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Related papers: A quark model analysis of the Sivers function

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Using a quark model, we calculate symmetry breaking effects in the valence quark distributions of the nucleon. In particular, we examine the breaking of the quark model SU(4) symmetry by color magnetic effects, and find that color magnetism…

Nuclear Theory · Physics 2007-05-23 C. J. Benesh , T. Goldman , G. J. Stephenson

We summarise applications of Dyson-Schwinger equations to the theory and phenomenology of hadrons. Some exact results for pseudoscalar mesons are highlighted with details relating to the U_A(1) problem. We describe inferences from the gap…

Nuclear Theory · Physics 2017-08-23 M. S. Bhagwat , I. C. Cloet , C. D. Roberts

We construct a simple two-phase model of the nucleon structure functions valid for both small and large Q^2 and in the broad range of Bjorken x. The model incorporates hadron dominance at small x and Q^2 and parton model at large Q^2. The…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. Szczurek , V. Uleshchenko

We provide a consistent regularization procedure for calculating hadron structure functions in a chiral quark model. The structure functions are extracted from the absorptive part of the forward Compton amplitude in the Bjorken limit. Since…

High Energy Physics - Phenomenology · Physics 2009-10-31 H. Weigel , E. Ruiz Arriola , L. Gamberg

We carry out a systematic investigation of twist-two spin dependent structure functions of the nucleon within the framework of the chiral quark soliton model (CQSM) by paying special attention to the role of chiral symmetry of QCD. The…

High Energy Physics - Phenomenology · Physics 2010-04-06 Masashi Wakamatsu , Takanori Kubota

In this talk I review studies of hadron properties in bosonized chiral quark models for the quark flavor dynamics. Mesons are constructed from Bethe--Salpeter equations and baryons emerge as chiral solitons. Such models require…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. Weigel

The forward limit of the chiral-odd generalized parton distributions (GPDs) and their lower moments are investigated within the framework of the chiral quark soliton model (CQSM), with particular emphasis upon the transversity decomposition…

High Energy Physics - Phenomenology · Physics 2009-02-18 M. Wakamatsu

In light of the forthcoming high precision quasielastic electron scattering data from Jefferson Lab, it is timely for the various approaches to nuclear structure to make robust predictions for the associated response functions. With this in…

Nuclear Theory · Physics 2016-01-27 Ian C. Cloët , Wolfgang Bentz , Anthony W. Thomas

We present a model for the structure of baryons in which the valence partons interact through a linear potential. This model can be derived from QCD in the approximation where transverse momenta are ignored. We compare the valence quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. S. Krishnaswami

The chiral constituent quark model ($\chi$CQM) has been extended to calculate the flavor structure of the nucleon through the meson-nucleon sigma terms which have large contributions from the quark sea and are greatly affected by chiral…

High Energy Physics - Phenomenology · Physics 2015-05-28 Harleen Dahiya , Neetika Sharma

Parton distributions are constructed in a statistical physical picture of the nucleon. The chiral properties of QCD lead to strong relations between quarks and antiquarks distributions and the importance of the Pauli exclusion principle is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jacques Soffer

A previous approach with Fermi-Dirac distributions for fermion partons is here improved to comply with the expected low $x$ behaviour of structure functions. We are so able to get a fair description of the unpolarized and polarized…

High Energy Physics - Phenomenology · Physics 2009-10-28 F. Buccella , G. Miele , G. Migliore , V. Tibullo

Confronted with some surprising claims about experimentally measured or theoretically expected dependencies on the involved momentum transfer of various form factors of pseudoscalar mesons, we reassess the present status of these quantities…

High Energy Physics - Phenomenology · Physics 2012-11-01 Irina Balakireva , Wolfgang Lucha , Dmitri Melikhov

Polarised Semi-Inclusive Deep Inelastic Scattering (SIDIS) processes allow to study Transverse Momentum Dependent partonic distributions (TMDs), which reveal a non trivial three dimensional internal structure of the hadrons in momentum…

High Energy Physics - Phenomenology · Physics 2015-05-20 M. Anselmino , M. Boglione , U. D'Alesio , S. Melis , F. Murgia , A. Prokudin

Recently we have shown that due account of Wigner spin rotations is needed to match the ISGW model consistently onto HQET. We now discuss the flavour dependence of this procedure. We find that for finite mass ``heavy'' quark the universal…

High Energy Physics - Phenomenology · Physics 2010-11-01 F. E. Close , A. Wambach

We present the first calculation in lattice QCD of the lowest two moments of transverse spin densities of quarks in the nucleon. They encode correlations between quark spin and orbital angular momentum. Our dynamical simulations are based…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , Ph. Hägler , R. Horsley , Y. Nakamura , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , H. Stüben , J. M. Zanotti

Embedding QCD into the standard model breaks various symmetries of QCD explicitly, especially C and P. While these effects are usually perturbatively small, they can be amplified in extreme environments like merging neutron stars or by the…

High Energy Physics - Phenomenology · Physics 2017-03-08 Axel Maas , Walid Ahmed Mian

Approximate relations among transverse momentum dependent quark distribution functions are established in the framework of the QCD parton model. The validity of such results survives QCD evolution effects, owing to the Politzer theorem on…

High Energy Physics - Phenomenology · Physics 2011-08-01 Elvio Di Salvo

There exists a large field for phenomenological models in which the knowledge of the structure of hadrons in terms of QCD constituents obtained from deep inelastic scatterings is related to their behaviour in soft processes. One of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Nyiri

The generalized parton distributions, introduced nearly a decade ago, have emerged as a universal tool to describe hadrons in terms of quark and gluonic degrees of freedom. They combine the features of form factors, parton densities and…

High Energy Physics - Phenomenology · Physics 2009-09-29 A. V. Belitsky , A. V. Radyushkin