English
Related papers

Related papers: Nucleon generalized form factors from two-flavor l…

200 papers

The nucleon electromagnetic form factors continue to be of major interest for experimentalists and phenomenologists alike. They provide important insights into the structure of nuclear matter. For a range of interesting momenta they can be…

We present a calculation of the Mellin moments of the transverse quark spin densities in the nucleon using lattice QCD. The densities are extracted from the unpolarized and transversity generalized form factors extrapolated to the continuum…

We present a quenched lattice calculation of the weak nucleon form factors: vector (F_V(q^2)), induced tensor (F_T(q^2)), axial-vector (F_A(q^2)) and induced pseudo-scalar (F_P(q^2)) form factors. Our simulations are performed on three…

High Energy Physics - Lattice · Physics 2009-04-10 Shoichi Sasaki , Takeshi Yamazaki

Momentum and spatial distributions of quarks and gluons inside hadrons are typically encoded in the so-called generalized parton distributions (GPDs). GPDs are multi-dimensional quantities that are very challenging to extract, both…

We present results for the nucleon electromagnetic form factors, including the momentum transfer dependence and derived quantities (charge radii and magnetic moment). The analysis is performed using O(a) improved Wilson fermions in Nf=2 QCD…

High Energy Physics - Lattice · Physics 2015-09-30 S. Capitani , M. Della Morte , D. Djukanovic , G. von Hippel , J. Hua , B. Jäger , B. Knippschild , H. B. Meyer , T. D. Rae , H. Wittig

Nucleon form factors at high momentum transfer |t| are treated in the framework of generalized parton distributions (GPD's). The possibility of obtaining information about parton high transverse momentum components by application of GPD's…

High Energy Physics - Phenomenology · Physics 2009-11-07 Pau Stoler

We present results for the electromagnetic form factors of the proton and neutron computed on the Coordinated Lattice Simulations (CLS) ensembles with $N_f = 2 + 1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an…

High Energy Physics - Lattice · Physics 2023-01-10 Miguel Salg , Dalibor Djukanovic , Georg von Hippel , Harvey B. Meyer , Konstantin Ottnad , Hartmut Wittig

We use the energy-momentum tensor (EMT) current to compute the EMT form factors of the nucleon in the framework of the light cone QCD sum rule formalism. In the calculations, we employ the most general form of the nucleon's interpolating…

High Energy Physics - Phenomenology · Physics 2020-03-18 K. Azizi , U. Ozdem

This talk presents recent calculations in full QCD of the lowest three moments of generalized parton distributions and the insight they provide into the behavior of nucleon electromagnetic form factors, the origin of the nucleon spin, and…

We give a brief overview of recent progress in lattice QCD simulations that is enabling precision studies of the three-dimensional structure of the nucleon. We present results on nucleon charges and second Mellin moments of parton…

High Energy Physics - Lattice · Physics 2024-08-27 Constantia Alexandrou

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 present the strange electromagnetic form factors of the nucleon using lattice QCD with $N_f=2+1+1$ twisted mass clover-improved fermions and quark masses tuned to their physical values. Using four ensembles with lattice spacings of…

We evaluate nucleon four-point functions in the framework of lattice QCD in order to extract the first Mellin moment of double parton distributions (DPDs) in the unpolarized proton. In this first study, we employ an nf = 2 + 1 ensemble with…

High Energy Physics - Lattice · Physics 2021-09-24 Gunnar S. Bali , Markus Diehl , Benjamin Gläßle , Andreas Schäfer , Christian Zimmermann

Using an approach free from momentum extrapolation, we calculate the nucleon magnetic moment and the fraction of the nucleon spin carried by the quark angular momentum in the quenched lattice QCD approximation. Quarks with three values of…

High Energy Physics - Lattice · Physics 2009-11-07 Valeriya Gadiyak , Xiangdong Ji , Chulwoo Jung

We present a simple empirical parameterization of the x- and t-dependence of generalized parton distributions at zero skewness, using forward parton distributions as input. A fit to experimental data for the Dirac, Pauli and axial form…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. Diehl , Th. Feldmann , R. Jakob , P. Kroll

We present a lattice measurement of the first two moments of the spin-dependent GPD H-tilde(x,xi,t). From these we obtain the axial coupling constant and the second moment of the spin-dependent forward parton distribution. The measurements…

We report isovector form factors and low moments of isovector structure functions of nucleon from the coarse RIKEN-BNL-Columbia (RBC) and UKQCD joint dynamical (2+1)-flavor domain-wall fermions (DWF) ensembles. The lattice cut off is…

High Energy Physics - Lattice · Physics 2008-10-02 Shigemi Ohta , Takeshi Yamazaki

In this work, we present a lattice QCD calculation of the Mellin moments of the twist-2 axial-vector generalized parton distribution (GPD), $\widetilde{H}(x,\xi,t)$, at zero skewness, $\xi$, with multiple values of the momentum transfer,…

The extraction of the magnetic form factor of the nucleon at zero momentum transfer is usually performed by adopting a parametrization for its momentum dependence and fitting the results obtained at finite momenta. We present a position…

High Energy Physics - Lattice · Physics 2016-11-08 Constantia Alexandrou , Martha Constantinou , Giannis Koutsou , Konstantin Ottnad , Marcus Petschlies

We present our progress on the computation of the axial form factor of the nucleon with flavour structure $u+d-2s$ from lattice QCD. We employ a set of $N_f=2+1$ CLS ensembles with $O(a)$-improved Wilson fermions and the L\"uscher-Weisz…