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in subjects: "Angular Distribution"

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Far-field radiation from a cleaved cylindrical dielectric waveguide

Angular spread in the far-field radiation pattern of a cleaved dielectric waveguide is determined from the modal structure at the surface of the waveguide using the Smythe vector integral formulation. Essential features: First, a mode exists in the fiber that has no wavelength cutoff--the so-called HE{sub 11} mode. This mode arises when non-azimuthal angular dependence of the incoming radiation is present. Second, the energy flow from this hybrid mode fills the fiber face and is not annularly s… more

Date: July 9, 1996

Creator: Cerjan, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Photon and diphoton production, and k{sub T} Effects

Isolated photon production at the D0 experiment is reviewed and recent results on di-photon production are presented.

Date: November 1, 1997

Creator: Abbott, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Resonant multiphoton ionization spectra of molecules and molecular fragments. Technical progress report

objectives of this research are the development and application of theoretical techniques for studying several resonant multiphoton ionization processes in molecules. Specific problems of interest pertain to experimental studies of such spectra in which the photoelectron energy and angular distributions are determined.

Date: July 1, 1997

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Jet Production at D0

We report on preliminary measurements of the central ({vert_bar}{eta}{vert_bar}<0.5) inclusive jet cross section and the dijet angular distributions ({vert_bar}{eta}{vert_bar}<3) at {radical}s=1.8 TeV. The data were collected during the 1992-1993 and 1994-1995 runs at the Fermilab Tevatron p{anti p} Collider with the D0 detector. The measurements are in excellent agreement with next-to- leading order (NLO) QCD. Given the assumptions implicit in the theoretical models, we exclude quark composite… more

Date: August 1, 1997

Creator: Elvira, V. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurements of Branching Fractions and CP Asymmetries and Studies of Angular Distributions for B to phi phi K Decays

We present branching fraction and CP asymmetry measurements as well as angular studies of B {yields} {phi}{phi}K decays using 464 x 10{sup 6} B{bar B} events collected by the BABAR experiment. The branching fractions are measured in the {phi}{phi} invariant mass range below the {eta}{sub c} resonance (m{sub {phi}{phi}} < 2.85 GeV). We find {Beta}(B{sup +} {yields} {phi}{phi}K{sup +}) = (5.6 {+-} 0.5 {+-} 0.3) x 10{sup -6} and {Beta}(B{sup 0} {yields} {phi}{phi}K{sup 0}) = (4.5 {+-} 0.8 {+-} … more

Date: August 15, 2011

Creator: Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Single- and Two-Photon-Induced Processes at the B Factories

We discuss single- and two-photon-induced processes in e{sup +}e{sup -} annihilations with center-of-mass energy near 10.58 GeV from the BaBar and Belle experiments. In particular, we present experimental results from two-photon physics of {gamma}{gamma} {yields} {pi}{sup 0}{pi}{sup 0} and {gamma}{gamma}* {yields} {pi}{sup 0}. We also review the observation of the Two-Virtual-Photon-Annihilation process (e{sup +}e{sup -} {yields} {rho}{sup 0}{rho}{sup 0} and e{sup +}e{sup -} {yields} {phi}{rho}… more

Date: June 15, 2012

Creator: Li, Selina Z.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The Simplest Double Slit: Interference and Entanglement in Double Photoionization of H2

The wave nature of particles is rarely seen in nature. One reason is their very short de Broglie wavelengths in most situations. However, even with wavelengths close to the size of their surroundings, they couple to their environment, e.g. by gravity, Coulomb interaction, or thermal radiation. These couplings shift the phase of the waves, often in an uncontrolled way, hence yielding varying amounts of decoherence i.e. loss of phase integrity. Decoherence is thought to be a main cause of the tra… more

Date: September 18, 2007

Creator: Akoury , D.; Kreidi, K.; Jahnke , T.; Weber, Th.; Staudte , A.; Schoffler, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Large-Angular-Scale Anisotropy in the Cosmic BackgroundRadiation

We report the results of an extended series of airborne measurements of large-angular-scale anisotropy in the 3 K cosmic background radiation. Observations were carried out with a dual-antenna microwave radiometer operating at 33 GHz (0.89 cm wavelength) flown on board a U-2 aircraft to 20 km altitude. In eleven flights, between December 1976 and May 1978, the radiometer measured differential intensity between pairs of directions distributed over most of the northern hemisphere with an rms sens… more

Date: May 1, 1980

Creator: Gorenstein, M. V. & Smoot, G. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of the asymmetry in the decay Antiomega+ ---> Antilambda K+ ---> anti-p pi+ K+

The asymmetry in the {bar p} angular distribution in the sequential decay {bar {Omega}}{sup +} {yields} {bar {Lambda}}K{sup +} {yields} {bar p}{pi}{sup +}K{sup +} has been measured to be {bar {alpha}}{sub {Omega}}{bar {alpha}}{sub {Lambda}} = [+1.16{+-}0.18(stat){+-}0.17(syst)]x10{sup -2} using 1.89x10{sup 6} unpolarized {bar {Omega}}{sup +} decays recorded by the Hyper CP (E871) experiment at Fermilab. Using the known value of {alpha}{sub {Lambda}}, and assuming that {bar {alpha}}{sub {Lambda}… more

Date: January 1, 2006

Creator: Lu, L. C.; Burnstein, R. A.; Chakravorty, A.; Chen, Y. C.; Choong, W. S.; Clark, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Neutron Production by Muon Spallation I: Theory

We describe the physics and codes developed in the Muon Physics Package. This package is a self-contained Fortran90 module that is intended to be used with the Monte Carlo package MCNPX. We calculate simulated energy spectra, multiplicities, and angular distributions of direct neutrons and pions from muon spallation.

Date: November 13, 2006

Creator: Luu, T & Hagmann, C

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Regularities of Angular Distribution of Near-Horizon Sky Brightness in the Cloudless Atmosphere

The methods of sun-photometry of the atmosphere based, for example, on interpretation of the angular distribution of radiation in the solar almucantar are widely used for retrieval of the aerosol optical characteristics. Preliminary analysis has shown that the near-horizon region also can be interesting for solving some applied problems. As is known, investigations of the structure of the daytime cloudless sky brightness at observation from the ground were carried out principally at zenith angl… more

Date: March 18, 2005

Creator: Sakerin, S. M.; Zhuraleva, T. B. & Nasrtdinov, I. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Angular Distribution of Particles Emerging from a Diffusive Region and its Implications for the Fleck-Canfield Random Walk Algorithm for Implicit Monte Carlo Radiation Transport

We present various approximations for the angular distribution of particles emerging from an optically thick, purely isotropically scattering region into a vacuum. Our motivation is to use such a distribution for the Fleck-Canfield random walk method [1] for implicit Monte Carlo (IMC) [2] radiation transport problems. We demonstrate that the cosine distribution recommended in the original random walk paper [1] is a poor approximation to the angular distribution predicted by transport theory. Th… more

Date: July 3, 2000

Creator: Cooper, M. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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CONTROL SYSTEM FOR X-RAY DIFFRACTOMETER SCANNING

No Description Available.

Date: August 1, 1966

Creator: Cook, Jr, L H

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Angular distributions of high-order ATI

The above-threshold ionization (ATI), a strong-field behavior, can be studied using kilohertz lasers. This paper reports a study of electron angular distributions (AD) for Xe and Kr excited by a 50 ps, 1.05 {mu}m strong field. ADs are presented for ATI orders up to 30 and show a new intensity-dependent structure. A physical picture is proposed that has its source in one-electron, and not two-electron, dynamics. 2 figs, 5 refs.

Date: August 1, 1993

Creator: Yang, Baorui; Walker, B.; DiMauro, L. F.; Schafer, K. J.; Kulander, K. C. & Agostini, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Strange-Particle Production by 1170-MeV/c pi- Mesons

Production of {Lambda} + K{sup 0}, {Sigma}{sup 0} + K{sup 0}, and {Sigma}{sup -} + K{sup +} by 1170-MeV/c {pi}{sup -} mesons has been studied in the Lawrence Radiation Laboratory 72-inch hydrogen bubble chamber, Cross sections, angular distributions, and polarizations are presented. The polarization of the {Sigma}{sup 0} is determined at four center-of-mass angles and found to be small everywhere. Based on published results for the reaction {pi}{sup +} + p {yields} {Sigma}{sup +}, K{sup +}, a c… more

Date: May 27, 1963

Creator: Anderson, Jared Arnold

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

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The Diffusion of Fast Neutrons

From American Nuclear Society Meeting, New York, Nov. 1963. The use of the asymptotic solution to the one-velocity transport equation is considered. The angular distribution for fast neutron elastic scattering by heavy elements is discussed. An exponential angular distribution on is assumed to simplify the decay length calculation. The diffusion length of 1 to 15 Mev neutrons in iron is calculated, as well as the vector flux angular dependence. The asymptotic solution for an arbitrary angular d… more

Date: November 1963

Creator: Francis, N. C.; Brooks, E. J. & Watson, R. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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CRYSTAL GEOMETRY COMPUTER PROGRAM

A program which calculates various relationships of crystal geometry was prepared in FORTRAN notation for use with the IBM-704 computer. The primary outputs are the angles between planes, and the angles between directions, that are required to construct standard stereographic projections for any of the seven crystal systems. Values are tabulated for interplanar spacing, area of the unit parallelogram on a lattice plane, and the distance between identical points along a lattice direction. The re… more

Date: October 1, 1962

Creator: Bush, Lawrence P. & Lloyd, Lowell T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Excited charmed mesons

The experimental status of excited charmed mesons is reviewed and is compared to theoretical expectations. Six states have been observed and their properties are consistent with those predicted for excited charmed states with orbital angular momentum equal to one.

Date: May 1, 1995

Creator: Butler, J.N. & Shukla, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Searches for new physics at the Tevatron

This paper summarizes searches at the Fermilab Tevatron for a wide variety of signatures for physics beyond the Standard Model. These include searches for supersymmetric particles, in the two collider detectors and in one fixed target experiment. Also covered are searches for leptoquarks, dijet resonances, heavy gauge bosons, and particles from a fourth generation, as well as searches for deviations from the Standard Model predictions in dijet angular distributions, dilepton mass distributions,… more

Date: January 1997

Creator: Merritt, K. Wyatt

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Photon Beam Polarization and Non-Dipolar Angular Distributions

Angular distributions of ejecta from unoriented atoms and molecules depend upon the polarization state of the incident x-rays as well as upon the dynamics of the physical systems being studied. I recommend a simple geometrical way of looking at the polarization and its effects upon angular distributions. The polarization is represented as a vector in a parameter space that faithfully represents the polarization of the beam. The simple dependence of the angular dependence of the angular distribu… more

Date: August 1, 1996

Creator: Peshkin, Murray

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Internal Energy Dependence of Molecular Condensation Coefficients Determined From Molecular Beam Surface Scattering Experiments

An experiment was performed which confirms the existence of an internal mode dependence of molecular sticking probabilities for collisions of molecules with a cold surface. The scattering of a velocity selected effusive beam of CCl{sub 4} from a 90 K CC1{sub 4} ice surface has been studied at five translational velocities and for two different internal temperatures. At a surface temperature of 90 K (approx. 99% sticking probability) a four fold increase in reflected intensity was observed for t… more

Date: May 1, 1978

Creator: Sibener, S.J. & Lee, Y.T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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TABLE OF TRIM DISCRETE QUADRATURE PARAMETERS FOR THIN BINARY SLAB CELLS

Discrete quadrature weights and angles for use in discrete ordinate methods of solutions for thin cells were tabulated for a series of regional cell thicknesses of applicability. Parameters are given for 4, 8, 8, 10, and 12 angle approximations. The quadrature assignment was based upon a simplified integral transport solution to the spatial average of the angular distribution of uncollided flux, assuming flat sources. The quadrature assignments are designated TRIM, for thin-region integral meth… more

Date: September 1, 1962

Creator: Meneghetti, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Angular Distributions in the Decays B to K*l+l-

The authors use a sample of 384 million B{bar B} events collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider to study angular distributions in the rare decays B {yields} K*{ell}{sup +}{ell}{sup -}, where {ell}{sup +}{ell}{sup -} is either e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -}. For low dilepton invariant masses, m{sub {ell}{ell}} < 2.5 GeV/c{sup 2}, they measure a lepton forward-backward asymmetry {Alpha}{sub FB} = 0.24{sub -0.23}{sup +0.18} {+-} 0.05 and K* longitud… more

Date: May 2, 2008

Creator: Collaboration, The BABAR & Aubert, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Collider Signals Of Top Quark Flavor Violation From A Warped ExtraDimension

We study top quark flavor violation in the framework of a warped extra dimension with the Standard Model (SM) fields propagating in the bulk. Such a scenario provides solutions to both the Planck-weak hierarchy problem and the flavor puzzle of the SM without inducing a flavor problem. We find that, generically, tcZ couplings receive a huge enhancement, in particular the right handed ones can be {Omicron}(1%). This results in BR (t {yields} cZ) at or above the sensitivity of the Large Hadron Col… more

Date: August 29, 2006

Creator: Agashe, Kaustubh; Perez, Gilad & Soni, Amarjit

Item Type: Article

Partner: UNT Libraries Government Documents Department