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Related papers: Nucleon generalized form factors with twisted mass…

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We investigate the gravitational form factors (GFFs) of the nucleon and the baryon octet, decomposed into their flavor components, utilizing a pion mean-field approach grounded in the large $N_c$ limit of Quantum Chromodynamics (QCD). Our…

High Energy Physics - Phenomenology · Physics 2024-04-16 Ho-Yeon Won , Hyun-Chul Kim , June-Young Kim

A covariant quark model, based both on the spectator formalism and on vector meson dominance, and previously calibrated by the physical data, is here extended to the unphysical region of the lattice data by means of one single extra…

High Energy Physics - Phenomenology · Physics 2010-04-30 G. Ramalho , M. T. Pena

I review lattice-QCD calculations of the electromagnetic and generalized form factors (GFFs), which determine the transverse structure of the nucleon, and briefly comment on recent calculations related to transverse-momentum dependent…

High Energy Physics - Lattice · Physics 2010-11-19 Harvey B. Meyer

We perform a direct calculation of the gluon momentum fraction of the nucleon using maximally twisted mass fermion ensembles with $N_f=2+1+1$ flavors at a pion mass of about $370\,\mathrm{MeV}$ and a lattice spacing of $a\approx…

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

Nucleon isovector vector- and axialvector-current form factors, the renormalized isovector transversity and scalar charge, and the bare quark momentum and helicity moments of isovector structure functions are reported with improved…

High Energy Physics - Lattice · Physics 2019-08-15 Michael Abramczyk , Meifeng Lin , Andrew Lytle , Shigemi Ohta

We summarize four contributions about dynamical twisted mass fermions. The resulting report covers results for N_f=2 obtained from three different gauge actions, namely the standard Wilson plaquette gauge action, the DBW2 and the tree-level…

High Energy Physics - Lattice · Physics 2010-12-23 F. Farchioni , P. Hofmann , K. Jansen , I. Montvay , G. Munster , M. Papinutto , E. E. Scholz , L. Scorzato , A. Shindler , N. Ukita , C. Urbach , U. Wenger , I. Wetzorke

Some recent advances in the theoretical description of the Nucleon electromagnetic form factors, both in the space- and time-like regions, will be briefly illustrated. In particular, both the present stage of the lattice calculations and…

High Energy Physics - Phenomenology · Physics 2009-02-05 Giovanni Salmè

I review the results of a recent dispersion--theoretical analysis of the nucleon electromagnetic form factors and comment on the strangeness form factors. The need for a better data basis at low, intermediate and large momentum transfer is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ulf-G. Meißner

The strange form factors of the nucleon are studied in a two-component model consisting of a three-quark intrinsic structure surrounded by a meson cloud. A comparison with the available experimental world data from the SAMPLE, PVA4, HAPPEX…

Nuclear Theory · Physics 2014-11-18 R. Bijker

We present the analysis of isovector axial vector nucleon form factors on a set of $N_f=2+1$ CLS ensembles with $\mathcal O(a)$-improved Wilson fermions and L\"uscher-Weisz gauge action. The set of ensembles covers a pion mass range of…

High Energy Physics - Lattice · Physics 2021-12-02 Dalibor Djukanovic , Georg von Hippel , Jonna Koponen , Harvey B. Meyer , Konstantin Ottnad , Tobias Schulz , Hartmut Wittig

We compute the axial, scalar, tensor and pseudoscalar isovector couplings of the nucleon as well as the induced tensor and pseudoscalar charges in lattice simulations with $N_f=2$ mass-degenerate non-perturbatively improved…

Dispersion relations provide a powerful tool to describe the electromagnetic form factors of the nucleon both in the spacelike and timelike regions with constraints from unitarity and perturbative QCD. We give a brief introduction into…

High Energy Physics - Phenomenology · Physics 2014-11-17 H. -W. Hammer

We investigate the vector and scalar form factors relevant for K_{\ell 3} semileptonic decays using maximally twisted-mass fermions with two flavors of dynamical quarks (N_f = 2). The simulations cover pion masses as light as 260 MeV and…

High Energy Physics - Lattice · Physics 2010-12-17 V. Lubicz , F. Mescia , L. Orifici , S. Simula , C. Tarantino

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

About half the mass of a hadron is given from gluonic contributions. In this talk we calculate the chromo-electric and chromo-magnetic components of the nucleon mass. These computations are numerically difficult due to gluon field…

High Energy Physics - Lattice · Physics 2008-11-26 M. Goeckeler , R. Horsley , E. -M. Ilgenfritz , H. Oelrich , H. Perlt , P. E. L. Rakow , G. Schierholz , A. Schiller , P. Stephenson

In the framework of relativistic SU(2)_f baryon chiral perturbation theory we calculate the volume dependence of the nucleon mass up to and including O(p^4). Since the parameters in the resulting finite size formulae are fixed from the pion…

High Energy Physics - Lattice · Physics 2010-04-06 A. Ali Khan , T. Bakeyev , M. Göckeler , T. R. Hemmert , R. Horsley , A. C. Irving , B. Joó , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben

It is imperative that lattice QCD serve to develop our understanding of hadron structure and, where possible, to guide the interpretation of experimental data. There is now a great deal of effort directed at the calculation of the…

High Energy Physics - Lattice · Physics 2010-02-17 J. D. Ashley , D. B. Leinweber , A. W. Thomas , R. D. Young

Precise proton and neutron form factor measurements at Jefferson Lab, using spin observables, have recently made a significant contribution to the unraveling of the internal structure of the nucleon. Accurate experimental measurements of…

Nuclear Experiment · Physics 2015-06-02 V. Punjabi , C. F. Perdrisat , M. K. Jones , E. J. Brash , C. E. Carlson

Stress distributions in the deuteron are related to form factors of the asymmetric energy-momentum tensor through three-dimensional Fourier transforms. There are eleven such form factors, which we calculate in an impulse approximation. We…

Nuclear Theory · Physics 2026-05-28 Wim Cosyn , Adam Freese , Alan Sosa