Download or read book Evidence for Quark hadron Duality in the Proton Spin Asymmetry A1 written by A. Airapetian and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hadron Structure in Electroweak Precision Measurements written by Nathan L. Hall and published by Springer. This book was released on 2015-07-24 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis examines the γZ box contribution to the weak charge of the proton. Here, by combining recent parity-violating electron-deuteron scattering data with our current understanding of parton distribution functions, the author shows that one can limit this model dependence. The resulting construction is a robust model of the γγ and γZ structure functions that can also be used to study a variety of low-energy phenomena. Two such cases are discussed in this work, namely, the nucleon’s electromagnetic polarizabilities and quark-hadron duality. By using phenomenological information to constrain the input structure functions, this important but previously poorly understood radiative correction is determined at the kinematics of the parity-violating experiment, QWEAK, to a degree of precision more than twice that of the previous best estimate. A detailed investigation into available parametrizations of the electromagnetic and interference cross-sections indicates that earlier analyses suffered from the inability to correctly quantify their model dependence.
Download or read book Spin 2004 Proceedings Of The 16th International Spin Physics Symposium And Workshop On Polarized Electron Sources And Polarimeters With Cd rom written by Franco Bradamante and published by World Scientific. This book was released on 2005-08-02 with total page 1065 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive volume covers the most recent advances in the field of spin physics, including the latest research in high energy and nuclear physics and the study of nuclear spin structure. The comprehensive coverage also includes polarized proton and electron acceleration and storage as well as polarized ion sources and targets. Many significant new results and achievements on the different topics considered at the symposium are presented in this book for the first time.
Download or read book Theoretical Nuclear Physics In Italy Proceedings Of The 10th Conference On Problems In Theoretical Nuclear Physics written by Sigfrido Boffi and published by World Scientific. This book was released on 2005-04-22 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the conference held in Cortona, October 6-9, 2004, that was organized as part of the project “Theoretical Physics of Nuclei and Many-Body Systems” involving 17 Italian Universities and sponsored by the Italian Ministery of Research and University. All invited papers on the main subjects of the project as well as all the individual contributions on special topics are included. As such these proceedings review the work performed in the last two years by the participating Italian community of nuclear theorists. In addition, in a panel international perspectives are focussed on the future programmes of the experimental physics community.
Download or read book Electromagnetic Interactions and Hadronic Structure written by Frank Close and published by Cambridge University Press. This book was released on 2009-07-23 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by leading experts in the field, this book provides an authoritative overview on electromagnetic interactions. It describes the main features of the experimental data and the theoretical ideas used in their interpretation, and is an essential reference for graduate students and researchers in particle physics and electromagnetic interactions.
Download or read book Gdh 2002 Proceedings Of The Second International Symposium On The Gerasimov drell hearn Sum Rule And The Spin Structure Of The Nucleon written by Marco Anghinolfi and published by World Scientific. This book was released on 2003-06-13 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the GDH 2002 symposium. It is a review of the most recent results on the nucleon spin structure and related sum rules using real and virtual photons. The latest theoretical developments and the new high precision data from different laboratories are presented and discussed. The book provides a comprehensive picture of the nucleon spin studies from the perturbative domain down to the resonance and low momentum transfer region.
Download or read book Proceedings of the First Workshop on Quark Hadron Duality and Transition to PQCD written by Alessandra Fantoni and published by World Scientific. This book was released on 2006 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: While perturbative QCD methods fully describe experimental results at high energies, and chiral perturbation theory is the low energy effective theory of the strong interactions, a form of duality is observed connecting these two regimes. In these intermediate kinematics, a wide variety of reactions are observed which can be described simultaneously by single particle (quark) scattering, and by exclusive resonance (hadron) scattering. The contributions in this proceedings volume discuss recent and existing results, and aim to foster current and future research, investigating the phenomenon of quark-hadron duality. This unique volume contains research work by scientists from different arenas of hadronic physics, dealing with different manifestations of quark-hadron duality. Sample Chapter(s). Chapter 1: Introductory Remarks on Duality in Lepton-Hadron Scattering (490 KB). Contents: Introduction and Review: Experimental and Theoretical Status: Duality in the Polarized Structure Functions (H P Blok); Spin Structure of the Nucleon and Aspects of Duality (Z E Meziani); Duality and Confinement: Quark Models of Duality in Electron and Neutrino Scattering (W Melnitchouk); Hadron Structure on the Back of an Envelope (A W Thomas et al.); Spin-Flavor Decomposition and in Polarized Semi-Inclusive Deep Inelastic Scattering Experiments at Jefferson Lab (X Jiang); Duality in Photoproduction: Duality in Vector-Meson Production (A Donnachie); Onset of Scaling in Exclusive Processes (M Mirazita); Duality in Nuclei: A Partonic Picture of Jet Fragmentation in Nuclei (X-N Wang); Quark Gluon Plasma and Hadronic Gas on the Lattice (M P Lombardo); Duality in Neutrino Experiments: Neutrinos and Local Duality (F Steffens & K Tsushima); Duality and QCD: Higher Twist Effects in Polarized DIS (E Leader et al.); Highly Excited Hadrons in QCD and Beyond (M Shifman); Future Perspectives: Transverse Polarization and Quark-Hadron Duality (O V Teryaev); Research Perspectives with the Jefferson Lab (K de Jager); Perspectives with PANDA (P Gianotti); Summary Talk (P Hoyer); and other papers. Readership: Researchers, academics and lecturers in high energy, particle and nuclear physics.
Download or read book Quark hadron Duality And The Transition To Pqcd Proceedings Of The First Workshop written by Simonetta Liuti and published by World Scientific. This book was released on 2006-02-06 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: While perturbative QCD methods fully describe experimental results at high energies, and chiral perturbation theory is the low energy effective theory of the strong interactions, a form of duality is observed connecting these two regimes. In these intermediate kinematics, a wide variety of reactions are observed which can be described simultaneously by single particle (quark) scattering, and by exclusive resonance (hadron) scattering.The contributions in this proceedings volume discuss recent and existing results, and aim to foster current and future research, investigating the phenomenon of quark-hadron duality.This unique volume contains research work by scientists from different arenas of hadronic physics, dealing with different manifestations of quark-hadron duality.
Download or read book Measurements of the Neutron Longitudinal Spin Asymmetry A1 and Flavor Decomposition in the Valence Quark Region written by David Flay and published by . This book was released on 2014 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current data for the nucleon-virtual photon longitudinal spin asymmetry A1 on the proton and neutron have shown that the ratio of the polarized-to-unpolarized down-quark parton distribution functions, d/d, tends towards -1/2 at large x, in disagreement with the perturbative QCD prediction that d/d approaches 1 but more in line with constituent quark models. As a part of experiment E06-014 in Hall A of Jefferson Lab, double-spin asymmetries were measured in the scattering of a longitudinally polarized electron beam of energies 4.74 and 5.89 GeV from a longitudinally and transversely polarized 3He target in the deep inelastic scattering and resonance region, allowing for the extraction of the neutron asymmetry A1n and the ratios d/d and u/u. We will discuss our analysis of the data and present results for A1 and g1/F1 on both 3He and the neutron, and the resulting quark ratios for the up and down quarks in the kinematic range of 0.2 2 2 for our deep inelastic scattering data. Invoking duality, we also extract A1n and g1n/F1n in the resonance region, characterized by 0.6 2 2. Our measurements are compared to the world data and various theoretical models and more recent predictions using the Dyson-Schwinger Equation approach. We also present analysis of the unpolarized cross section data, which contributes to the g1 spin structure function and eventually the a2 matrix element, an x2-weighted moment of g1. The extracted a2 data are compared to a Lattice QCD calculation.
Download or read book GDH 2002 written by Marco Anghinolfi and published by World Scientific. This book was released on 2003 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the GDH 2002 symposium. It is a review of the most recent results on the nucleon spin structure and related sum rules using real and virtual photons. The latest theoretical developments and the new high precision data from different laboratories are presented and discussed. The book provides a comprehensive picture of the nucleon spin studies from the perturbative domain down to the resonance and low momentum transfer region.
Download or read book Evidence for Quark hadron Duality in Gamma p Helicity Cross Sections written by and published by . This book was released on 2011 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combining data on unpolarized and polarized inclusive proton structure functions, we perform the first detailed study of quark-hadron duality in individual helicity-1/2 and 3/2 virtual photoproduction cross sections. We find that duality is realized more clearly in the helicity-1/2 channel, with duality violating corrections
Download or read book Meson 2002 Proceedings Of The 7th International Workshop On Production Properties And Interaction Of Mesons written by Carlo Guaraldo and published by World Scientific. This book was released on 2003-01-15 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume deals with both the experimental and theoretical aspects of meson physics; in particular, it presents new results. The main topics are: hadronic and electromagnetic meson production in various reactions; meson interaction with mesons, nucleons and nuclei; the structure of hadrons; mesons and fundamental symmetries; exotic systems. The book provides an overview of the current status of these areas, as well as of new developments, besides giving a preview of the forthcoming investigations.
Download or read book Nucleon Structure at Large Bjorken X written by Claude Bourrely and published by American Institute of Physics. This book was released on 2005-03-03 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: Marseille, France, 26-28 July 2004
Download or read book Quark Hadron Duality in Spin Structure Functions g 1 p and g 1 d written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: New measurements of the spin structure functions of the proton and deuteron g1{sup p}(x, Q2) and g1{sup d}(x, Q2) in the nucleon resonance region are compared with extrapolations of target-mass-corrected next-to-leading-order (NLO) QCD fits to higher energy data. Averaged over the entire resonance region (W 2 GeV), the data and QCD fits are in good agreement in both magnitude and Q2 dependence for Q2 1.7 GeV2/c2. This ''global'' duality appears to result from cancellations among the prominent ''local'' resonance regions: in particular strong [sigma]{sub 3/2} contributions in the [Delta](1232) region appear to be compensated by strong [sigma]{sub 1/2} contributions in the resonance region centered on 1.5 GeV. These results are encouraging for the extension of NLO QCD fits to lower W and Q2 than have been used previously.
Download or read book Measurement of the 3He Spin Structure Functions in the Resonance Region written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the biggest challenges in the study of the nucleon structure is the understanding of the transition from partonic degrees of freedom to hadronic degrees of freedom. In 1970, Bloom and Gilman noticed that structure function data taken at SLAC in the resonance region average to the scaling curve of deep inelastic scattering (DIS). Early theoretical interpretations suggested that these two very different regimes can be linked under the condition that the quark-gluon and quark-quark interactions are suppressed. Substantial efforts are ongoing to investigate this phenomenon both experimentally and theoretically. Quark-hadron duality has been confirmed for the unpolarized structure function F2 of the proton and the deuteron using data from the experimental Hall C at Jefferson Lab (JLab). Indications of duality have been seen for the proton polarized structure function g1 and the virtual photon asymmetry A1 at JLab Hall B and HERMES. Because of the different resonance behavior, it is expected that the onset of duality for the neutron will happen at lower momentum transfer than for the proton. Now that precise spin structure data in the DIS region are available at large x, data in the resonance region are greatly needed in order to test duality in spin-dependent structure functions. The goal of experiment E01-012 was to provide such data on the neutron (3He) in the moderate momentum transfer (Q2) region, 1.0
Download or read book Quark Hadron Duality in Neutron Spin Structure and G 2 Moments at Intermediate Q 2 written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Jefferson Lab experiment E01-012 measured the He-3 spin-structure functions and virtual photon asymmetries in the resonance region in the momentum transfer range 1.0
Download or read book Quark Hadron Duality in Neutron 3He Spin Structure written by and published by . This book was released on 2008 with total page 182502 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present experimental results of the first high-precision test of quark-hadron duality in the spin-structure function g_1 of the neutron and $^3$He using a polarized 3He target in the four-momentum-transfer-squared range from 0.7 to 4.0 (GeV/c)^2. Global duality is observed for the spin-structure function g_1 down to at least Q^2 = 1.8 (GeV/c)^2 in both targets. We have also formed the photon-nucleon asymmetry A_1 in the resonance region for 3He and found no strong Q^2-dependence above 2.2 (GeV/c)^2.
