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Related papers: The pion-cloud contribution to the electromagnetic…

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We investigate the effect of different relativistic spin couplings of constituent quarks on nucleon electroweak properties. Within each quark spin coupling scheme the correlations between static electroweak observables are found to be…

Nuclear Theory · Physics 2011-07-19 E. F. Suisso , W. R. B. de Araujo , T. Frederico , M. Beyer , H. J. Weber

We summarize recent results for the spectrum and properties of light pseudoscalar and scalar hadrons in a functional approach to QCD using Dyson-Schwinger and Bethe-Salpeter equations. We focus in particular on the role of pions as virtual…

High Energy Physics - Phenomenology · Physics 2013-05-17 Walter Heupel , Stanislav Kubrak , Gernot Eichmann , Christian S. Fischer

Results for the proton and neutron electric and magnetic form factors as well as the nucleon axial form factor are presented for constituent quark models, based on either one-gluon-exchange and Goldstone-boson-exchange dynamics. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. F. Wagenbrunn , S. Boffi , L. Ya. Glozman , W. Klink , W. Plessas , M. Radici

The application of relativistic constituent quark models to the evaluation of the electromagnetic properties of the nucleon and its resonances is addressed. The role of the pair creation process in the Feynmann triangle diagram is discussed…

Nuclear Theory · Physics 2017-08-23 Silvano Simula

In this work, we employ a dispersion relation that allows to recover the electromagnetic form factor of the pion from its modulus along the unitarity cut. Unlike the standard dispersive approach, this method extends in a straightforward…

High Energy Physics - Phenomenology · Physics 2024-10-24 Pablo Sanchez-Puertas , Enrique Ruiz Arriola

We apply the perturbative chiral quark model at one loop to analyze the electromagnetic form factors of the baryon octet. The analytic expressions for baryon form factors, which are given in terms of fundamental parameters of low-energy…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Cheedket , V. E. Lyubovitskij , Th. Gutsche , Amand Faessler , K. Pumsa-ard , Y. Yan

The parton content of the nucleon is explored within a meson-cloud model developed to derive light-cone wave functions for the physical nucleon. The model is here applied to study electromagnetic form factors, distribution amplitudes and…

High Energy Physics - Phenomenology · Physics 2010-01-26 S. Boffi , B. Pasquini

We perform a calculation of the relativistic corrections to the electromagnetic elastic form factors of the nucleon obtained with various Constituent Quark Models. With respect to the non relativistic calculations a substantial improvement…

Nuclear Theory · Physics 2015-06-26 M. De Sanctis , E. Santopinto , M. M. Giannini

A symmetry-preserving analysis of strong interaction quantum field equations is used to complete a unified treatment of pion, kaon, nucleon electromagnetic and gravitational form factors. Findings include a demonstration that the pion…

High Energy Physics - Phenomenology · Physics 2024-10-10 Z. -Q. Yao , Y. -Z. Xu , D. Binosi , Z. -F. Cui , M. Ding , K. Raya , C. D. Roberts , J. Rodríguez-Quintero , S. M. Schmidt

The spatial distribution of charge and magnetization within the nucleon (proton and neutron) is encoded in the elastic electromagnetic form factors $G_E^{(p,n)}$ and $G_M^{(p,n)}$. These form factors have been precisely measured utilizing…

Nuclear Theory · Physics 2017-08-02 I. A. Qattan , J. Arrington

The number of pions in the nucleon is a theoretical concept and its value is model dependent. It is, however, a useful tool to understand the pionic contribution to several nucleon observables such as electric charge radii, magnetic…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Fiolhais , B. Golli , M. Rosina , S. Sirca

We derive the electric and magnetic form factors of the neutron in the framework of a relativistic constituent quark model. Our parameter free prediction agrees well with a recent, accurate measurement. The relativistic features of the…

High Energy Physics - Phenomenology · Physics 2015-06-25 Felix Schlumpf

We compute the electromagnetic form factor of a "pion" with mass m_pi=330MeV at low values of Q^2\equiv -q^2, where q is the momentum transfer. The computations are performed in a lattice simulation using an ensemble of the RBC/UKQCD…

High Energy Physics - Lattice · Physics 2009-01-06 P. A. Boyle , J. M. Flynn , A. Juttner , C. Kelly , H. Pedroso de Lima , C. M. Maynard , C. T. Sachrajda , J. M. Zanotti

For the first time, a phenomenological analysis of the experimental electromagnetic form factors of the nucleon, both in the timelike and spacelike regions, is performed by taking into account the effects of nonvalence components in the…

High Energy Physics - Phenomenology · Physics 2009-02-16 J. P. B. C. de Melo , T. Frederico , E. Pace , S. Pisano , G. Salmè

The three-dimensional spatial structure of hadrons is encoded in their form factors. Via appropriate Fourier transform, the latter describe how charge, energy, linear and angular momentum, but also pressure are distributed inside these…

High Energy Physics - Phenomenology · Physics 2024-07-16 Cédric Lorcé

In the framework of chiral effective field theory of delta resonances, nucleons and pions interacting with background gravitational field we calculate the gravitational form factors of the nucleon up to fourth order in the small scale…

High Energy Physics - Phenomenology · Physics 2024-01-25 H. Alharazin

The role of 5-quark components in the pion and electromagnetic decays and transition form factors of the N(1440) is explored. The $qqqq\bar q$ components, where the 4-quark subsystem has the flavor-spin symmetries $[4]_{FS}[22]_F[22]_S$ and…

Nuclear Theory · Physics 2008-11-26 Q. B. Li , D. O. Riska

A simple model of a composite nucleon is developed in which a fermion and a boson, representing quark and diquark constituents of the nucleon, form a bound state owing to a contact interaction. Photon and pion couplings to the quark provide…

Nuclear Theory · Physics 2008-11-26 J. A. Tjon , S. J. Wallace

We present detailed numerical results for the pion space-like electromagnetic form factor obtained within a recently proposed model of the pion electromagnetic current in a confining light-front QCD-inspired model. The model incorporates…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. P. B. C. de Melo , T. Frederico , E. Pace , G. Salme

The covariant spectator formalism is used to model the nucleon and the $\Delta$(1232) as a system of three constituent quarks with their own electromagnetic structure. The definition of the ``fixed-axis'' polarization states for the diquark…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Ramalho , M. T. Pena , Franz Gross