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Related papers: A QCD Analysis of Polarised Parton Densities

200 papers

We present results on the quark and gluon polarization in the nucleon obtained in a combined next to leading order analysis to the available inclusive and semi-inclusive polarized deep inelastic scattering data.

High Energy Physics - Phenomenology · Physics 2015-06-25 D. de Florian , G. A. Navarro , R. Sassot

The latest measurements of $F_2$ at HERA allow for a {\it combination} of gluon and sea quark distributions at small $x$ that is significantly different from those of existing parton sets. We perform a new global fit to deep-inelastic and…

High Energy Physics - Phenomenology · Physics 2016-09-01 A. D. Martin , R. G. Roberts , W. J. Stirling

Data from the HERA collider experiments, H1 and ZEUS, have been fundamental to the rapid recent development of our understanding of the partonic composition of the proton and of QCD. This report focuses on inclusive measurements of neutral…

High Energy Physics - Experiment · Physics 2014-11-17 P. Newman

The results of a recent next-to-leading order QCD analysis of the world data on polarized deep inelastic scattering are reported. New parameterizations are derived for the quark and gluon distributions, accounting for the massive Wilson…

High Energy Physics - Phenomenology · Physics 2015-05-20 Johannes Blümlein , Helmut Böttcher

We perform a novel type of analysis of diffractive deep-inelastic scattering data, in which the input parton distributions of the Pomeron are parameterised using the perturbative QCD expressions. In particular, we treat individually the…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. D. Martin , M. G. Ryskin , G. Watt

We have carried out a NLO analysis of the world data on polarized DIS in the MS/bare scheme. We have studied two models of the parametrizations of the input parton densities, the first due to Brodsky, Burkhardt and Schmidt (BBS) which gives…

High Energy Physics - Phenomenology · Physics 2009-10-30 E. Leader , A. V. Sidorov , D. B. Stamenov

This article introduces {\tt AAK24}, a Next-to-Leading Order (NLO) QCD analysis of polarized data from both polarized Deep Inelastic Scattering (DIS) and Semi-Inclusive Deep Inelastic Scattering (SIDIS) experiments on the nucleon. The {\tt…

High Energy Physics - Phenomenology · Physics 2024-09-24 Fatemeh Arbabifar , Shahin Atashbar Tehrani , Hamzeh Khanpour

Motivated by the possibility that it may be misleading to assume SU(3) symmetry in the analysis of hyperon \beta-decays, we study the sensitivity of the polarized parton densities, derived from the world data on inclusive polarized deep…

High Energy Physics - Phenomenology · Physics 2009-10-31 E. Leader , A. V. Sidorov , D. B. Stamenov

A recent global QCD analysis of jet production and other polarized scattering data has found the presence of negative solutions for the gluon helicity distribution in the proton, $\Delta g$, along with the traditional $\Delta g > 0$…

High Energy Physics - Phenomenology · Physics 2026-05-04 R. M. Whitehill , Yiyu Zhou , N. Sato , W. Melnitchouk

The recent global analysis of helicity parton distributions, which takes into account available data from inclusive and semi-inclusive polarized deep inelastic scattering, as well as from polarized proton-proton scattering at RHIC, appears…

High Energy Physics - Phenomenology · Physics 2010-03-15 M. Wakamatsu

We discuss the production of hadrons in polarized lepton nucleon interactions and in the current jet fragmentation region; using the QCD hard scattering formalism we compute the helicity density matrix of the hadron and show how its…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Anselmino , M. Boglione , J. Hansson , F. Murgia

We present the first simultaneous global QCD analysis of spin-dependent parton distribution functions alongside their spin-averaged counterparts and pion, kaon, and unidentified hadron fragmentation functions. This analysis includes all…

High Energy Physics - Phenomenology · Physics 2023-09-08 C. Cocuzza , W. Melnitchouk , A. Metz , N. Sato

We compare constraints on the gluon polarization in the nucleon obtained in next to leading order global QCD fits to polarized deep inelastic scattering data with those coming from observables more directly linked to the gluon polarization,…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. A. Navarro , R. Sassot

We perform a global leading-order QCD fit to recent polarized structure function data in order to extract a consistent set of spin-dependent parton distributions. Assuming that there is no significant intrinsic polarization of the quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Gehrmann , W. J. Stirling

Polarized deep--inelastic scattering data on longitudinally polarized hydrogen and deuterium targets have been used to determine double spin asymmetries of cross sections. Inclusive and semi--inclusive asymmetries for the production of…

High Energy Physics - Experiment · Physics 2012-08-03 HERMES Collaboration , A. Airapetian

A simultaneous Electroweak and QCD fit of electroweak parameters and parton distribution functions to HERA data on deep inelastic scattering is presented. The input data are neutral current and charged current inclusive cross sections…

High Energy Physics - Experiment · Physics 2016-09-29 I. Abt , A. M. Cooper-Sarkar , B. Foster , C. Gwenlan , V. Myronenko , O. Turkot , K. Wichmann

We perform a combined next to leading order analysis to both inclusive and semi-inclusive polarized deep inelastic scattering data, assessing the impact of new data in the extraction of the sea quark and gluon spin dependent densities. In…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. de Florian , R. Sassot

Polarized deep inelastic scattering (DIS) data are analyzed in leading and next-to-leading order of QCD within the common `standard' scenario of polarized parton distributions with a flavor-symmetric light sea (antiquark) distribution…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Gluck , E. Reya , M. Stratmann , W. Vogelsang

Double-spin asymmetries of semi-inclusive cross sections for the production of identified pions and kaons have been measured in deep-inelastic scattering of polarized positrons on a polarized deuterium target. Five helicity distributions…

High Energy Physics - Experiment · Physics 2009-04-15 HERMES collaboration , A. Airapetian

We present a program to measure the parton densities in the pomeron using diffractive deep inelastic scattering and diffractive photoproduction, and to test the resulting parton densities by applying them to other processes such as the…

High Energy Physics - Phenomenology · Physics 2009-12-30 John Collins , Joey Huston , Jon Pumplin , Harry Weerts , Jim Whitmore