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Related papers: Polarized Nucleon Structure Functions within a Chi…

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We present a quark-parton model to describe polarized and unpolarized nucleon structure functions. The twist-two matrix elements for the QCD evolution analysis of lepton-hadron scattering are calculated within a light-front covariant quark…

High Energy Physics - Phenomenology · Physics 2011-04-15 Marco Traini , Pietro Faccioli , Vicente Vento

We calculate the spin-polarizabilities of the nucleon by means of dispersion relation, where the pion photoproduction amplitude predicted by chiral soliton model is utilized. We consider the $N\pi$ and $\Delta\pi$ channels in the…

Nuclear Theory · Physics 2009-10-31 Y. Tanushi , S. Saito , M. Uehara

The strong interaction is not well understood at low energy, or for interactions with low momentum transfer $Q^2$, but one of the clearest insights we have comes from Chiral Perturbation Theory ($\chi$PT). This effective treatment gives…

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

Nucleon resonance contributions to the polarized proton $g_1$ and $g_2$ structure functions are computed from resonance electroexcitation amplitudes extracted from CLAS exclusive meson electroproduction data. Including resonances in the…

High Energy Physics - Phenomenology · Physics 2023-03-21 A. N. Hiller Blin , V. I. Mokeev , W. Melnitchouk

We present a consistent calculation of the structure functions within a light-front constituent quark model of the nucleon. Relativistic effects and the relevance of the covariance constraints are analyzed for both polarized and unpolarized…

High Energy Physics - Phenomenology · Physics 2009-10-31 P. Faccioli , M. Traini , V. Vento

Phenomenological parameterizations of proton and neutron polarized structure functions, g1p and g1n, are developed for x > 0.02 using deep inelastic data up to ~ 50 (GeV/c)**2 as well as available experimental results on photo- and…

Nuclear Theory · Physics 2017-08-23 S. Simula , M. Osipenko , G. Ricco , M. Taiuti

Polarized parton distributions and structure functions of the nucleon are analyzed in the improved valon model. The valon representation provides a model to represent hadrons in terms of quarks, providing a unified description of bound…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ali N. Khorramian , A. Mirjalili , S. Atashbar Tehrani

The self-consistent chiral soliton of the Nambu--Jona-Lasinio model including the $\omega,\rho$ and $a_1$ (axial-) vector meson fields besides the chiral angle is investigated. The resulting energy spectrum of the one particle Dirac…

High Energy Physics - Phenomenology · Physics 2008-11-26 U. Zückert , R. Alkofer , H. Reinhardt , H. Weigel

We examine the polarized doubly-virtual Compton scattering (VVCS) off the nucleon using chiral perturbation theory ($\chi$PT). The polarized VVCS contains a wealth of information on the spin structure of the nucleon which is relevant to the…

High Energy Physics - Phenomenology · Physics 2021-03-30 Jose Manuel Alarcón , Franziska Hagelstein , Vadim Lensky , Vladimir Pascalutsa

Within the framework of the so-called "valon" model, we argue that a substantial part of the nucleon spin, about 40%, is carried by the polarized valence quarks. The remaining is the result of cancellations between gluon polarization and…

High Energy Physics - Phenomenology · Physics 2008-11-26 Firooz Arash , Fatemeh Taghavi-Shahri

The charge pion polarizability is calculated in the Nambu-Jona-Lasinio model, where the quark loops (in the mean field approximation) and the meson loops (in the $1/N_c$ approximation) are taken into account. We show that quark loop…

High Energy Physics - Phenomenology · Physics 2013-05-29 Yu. M. Bystritskiy , A. V. Guskov , V. N. Pervushin , M. K. Volkov

We give a brief sketch of lattice structure function calculations and review previous results for the axial coupling $g_A$. We outline a new technique for treating fermions on the lattice that preserves chiral symmetry, domain wall…

High Energy Physics - Lattice · Physics 2007-05-23 T. Blum , S. Sasaki

The theoretical predictions of the chiral quark soliton model for the unpolarized and longitudinally polarized structure functions of the nucleon are compared with recent high energy data. The theory is shown to explain all the…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Wakamatsu

We present an update of a phenomenological model for the spin dependent structure functions $g_1(x,Q^2)$ of the proton and neutron. This model is based on a broken SU(6) wavefunction parametrized by the unpolarized structure functions. The…

High Energy Physics - Phenomenology · Physics 2009-10-28 B. Ehrnsperger , A. Schäfer

Recent progress in the field of spin physics of high energy particle interactions is reviewed with particular emphasis on the spin structure functions as measured in polarized deep inelastic lepton-nucleon scattering (DIS). New measurements…

High Energy Physics - Experiment · Physics 2011-07-19 Uta Stosslein

The electron structure functions are studied in polarized $e^+e^-$ scattering. The formulae for longitudinally and transversely polarized electrons are presented. The smallnes of the electron mass leads to negligible cross-sections and…

High Energy Physics - Phenomenology · Physics 2011-07-19 Wojciech Slominski , Jerzy Szwed

We calculate the axial form factor in the chiral quark soliton (semibosonized Nambu - Jona-Lasinio) model using the semiclassical quantization scheme in the next to leading order in angular velocity. The obtained axial form factor is in a…

High Energy Physics - Phenomenology · Physics 2008-02-03 T. Watabe , Chr. V. Christov , K. Goeke

The alternative to the standard formulation of the quark-parton model is proposed. Our relativistically covariant approach is based on the solution of the master equations relating the structure and distribution functions, which…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Zavada

Starting from Martin, Roberts and Stirling fit for unpolarized deep inelastic structure functions and using the newest experimental data on spin asymmetries we get a fit which provides polarized quark distributions. We analyze the behaviour…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Bartelski , S. Tatur