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Related papers: Polarized EMC Effect in the QMC Model

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We determine nuclear structure functions and quark distributions for $^7$Li, $^{11}$B, $^{15}$N and $^{27}$Al. For the nucleon bound state we solve the covariant quark-diquark equations in a confining Nambu--Jona-Lasinio model, which yields…

Nuclear Theory · Physics 2010-02-17 I. C. Cloet , W. Bentz , A. W. Thomas

The persistently mysterious deviations from unity of the ratio of nuclear target structure functions to those of deuterium as measured in deep inelastic scattering (often termed the "EMC Effect") have become the canonical observable for…

Nuclear Experiment · Physics 2021-01-20 H. Szumila-Vance , C. Keppel , S. Escalante , N. Kalantarians

We investigate the gluonic structure of nuclei within a mean-field model of nuclear structure based upon the modification of the structure of a bound nucleon, with the nucleon described by the Nambu--Jona-Lasinio model. This approach has…

High Energy Physics - Phenomenology · Physics 2022-02-16 Xuan-Gong Wang , Wolfgang Bentz , Ian C. Cloët , Anthony W. Thomas

Recent data on polarized proton knockout reactions off He-4 nuclei suggest a small but nonzero modification of proton electromagnetic form factors in medium. Using model independent relations derived on the basis of quark-hadron duality, we…

Nuclear Theory · Physics 2008-11-26 W. Melnitchouk , K. Tsushima , A. W. Thomas

We determine the quark distributions and structure functions for both unpolarized and polarized DIS of leptons on nucleons and nuclei. The scalar and vector mean fields in the nucleus modify the motion of the quarks inside the nucleons. By…

Nuclear Theory · Physics 2008-11-26 W. Bentz , I. C. Cloët , T. Ito , A. W. Thomas , K. Yazaki

The EMC effect is studied in the perturbative QCD hard pomeron approach. In the limit $x\rightarrow 0$ and for a nucleus with a constant density the effect is found to be a function of a single variable which combines its $x$-, $Q$- and…

High Energy Physics - Phenomenology · Physics 2016-09-01 N. Armesto , M. A. Braun

A simple statistical model in terms of light-front kinematic variables is used to explain the nuclear EMC effect in the range $x \in [0.2,~0.7]$, which was constructed by us previously to calculate the parton distribution functions (PDFs)…

Nuclear Theory · Physics 2010-11-02 Yunhua Zhang , Lijing Shao , Bo-Qiang Ma

An excellent description of both spin-independent and spin-dependent quark distributions and structure functions has been obtained with a modified Nambu-Jona-Lasinio model, which is free of unphysical thresholds for nucleon decay into…

Nuclear Theory · Physics 2010-02-17 I. C. Cloet , W. Bentz , A. W. Thomas

The modified quark-meson coupling model, which features a density dependent bag constant and bag radius in nuclear matter, is checked against the EMC effect within the framework of dynamical rescaling. Our emphasis is on the change in the…

Nuclear Theory · Physics 2008-11-26 Xuemin Jin , B. K. Jennings

We discuss the electromagnetic form factors, axial form factors, and structure functions of a bound nucleon in the quark-meson coupling (QMC) model. Free space nucleon form factors are calculated using the improved cloudy bag model (ICBM).…

Nuclear Theory · Physics 2007-05-23 K. Tsushima , D. H. Lu , W. Melnitchouk , K. Saito , A. W. Thomas

The light-front formalism for a covariant description of the European Muon Collaboration (EMC) effect, already applied to $^3$He, is formally extended to any nucleus, and used for actually calculating the $^3$H and $^4$He cases. The…

The density dependence of the bag parameters is studied in a framework which links the Quark-Meson Coupling model and the field theory of hadrons for nuclear matter description. The EMC effect is treated in the dynamical rescaling…

Nuclear Theory · Physics 2009-09-25 R. Aguirre , M. Schvellinger

Applying exact QCD sum rules for the baryon charge and energy-momentum we demonstrate that if nucleons are the only degrees of freedom of nuclear wave function, the structure function of a nucleus would be the additive sum of the nucleon…

High Energy Physics - Phenomenology · Physics 2015-06-04 Leonid Frankfurt , Mark Strikman

Mechanisms of spin-flavor SU(6) symmetry breaking in Quantum Chromodynamics (QCD) are studied via an extraction of the free neutron structure function from a global analysis of deep inelastic scattering (DIS) data on the proton and on…

We demonstrate that for small values of momentum transfer, Q^2, the in-medium change of the G_E/G_M form factor ratio for a bound neutron is dominated by the change in the electric charge radius and predict in a model independent manner…

Nuclear Theory · Physics 2009-09-02 I. C. Cloët , Gerald A. Miller , E. Piasetzky , G. Ron

The atomic nucleus is made of protons and neutrons (nucleons), that are themselves composed of quarks and gluons. Understanding how the quark-gluon structure of a nucleon bound in an atomic nucleus is modified by the surrounding nucleons is…

Recent developments in understanding the influence of the nucleus on deep-inelastic structure functions, the EMC effect, are reviewed. A new data base which expresses ratios of structure functions in terms of the Bjorken variable…

Nuclear Theory · Physics 2013-06-20 O. Hen , D. W. Higinbotham , G. A. Miller , E. Piasetzky , L. B. Weinstein

The EMC effect is studied by using the GLR-MQ-ZSR equation with minimum number of free parameters, where the nuclear shadowing effect is a dynamical evolution result of the equation, and nucleon swelling and Fermi motion in the nuclear…

High Energy Physics - Phenomenology · Physics 2014-09-11 Xurong Chen , Jianhong Ruan , Rong Wang , Pengming Zhang , Wei Zhu

It is widely discussed in the literature that the wave function of the nucleon bound in a nucleus is modified due to the interaction with the surrounding medium. We argue that the modification should strongly depend on the momentum of the…

Nuclear Theory · Physics 2008-11-26 C. Ciofi degli Atti , L. L. Frankfurt , L. P. Kaptari , M. I. Strikman

Analyzing global data on the EMC effect, which denotes differences in parton distribution functions in nuclei compared to unbound nucleons, reveals tensions. Precise measurements at Jefferson Lab, studying both x and A dependence, show…

Nuclear Experiment · Physics 2024-02-28 S. Moran , M. Arratia , J. Arrington , D. Gaskell , B. Schmookler
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