Download or read book Confirmation of Quark hadron Duality in the Neutron F 2 Structure Function written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Using a recently developed technique we extract the neutron F_2^n structure function from new inclusive proton and deuteron data in the large-x region, and test the validity of quark-hadron duality in the neutron. We establish for the first time the accuracy of duality in the low-lying neutron resonance regions over a range of Q^2, and compare with the corresponding results on the proton. Our findings open the possibility of using averaged resonance region data to constrain parton distributions at large x.
Download or read book Quark hadron Duality in the Free Neutron F2 Structure Function written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Thomas Jefferson National Accelerator Facility (JLab) experiment BONuS used a novel spectator-tagging technique to measure the inclusive electron-free neutron scattering cross section and extract the F2 structure function. This data was used to reconstruct moments of F2 in the three prominent resonance region and the moments integrated over the entire resonance region. Comparisons of the experimental results with moments obtained from global parton distribution function parametrization seem to suggest that the quark-hadron duality hypothesis holds locally for the neutron in the second and third resonance regions down to Q2 of 1 GeV2; with up to 20% violations observed in the first resonance region.
Download or read book Direct Observation of Quark Hadron Duality in the Free Neutron ital F sub 2 Structure Function written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Using the recently published data from the BONuS(Barely Off-shell Nucleon Structure) experiment at Jefferson Lab, which utilized a spectator tagging technique to extract the inclusive electron-free neutron scattering cross section, we obtain the first direct observation of quark-hadron duality in the neutron F-2 structure function. The data are used to reconstruct the lowest few (N = 2, 4, and 6) moments of F-2 in the three prominent nucleon resonance regions, as well as the moments integrated over the entire resonance region. Comparison with moments computed from global parametrizations of parton distribution functions suggest that quark-hadron duality holds locally for the neutron in the second and third resonance regions down to Q(2) approximate to 1 GeV2, with violations possibly up to 20% observed in the first resonance region.
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 Applications of Quark hadron Duality in F2 Structure Function written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Inclusive electron-proton and electron-deuteron inelastic cross sections have been measured at Jefferson Lab (JLab) in the resonance region, at large Bjorken x, up to 0.92, and four-momentum transfer squared Q2 up to 7.5 GeV2 in the experiment E00-116. These measurements are used to extend to larger x and Q2 precision, quantitative, studies of the phenomenon of quark-hadron duality. Our analysis confirms, both globally and locally, the apparent violation of quark-hadron duality previously observed at a Q2 of 3.5 GeV2 when resonance data are compared to structure function data created from CTEQ6M and MRST2004 parton distribution functions (PDFs). More importantly, our new data show that this discrepancy saturates by Q2 ~ 4 Gev2, becoming Q2 independent. This suggests only small violations of Q2 evolution by contributions from the higher-twist terms in the resonance region which is confirmed by our comparisons to ALEKHIN and ALLM97. We conclude that the unconstrained strength of the CTEQ6M and MRST2004 PDFs at large x is the major source of the disagreement between data and these parameterizations in the kinematic regime we study and that, in view of quark-hadron duality, properly averaged resonance region data could be used in global QCD fits to reduce PDF uncertainties at large x.
Download or read book Quark Hadron Duality Recent Jefferson Lab Results written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The duality between the partonic and hadronic descriptions of electron--nucleon scattering is a remarkable feature of nuclear interactions. When averaged over appropriate energy intervals the cross section at low energy which is dominated by nucleon resonances resembles the smooth behavior expected from perturbative QCD. Recent Jefferson Lab results indicate that quark-hadron duality is present in a variety of observables, not just the proton F2 structure function. An overview of recent results, especially local quark-hadron duality on the neutron, are presented here.
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 214 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 Qsup2/sup 4.0 (GeV/csup2/sup), where duality is expected to hold. The experiment ran successfully in early 2003 at Jefferson Lab in Hall B. It was an inclusive measurement of longitudinally polarized electrons scattering from a longitudinally or transversely polarized sup3/supHe target. Asymmetries and cross section differences were measured in order to extract the sup3/supHe spin structure function gsub1/sub and virtual photon asymmetry Asub1/sub in the resonance region. A test of quark-hadron duality has then been performed for the sup3/supHe and neutron structure functions. The study of spin duality for the neutron will provide a better understanding of the mechanism of the strong interaction. Moreover, if duality is well understood, our resonance data will bring information on the high x region where theoretical predictions for A
Download or read book Direct Observation of Quark hadron Duality in the Free Neutron math msub mi F mi mn 2 mn msub math Structure Function written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Using data from the recent BONuS experiment at Jefferson Lab, which utilized a novel spectator tagging technique to extract the inclusive electron-free neutron scattering cross section, we obtain the first direct observation of quark-hadron duality in the neutron F2 structure function. In addition, the data are used to reconstruct the lowest few (N = 2, 4 and 6) moments of F2 in the three prominent nucleon resonance regions, as well as the moments integrated over the entire resonance region. Comparison with moments computed from global parametrizations of parton distribution functions suggest that quark--hadron duality holds locally for the neutron in the second and third resonance regions down to Q2 ≈ 1 GeV2, with violations possibly up to 20% observed in the first resonance region.
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.
Download or read book Neutron Spin Structure in the Resonance Region and Quark Hadron Duality written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Quark-Hadron duality has been experimentally demonstrated for the spin independent structure function F2. Duality is observed when, at the same value of scaling variable x{sub bj}, the smooth scaling curve at high momentum transfer becomes an average over the resonances at lower momentum transfer. Jefferson Lab experiment 01-012 used the polarized 3He target in Hall A for an extraction of the neutron spin structure function g1(superscript n) and the virtual photon asymmetry A1(superscript n) in the resonance region over a Q2 range from 1.0 to 4.0 (GeV/c)2. Data from E01-012 combined with Deep Inelastic Scattering data will provide a test of quark-hadron duality predictions for g1(superscript n) and A1(superscript n). This will be one of the first tests of the spin and flavor dependence of quark-hadron duality. The demonstration of duality for spin structure functions will enable us to use the resonance data to study the nucleon spin structure in the large x{sub bj} region.
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 Local Duality Predictions for X H 1 Structure Functions written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent data on the proton F2 structure function in the resonance region suggest that local quark-hadron duality works remarkably well for each of the low-lying resonances, including the elastic, to rather low values of Q2. The authors discuss model-independent relations between structure functions x≈1 and elastic electromagnetic form factors. The x→1 behavior of the nucleon polarization asymmetries and the neutron to proton structure function ratios is studied as a function of Q-squared using available data on the electric and magnetic form factors.
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 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. Contents: Introduction and Review: Experimental and Theoretical Status: Duality in the Polarized Structure Functions (H 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 Thomas); Spin-Flavor Decomposition and Duality in Polarized SIDIS (X Jiang); Hadron Structure on the Back of an Envelope (A Thomas); Duality in Photoproduction: Duality in Vector Meson Production (A Donnachie); Onsef 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: Local Duality and Charge Symmetry Violation (F Steffens); Duality and QCD: Higher Twist Effects in Polarized DIS (D Stamenov); Quark-Hadron Duality and High Excitations (M Shifman); Highly Excited Hadrons in QCD and Beyond (M Shifman); Future Perspectives: Transverse Polarization and Quark-Hadron Duality (O Teryaev); Research Perspectives with the Jefferson Lab (K de Jager); Perspectives with PANDA (P Gianotti); Summary Talk (P Hoyer); Transverse Polarization and Quark Gluon Duality (O Teryaev); 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 Quark hadron Duality in Structure Functions written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We review recent progress in the study of quark-hadron duality in electron-nucleon structure functions. New developments include insights into the local aspects of duality obtained using truncated moments of structure functions, which allow duality-violating higher-twist contributions to be identified in individual resonance regions. Preliminary studies of pion electropro-duction have also showed the first glimpses of duality in semi-inclusive cross sections, which if confirmed would greatly expand the scope of constraining the flavor and spin dependence of parton distributions.
Download or read book Quark Hadron Duality and Nucleon Valence Structure n written by and published by . This book was released on 1999 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: A newly-obtained data sample of inclusive electron-nucleon scattering from deuterium and hydrogen targets at Jefferson Lab has been analyzed for precision tests of quark-hadron duality. In all cases, duality appears to be a non-trivial dynamic property of the nucleon structure function. Assuming duality, the proton magnetic form factor is extracted from the inelastic data alone, and found to be in good agreement with the world's data. Higher twist contributions are found to be small on average, even down to Q^2 ~ 0 5 GeV^2. The investigation yields a scaling curve from duality arguments which resembles deep-inelastic neutrino-nucleus scattering data, indicating a potential sensitivity to valence and valence-like structure.
