English
Related papers

Related papers: A QCD Analysis of Polarised Parton Densities

200 papers

The present talk summarises the 1993 situation in understanding the spin structure of the nucleon via electron and muon polarised deep--inelastic scattering (PDIS). The central question I shall address here is if the data can be interpreted…

High Energy Physics - Phenomenology · Physics 2007-05-23 Paolo M. Gensini

An updated next-to-leading order (NLO) QCD analysis of all presently available longitudinally polarized deep-inelastic scattering (DIS) data is presented in the framework of the radiative parton model.

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Stratmann

We consider the possibility of a direct determination of the polarized gluon density in the proton using charm production with polarized beams at HERA. We study total cross sections and distributions at leading order using different…

High Energy Physics - Phenomenology · Physics 2011-07-19 S. Frixione , G. Ridolfi

The HERMES experiment has measured double spin asymmetries of inclusive and semi-inclusive cross sections for the production of charged hadrons in deep-inelastic scattering of polarised positrons on polarised hydrogen and deuterium targets,…

High Energy Physics - Experiment · Physics 2017-08-23 Marc Beckmann

We present estimates of possible data on spin-dependent asymmetries in inclusive scattering of high energy polarized electrons by high energy polarized protons at HERA with their statistical errors and discuss systematic errors. We show…

High Energy Physics - Phenomenology · Physics 2011-09-13 A. De Roeck , A. Deshpande , V. W. Hughes , J. Lichtenstadt , G. Radel

We present a novel analysis of diffractive DIS data, in which the input parton distributions of the Pomeron are parameterised using perturbative QCD expressions. In addition to the usual two-gluon model for the perturbative Pomeron, we…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. Watt , A. D. Martin , M. G. Ryskin

We present estimates of possible data on spin-dependent asymmetries in inclusive scattering of high energy polarized electrons by high energy polarized protons at HERA, including statistical errors, and discuss systematic uncertainties. We…

High Energy Physics - Phenomenology · Physics 2007-05-23 Richard D. Ball , Abhay Deshpande , Stefano Forte , Vernon W. Hughes , Jechiel Lichtenstadt , Giovanni Ridolfi

We study the inclusive production of bottom-flavored hadrons from semileptonic decays of polarized top quarks at next-to-leading order in QCD using fragmentation functions recently determined from a global fit to $e^+e^-$ data. We provide…

High Energy Physics - Phenomenology · Physics 2021-03-03 Bernd A. Kniehl , S. Mohammad Moosavi Nejad

We review the present status of polarized structure functions measured in deep-inelastic scattering. We discuss the x and Q^2 dependence of the structure function g_1, and how it can be used to test perturbative QCD at next-to-leading order…

High Energy Physics - Phenomenology · Physics 2008-02-03 Stefano Forte

We perform QCD fit of the nucleon strange and anti-strange sea distributions to the neutrino and anti-neutrino dimuon data by the CCFR and NuTeV collaborations, supplemented by the inclusive charged lepton-nucleon Deep Inelastic Scattering…

High Energy Physics - Phenomenology · Physics 2009-10-21 S. Alekhin , S. Kulagin , R. Petti

The results on polarized parton densities (PDFs) obtained using different methods of QCD analysis of the present polarized DIS data are discussed. Their dependence on the method used in the analysis, accounting or not for the kinematic and…

High Energy Physics - Phenomenology · Physics 2009-11-05 Elliot Leader , Aleksander V. Sidorov , Dimiter B. Stamenov

The quantum statistical parton distributions approach proposed more than one decade ago is revisited by considering a larger set of recent and accurate Deep Inelastic Scattering experimental results. It enables us to improve the description…

High Energy Physics - Phenomenology · Physics 2017-04-05 Jacques Soffer , Claude Bourrely

Inclusive and semi-inclusive deep inelastic leptoproduction offers possibilities to study details of the quark and gluon structure of the hadrons involved. In many of these experiments polarization is an essential ingredient. We also…

Nuclear Theory · Physics 2007-05-23 P. J. Mulders

Semi-inclusive deep inelastic scattering of polarized leptons off hadrons enables one to measure the antisymmetric part of the hadron tensor. For unpolarized hadrons this piece is odd under time reversal. In deep inelastic scattering it…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. Levelt , P. J. Mulders

We study an influence of precise data on uncertainty of polarized parton distribution functions. This analysis includes the SLAC-E155 proton target data which are precise measurements. Polarized PDF uncertainties are estimated by using the…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Hirai

We have re-analyzed the world data on inclusive polarized DIS, in both NLO and LO QCD, including the very precise JLab Hall A neutron data, and have studied the role of positivity constraints, and demonstrated their importance, in…

High Energy Physics - Phenomenology · Physics 2010-02-03 Elliot Leader , Aleksander V. Sidorov , Dimiter B. Stamenov

The asymptotic collinear factorisation theorem, which holds for diffractive deep-inelastic scattering, has important modifications in the sub-asymptotic HERA regime. We use perturbative QCD to quantify these modifications. The diffractive…

High Energy Physics - Phenomenology · Physics 2010-03-25 A. D. Martin , M. G. Ryskin , G. Watt

We argue that coherent production of hard dijets by linearly polarized real photons can provide direct evidence for chirality violation in hard processes, the first measurement of the magnetic susceptibility of the quark condensate and the…

High Energy Physics - Phenomenology · Physics 2009-11-07 V. M. Braun , S. Gottwald , D. Yu. Ivanov , A. Schäfer , L. Szymanowski

We perform the first simultaneous global QCD analysis of spin-averaged and spin-dependent parton distribution functions (PDFs), including single jet production data from unpolarized and polarized hadron collisions. We critically assess the…

High Energy Physics - Phenomenology · Physics 2022-04-27 Y. Zhou , N. Sato , W. Melnitchouk

This talk covers three contributions from H1: "Measurement of the inclusive e^\pm p scattering cross section at high inelasticity y and of the structure function F_L", "Determination of the integrated luminosity at HERA using elastic QED…

High Energy Physics - Experiment · Physics 2019-08-14 Zhiqing Zhang