98 research outputs found

    Observation of Bell Inequality violation in B mesons

    Full text link
    A pair of B0Bˉ0B^0\bar B^0 mesons from Υ(4S)\Upsilon(4S) decay exhibit EPR type non-local particle-antiparticle (flavor) correlation. It is possible to write down Bell Inequality (in the CHSH form: S2S\le2) to test the non-locality assumption of EPR. Using semileptonic B0B^0 decays of Υ(4S)\Upsilon(4S) at Belle experiment, a clear violation of Bell Inequality in particle-antiparticle correlation is observed: S=2.725+-0.167(stat)+-0.092(syst)Comment: Conference Proceeding for Garda Lake Workshop 2003 "Mysteries, Puzzles and Paradoxes in Quantum Mechanics

    Polarization Correlations of 1S0 Proton Pairs as Tests of Bell and Wigner Inequalities

    Full text link
    In an experiment designed to overcome the loophole of observer dependent reality and satisfying the counterfactuality condition, we measured polarization correlations of 1S0 proton pairs produced in 12C(d,2He) and 1H(d,He) reactions in one setting. The results of these measurements are used to test the Bell and Wigner inequalties against the predictions of quantum mechanics.Comment: 8 pages, 4 figure

    Generation of Continuous Variable Einstein-Podolsky-Rosen Entanglement via the Kerr Nonlinearity in an Optical Fibre

    Get PDF
    We report on the generation of a continuous variable Einstein-Podolsky-Rosen (EPR) entanglement using an optical fibre interferometer. The Kerr nonlinearity in the fibre is exploited for the generation of two independent squeezed beams. These interfere at a beam splitter and EPR entanglement is obtained between the output beams. The correlation of the amplitude (phase) quadratures are measured to be 4.0+-0.2 (4.0+-0.4) dB below the quantum noise limit. The sum criterion for these squeezing variances 0.80+-0.03 < 2 verifies the nonseparability of the state. The product of the inferred uncertainties for one beam 0.64+-0.08 is well below the EPR limit of unity.Comment: RevTeX, 4 pages, 3 figures, to be published in Phys. Rev. Let

    Long range absorption in the scattering of 6He on 208Pb and 197Au at 27 MeV

    Get PDF
    Quasi-elastic scattering of 6He at E_lab=27 MeV from 197Au has been measured in the angular range of 6-72 degrees in the laboratory system employing LEDA and LAMP detection systems. These data, along with previously analysed data of 6He + 208Pb at the same energy, are analyzed using Optical Model calculations. The role of Coulomb dipole polarizability has been investigated. Large imaginary diffuseness parameters are required to fit the data. This result is an evidence for long range absorption mechanisms in 6He induced reactions.Comment: 10 pages, 10 figures, minor corrections. To appear in Nucl. Phys.

    Runaway electron energy measurement using hard x-ray spectroscopy in "Damavand" tokamak

    Get PDF
    Set of experiments has been developed to study existing runaway electrons in "Damavand" tokamak plasma upon characteristics of hard x-ray emissions produced by collision of the runaway electrons with the plasma particles and limiters. As a first step, spatial distribution of hard x-ray emissions on the equatorial plane of the torus was considered. Obtained spectra of hard x-ray emissions for different alignments of shielded detector indicate isotropic emissivity in the equatorial plane. This is in agreement with wide angle cone of bremsstrahlung radiations, deduced from the mean value of energy of the runaway electrons. The mean energy was calculated from the slope of the energy spectrum of hard x-ray photons. In the second stage in order to investigate time evolution of energy of the runaway electrons, similar technique were applied to obtain hard x-ray energy in every 3 ms intervals, from the beginning to the end of plasma. The mean energy of the runaway electrons increases during the ramp up phase and reaches its maximum between 3 and 9 ms after plasma formation. Also considering the time dependence of the counted photons in each energy range shows that energetic photons are emitted during the ramp up phase of the plasma current in Damavand tokamak

    Cooling the Collective Motion of Trapped Ions to Initialize a Quantum Register

    Full text link
    We report preparation in the ground state of collective modes of motion of two trapped 9Be+ ions. This is a crucial step towards realizing quantum logic gates which can entangle the ions' internal electronic states. We find that heating of the modes of relative ion motion is substantially suppressed relative to that of the center-of-mass modes, suggesting the importance of these modes in future experiments.Comment: 5 pages, including 3 figures. RevTeX. PDF and PostScript available at http://www.bldrdoc.gov/timefreq/ion/qucomp/papers.htm . final (published) version. Eq. 1 and Table 1 slightly different from original submissio

    A compilation of charged-particle induced thermonuclear reaction rates

    Get PDF
    Low-energy cross section data for 86 charged-particle induced reactions involving light (1 less than or equal to Z less than or equal to 14), mostly stable, nuclei are compiled. The corresponding Maxwellian-averaged thermonuclear reaction rates of relevance in astrophysical plasmas at temperatures in the range from 10(6) K to 10(10) K are calculated. These evaluations assume either that the target nuclei are in their ground state, or that the target states are thermally populated following a Maxwell-Boltzmann distribution, except in some cases involving isomeric states. Adopted values complemented with lower and upper limits of the rates are presented in tabular form. Analytical approximations to the adopted rates, as well as to the inverse/direct rate ratios, are provided. (C) 1999 Elsevier Science B.V. All rights reserved

    Matching of the H- beam to the low and medium energy section of the CERN Linac4

    No full text
    Linac4 is the near future 160 MeV H- linear accelerator of the CERN presently under construction. It will replace the present Linac2 as injector of the proton accelerator complex in CERN. The Linac4 is composed of a 45 keV ion source, a Low Energy Beam Transport (LEBT), a 352.2 MHz Radio Frequency Quadrupole (RFQ), which accelerates the beam to 3 MeV, and a Medium Energy Beam Transport (MEBT), housing a beam chopper, has been installed and commissioned in the Linac4 tunnel. The LEBT is composed of two solenoids and a diagnostic box; the MEBT is composed of three Radio Frequency (RF) cavities and 11 quadrupole magnets to match and transfer the beam from the source to the RFQ and DTL, respectively. In this paper, the beam matching process of the 45 keV H- beam to the RFQ and that of accelerated 3 MeV beam to the DTL has been presented. The MEBT beam commissioning was complemented with the emittance measurement of the DTL matched beam taken with a slit-and-grid emittance measurement device located after the MEBT line &nbsp
    corecore