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Related papers: Nucleon spin structure from lattice QCD

200 papers

The nucleon spin structure is studied at COMPASS via the measurement of the spin dependent properties of deep inelastic muon-deuteron scattering. Both inclusive and semi-inclusive observables are investigated, with the emphasis put on the…

High Energy Physics - Experiment · Physics 2015-06-25 Yann Bedfer

We give a general introduction and discussion of the issues involved in using the twisted mass formulation of lattice fermions in the context of disconnected loop calculations, including a short orientation on the present experimental…

High Energy Physics - Lattice · Physics 2007-05-23 Walter Wilcox , Dean Darnell , Ron Morgan , Randy Lewis

We present the key results from the first study of the $x$-dependent nucleon gluon distribution from lattice QCD extrapolated to the physical-continuum limit. We use ensembles with $2+1+1$ flavors of highly improved staggered quarks (HISQ)…

High Energy Physics - Lattice · Physics 2023-07-14 William Good , Zhouyou Fan , Huey-Wen Lin

A future Electron-Ion Collider will enable the gluon contributions to the gravitational form factors of the proton to be constrained experimentally for the first time. Here, the first calculation of these form factors from lattice Quantum…

High Energy Physics - Lattice · Physics 2019-01-30 P. E. Shanahan , W. Detmold

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 study the operator description of the gluon spin contribution ($\Gamma$) to the nucleon's spin as it is measured in deep inelastic processes. $\Gamma$ can be related to the forward matrix element of a local gluon operator in $A^+=0$…

High Energy Physics - Phenomenology · Physics 2009-07-09 R. L. Jaffe

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

Parallel to the construction of gauge invariant spin and orbital angular momentum for QED in paper (I) of this series, we present here an analogous but non-trivial solution for QCD. Explicitly gauge invariant spin and orbital angular…

High Energy Physics - Phenomenology · Physics 2015-06-30 X. S. Chen , X. F. Lü , W. M. Sun , F. Wang , T. Goldman

We investigate the quark mass dependence of the nucleon mass M_N. An interpolation of this observable, between a selected set of fully dynamical two-flavor lattice QCD data and its physical value, is studied using relativistic baryon chiral…

High Energy Physics - Lattice · Physics 2009-11-10 M. Procura , T. R. Hemmert , W. Weise

We present results of lattice QCD simulations with mass-degenerate up and down and mass-split strange and charm (Nf=2+1+1) dynamical quarks using Wilson twisted mass fermions at maximal twist. The tuning of the strange and charm quark…

We present results on the axial and the electromagnetic form factors of the nucleon, as well as, on the first moments of the nucleon generalized parton distributions using maximally twisted mass fermions. We analyze two N_f=2+1+1 ensembles…

High Energy Physics - Lattice · Physics 2013-08-09 C. Alexandrou , M. Constantinou , S. Dinter , V. Drach , K. Jansen , C. Kallidonis , G. Koutsou

Quantum Chromodynamics on a lattice with Wilson fermions and a chirally twisted mass term for two degenerate quark flavours is considered in the framework of chiral perturbation theory. The pion masses and decay constants are calculated in…

High Energy Physics - Lattice · Physics 2010-12-23 Gernot Münster , Christian Schmidt , Enno E. Scholz

We present a lattice QCD calculation of the nucleon electric polarizabilities at the physical pion mass. Our findings reveal the substantial contributions of the $N\pi$ states to these polarizabilities. Without considering these…

High Energy Physics - Lattice · Physics 2024-09-02 Xuan-He Wang , Zhao-Long Zhang , Xiong-Hui Cao , Cong-Ling Fan , Xu Feng , Yu-Sheng Gao , Lu-Chang Jin , Chuan Liu

We present the current status of a non-perturbative lattice calculation of the moments of the pion and kaon distribution amplitudes by the RQCD collaboration. Our investigation is carried out using $N_f=2+1$ dynamical, non-perturbatively…

Our knowledge of the nucleon spin structure has greatly improved over the last twenty years or so, but still many fundamental questions remain unsolved. I will try to review some of the puzzling aspects of the structure of the nucleon spin,…

High Energy Physics - Phenomenology · Physics 2007-12-18 Jacques Soffer

We review results on hadron structure using lattice QCD simulations with pion masses close or at to the physical value. We pay particular attention to recent successes on the computation of the mass of the low-lying baryons and on the…

High Energy Physics - Lattice · Physics 2014-11-18 Constantia Alexandrou

Recent work unambiguously resolves the level of charge symmetry violation in moments of parton distributions using 2+1-flavor lattice QCD. We introduce the methods used for that analysis by applying them to determine the strong contribution…

Nuclear Theory · Physics 2015-06-18 R. D. Young , P. E. Shanahan , A. W. Thomas

Recent results on pion physics from lattice QCD are reviewed. We discuss quark mass dependences of pion mass and decay constant and compare them with the predictions from chiral perturbation theory. In particular we focus on the convergence…

High Energy Physics - Lattice · Physics 2014-11-20 Sinya Aoki

We present a recent calculation of the quark and gluon contributions to the angular momentum of a composite spin -$1/2$ state in QCD. The state we consider is a quark dressed with a gluon, and we use the two-component framework in…

High Energy Physics - Phenomenology · Physics 2024-07-22 Ravi Singh , Sudeep Saha , Asmita Mukherjee , Nilmani Mathur

We present the first calculation in lattice QCD of the lowest two moments of transverse spin densities of quarks in the nucleon. They encode correlations between quark spin and orbital angular momentum. Our dynamical simulations are based…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , Ph. Hägler , R. Horsley , Y. Nakamura , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , H. Stüben , J. M. Zanotti