English
Related papers

Related papers: Recoil effects on nucleon electromagnetic form fac…

200 papers

We compute the gluonic contribution to the gravitational form factors of the proton using the improved holographic QCD model, in which the proton is described in terms of bulk Dirac fermions. Model parameters are constrained using lattice…

High Energy Physics - Theory · Physics 2026-02-26 Antti Hippeläinen , Niko Jokela , Matti Järvinen

We compute the electromagnetic form factors of the proton and neutron using lattice QCD with $N_f = 2 + 1 + 1$ twisted mass clover-improved fermions and quark masses tuned to their physical values. Three ensembles with lattice spacings of…

High Energy Physics - Lattice · Physics 2025-02-18 Constantia Alexandrou , Simone Bacchio , Giannis Koutsou , Bhavna Prasad , Gregoris Spanoudes

Extended vector meson dominance model, that allows to describe the electromagnetic form factors of nucleons obeying the asymptotic quark counting rule prescriptions and contains the minimal number of free parameters, is presented. We get a…

High Energy Physics - Phenomenology · Physics 2014-11-20 Amand Faessler , M. I. Krivoruchenko , B. V. Martemyanov

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

The electric dipole form factor (EDFF) of the nucleon stemming from the QCD theta term and from the quark color-electric dipole moments is calculated in chiral perturbation theory to sub-leading order. This is the lowest order in which the…

High Energy Physics - Phenomenology · Physics 2011-01-27 E. Mereghetti , J. de Vries , W. H. Hockings , C. M. Maekawa , U. van Kolck

The electromagnetic form factors of a composite vector particle within the light-front formulation of the Mandelstam formula is investigated. In order to extract the form factors from the matrix elements of the plus component of the current…

High Energy Physics - Phenomenology · Physics 2018-12-26 J. P. B. C. de Melo

We examine isospin breaking in the nucleon wave functions due to the $u - d$ quark mass difference and the Coulomb interaction among the quarks, and their consequences on the nucleon electroweak form factors in a nonrelativistic constituent…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. Dmitrasinovic , S. J. Pollock

Starting with the VMD parametrization of the electric and magnetic nucleon form factors, which are saturated just by the ground state vector-mesons rho, omega and phi, then aplying the strict OZI rule and the asymptotic behaviour of form…

High Energy Physics - Phenomenology · Physics 2009-10-31 Peter Weisenpacher

The low-energy electromagnetic form factors of the $\Delta$(1232)-to-nucleon transition are derived combining dispersion theory techniques and chiral perturbation theory. The form factors are expressed in terms of the well-understood pion…

High Energy Physics - Phenomenology · Physics 2024-02-01 Moh Moh Aung , Stefan Leupold , Elisabetta Perotti , Yupeng Yan

We present results for the electromagnetic form factors of the proton and neutron computed on the $(2 + 1)$-flavor Coordinated Lattice Simulations (CLS) ensembles including both quark-connected and -disconnected contributions. The $Q^2$-,…

High Energy Physics - Lattice · Physics 2024-09-27 Miguel Salg , Dalibor Djukanovic , Georg von Hippel , Harvey B. Meyer , Konstantin Ottnad , Hartmut Wittig

We report on the contributions to the nucleon weak magnetic and electric form factors arising from isospin-breaking form factors. The relativized quark model used in the calculations includes isospin impurities in the large basis nucleon…

Nuclear Theory · Physics 2007-05-23 Simon Capstick , D. Robson

We present results for the isovector electromagnetic form factors of the nucleon computed on the CLS ensembles with $N_f=2+1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an $\mathcal{O}(a)$-improved vector current. The analysis…

High Energy Physics - Lattice · Physics 2021-06-02 D. Djukanovic , T. Harris , G. von Hippel , P. M. Junnarkar , H. B. Meyer , D. Mohler , K. Ottnad , T. Schulz , J. Wilhelm , H. Wittig

We study the low momentum behavior of nucleon gravitational form factors in the framework of the heavy baryon chiral perturbation theory. At zero recoil they determine the momentum and spin apportion between nucleon constituents. Our result…

High Energy Physics - Phenomenology · Physics 2011-07-19 A. V. Belitsky , X. Ji

This paper calculates the elastic form factors for nucleons based on generalized parton distributions using an extended new ansatz introduced in http://dx.doi.org/10.1103/PhysRevC.105.025202 (Phys. Rev. C 105, no.2, 025202 (2022)).…

High Energy Physics - Phenomenology · Physics 2023-06-06 Hossein Vaziri , Mohammad Reza Shojaei

The nucleon electromagnetic form factors have been studied in the past extensively from unpolarized electron scattering experiments. With the development in polarized beam, recoil polarimetry, and polarized target technologies, polarization…

Nuclear Experiment · Physics 2009-11-10 Haiyan Gao

The pion and kaon electromagnetic form factors $F_M(Q^2)$ are calculated at the leading order of pQCD using the running coupling constant method. In calculations a dependence of the mesons distribution amplitudes on the hard scale $Q^2$ is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Shahin S. Agaev

It is demonstrated that an emission of collinear photons by the polarized initial electron in elastic electron-proton polarization transfer scattering leads to an apparent shifting of real events with small momentum transfer into the data…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Dubnička , E. Kuraev , M. Sečanský , A. Vinnikov

Accessing hadronic form factors at large momentum transfers has traditionally presented a challenge for lattice QCD simulations. Here we demonstrate how a novel implementation of the Feynman-Hellmann method can be employed to calculate…

Results for all elastic electroweak nucleon form factors are presented for the chiral constituent quark model based on Goldstone-boson-exchange dynamics. The calculations are performed in a covariant framework using the point-form approach…

High Energy Physics - Phenomenology · Physics 2017-08-23 S. Boffi , M. Radici , L. Glozman , W. Plessas , R. F. Wagenbrunn , W. Klink

The complete world set of parity violating electron scattering data up to Q^2~0.3 GeV^2 is analysed. We extract the current experimental determination of the strange electric and magnetic form factors of the proton, as well as the weak…

Nuclear Experiment · Physics 2010-02-17 R. D. Young , J. Roche , R. D. Carlini , A. W. Thomas
‹ Prev 1 8 9 10 Next ›