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Related papers: Nucleon form factors and structure functions

200 papers

Nucleon form factors are calculated on q^2 in [0,3] GeV^2 using an Ansatz for the nucleon's Fadde'ev amplitude motivated by quark-diquark solutions of the relativistic Fadde'ev equation. Only the scalar diquark is retained, and it and the…

Nuclear Theory · Physics 2009-01-14 J. C. R. Bloch , C. D. Roberts , S. M. Schmidt , A. Bender , M. R. Frank

Modifications of baryon properties due to the restoration of the chiral symmetry in an external hot and dense baryon medium are investigated in an effective chiral quark-meson theory. The nucleon arises as a soliton of the Gell-Mann -…

High Energy Physics - Phenomenology · Physics 2009-10-22 Chr. V. Christov , E. Ruiz Arriola , K. Goeke

We calculate the electromagnetic, axial and pseudo-scalar form factors of the Nucleon to $\Delta(1232)$ transition using two dynamical light degenerate quarks and a dynamical strange quark simulated with the domain wall fermion action.…

High Energy Physics - Lattice · Physics 2011-02-25 C. Alexandrou , G. Koutsou , J. W. Negele , Y. Proestos , A. Tsapalis

Recent experimental data on space- and time-like form factors of the nucleon are analyzed in terms of a two-component model with a quark-like intrinsics structure and a meson cloud. A good overall agreement is found for all electromagnetic…

Nuclear Theory · Physics 2017-11-02 R. Bijker

The nucleon form factors provide fundamental knowledge about the strong interaction. We review the flavor composition of the nucleon form factors and focus on an analysis of the possible impact of the s-quark contribution. A future…

Nuclear Experiment · Physics 2020-01-08 Bogdan Wojtsekhowski

Dispersion relations allow for a coherent description of the nucleon electromagnetic form factors measured over a large range of momentum transfer, $Q^2 \simeq 0 \ldots 35$ GeV$^2$. Including constraints from unitarity and perturbative QCD,…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Mergell , Ulf-G. Meißner , D. Drechsel

We consider the axial-vector together with its induced pseudo-scalar form factor of the nucleon as computed from the chiral Lagrangian with nucleon and isobar degrees of freedom. The form factors are evaluated at the one-loop level, where…

High Energy Physics - Phenomenology · Physics 2024-04-05 Felix Hermsen , Tobias Isken , David Thoma , Matthias F. M. Lutz

We analyse various $U(1)_{EM}$ form factors of mesons at strong coupling in an $\mathcal{N}=2$ flavored version of $\mathcal{N}=4$ $SYM$ which becomes conformal in the UV. The quark mass breaks the conformal symmetry in the IR and generates…

High Energy Physics - Theory · Physics 2008-11-26 D. Rodriguez-Gomez , J. Ward

We present the N_f=2+1 clover fermion lattice QCD calculation of the nucleon strangeness form factors. We evaluate disconnected insertions using the Z(4) stochastic method, along with unbiased subtractions from the hopping parameter…

High Energy Physics - Phenomenology · Physics 2010-09-22 Takumi Doi , Mridupawan Deka , Shao-Jing Dong , Terrence Draper , Keh-Fei Liu , Devdatta Mankame , Nilmani Mathur , Thomas Streuer

We address the issue of a consistent power counting scheme in manifestly Lorentz-invariant baryon chiral perturbation theory. We discuss the inclusion of vector mesons in the calculation of the nucleon electromagnetic form factors. We…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Scherer

We report on an analysis of the average quark momentum fraction of the nucleon and related quantities using $N_\mathrm{f}=2+1$ Wilson fermions. Computations are performed on four CLS ensembles covering three values of the lattice spacing at…

High Energy Physics - Lattice · Physics 2018-04-18 Konstantin Ottnad , Tim Harris , Harvey Meyer , Georg von Hippel , Jonas Wilhelm , Hartmut Wittig

We investigate the multipole structure of the nucleon tensor form factors within the chiral quark-soliton model based on the $1/N_c$ expansion. Extending the previous leading-order analysis~\cite{Ghim:2025gqo}, we include the rotational…

High Energy Physics - Phenomenology · Physics 2026-05-26 Nam-Yong Ghim , Ho-Yeon Won , June-Young Kim , Hyun-Chul Kim

We present a high statistics study of the pion and nucleon light and strange quark sigma terms using $N_f=2$ dynamical non-perturbatively improved clover fermions with a range of pion masses down to $m_\pi\sim 150$ MeV and several volumes,…

High Energy Physics - Lattice · Physics 2016-08-06 Gunnar S. Bali , Sara Collins , Daniel Richtmann , Andreas Schäfer , Wolfgang Söldner , André Sternbeck

We study the nucleon electromagnetic form factors (EM FFs) using a recently developed method combining Chiral Effective Field Theory ($\chi$EFT) and dispersion analysis. The spectral functions on the two-pion cut at $t > 4 M_\pi^2$ are…

High Energy Physics - Phenomenology · Physics 2018-05-16 J. M. Alarcón , C. Weiss

We calculate the strange quark content of the nucleon in 2+1-flavor lattice QCD. Chirally symmetric overlap fermion formulation is used to avoid the contamination from up and down quark contents due to an operator mixing between strange and…

High Energy Physics - Lattice · Physics 2015-03-20 JLQCD Collaboration , H. Ohki , K. Takeda , S. Aoki , S. Hashimoto , T. Kaneko , H. Matsufuru , J. Noaki , T. Onogi

We present lattice QCD calculations of nucleon electromagnetic form factors using pion masses $m_\pi$ = 149, 202, and 254 MeV and an action with clover-improved Wilson quarks coupled to smeared gauge fields, as used by the…

High Energy Physics - Lattice · Physics 2014-11-20 J. R. Green , J. W. Negele , A. V. Pochinsky , S. N. Syritsyn , M. Engelhardt , S. Krieg

The relativistic version of finite-range-regularisation is proposed. The covariant regulator is generated from the nonlocal Lagrangian. This nonlocal interaction is gauge invariant and is applied to study the nucleon electromagnetic form…

Nuclear Theory · Physics 2018-02-21 Fangcheng He , P. Wang

The strangeness content of nucleon form factors is analyzed in a two-component model with a quark-like intrinsic structure surrounded by a meson cloud. A comparison with the available experimental data from the SAMPLE, PVA4, HAPPEX and G0…

Nuclear Theory · Physics 2008-11-26 R. Bijker

We present a study of the pseudoscalar and vector meson form factors, calculated using the Fat-Link Irrelevant Clover (FLIC) action in the framework of Quenched Lattice QCD. Of particular interest is the determination of a negative…

High Energy Physics - Lattice · Physics 2008-11-26 J. N. Hedditch , W. Kamleh , B. G. Lasscock , D. B. Leinweber , A. G. Williams , J. M. Zanotti

In-medium nucleon electromagnetic form factors are calculated in the quark meson coupling model. The form factors are typically found to be suppressed as the density increases. For example, at normal nuclear density and $Q^2 \sim 0.3 {…

Nuclear Theory · Physics 2008-11-26 D. H. Lu , A. W. Thomas , K. Tsushima , A. G. Williams , K. Saito