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Related papers: Polarized Parton Densities and Processes

200 papers

Spin effects in high energy fragmentation processes can provide us with important information on hadronization mechanisms and spin structure of hadrons. It can in particular give new tests to the hadronization models. In this talk, we make…

High Energy Physics - Phenomenology · Physics 2007-05-23 Liang Zuo-tang

By assuming that there is no significant intrinsic polarization of the gluon, we have computed the polarized quark contributions to the proton's spin under SU(3) flavor symmetry breaking for the polarized sea and have performed a global…

High Energy Physics - Phenomenology · Physics 2009-10-28 Chung-Yi Wu

We calculate next to leading order QCD corrections to semi-inclusive polarized deep inelastic scattering and $e^+e^-$ annihilation cross sections for processes where the polarization of the identified final-state hadron can also be…

High Energy Physics - Phenomenology · Physics 2009-10-28 D. de Florian , R. Sassot

Recent results from the HERA ep collider are reviewed in these proceedings. The results are from measurements that probe QCD at high-energy scales, as defined by $Q^2$, the four-momentum-transfer squared of the collisions. These…

High Energy Physics - Experiment · Physics 2009-11-05 J. Ferrando

The physics case is summarised for the investigation of high energy spin phenomena by placing an internal polarised target into HERA's unpolarised proton beam. The luminosity and experimental sensitivity are discussed. Estimating the…

High Energy Physics - Phenomenology · Physics 2016-09-01 Wolf-Dieter Nowak

Spin and polarization are central to precision tests of fundamental physics and for interpreting radiation from astrophysical sources and ultraintense laser-matter experiments. Predictive modeling therefore requires not only energy spectra,…

High Energy Physics - Phenomenology · Physics 2026-03-13 Samuele Montefiori , Antonino Di Piazza , Tobias Podszus , Christoph H. Keitel , Matteo Tamburini

The study of the longitudinal polarization of Lambda and Lambda-bar hyperons produced in polarized deep inelastic scattering, neutrino scattering, and in Z0 decays allows to access the spin dynamics of the quark fragmentation process.…

High Energy Physics - Phenomenology · Physics 2011-09-13 A. Kotzinian , A. Bravar , D. von Harrach

Recently determined next-to-leading order sets of polarized parton distributions are used to study large-p_T $\vec{p}\vec{p}\rightarrow \gamma+X$ at $\sqrt{s}=38, 100 and 500 GeV$. Certain conversion terms, necessary to use the above sets,…

High Energy Physics - Phenomenology · Physics 2009-10-30 A. P. Contogouris , Z. Merebashvili

Recent measurements, in particular those on $\Lambda$ polarization and spin alignment of vector mesons in $e^+e^-$ annihilation at LEP, and those on the azimuthal asymmetry at HERA, have attracted much attention on the spin effects in high…

High Energy Physics - Phenomenology · Physics 2009-11-07 Zuo-tang Liang

The measurement of hard scattering processes, meaning those with energy scales of more than a few GeV, is the main method by which physics is being explored and extended by the experiments at the Large Hadron Collider. We review the…

High Energy Physics - Experiment · Physics 2015-06-04 Jonathan M. Butterworth , Guenther Dissertori , Gavin P. Salam

Results on elastic vector meson production at HERA are presented in the framework of perturbative QCD. The energy dependence of the cross section for J/Psi photoproduction and for rho electroproduction is studied. A full polarisation…

High Energy Physics - Phenomenology · Physics 2007-05-23 Barbara Clerbaux

The parton momentum density distributions in the proton are determined from a next-to-leading order QCD analysis of structure functions measured at HERA and by fixed target experiments. Also included are data on the difference of the up and…

High Energy Physics - Phenomenology · Physics 2011-09-13 M. Botje

Measurements of polarized electron-nucleon scattering can be realized at the TESLA linear collider facility with projected luminosities that are about two orders of magnitude higher than those expected of other experiments at comparable…

We present all relevant details of our calculation of the complete next-to-leading order (O(alpha_s^2 alpha)) QCD corrections to heavy flavor photoproduction with longitudinally polarized point-like photons and hadrons. In particular we…

High Energy Physics - Phenomenology · Physics 2011-01-25 I. Bojak , M. Stratmann

I show that factorization for hard processes in QCD is also valid when the detected particles are polarized, and that the proof of the theorem determines the operator form for the parton densities. Particular attention is given to the case…

High Energy Physics - Phenomenology · Physics 2009-10-22 John C. Collins

The problem of our understanding of the spin structure of the nucleon has been with us since the publication of the EMC measurements of the polarised structure function of the proton in 1987. In this talk a review of the results presented…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Gehrmann , T. Sloan

By taking the spin and polarization of the electrons, positrons and photons into account in the strong-field QED processes of nonlinear Compton emission and pair production, we find that the growth rate of QED cascades in ultra-intense…

High Energy Physics - Phenomenology · Physics 2021-06-01 Daniel Seipt , Christopher P. Ridgers , Dario Del Sorbo , Alec G. R. Thomas

Spin-1 hadrons contain different aspects of spin physics from the ones of the spin-1/2 nucleon because of the existence of tensor-polarized structure functions. In the charged-lepton deep inelastic scattering from a spin-1 hadron or…

High Energy Physics - Phenomenology · Physics 2026-01-27 S. Kumano

We present a quantitative assessment of the impact a future electron-ion collider will have on determinations of helicity quark and gluon densities and their contributions to the proton spin. Our results are obtained by performing a series…

High Energy Physics - Phenomenology · Physics 2013-05-30 Elke C. Aschenauer , Rodolfo Sassot , Marco Stratmann

We have made next to leading order QCD fit to the deep inelastic spin asymmetries on nucleons and we have determined polarised quark and gluon densities. The functional form for such distributions was inspired by the unpolarised ones given…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Bartelski , S. Tatur