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Related papers: Nucleon electromagnetic form factors in two-flavou…

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Results on the electromagnetic form factors of the nucleon using twisted mass fermion configurations are presented. These include a gauge field ensemble simulated with two degenerate light quarks yielding a pion mass of around 130 MeV, as…

Lattice simulations of QCD have produced precise estimates for the masses of the lowest-lying hadrons which show excellent agreement with experiment. By contrast, lattice results for the vector and axial vector form factors of the nucleon…

High Energy Physics - Lattice · Physics 2011-09-23 B. B. Brandt , S. Capitani , M. Della Morte , D. Djukanovic , J. Gegelia , G. von Hippel , A. Juttner , B. Knippschild , H. B. Meyer , H. Wittig

The electromagnetic nucleon to Delta transition form factors are evaluated using two degenerate flavors of dynamical Wilson fermions and using dynamical sea staggered fermions with domain wall valence quarks. The two subdominant quadrupole…

High Energy Physics - Lattice · Physics 2008-11-26 C. Alexandrou , G. Koutsou , H. Neff , J. W. Negele , W. Schroers , A. Tsapalis

We present preliminary results on the axial form factor $G_A(Q^2)$ and the induced pseudoscalar form factor $G_P(Q^2)$ of the nucleon. A systematic analysis of the excited-state contributions to form factors is performed on the CLS ensemble…

High Energy Physics - Lattice · Physics 2014-11-24 P. M. Junnarkar , S. Capitani , D. Djukanovic , G. von Hippel , J. Hua , B. Jäger , H. B. Meyer , T. D. Rae , H. Wittig

The electromagnetic and axial form factors of the nucleon are evaluated in twisted mass QCD with two degenerate flavors of light, dynamical quarks. The axial charge g_A, magnetic moment and the Dirac and Pauli radii are determined for pion…

We calculate the electromagnetic and the axial form factors of the nucleon within the framework of light cone sum rules (LCSR) to leading order in QCD and including higher twist corrections. In particular we motivate a certain choice for…

High Energy Physics - Phenomenology · Physics 2009-11-11 V. M. Braun , A. Lenz , M. Wittmann

In treating the relativistic three-quark problem, a dressed-quark propagator parameterization is used which is compatible with recent lattice data and pion observables. Furthermore two-quark correlations are modeled as a series of quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Oettel , R. Alkofer

The nucleon isovector electromagnetic form factors are calculated up to next-to-next-to-leading order by combining relativistic chiral perturbation theory (ChPT) of pion, nucleon, and $\Delta$(1232) with dispersion theory. We specifically…

High Energy Physics - Phenomenology · Physics 2023-12-18 Fernando Alvarado , Di An , Luis Alvarez-Ruso , Stefan Leupold

The extrapolation of nucleon magnetic form factors calculated within lattice QCD is investigated within a framework based upon heavy baryon chiral effective-field theory. All one-loop graphs are considered at arbitrary momentum transfer and…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Wang , D. B. Leinweber , A. W. Thomas , R. D. Young

In this paper we present the derivation as well as the numerical results for the electromagnetic form factors of the nucleon within the chiral quark soliton model in the semiclassical quantization scheme. The model is based on semibosonized…

High Energy Physics - Phenomenology · Physics 2009-10-28 Chr. V. Christov , A. Z. Górski , K. Goeke , P. V. Pobylitsa

We have performed an evaluation of the individual up- and down-flavor contributions to the nucleon electromagnetic form factors within a relativistic constituent-quark model. It is found that the theoretical parameter-free predictions agree…

High Energy Physics - Phenomenology · Physics 2013-04-24 M. Rohrmoser , K. -S. Choi , W. Plessas

We present a nucleon structure analysis including local isovector charges as well as twist-2 operator insertions. Computations are performed on CLS ensembles with $N_f=2+1$ Wilson fermions, covering four values of the lattice spacing and…

High Energy Physics - Lattice · Physics 2018-11-27 Konstantin Ottnad , Tim Harris , Harvey Meyer , Georg von Hippel , Jonas Wilhelm , Hartmut Wittig

We present results on the electromagnetic and axial nucleon form factors using two degenerate flavors of twisted mass fermions on lattices of spatial size 2.1 fm and 2.7 fm and a lattice spacing of about 0.09 fm. We consider pion masses in…

High Energy Physics - Lattice · Physics 2010-02-05 C. Alexandrou , T. Korzec , G. Koutsou , R. Baron , P. Guichon , M. Brinet , J. Carbonell , P. -A. Harraud , K. Jansen

We present a calculation of pion electromagnetic and scalar form factors in two-flavor QCD with the non-perturbatively O(a)-improved Wilson fermion. Chiral extrapolation of the corresponding charge radius is discussed based on the chiral…

We investigate the electromagnetic form factors of the nucleon within an effective chiral theory derived from the QCD instanton vacuum, taking into account the finite current quark mass. The momentum-dependent dynamical quark mass,…

High Energy Physics - Phenomenology · Physics 2026-05-27 Hui-Jae Lee , Yongwoo Choi , Hyun-Chul Kim

We determine generalized form factors of the nucleon from lattice simulations with $N_f = 2$ mass-degenerate non-perturbatively improved Wilson-Sheikholeslami-Wohlert fermions down to a pion mass of 150 MeV. We also present the resulting…

High Energy Physics - Lattice · Physics 2016-01-20 Gunnar Bali , Sara Collins , Meinulf Göckeler , Rudolf Rödl , Andreas Schäfer , Andre Sternbeck

An expansion of the electromagnetic form factors of the nucleon and Delta(1232) in small momentum transfer and pion mass is performed in a manifestly-covariant EFT framework consistent with chiral symmetry and analyticity. We present the…

High Energy Physics - Phenomenology · Physics 2013-05-30 T. Ledwig , J. Martin-Camalich , V. Pascalutsa , M. Vanderhaeghen

We evaluate the strange nucleon electromagnetic form factors using an ensemble of gauge configurations generated with two degenerate maximally twisted mass clover-improved fermions with mass tuned to approximately reproduce the physical…

High Energy Physics - Lattice · Physics 2018-05-23 C. Alexandrou , M. Constantinou , K. Hadjiyiannakou , K. Jansen , C. Kallidonis , G. Koutsou , A. Vaquero Aviles-Casco

We present a detailed study of the nucleon electromagnetic form factors in the spacelike region by combining three complementary approaches: two GPD-based contributions and a vector-meson exchange component. By fitting experimental data, we…

High Energy Physics - Phenomenology · Physics 2026-04-13 Hossein Vaziri , Mohammad Reza Shojaei , Pere Masjuan

Proton and neutron electric and magnetic form factors are the primary characteristics of their spatial structure and have been studied extensively over the past half-century. At large values of the momentum transfer $Q^2$ they should reveal…

High Energy Physics - Lattice · Physics 2025-02-25 S. Syritsyn , M. Engelhardt , S. Krieg , J. Negele , A. Pochinsky