Author
Z. E. Meziani
Other affiliations: Temple University
Bio: Z. E. Meziani is an academic researcher from Stanford University. The author has contributed to research in topics: Nucleon & Scattering. The author has an hindex of 23, co-authored 70 publications receiving 2312 citations. Previous affiliations of Z. E. Meziani include Temple University.
Topics: Nucleon, Scattering, Proton, Inelastic scattering, Neutron
Papers published on a yearly basis
Papers
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TL;DR: The physics case, the resulting detector requirements, and the evolving detector concepts for the experimental program at the Electron-Ion Collider are described, providing the basis for a world-class experimental program that aims to increase the understanding of the fundamental structure of all visible matter.
Abstract: This report describes the physics case, the resulting detector requirements, and the evolving detector concepts for the experimental program at the Electron-Ion Collider (EIC). The EIC will be a powerful new high-luminosity facility in the United States with the capability to collide high-energy electron beams with high-energy proton and ion beams, providing access to those regions in the nucleon and nuclei where their structure is dominated by gluons. Moreover, polarized beams in the EIC will give unprecedented access to the spatial and spin structure of the proton, neutron, and light ions. The studies leading to this document were commissioned and organized by the EIC User Group with the objective of advancing the state and detail of the physics program and developing detector concepts that meet the emerging requirements in preparation for the realization of the EIC. The effort aims to provide the basis for further development of concepts for experimental equipment best suited for the science needs, including the importance of two complementary detectors and interaction regions. This report consists of three volumes. Volume I is an executive summary of our findings and developed concepts. In Volume II we describe studies of a wide range of physics measurements and the emerging requirements on detector acceptance and performance. Volume III discusses general-purpose detector concepts and the underlying technologies to meet the physics requirements. These considerations will form the basis for a world-class experimental program that aims to increase our understanding of the fundamental structure of all visible matter
304 citations
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Tohoku University1, Stanford University2, University of Pennsylvania3, American University4, California Institute of Technology5, University of Virginia6, University of Wisconsin-Madison7, University of Massachusetts Amherst8, University of Mississippi9, University of Michigan10, University of Liverpool11, Lawrence Livermore National Laboratory12, Thomas Jefferson National Accelerator Facility13, University of Bonn14, University of Basel15, Naval Postgraduate School16, College of William & Mary17, Old Dominion University18, Temple University19, Kent State University20, Florida International University21, CERN22
TL;DR: In this paper, the authors reported measurements of the proton and deuteron spin structure functions at beam energies of 29.1, 16.2, and 9.7 GeV.
Abstract: Measurements are reported of the proton and deuteron spin structure functions ${g}_{1}^{p}$ and ${g}_{1}^{d}$ at beam energies of 29.1, 16.2, and 9.7 GeV, and ${g}_{2}^{p}$ and ${g}_{2}^{d}$ at a beam energy of 29.1 GeV. The integrals ${\ensuremath{\Gamma}}_{p}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{p}{(x,Q}^{2})dx$ and ${\ensuremath{\Gamma}}_{d}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{d}{(x,Q}^{2})dx$ were evaluated at fixed ${Q}^{2}=3(\mathrm{GeV}{/c)}^{2}$ using the full data set to yield ${\ensuremath{\Gamma}}_{p}=0.132\ifmmode\pm\else\textpm\fi{}0.003(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009(\mathrm{syst})$ and ${\ensuremath{\Gamma}}_{d}=0.047\ifmmode\pm\else\textpm\fi{}0.003\ifmmode\pm\else\textpm\fi{}0.006.$ The ${Q}^{2}$ dependence of the ratio ${g}_{1}{/F}_{1}$ was studied and found to be small for ${Q}^{2}g1(\mathrm{GeV}{/c)}^{2}.$ Within experimental precision the ${g}_{2}$ data are well described by the twist-2 contribution, ${g}_{2}^{\mathrm{WW}}.$ Twist-3 matrix elements were extracted and compared to theoretical predictions. The asymmetry ${A}_{2}$ was measured and found to be significantly smaller than the positivity limit $\sqrt{R}$ for both proton and deuteron targets. ${A}_{2}^{p}$ is found to be positive and inconsistent with zero. Measurements of ${g}_{1}$ in the resonance region show strong variations with $x$ and ${Q}^{2},$ consistent with resonant amplitudes extracted from unpolarized data. These data allow us to study the ${Q}^{2}$ dependence of the integrals ${\ensuremath{\Gamma}}_{p}$ and ${\ensuremath{\Gamma}}_{n}$ below the scaling region.
295 citations
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Tohoku University1, Stanford University2, University of Pennsylvania3, American University4, University of Virginia5, University of Wisconsin-Madison6, University of Massachusetts Amherst7, DSM8, University of Michigan9, Lawrence Livermore National Laboratory10, University of Basel11, Naval Postgraduate School12, Thomas Jefferson National Accelerator Facility13, University of Liverpool14, College of William & Mary15, Old Dominion University16, Temple University17, Kent State University18, University of Bonn19, CERN20
TL;DR: In this article, the authors measured the ratio [ital g][sup [ital p]][sub 1]/[ital F][sup[ital p]-sub 1]-over the range 0.8 and 1.10 using deep-inelastic scattering of polarized electrons from polarized ammonia.
Abstract: We have measured the ratio [ital g][sup [ital p]][sub 1]/[ital F][sup [ital p]][sub 1] over the range 0.029[lt][ital x][lt]0.8 and 1.3[lt][ital Q][sup 2][lt]10 (GeV/[ital c])[sup 2] using deep-inelastic scattering of polarized electrons from polarized ammonia. An evaluation of the integral [integral][ital g][sup [ital p]][sub 1]([ital x],[ital Q][sup 2])[ital dx] at fixed [ital Q][sup 2]=3 (GeV/[ital c])[sup 2] yields 0.127[plus minus]0.004(stat)[plus minus]0.010(syst), in agreement with previous experiments, but well below the Ellis-Jaffe sum rule prediction of 0.160[plus minus]0.006. In the quark-parton model, this implies [Delta][ital q]=0.27[plus minus]0.10.
236 citations
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Stanford University1, Lawrence Livermore National Laboratory2, American University3, University of Wisconsin-Madison4, Blaise Pascal University5, Princeton University6, University of Michigan7, Syracuse University8, California Institute of Technology9, Old Dominion University10, Temple University11, Kent State University12, University of California, Berkeley13, National Institute of Standards and Technology14
TL;DR: The neutron longitudinal and transverse asymmetries have been extracted from deep inelastic scattering of polarized electrons by a polarized $^3$He target at incident energies of 19.42, 22.66 and 25.51 GeV.
Abstract: The neutron longitudinal and transverse asymmetries ${A}_{1}^{n}$ and ${A}_{2}^{n}$ have been extracted from deep inelastic scattering of polarized electrons by a polarized $^{3}\mathrm{He}$ target at incident energies of 19.42, 22.66, and 25.51 GeV. The measurement allows for the determination of the neutron spin structure functions ${g}_{1}^{n}(x, {Q}^{2})$ and ${g}_{2}^{n}(x, {Q}^{2})$ over the range $0.03lxl0.6$ at an average ${Q}^{2}$ of 2 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$. The data are used for the evaluation of the Ellis-Jaffe and Bjorken sum rules. The neutron spin structure function ${g}_{1}^{n}(x, {Q}^{2})$ is small and negative within the range of our measurement, yielding an integral $\ensuremath{\int}{0.03}^{0.6}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.028\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{syst})$. Assuming Regge behavior at low $x$, we extract ${\ensuremath{\Gamma}}_{1}^{n}=\ensuremath{\int}{0}^{1}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.031\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009 (\mathrm{syst})$. Combined with previous proton integral results from SLAC experiment E143, we find ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.160\ifmmode\pm\else\textpm\fi{}0.015$ in agreement with the Bjorken sum rule prediction ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.176\ifmmode\pm\else\textpm\fi{}0.008$ at a ${Q}^{2}$ value of 3 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$ evaluated using ${\ensuremath{\alpha}}_{s}=0.32\ifmmode\pm\else\textpm\fi{}0.05$.
227 citations
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TL;DR: Deepinelastic electron scattering from /sup 40/Ca, /sup 48/Ca and /sup 56/Fe has been measured at 60/sup 0, 90/Sup 0, and 140/sup0/ and at inelasticities up to and including the 3,3 region as discussed by the authors.
Abstract: Deep-inelastic electron scattering from /sup 40/Ca, /sup 48/Ca, and /sup 56/Fe has been measured at 60/sup 0/, 90/sup 0/, and 140/sup 0/ and at inelasticities up to and including the ..delta..(3,3) region. Longitudinal response functions in the momentum interval 300 MeV/c
202 citations
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TL;DR: The authors give an exposition of Shor's algorithm together with an introduction to quantum computation and complexity theory, and discuss experiments that may contribute to its practical implementation.
Abstract: Current technology is beginning to allow us to manipulate rather than just observe individual quantum phenomena. This opens up the possibility of exploiting quantum effects to perform computations beyond the scope of any classical computer. Recently Peter Shor discovered an efficient algorithm for factoring whole numbers, which uses characteristically quantum effects. The algorithm illustrates the potential power of quantum computation, as there is no known efficient classical method for solving this problem. The authors give an exposition of Shor's algorithm together with an introduction to quantum computation and complexity theory. They discuss experiments that may contribute to its practical implementation. [S0034-6861(96)00303-0]
1,079 citations
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TL;DR: In this article, the authors present a review of the application of atomic physics to address important challenges in physics and to look for variations in the fundamental constants, search for interactions beyond the standard model of particle physics and test the principles of general relativity.
Abstract: Advances in atomic physics, such as cooling and trapping of atoms and molecules and developments in frequency metrology, have added orders of magnitude to the precision of atom-based clocks and sensors. Applications extend beyond atomic physics and this article reviews using these new techniques to address important challenges in physics and to look for variations in the fundamental constants, search for interactions beyond the standard model of particle physics, and test the principles of general relativity.
1,077 citations
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Thomas Jefferson National Accelerator Facility1, Hampton University2, University of Paris-Sud3, University of Santiago, Chile4, Brookhaven National Laboratory5, University of Pavia6, University of Groningen7, Federico Santa María Technical University8, Shandong University9, Goethe University Frankfurt10, Stony Brook University11, Baruch College12, Duke University13, Argonne National Laboratory14, The Catholic University of America15, Old Dominion University16, Lawrence Berkeley National Laboratory17, Ohio State University18, University of Zagreb19, University of Jyväskylä20, Tel Aviv University21, CERN22, Temple University23, Massachusetts Institute of Technology24, Columbia University25, Ruhr University Bochum26, California Institute of Technology27, University of Massachusetts Amherst28, University of Buenos Aires29, University of the Basque Country30, University of Connecticut31, University of Tübingen32, Pennsylvania State University33, Stanford University34, Dalhousie University35, Central China Normal University36
TL;DR: In this article, the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community, is presented.
Abstract: This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics over the past decades and, in particular, the focused ten-week program on “Gluons and quark sea at high energies” at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them. It has been benefited profoundly from inputs by the users’ communities of BNL and JLab. This White Paper offers the promise to propel the QCD science program in the US, established with the CEBAF accelerator at JLab and the RHIC collider at BNL, to the next QCD frontier.
1,022 citations
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TL;DR: In this article, the experimentally determined properties of energy levels of A = 21−44 nuclei are compiled and evaluated with emphasis on nuclear spectroscopy, and the available information on excitation energies, spins, parities, isospins, lifetimes or widths and observed decay is summarized in a master table.
593 citations
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TL;DR: The first measurement of the parity-violating asymmetry A(PV) in the elastic scattering of polarized electrons from 208Pb is reported, which provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.
Abstract: 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 (R(n)). The result A(PV)=0.656±0.060(stat)±0.014(syst) ppm corresponds to a difference between the radii of the neutron and proton distributions R(n)-R(p)=0.33(-0.18)(+0.16) fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.
475 citations