattered neutrons were detected with a 64 cm × 64 cm two-dimensional position sensitive detector with 128 × 128 pixels and 0.5 cm resolution per pixel. ...

Kathleen M. Ford; Brian G. Konzman; Judith F. Rubinson

2011-11-08T23:59:59.000Z

453

Multiple Scattering Measurements in the MICE Experiment  

SciTech Connect (OSTI)

The international Muon Ionization Cooling Experiment (MICE), under construction at RAL, will test a prototype cooling channel for a future Neutrino Factory or Muon Collider. The cooling channel aims to achieve, using liquid hydrogen absorbers, a 10% reduction in transverse emittance. The change in 4D emittance will be determined with an accuracy of 1% by measuring muons individually. Step IV of MICE will make the first precise emittance-reduction measurements of the experiment. Simulation studies using G4MICE, based on GEANT4, find a significant difference in multiple scattering in low Z materials, compared with the standard expression quoted by the Particle Data Group. Direct measurement of multiple scattering using the scintillating-fibre trackers is found to be possible, but requires the measurement resolution to be unfolded from the data.

Carlisle, T.; Cobb, J.; /Oxford U.; Neuffer, D.; /Fermilab

2012-05-01T23:59:59.000Z

454

Viscosity and Light Scattering in Critical Mixtures  

Science Journals Connector (OSTI)

Simultaneous measurements of both viscosity and light scattering are performed on two critical mixtures. The first one is a triethylamine-water solution, which exhibits a lower consolute point, the second one a methanol-ciclohexane mixture with an upper consolute point. It is found that the singular behavior of viscosity cannot be fitted by a simple power law, nor by a logarithmic one, in the entire range of temperature. The asymptotic behavior, however, tends to become logarithmic as the critical temperature is approached. The simultaneous observation of scattered light allows one to exclude the intervention of spurious processes, like a breaking of correlations because of impurities. In addition, it is shown that the correlation length seems to depend mainly on the reduced temperature, irrespective of the system under examination.

S. Ballaro'; G. Maisano; P. Migliardo; F. Wanderlingh

1972-10-01T23:59:59.000Z

455

EXPONENTIAL GALAXY DISKS FROM STELLAR SCATTERING  

SciTech Connect (OSTI)

Stellar scattering off of orbiting or transient clumps is shown to lead to the formation of exponential profiles in both surface density and velocity dispersion in a two-dimensional non-self gravitating stellar disk with a fixed halo potential. The exponential forms for both nearly flat rotation curves and near-solid-body rotation curves. The exponential does not depend on initial conditions, spiral arms, bars, viscosity, star formation, or strong shear. After a rapid initial development, the exponential saturates to an approximately fixed scale length. The inner exponential in a two-component profile has a break radius comparable to the initial disk radius; the outer exponential is primarily scattered stars.

Elmegreen, Bruce G. [IBM Research Division, T.J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, NY 10598 (United States)] [IBM Research Division, T.J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, NY 10598 (United States); Struck, Curtis, E-mail: bge@watson.ibm.com, E-mail: curt@iastate.edu [Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States)] [Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States)

2013-10-01T23:59:59.000Z

456

Optical theorem and elastic nucleon scattering  

E-Print Network [OSTI]

In the theoretical analysis of high-energy elastic nucleon scattering one starts commonly from the description based on the validity of optical theorem, which allows to derive the value of total cross section directly from the experimentally measured t-dependence of elastic differential cross section. It may be shown, however, that this theorem has been derived on the basis of one assumption that might be regarded perhaps as acceptable for long-range (e.g., Coulomb) forces but must be denoted as quite unacceptable for finite-range hadron forces. Consequently, the conclusions leading to the increase of total cross section with energy at higher collision energies must be newly analyzed. The necessity of new analysis concerns also the derivation of elastic scattering t-dependence at very low transverse momenta from measured data.

Milos V. Lokajicek; Vojtech Kundrat

2009-06-22T23:59:59.000Z

457

Study of Liquid Dynamics by Neutron Scattering  

Science Journals Connector (OSTI)

This paper reviews the information about the collective motions of atoms in liquids which can be obtained from neutron scattering experiments with particular attention to the rare gases and liquid metals. The current status of the theoretical interpretation is examined. Coherent neutron scattering from a monatomic liquid gives directly the spectrum of the correlation function for density fluctuations in the system for wavelengths in the range 1–10 Å. The results have a dual interpretation. On the one hand they may be understood in terms of a viscoelastic theory which takes into account the microscopic structure of the liquid; on the other hand fluctuations at these wavelengths may be interpreted in terms of vibrational modes as in an amorphous solid. The paper attempts to reconcile these two points of view. Qualitative differences between liquidargon and the liquid metals are discussed with reference to the connection between the neutron results and the microscopic properties of these liquids.

P. Schofield

1969-01-01T23:59:59.000Z

458

Raman scattering from sp2 carbon clusters  

Science Journals Connector (OSTI)

Raman spectra of B ion-implanted glassy carbon (GC) and hydrogenated amorphous carbon (a-C:H) films have been measured as a function of polarization direction of the scattered light and excitation wavelength. Raman bands of GC implanted heavily with a fluence of more than 5×1015 B ions/cm2 and a-C:H films show a frequency-independent depolarization ratio, suggesting the existence of sp2 carbon clusters in these samples. It was found that Raman spectra of GC implanted heavily with a fluence of more than 5×1015 B ions/cm2 varied with the excitation wavelength. From a comparative study of the heavily implanted GC and a-C:H films, the variation of the Raman spectra with the excitation wavelength observed for the heavily implanted GC is interpreted in terms of ?-?* resonant Raman scattering from sp2 carbon clusters having various sizes.

M. Yoshikawa; N. Nagai; M. Matsuki; H. Fukuda; G. Katagiri; H. Ishida; A. Ishitani; I. Nagai

1992-09-15T23:59:59.000Z

459

Scattering off an SO(10) cosmic string  

Science Journals Connector (OSTI)

The scattering of fermions from the Abelian string arising during the phase transition SO(10)?SU(5)×Z2 induced by the Higgs field in the 126 representation is studied. Elastic cross sections and baryon-number-violating cross sections due to the coupling to gauge fields in the core of the string are computed by both a first-quantized method and a perturbative second-quantized method. The elastic cross sections are found to be Aharonov-Bohm-type. However, there is a marked asymmetry between the scattering cross sections for left- and right-handed fields. The catalysis cross sections are small, depending on the grand unified scale. If cosmic strings were observed our results could help tie down the underlying gauge group.

Anne-Christine Davis and Rachel Jeannerot

1995-08-15T23:59:59.000Z

460

Adiabatic Approximation, Semiclassical Scattering, and Unidirectional Invisibility  

E-Print Network [OSTI]

The transfer matrix of a possibly complex and energy-dependent scattering potential can be identified with the $S$-matrix of a two-level time-dependent non-Hermitian Hamiltonian H(t). We show that the application of the adiabatic approximation to H(t) corresponds to the semiclassical description of the original scattering problem. In particular, the geometric part of the phase of the evolving eigenvectors of H(t) gives the pre-exponential factor of the WKB wave functions. We use these observations to give an explicit semiclassical expression for the transfer matrix. This allows for a detailed study of the semiclassical unidirectional reflectionlessness and invisibility. We examine concrete realizations of the latter in the realm of optics.

Ali Mostafazadeh

2014-01-17T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Direct Measurement of Neutron?Neutron Scattering  

Science Journals Connector (OSTI)

In order to resolve long?standing discrepancies in indirect measurements of the neutron?neutron scattering length ann and contribute to solving the problem of the charge symmetry of the nuclear force the collaboration DIANNA (Direct Investigation of ann Association) plans to measure the neutron?neutron scattering cross section ? nn . The key issue of our approach is the use of the through?channel in the Russia reactor YAGUAR with a peak neutron flux of 1018 /cm2/s. The proposed experimental setup is described. Results of calculations are presented to connect ? nn with the nn?collision detector count rate and the neutron flux density in the reactor channel. Measurements of the thermal neutron fields inside polyethylene converters show excellent prospects for the realization of the direct nn?experiment.

E. I. Sharapov; C. D. Bowman; B. E. Crawford; W. I. Furman; C. R. Howell; B. G. Levakov; V. I. Litvin; W. I. Lychagin; A. E. Lyzhin; E. P. Magda; G. E. Mitchell; G. V. Muzichka; G. V. Nekhaev; Yu. V. Safronov; V. N. Shvetsov; S. L. Stephenson; A. V. Strelkov; W. Tornow

2003-01-01T23:59:59.000Z

462

Neutron scattering in almost-classical liquids  

Science Journals Connector (OSTI)

A theory of quantum corrections for thermal-neutron scattering in almost-classical liquids is developed that goes beyond the usual quasiclassical approximations, which take only detailed balance and translational recoil into account, by also including quantum effects in the structure and dynamics of the liquid itself. The method that we use is similar to one which we have recently developed for calculating corrections for final-state interactions in deep-inelastic neutron scattering. In the present application the method requires an expansion of the moments of the dynamic structure factor in powers of ?2. We show that the required expansions can conveniently be obtained by an extension of a method due originally to Nelkin.

V. F. Sears

1985-04-01T23:59:59.000Z

463

Brillouin scattering study of molten zinc chloride  

Science Journals Connector (OSTI)

Polarized and depolarized Brillouin scattering experiments on molten ZnCl2 were performed between 300 and 600 °C in different geometries. VV spectra measured in backscattering and small angle scattering were analyzed with conventional viscoelastic theory using either a Debye or a Cole-Davidson model for the memory function. We also analyzed in the same way the temperature dependence of the transverse Brillouin lines detected in a 90° VH geometry. We show that the Cole-Davidson memory function yields a consistent interpretation of all the spectra. The resulting shear and longitudinal relaxation times are equal within their error bars, and are about 2.5 times smaller than the ? relaxation time previously determined. The static shear viscosity values deduced from the analysis of the propagating transverse waves agree, at all temperatures, with the measured viscosity values.

C. Dreyfus; M. J. Lebon; F. Vivicorsi; A. Aouadi; R. M. Pick; H. Z. Cummins

2001-03-29T23:59:59.000Z

464

Fixed target electroweak and hard scattering physics  

SciTech Connect (OSTI)

The possibilities for future physics and experiments involving weak and electromagnetic interactions, neutrino oscillations, general hard scattering and experiments involving nuclear targets were explored. The studies were limited to the physics accessible using fixed target experimentation. While some of the avenues explored turn out to be relatively unrewarding in the light of competition elsewhere in the world, there are a number of positive conclusions reached about experimentation in the energy range available to the Main Injector and Tevatron. Some of the experiments would benefit from the increased intensity available from the Tevatron utilizing the Main Injector, while some require this increase. Finally, some of the experiments would use the Main Injector low energy, high intensity extracted beams directly. A program of electroweak and hard scattering experiments at fixed target energies retains the potential for important contributions to physics. The key to major parts of this program would appear to be the existence of the Main Injector. 115 refs, 17 figs.

Brock, R. (Michigan State Univ., East Lansing, MI (USA)); Brown, C.N.; Montgomery, H.E. (Fermi National Accelerator Lab., Batavia, IL (USA)); Corcoran, M.D. (eds.) (Rice Univ., Houston, TX (USA))

1990-02-01T23:59:59.000Z

465

Inelastic neutron scattering from confined molecular oxygen  

Science Journals Connector (OSTI)

Inelastic neutron-scattering measurements were carried out on condensed bulk and confined molecular oxygen. The phase transitions of the oxygen confined in cylindrical pores with diameter of ?94?Å are suppressed below their bulk temperatures or in the case of the lowest-temperature transition to the ? phase are suppressed entirely. This last observation is possibly due to the low latent heat of transition for this transition. Both elastic and inelastic neutron-scattering data indicate a mixing of oxygen crystal phases upon confinement. Magnetic ordering fluctuations in the ? phase are found to have similar energy-dependent profiles for confined and bulk excitations showing that the magnetic correlation function decay is unaffected by the finite crystal size in confinement.

Duncan Kilburn; Paul E. Sokol; Craig M. Brown

2008-12-29T23:59:59.000Z

466

Pumping angular momentum by driven chaotic scattering  

E-Print Network [OSTI]

Chaotic scattering with an internal degree of freedom and the possibility to generate directed transport of angular momentum is studied in a specific model, a magnetic dipole moving in a periodically modulated magnetic field confined to a compact region in space. We show that this system is an irregular scatterer in large parts of its parameter space. If in addition all spatio-temporal symmetries are broken, directed transport of mass as well as angular momentum occurs. The sensitive parameter dependence of the corresponding currents includes frequent sign reversals. Zeros of either quantity entail the exclusive occurrence of the other and thus give rise in particular to angular-momentum separation without mass transport as a classical analogue of spin-polarized currents.

T. Dittrich; F. L. Dubeibe

2008-04-29T23:59:59.000Z

467

Coal Distribution Database, 2006  

U.S. Energy Information Administration (EIA) Indexed Site

Domestic Distribution of U.S. Coal by Origin State, Domestic Distribution of U.S. Coal by Origin State, Consumer, Destination and Method of Transportation, 2009 Final February 2011 2 Overview of 2009 Coal Distribution Tables Introduction The Coal Distribution Report - Annual provides detailed information on domestic coal distribution by origin state, destination state, consumer category, and method of transportation. Also provided is a summary of foreign coal distribution by coal-producing State. This Final 2009 Coal Distribution Report - Annual, supersedes the data contained in the four Quarterly Coal Distribution Reports previously issued for 2009. This report relies on the most current data available from EIA's various monthly, quarterly and annual surveys

468

CONSULTANT REPORT DISTRIBUTED GENERATION  

E-Print Network [OSTI]

Energy Jobs Plan, Governor Brown established a 2020 goal of 12,000 megawatts of localized renewable energy development, or distributed generation, in California. In May 2012, Southern California Edison, renewables, interconnection, integration, electricity, distribution, transmission, costs. Please use

469

Distributed Wind 2015  

Broader source: Energy.gov [DOE]

Distributed Wind 2015 is committed to the advancement of both distributed and community wind energy. This two day event includes a Business Conference with sessions focused on advancing the...

470

Neutron Scattering by an Anharmonic Crystal  

Science Journals Connector (OSTI)

Baym's treatment of coherent scattering of slow neutrons by a crystal is examined and modified to include effects due to the cubic-anharmonic term in the lattice potential to second order in the coupling constant. Corrections to the Debye-Waller factor and to the "one-phonon" resonance peak are obtained, which appear to be negligible (?0.01%) for the case of a Bravais lattice and certainly <1% in other cases.

B. V. Thompson

1963-08-15T23:59:59.000Z

471

Recent results from COMPASS muon scattering measurements  

SciTech Connect (OSTI)

A sample of recent results in muon scattering measurements from the COMPASS experiment at CERN will be reviewed. These include high energy processes with longitudinally polarised proton and deuteron targets. High energy polarised measurements provide important constraints for studying the nucleon spin structure and thus permit to test the applicability of the theoretical framework of factorisation theorems and perturbative QCD. Specifically, latest results on longitudinal quark polarisation, quark helicity densities and gluon polarisation will be reviewed.

Capozza, Luigi [Irfu/SPhN - CEA Saclay, 91190 Gif-sur-Yvette (France); Collaboration: COMPASS Collaboration

2012-10-23T23:59:59.000Z

472

Scatter factors assessment in microbeam radiation therapy  

SciTech Connect (OSTI)

Purpose: The success of the preclinical studies in Microbeam Radiation Therapy (MRT) paved the way to the clinical trials under preparation at the Biomedical Beamline of the European Synchrotron Radiation Facility. Within this framework, an accurate determination of the deposited dose is crucial. With that aim, the scatter factors, which translate the absolute dose measured in reference conditions (2 x 2 cm{sup 2} field size at 2 cm-depth in water) to peak doses, were assessed. Methods: Monte Carlo (MC) simulations were performed with two different widely used codes, PENELOPE and GEANT4, for the sake of safety. The scatter factors were obtained as the ratio of the doses that are deposited by a microbeam and by a field of reference size, at the reference depth. The calculated values were compared with the experimental data obtained by radiochromic (ISP HD-810) films and a PTW 34070 large area chamber. Results: The scatter factors for different microbeam field sizes assessed by the two MC codes were in agreement and reproduced the experimental data within uncertainty bars. Those correction factors were shown to be non-negligible for the future MRT clinical settings: an average 30% lower dose was deposited by a 50 {mu}m microbeam with respect to the reference conditions. Conclusions: For the first time, the scatter factors in MRT were systematically studied. They constitute an essential key to deposit accurate doses in the forthcoming clinical trials in MRT. The good agreement between the different calculations and the experimental data confirms the reliability of this challenging micrometric dose estimation.

Prezado, Y.; Martinez-Rovira, I.; Sanchez, M. [Laboratoire Imagerie et Modelisation en Neurobiologie et Cancerologie IMNC-UMR 8165, Centre National de la Recherche Scientifique (CNRS), Campus Universitaire, Bat. 440, 15 rue Georges Clemenceau, 91406 Orsay Cedex (France); Institut de Tecniques Energetiques, Universitat Politecnica de Catalunya, Diagonal 647, E-08028 Barcelona (Spain) and ID17 Biomedical Beamline, European Synchrotron Radiation Facility (ESRF), 6 Rue Jules Horowitz, B.P. 220, 38043 Grenoble Cedex (France); Servicio de Radiofisica, Complejo Hospitalario de Santiago de Compostela, Rua Choupana S/N, 15706 Santiago de Compostela (Spain)

2012-03-15T23:59:59.000Z

473

Pionic atoms and low energy elastic scattering  

SciTech Connect (OSTI)

A fit to pionic atom data is used to determine four of the parameters of the low energy pion-nucleus optical potential, while the other parameters are taken from theory. The resulting potential is used to predict elastic scattering from 30 --50 MeV pions. The effects of extrapolating the parameters to 50 MeV with a simple energy dependence are examined.

Stricker, K.; Carr, J.A.; McManus, H.

1980-11-01T23:59:59.000Z

474

Fragility by elastic incoherent neutron scattering  

Science Journals Connector (OSTI)

The present work furnishes an operative definition for the fragility degree by using elastic incoherent neutron scattering (EINS). Such a definition is based on the relation between viscosity a macroscopic quantity and the atomic mean-square displacement which refers to a nanoscopic property. This procedure has been used to analyze a set of glass-forming systems and it allows to obtain a linear dependence of the fragility parameter M obtained by EINS on the fragility parameter m obtained by viscosity measurements.

S. Magazù; G. Maisano; F. Migliardo

2004-01-01T23:59:59.000Z

475

Finite Rank Perturbations, Scattering Matrices and Inverse Problems  

E-Print Network [OSTI]

In this paper the scattering matrix of a scattering system consisting of two selfadjoint operators with finite dimensional resolvent difference is expressed in terms of a matrix Nevanlinna function. The problem is embedded into an extension theoretic framework and the theory of boundary triplets and associated Weyl functions for (in general nondensely defined) symmetric operators is applied. The representation results are extended to dissipative scattering systems and an explicit solution of an inverse scattering problem for the Lax-Phillips scattering matrix is presented.

Jussi Behrndt; Mark M. Malamud; Hagen Neidhardt

2009-02-20T23:59:59.000Z

476

Neutron scattering, a powerful tool to study clay minerals  

Science Journals Connector (OSTI)

Abstract Of the techniques used to study clay minerals, neutron scattering has become more familiar to clay scientists over the past decade. A brief account of neutron scattering theory is given in this review, followed by a description of measurements that can be made using neutron diffraction and neutron scattering spectroscopy, and especially quasi-elastic neutron scattering. Then recent examples of the application of neutron scattering methods to the study of clay minerals are presented, and finally the potential advantages of such experimental results when combined to molecular dynamics are discussed. To conclude, the potential perspectives that the European Spallation Source brings to this subject are pointed out.

Murillo L. Martins; Will P. Gates; Laurent Michot; Eric Ferrage; Virginie Marry; Heloisa N. Bordallo

2014-01-01T23:59:59.000Z

477

Volume Scattering?Strength Profiles in the Northeast Pacific Ocean  

Science Journals Connector (OSTI)

A technique is described that permits the determination of the acoustic scattering strength of the ocean volume in terms of depth frequency and time. A pod of charges is lowered together with a hydrophone to various depths in the ocean and by observing the amount of scattered energy produced by detonating units of the explosive charge pod a profile of good resolution of the scattering strength versus depths obtained. The broad?band acoustic characteristics of the charges permit the spectral characteristics of the scattered returns to be determined. Observations made over an extended time period yield the time dependence of scattering. Measurements made in the northeast Pacific Ocean are given.

J. A. Scrimger; R. G. Turner

1969-01-01T23:59:59.000Z

478

Polymeric Hydrate?Inhibitor Adsorption Measured by Neutron Scattering  

Science Journals Connector (OSTI)

18 Measured scattering from the empty sample cell Ic and background Ib is subtracted via the formula which accounts for attenuation of the scattered intensities by both cell and sample according to their measured neutron transmissions Tc and Ts, respectively. ... Because the solvated and adsorbed polymer scatter incoherently, the solution scattering term may be simply added to the others in eq 2. We model this scattering as the Debye-like structure factor due to Beaucage,22 where q* = q/[erf(kqRg/?6)]3 with k ? 1.06. ...

Jeffrey L. Hutter; H. E. King, Jr.; Min Y. Lin

2000-03-09T23:59:59.000Z

479

Seismic scattering in the subduction zone of the Middle America region  

E-Print Network [OSTI]

vi 4 Scattering of seismic waves in heterogenousvii 6 Evaluation of seismic scattering usingan alternative seismic network . .

Dominguez, Luis Antonio

2012-01-01T23:59:59.000Z

480

Scattering of Slow Neutrons from Propane Gas  

Science Journals Connector (OSTI)

Measurements of the partial differential neutron scattering cross sections for room-temperature propane gas are reported. These measurements were made at incident energies of 0.0101, 0.0254, 0.0736, and 0.102 ev at seven scattering angles between 16.3° and 84.7° using the Materials Testing Reactor phased chopper velocity selector. The data are converted to the scattering-law presentation and compared with three theoretical calculations: (a) The ideal gas, using an effective mass obtained from an average of the mass tensors for the three types of H atoms in propane, gives poor agreement. (b) The Krieger-Nelkin approximation, which includes the effect of zero-point vibrations, gives limited agreement for energy transfer less than 0.5kBT at intermediate momentum transfers. At large momentum transfers where vibrational effects become important it underestimates the cross section. (c) A modification of the Krieger-Nelkin theory that includes the effects of single-quantum transitions from the three lowest vibrational states gives better agreement. The discrepancies still present at large momentum and energy transfers are attributed to an uncertainty in the methyl-group barrier height for the three lowest energy modes, to the harmonic oscillator approximation for these modes, and to the approximate molecular orientation averaging used in the calculation.

K. A. Strong; G. D. Marshall; R. M. Brugger; P. D. Randolph

1962-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "bidirectional scattering distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Rotational motion of molecules and neutron scattering  

Science Journals Connector (OSTI)

The differential neutron scattering cross section for scattering from a rigid rotating molecule in a general isotropic medium (condensed or gas state of matter) is presented. It is based on a model which assumes the complete rotational motion to consist of a damped form of free rotations and of damped librations respectively. The two phases of rotation are assumed to be coupled to microscopic density fluctuations in the medium in such a way that densities larger than the average allow only damped librations whereas densities lower than the average allow only damped rotations. The cross section is derived with the aid of a step function formalism first used by Singwi and Sjölander. Further use is made of Sears' earlier work on rotational scattering cross sections. The resulting cross section describes the molecular motions in a range of conditions from free rotations to undamped libration including all possible intermediate damped motions. The model differs from those created earlier insofar as the rotational diffusion is not necessarily described as a motion consisting of free rotations over smaller or larger angles interrupted by brief collisions. The collisions may in the present model be replaced by shorter or longer periods of libration. Numerical calculations of the Fourier transform S 1(?) of the first rotational relaxation function F 1(t) is performed using explicit models for the librational and rotational relaxation functions and for such a choice of numerical constants that the results should describe various hypothetical rotational motions of the methane molecule.

K. E. Larsson

1973-01-01T23:59:59.000Z

482

Variational Principles for Scattering Processes. I  

Science Journals Connector (OSTI)

A systematic treatment is presented of the application of variational principles to the quantum theory of scattering.Starting from the time-dependent theory, a pair of variational principles is provided for the approximate calculation of the unitary (collision) operator that describes the connection between the initial and final states of the system. An equivalent formulation of the theory is obtained by expressing the collision operator in terms of an Hermitian (reaction) operator; variational principles for the reaction operator follow. The time-independent theory, including variational principles for the operators now used to describe transitions, emerges from the time-dependent theory by restricting the discusson to stationary states. Specialization to the case of scattering by a central force field establishes the connection with the conventional phase shift analysis and results in a variational principle for the phase shift.As an illustration, the results of Fermi and Breit on the scattering of slow neutrons by bound protons are deduced by variational methods.

B. A. Lippmann and Julian Schwinger

1950-08-01T23:59:59.000Z

483

The Scattering of 4.5- and 5.5-Mev Neutrons by Deuterons  

Science Journals Connector (OSTI)

By bombarding a thin deuterium gas target with deuterons 4.5- and 5.5-Mev neutrons were produced. Deuterons recoiling from neutron collisions in (a) a thin heavy paraffin scatterer and (b) a gas sample were detected by a double coincidence counter telescope. The angular distribution of recoiling deuterons, measured from 0° to 60° in the laboratory system, shows a sharp maximum for neutron scattering at 180° with a minimum at approximately 110° in the center-of-mass system. The ratio of the differential cross section at 180° to that at 110° is 5:1 for both energies. The experimental curves are compared with the theory of Buckingham and Massey.

E. Wantuch

1951-10-15T23:59:59.000Z

484

Simulations of gamma quanta scattering in a single module of the J-PET detector  

E-Print Network [OSTI]

This article describes simulations of scattering of annihilation gamma quanta in a strip of plastic scintillator. Such strips constitute basic detection modules in a newly proposed Positron Emission Tomography which utilizes plastic scintillators instead of inorganic crystals. An algorithm simulating chain of Compton scatterings was elaborated and series of simulations have been conducted for the scintillator strip with the cross section of 5 mm x 19 mm. Obtained results indicate that secondary interactions occur only in the case of about 8% of events and out of them only 25$\\%$ take place in the distance larger than 0.5 cm from the primary interaction. It was also established that light signals produced at primary and secondary interactions overlap with the delay which distribution is characterized by FWHM of about 40 ps.

K. Szyma?ski; P. Moskal; T. Bednarski; P. Bia?as; E. Czerwi?ski; K. Giergiel; ?. Kap?on; A. Kochanowski; G. Korcyl; J. Kowal; P. Kowalski; T. Kozik; W. Krzemie?; M. Molenda; I. Moskal; Sz. Nied?wiecki; M. Pa?ka; M. Pawlik; L. Raczy?ski; Z. Rudy; P. Salabura; N. G. Sharma; M. Silarski; A. S?omski; J. Smyrski; A. Strzelecki; P. Witkowski; W. Wi?licki; M. Zieli?ski; N. Zo?

2013-12-01T23:59:59.000Z

485

Approximate Marginalization of Absorption and Scattering in Fluorescence Diffuse Optical Tomography  

E-Print Network [OSTI]

In fluorescence diffuse optical tomography (fDOT), the reconstruction of the fluorophore concentration inside the target body is usually carried out using a normalized Born approximation model where the measured fluorescent emission data is scaled by measured excitation data. One of the benefits of the model is that it can tolerate inaccuracy in the absorption and scattering distributions that are used in the construction of the forward model to some extent. In this paper, we employ the recently proposed Bayesian approximation error approach to fDOT for compensating for the modeling errors caused by the inaccurately known optical properties of the target in combination with the normalized Born approximation model. The approach is evaluated using a simulated test case with different amount of error in the optical properties. The results show that the Bayesian approximation error approach improves the tolerance of fDOT imaging against modeling errors caused by inaccurately known absorption and scattering of the...

Mozumder, Meghdoot; Arridge, Simon; Kaipio, Jari P; d'Andrea, Cosimo; Kolehmainen, Ville

2015-01-01T23:59:59.000Z

486

Constrained gamma-Z interference corrections to parity-violating electron scattering  

SciTech Connect (OSTI)

We present a comprehensive analysis of gamma-Z interference corrections to the weak charge of the proton measured in parity-violating electron scattering, including a survey of existing models and a critical analysis of their uncertainties. Constraints from parton distributions in the deep-inelastic region, together with new data on parity-violating electron scattering in the resonance region, result in significantly smaller uncertainties on the corrections compared to previous estimates. At the kinematics of the Qweak experiment, we determine the gamma-Z box correction to be Re\\box_{gamma-Z}^V = (5.61 +- 0.36) x 10^{-3}. The new constraints also allow precise predictions to be made for parity-violating deep-inelastic asymmetries on the deuteron.

Hall, Nathan Luke [Adelaide U.; Blunden, Peter Gwithian [Manitoba U.; Melnitchouk, Wally [JLAB; Thomas, Anthony W. [Adelaide U.; Young, Ross D. [Adelaide U.

2013-07-01T23:59:59.000Z

487

Neutron-Proton Scattering in the Context of the $d^*$(2380) Resonance  

E-Print Network [OSTI]

New data on quasifree polarized neutron-proton scattering, in the region of the recently observed $d^*$ resonance structure, have been obtained by exclusive and kinematically complete high-statistics measurements with WASA at COSY. This paper details the determination of the beam polarization, checks of the quasifree character of the scattering process, on all obtained $A_y$ angular distributions and on the new partial-wave analysis, which includes the new data producing a resonance pole in the $^3D_3$-$^3G_3$ coupled partial waves at ($2380\\pm10 - i40\\pm5$) MeV -- in accordance with the $d^*$ dibaryon resonance hypothesis. The effect of the new partial-wave solution on the description of total and differential cross section data as well as specific combinations of spin-correlation and spin-transfer observables available from COSY-ANKE measurements at $T_d$ = 2.27 GeV is discussed.

Adlarson, P; Bardan, W; Bashkanov, M; Bergmann, F S; Ber?owski, M; Bhatt, H; Büscher, M; Calén, H; Ciepa?, I; Clement, H; Coderre, D; Czerwi?ski, E; Demmich, K; Doroshkevich, E; Engels, R; Erven, A; Erven, W; Eyrich, W; Fedorets, P; Föhl, K; Fransson, K; Goldenbaum, F; Goslawski, P; Goswami, A; Grigoryev, K; Gullström, C --O; Hauenstein, F; Heijkenskjöld, L; Hejny, V; Hodana, M; Höistad, B; Hüsken, N; Jany, A; Jany, B R; Jarczyk, L; Johansson, T; Kamys, B; Kemmerling, G; Khan, F A; Khoukaz, A; Kirillov, D A; Kistryn, S; Kleines, H; K?os, B; Krapp, M; Krzemie?, W; Kulessa, P; Kup??, A; Lalwani, K; Lersch, D; Lorentz, B; Magiera, A; Maier, R; Marciniewski, P; Maria?ski, B; Mikirtychiants, M; Morsch, H --P; Moskal, P; Ohm, H; Ozerianska, I; del Rio, E Perez; Piskunov, N M; Podkopa?, P; Prasuhn, D; Pricking, A; Pszczel, D; Pysz, K; Pyszniak, A; Redmer, C F; Ritman, J; Roy, A; Rudy, Z; Sawant, S; Schadmand, S; Sefzick, T; Serdyuk, V; Siudak, R; Skorodko, T; Skurzok, M; Smyrski, J; Sopov, V; Stassen, R; Stepaniak, J; Stephan, E; Sterzenbach, G; Stockhorst, H; Ströher, H; Szczurek, A; Täschner, A; Trzci?ski, A; Varma, R; Wagner, G J; Wolke, M; Wro?ska, A; Wüstner, P; Wurm, P; Yamamoto, A; Yurev, L; Zabierowski, J; Zieli?ski, M J; Zink, A; Z?oma?czuk, J; {?}upra?ski, P; {?}urek, M; Workman, R L; Briscoe, W J; Strakovsky, I I

2014-01-01T23:59:59.000Z

488

Neutron-Proton Scattering in the Context of the $d^*$(2380) Resonance  

E-Print Network [OSTI]

New data on quasifree polarized neutron-proton scattering, in the region of the recently observed $d^*$ resonance structure, have been obtained by exclusive and kinematically complete high-statistics measurements with WASA at COSY. This paper details the determination of the beam polarization, checks of the quasifree character of the scattering process, on all obtained $A_y$ angular distributions and on the new partial-wave analysis, which includes the new data producing a resonance pole in the $^3D_3$-$^3G_3$ coupled partial waves at ($2380\\pm10 - i40\\pm5$) MeV -- in accordance with the $d^*$ dibaryon resonance hypothesis. The effect of the new partial-wave solution on the description of total and differential cross section data as well as specific combinations of spin-correlation and spin-transfer observables available from COSY-ANKE measurements at $T_d$ = 2.27 GeV is discussed.

P. Adlarson; W. Augustyniak; W. Bardan; M. Bashkanov; F. S. Bergmann; M. Ber?owski; H. Bhatt; M. Büscher; H. Calén; I. Ciepa?; H. Clement; D. Coderre; E. Czerwi?ski; K. Demmich; E. Doroshkevich; R. Engels; A. Erven; W. Erven; W. Eyrich; P. Fedorets; K. Föhl; K. Fransson; F. Goldenbaum; P. Goslawski; A. Goswami; K. Grigoryev; C. --O. Gullström; F. Hauenstein; L. Heijkenskjöld; V. Hejny; M. Hodana; B. Höistad; N. Hüsken; A. Jany; B. R. Jany; L. Jarczyk; T. Johansson; B. Kamys; G. Kemmerling; F. A. Khan; A. Khoukaz; D. A. Kirillov; S. Kistryn; H. Kleines; B. K?os; M. Krapp; W. Krzemie?; P. Kulessa; A. Kup??; K. Lalwani; D. Lersch; B. Lorentz; A. Magiera; R. Maier; P. Marciniewski; B. Maria?ski; M. Mikirtychiants; H. --P. Morsch; P. Moskal; H. Ohm; I. Ozerianska; E. Perez del Rio; N. M. Piskunov; P. Podkopa?; D. Prasuhn; A. Pricking; D. Pszczel; K. Pysz; A. Pyszniak; C. F. Redmer; J. Ritman; A. Roy; Z. Rudy; S. Sawant; S. Schadmand; T. Sefzick; V. Serdyuk; R. Siudak; T. Skorodko; M. Skurzok; J. Smyrski; V. Sopov; R. Stassen; J. Stepaniak; E. Stephan; G. Sterzenbach; H. Stockhorst; H. Ströher; A. Szczurek; A. Täschner; A. Trzci?ski; R. Varma; G. J. Wagner; M. Wolke; A. Wro?ska; P. Wüstner; P. Wurm; A. Yamamoto; L. Yurev; J. Zabierowski; M. J. Zieli?ski; A. Zink; J. Z?oma?czuk; P. {?}upra?ski; M. {?}urek; R. L. Workman; W. J. Briscoe; I. I. Strakovsky

2014-08-21T23:59:59.000Z

489

On the lepton-nucleon neutral and charged current deep inelastic scattering cross sections  

E-Print Network [OSTI]

Based on the requirement in the simulation of lepton-nucleus deep inelastic scattering (DIS), we construct a fortran program LDCS 1.0 calculating the differential and total cross sections for the unpolarized charged lepton-unpolarized nucleon and neutrino-unpolarized nucleon neutral current (charged current) DIS at leading order. Any set of the experimentally fitted parton distribution functions could be employed directly. The mass of incident and scattered leptons is taken into account and the boundary conditions calculating the single differential and total cross section are studied. The calculated results well agree with the corresponding experimental data which indicating the LDCS 1.0 program is good. It is also turned out that the effect of tauon mass is not negligible in the GeV energy level.

Xing-Long Li; Yu-Liang Yan; Xiao-Mei Li; Dai-Mei Zhou; Xu Cai; Ben-Hao Sa

2014-12-17T23:59:59.000Z

490

Scattering of Spinning Test Particles by Plane Gravitational and Electromagnetic Waves  

E-Print Network [OSTI]

The Mathisson-Papapetrou-Dixon (MPD) equations for the motion of electrically neutral massive spinning particles are analysed, in the pole-dipole approximation, in an Einstein-Maxwell plane-wave background spacetime. By exploiting the high symmetry of such spacetimes these equations are reduced to a system of tractable ordinary differential equations. Classes of exact solutions are given, corresponding to particular initial conditions for the directions of the particle spin relative to the direction of the propagating background fields. For Einstein-Maxwell pulses a scattering cross section is defined that reduces in certain limits to those associated with the scattering of scalar and Dirac particles based on classical and quantum field theoretic techniques. The relative simplicity of the MPD approach and its use of macroscopic spin distributions suggests that it may have advantages in those astrophysical situations that involve strong classical gravitational and electromagnetic environments.

S Kessari; D Singh; R W Tucker; C Wang

2002-03-12T23:59:59.000Z

491

Study of the proton structure by measurements of polarization transfers in real Compton scattering at Jlab  

SciTech Connect (OSTI)

A preliminary analysis of polarization-transfer data at large scattering angle (70°), obtained in an experiment of real Compton scattering on proton, performed in Hall-C of Jefferson Lab, is presented. It is also discussed the relevance of this kind of experiments for shedding light on the non-perturbative structure of the proton, at low energy, and on the transition from the non-perturbative regime to the perturbative one, that occurs at high energy. Moreover, the possibility to extract Compton form factors and the Generalized Parton Distributions, one of the most promising theoretical tool to determine the total angular momentum contribution of quarks and gluons to nucleon spin, is emphasized.

Fanelli, Cristiano Fanelli; Cisbani, Evarostp; Hamilton, David; Salme, G.; Wojtsekhowski, Bogdan B. [JLAB

2014-03-01T23:59:59.000Z

492

Investigating the proton structure through polarization transfers in real Compton scattering processes at JLAB  

SciTech Connect (OSTI)

In the present work, preliminary results of the analysis of polarization transfers in real Compton scattering (RCS) performed in Hall-C at JLAB are presented, for data collected at large scattering angle (?{sub cm}=70{degrees}) in the experiment E07-002. A previous experiment, E99-114, has already demonstrated a complete inconsistence of its results with a pQCD mechanism at JLAB energy regime. This kind of experiment, therefore, is of crucial importance for understanding the nature of the reaction mechanism for such a simple process, involving a real photon. Furthermore, RCS experiments allow the extraction of Compton form factors and Generalized Parton Distributions (GPDs), the latter connected to the total angular momentum of the nucleon.

Fanelli, Cristiano V. [INFN/Sanita, Roma, ITALY; Cisbani, Evaristo [INFN/Sanita, Roma, ITALY; Hamilton, David J. [Glasgow University; Salme, Giovanni [Instituto Nazionale de Fisica Nucleare, Italy; Wojtsekhowski, Bogdan B. [JLAB

2014-06-01T23:59:59.000Z

493

Elimination of internal resonance problem associated with acoustic scattering by three-dimensional rigid body  

Science Journals Connector (OSTI)

In this work a simple and stable numerical method is presented utilizing the method of moments (MoM) to eliminate the internal resonance problem associated with acoustic scattering by three-dimensional rigid body subjected to a plane wave incidence. The numerical method is based on the potential theory and combines the single layer formulation (SLF) and the double layer formulation (DLF). The scattering body is approximated by planar triangular patches. For the MoM solution of SLF and DLF the basis functions have been defined with respect to the edges to approximate the unknown source distribution. These basis functions along with an efficient testing proceduregenerate accurate results at all frequencies including the characteristic frequencies. Finally the new solution method is validated with several representative examples.

B. Chandrasekhar

2004-01-01T23:59:59.000Z

494

Probing Matter Radii of Neutron-Rich Nuclei by Antiproton Scattering  

E-Print Network [OSTI]

We propose to use antiprotons to investigate the sizes of stable and neutron-rich exotic nuclei by measurements of the $\\pbar A$ absorption cross section along isotopic chains in inverse kinematics. The expected effects are studied theoretically in a microscopic model. The $\\pbar U$ optical potentials are obtained by folding free space $\\pbar N$ scattering amplitudes with HFB ground state densities and solving the scattering equations by direct integration. The mass dependence of absorption cross sections is found to follow closely the nuclear root-mean-square radii. The total absorption cross section is shown to be a superposition of cross sections describing partial absorption on neutrons and protons, respectively. Thus measuring the differential cross sections for absorption on neutrons and protons will give information on their respective distributions. In neutron-rich nuclei the outer neutron layer shields the absorption on the protons giving access to investigations of antiproton-neutron interactions in matter.

H. Lenske; P. Kienle

2005-02-21T23:59:59.000Z

495

Anisotropic Compton Scattering in LiF  

Science Journals Connector (OSTI)

Both experimental measurement and theoretical calculations of the Compton profiles of LiF indicate a significant anisotropy in the electron momentum distribution whereas published x-ray structure-factor data indicate a lack of anisotropy in the charge density. In this paper we show that momentum distributions can be orders of magnitude more sensitive to anisotropy in the electron distributions than x-ray structure factors, at least in materials where the overlap of the wave functions is small.

W. A. Reed; P. Eisenberger; F. Martino; K. -F. Berggren

1975-07-14T23:59:59.000Z

496

Elastic scattering of Dirac fermions on Schwarzschild black holes  

E-Print Network [OSTI]

Approximative analytic solutions of the Dirac equation in the Schwarzschild geometry are used for building the partial wave analysis of Dirac fermions scattered by black holes. The analytic expressions of the differential cross section and induced polarization degree are derived in terms of scattering angle, mass of the black hole, energy and mass of the fermion. We perform a graphical study of differential cross section analysing the forward/backward scattering (known also as glory scattering) and the polarization degree as functions of scattering angle. The graphical analysis shows the presence of oscillations in scattering intensity around forward/backward directions, phenomena known as spiral scattering. The energy dependence of the differential cross section is also established by using analytical and graphical methods.

Ion I. Cotaescu; Cosmin Crucean; Ciprian A. Sporea

2015-02-11T23:59:59.000Z

497

Casimir interactions between scatterers in metallic carbon nanotubes  

SciTech Connect (OSTI)

We study interactions between localized scatterers on metallic carbon nanotubes by a mapping onto a one-dimensional Casimir problem. Backscattering of electrons between localized scattering potentials mediates long-range forces between them. We model spatially localized scatterers by local and nonlocal potentials and treat simultaneously the effects of intravalley and intervalley backscattering. We find that the long-range forces between scatterers exhibit the universal power-law decay of the Casimir force in one dimension, with prefactors that control the sign and strength of the interaction. These prefactors are nonuniversal and depend on the symmetry and degree of localization of the scattering potentials. We find that local potentials inevitably lead to a coupled valley scattering problem, though by contrast nonlocal potentials lead to two decoupled single-valley problems in a physically realized regime. The Casimir effect due to two-valley scattering potentials is characterized by the appearance of spatially periodic modulations of the force.

Zhabinskaya, Dina; Mele, E. J. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

2009-10-15T23:59:59.000Z

498

Molecular anisotropy effects in carbon K-edge scattering: depolarized diffuse scattering and optical anisotropy  

SciTech Connect (OSTI)

Some polymer properties, such as conductivity, are very sensitive to short- and intermediate-range orientational and positional ordering of anisotropic molecular functional groups, and yet means to characterize orientational order in disordered systems are very limited. We demonstrate that resonant scattering at the carbon K-edge is uniquely sensitive to short-range orientation correlations in polymers through depolarized scattering at high momentum transfers, using atactic polystyrene as a well-characterized test system. Depolarized scattering is found to coexist with unpolarized fluorescence, and to exhibit pronounced anisotropy. We also quantify the spatially averaged optical anisotropy from low-angle reflectivity measurements, finding anisotropy consistent with prior visible, x-ray absorption, and theoretical studies. The average anisotropy is much smaller than that in the depolarized scattering and the two have different character. Both measurements exhibit clear spectral signatures from the phenyl rings and the polyethylene-like backbone. Discussion focuses on analysis considerations and prospects for using this depolarized scattering for studies of disorder in soft condensed matter.

Stone, Kevin H.

2014-07-14T23:59:59.000Z

499

Determination of the effective parameters of proton-$^{3}$He scattering on the basis of the neutron-triton scattering data  

E-Print Network [OSTI]

We have studied the relations between the neutron-triton scattering lengths and effective ranges and the corresponding quantities for the p --$^{3}$He scattering in the framework of the potential model with an effective nucleon-nucleus interaction in the form of a $\\delta $-shell potential. It is shown that the Coulomb renormalization of the pure nuclear scattering lengths does not change the relation well established for the n + $^{3}$H system between the lengths: $A^{1} scattering lengths which give preference to set I of the phase analysis performed by E.A. George et al. (2003), which corresponds to the inequality $A^{1}_{nc} scattering lengths.

V. P. Levashev

2008-12-22T23:59:59.000Z

500

FRIB cryogenic distribution system  

SciTech Connect (OSTI)

The Michigan State University Facility for Rare Isotope Beams (MSU-FRIB) helium distribution system has been revised to include bayonet/warm valve type disconnects between each cryomodule and the transfer line distribution system, similar to the Thomas Jefferson National Accelerator Facility (JLab) and the Spallation Neutron Source (SNS) cryogenic distribution systems. The heat loads at various temperature levels and some of the features in the design of the distribution system are outlined. The present status, the plans for fabrication, and the procurement approach for the helium distribution system are also included.

Ganni, Venkatarao [JLAB; Dixon, Kelly D. [JLAB; Laverdure, Nathaniel A. [JLAB; Knudsen, Peter N. [JLAB; Arenius, Dana M. [JLAB; Barrios, Matthew N. [Michigan State; Jones, S. [Michigan State; Johnson, M. [Michigan State; Casagrande, Fabio [Michigan State

2014-01-01T23:59:59.000Z