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Related papers: String-based axial and helicity-flip GPDs: a compa…

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The dual parametrization and the Mellin-Barnes integral approach represent two frameworks for handling the double partial wave expansion of generalized parton distributions (GPDs) in the conformal partial waves and in the $t$-channel ${\rm…

High Energy Physics - Phenomenology · Physics 2015-06-23 Dieter Müller , Maxim V. Polyakov , Kirill M. Semenov-Tian-Shansky

In recent years, there has been a breakthrough in lattice calculations of $x$-dependent partonic distributions. This encompasses also distributions describing the 3D structure of the nucleon, such as generalized parton distributions (GPDs).…

Results for the isovector axial form factors of the proton from a lattice QCD calculation are presented for both point-split and local currents. They are obtained on a quenched $16^{3} \times 24$ lattice at $\beta= 6.0$ with Wilson fermions…

High Energy Physics - Lattice · Physics 2009-09-25 K. F. Liu , S. J. Dong , T. Draper , J. M. Wu , W. Wilcox

We discuss techniques and results for the extraction of the nucleon's spin-dependent parton distributions and their uncertainties from data for polarized deep-inelastic lepton-nucleon and proton-proton scattering by means of a global QCD…

High Energy Physics - Phenomenology · Physics 2009-09-01 Daniel de Florian , Rodolfo Sassot , Marco Stratmann , Werner Vogelsang

The inclusion of QCD corrections to the Born amplitude of deeply virtual Compton scattering in both spacelike (DVCS) and timelike (TCS) regimes modifies the extraction process of generalized parton distributions (GPDs) from observables. In…

High Energy Physics - Phenomenology · Physics 2014-01-10 H. Moutarde , B. Pire , F. Sabatié , L. Szymanowski , J. Wagner

We report the first global extraction of generalized parton distributions (GPDs), GUMP1.0, by combining deeply virtual Compton scattering and $\rho$-meson production data from Jefferson Lab and Hadron-Electron Ring Accelerator with global…

High Energy Physics - Phenomenology · Physics 2025-09-11 Yuxun Guo , Fatma P. Aslan , Xiangdong Ji , M. Gabriel Santiago

We present a determination of the parton distributions of the nucleon from a global set of hard scattering data using the NNPDF methodology: NNPDF2.0. Experimental data include deep-inelastic scattering with the combined HERA-I dataset,…

High Energy Physics - Phenomenology · Physics 2014-11-20 Richard D. Ball , Luigi Del Debbio , Stefano Forte , Alberto Guffanti , Jose I. Latorre , Juan Rojo , Maria Ubiali

We present results for the nucleon's axial charge g_A and the first moment <x> of the unpolarized parton distribution function from a simulation of quenched overlap fermions.

High Energy Physics - Lattice · Physics 2008-11-26 M. Gürtler , R. Horsley , V. Linke , H. Perlt , P. E. L. Rakow , G. Schierholz , A. Schiller , T. Streuer

Recent precision spin structure data from Jefferson Lab have significantly advanced our knowledge of nucleon structure in the valence quark (high-$x$) region and improved our understanding of higher-twist effects, spin sum rules and…

Nuclear Experiment · Physics 2007-05-23 Jian-ping Chen

We present a physically motivated parametrization of the chiral-even generalized parton distributions in the non-singlet sector obtained from a global analysis using a set of available experimental data. Our analysis is valid in the…

High Energy Physics - Phenomenology · Physics 2011-08-12 Gary R. Goldstein , J. Osvaldo Gonzalez Hernandez , Simonetta Liuti

Previous Lattice QCD calculations of nucleon transverse momentum-dependent parton distributions (TMDs) focused on the case of transversely polarized nucleons, and thus did not encompass two leading-twist TMDs associated with longitudinal…

High Energy Physics - Lattice · Physics 2023-01-18 M. Engelhardt , N. Hasan , T. Izubuchi , C. Kallidonis , S. Krieg , S. Meinel , J. Negele , A. Pochinsky , G. Silvi , S. Syritsyn

By analyzing experimental data on semi-inclusive deep inelastic scattering off longitudinally polarized targets, we extract the transverse momentum dependence of the quark helicity distribution, i.e., the difference between the…

High Energy Physics - Phenomenology · Physics 2024-09-27 Alessandro Bacchetta , Alessia Bongallino , Matteo Cerutti , Marco Radici , Lorenzo Rossi

We present a first QCD analysis of next-to-next-leading-order (NNLO) contributions of the spin-dependent parton distribution functions (PPDFs) in the nucleon and their uncertainties using the Jacobi polynomial approach. Having the NNLO…

High Energy Physics - Phenomenology · Physics 2016-06-24 F. Taghavi Shahri , Hamzeh Khanpour , S. Atashbar Tehrani , Z. Alizadeh Yazdi

This is a review of progress in hadron structure physics from lattice QCD. Recent results on the structure of the nucleon and the pion in terms of (transition) form factors, moments of distribution amplitudes and (generalized) parton…

High Energy Physics - Lattice · Physics 2008-11-26 Philipp Hägler

We study the nonperturbative properties of the nucleon's chiral-odd generalized parton distributions (transversity GPDs) in the large-$N_c$ limit of QCD. This includes the parametric ordering of the spin-flavor components, the polynomiality…

High Energy Physics - Phenomenology · Physics 2024-11-27 June-Young Kim , Christian Weiss

Inspired by recent measurements with the CLAS detector at Jefferson Lab, we perform a self-consistent analysis of world data on the proton structure function g1 in the range 0.17 < Q2 < 30 (GeV/c)**2. We compute for the first time low-order…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Osipenko , S. Simula , W. Melnitchouk , P. Bosted , V. Burkert , E. Christy , K. Griffioen , C. Keppel , S. Kuhn , G. Ricco

The parity violation programs at MIT-Bates, Jefferson Lab and Mainz are presently focused on developing a better understanding of the sea-quark contributions to the vector matrix elements of nucleon structure. The success of these programs…

Nuclear Experiment · Physics 2015-06-26 E. J. Beise

Supposing only that there is an effective charge which defines an evolution scheme for parton distribution functions (DFs) that is all-orders exact, strict lower and upper bounds on all Mellin moments of the valence-quark DFs of pion-like…

High Energy Physics - Phenomenology · Physics 2022-06-01 Z. -F. Cui , M. Ding , J. M. Morgado , K. Raya , D. Binosi , L. Chang , F. De Soto , C. D. Roberts , J. Rodríguez-Quintero , S. M. Schmidt

Parton distribution functions (DFs) are defining expressions of hadron structure. Exploiting the role of effective charges in quantum chromodynamics, an algebraic scheme is described which, given any hadron's valence parton DFs at the…

High Energy Physics - Phenomenology · Physics 2023-06-07 Pei-Lin Yin , Yin-Zhen. XuID , Zhu-Fang Cui , Craig D. Roberts , José Rodríguez-Quintero

The structure of neutrons, protons, and other strongly interacting particles is now being calculated in full, unquenched lattice QCD with quark masses entering the chiral regime. This talk describes selected examples, including the nucleon…