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Related papers: Gluon Polarization In Nucleon

200 papers

In order to determine polarized parton densities in nucleon we have made fits using all experimental data on spin asymmetries measured in the deep inelastic scattering on different nucleon targets. We have used in our analysis next to…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Bartelski , S. Tatur

We compute the gluon polarization $\Delta G$ and the gluon total angular momentum $J_g$ in the Isgur-Karl quark model. Taking into account self-interaction contributions, we obtain for both quantities a positive value of about 0.24 at the…

High Energy Physics - Phenomenology · Physics 2009-10-31 V. Barone , T. Calarco , A. Drago

The gluon polarization $\Delta{G}/G$ is the key to a further clarification of the spin structure of the nucleon. The COMPASS collaboration at CERN has set out to undertake the direct determination of this quantity. It accesses the gluon…

High Energy Physics - Experiment · Physics 2019-08-14 Yann Bedfer

Using the recently proposed $gg\eta'$ effective vertex, we investigate the production of $\eta'$ from gluon fusion in polarized pp collisions. We show that by measuring $A_{LL}$ in $\eta'$ production, one can extract the polarized gluon…

High Energy Physics - Phenomenology · Physics 2009-11-07 Sangyong Jeon , Jamal Jalilian-Marian

We give an overview of the current status of investigations of the polarization of gluons in the nucleon. We describe some of the physics of the spin-dependent gluon parton distribution and its phenomenology in high-energy polarized…

High Energy Physics - Phenomenology · Physics 2008-11-26 Marco Stratmann , Werner Vogelsang

We present a determination of the gluon polarization Delta G/G in the nucleon, based on the helicity asymmetry of quasi-real photoproduction events, Q^2<1(GeV/c)^2, with a pair of large transverse-momentum hadrons in the final state. The…

High Energy Physics - Experiment · Physics 2008-11-26 COMPASS Collaboration , E. S. Ageev

The fundamental program in high energy spin physics focuses on the spin structure of the nucleon. The gluon and orbital angular momentum components of the nucleon spin are virtually unknown. The J_z=1/2 sum rule involves the integrated…

High Energy Physics - Phenomenology · Physics 2017-08-23 Gordon P. Ramsey

We show that the gluon distribution function for very large nuclei may be computed for small transverse momentum as correlation functions of an ultraviolet finite two dimensional Euclidean field theory. This computation is valid to all…

High Energy Physics - Phenomenology · Physics 2009-10-22 Larry McLerran , Raju Venugopalan

I begin with a general discussion about importance of constructing a picture of the nucleon in terms of QCD degrees of freedom, emphasizing the role of spin structure functions. I then give a short overview on the theoretical and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xiangdong Ji

We present a general analysis of the orbital angular momentum (OAM) distribution of gluons $L_g(x)$ inside the nucleon with particular emphasis on the small-$x$ region. We derive a novel operator representation of $L_g(x)$ in terms of…

High Energy Physics - Phenomenology · Physics 2017-07-05 Yoshitaka Hatta , Yuya Nakagawa , Bowen Xiao , Feng Yuan , Yong Zhao

The gluon polarisation in the nucleon has been determined by detecting charm production via D0 meson decay to charged K and pi in polarised muon scattering off a longitudinally polarised deuteron target. The data were taken by the COMPASS…

High Energy Physics - Experiment · Physics 2009-07-30 COMPASS Collaboration , M. Alekseev

We obtain the gluon parton distribution functions (PDFs) in the proton within the extended light-front holographic QCD framework, where the proton couples with the spin-two Pomeron in Anti-de Sitter space, together with constraints imposed…

High Energy Physics - Phenomenology · Physics 2023-03-29 Bheemsehan Gurjar , Chandan Mondal , Dipankar Chakrabarti

We propose to access the gluon polarization $\Delta G$ by measuring the cross section spin-asymmetry in semi-inclusive polarized lepton -- nucleon scattering. The photon-gluon fusion sub-process will be tagged by detecting high-$p_T$…

High Energy Physics - Phenomenology · Physics 2009-10-30 A. Bravar , D. von Harrach , A. Kotzinian

We present the first measurement of the gluon polarisation in the nucleon based on the photon-gluon fusion process tagged by charmed meson production and decay to charged K and pi. The data were collected in polarised muon scattering off a…

High Energy Physics - Experiment · Physics 2008-02-22 COMPASS Collaboration , M. Alekseev

In order to get information about the polarized gluon distribution in a proton, we studied the electroproduction of \psi' in polarized electron and polarized proton collisions in the framework of the NRQCD factorization approach. The value…

High Energy Physics - Phenomenology · Physics 2011-03-23 Kazutaka Sudoh , Han-Wen Huang , Toshiyuki Morii

The total gluon helicity in a polarized proton, measurable in high-energy scattering, is shown to be the large momentum limit of a gauge-invariant but non-local, frame-dependent gluon spin $\vec{E}\times \vec{A}_\perp$ in QCD. This opens a…

High Energy Physics - Phenomenology · Physics 2013-09-16 Xiangdong Ji , Jian-Hui Zhang , Yong Zhao

We review the theoretical foundations of the quantum statistical approach to parton distributions and we show that by using some recent experimental results from Deep Inelastic Scattering, we are able to improve the description of the data…

High Energy Physics - Phenomenology · Physics 2015-06-23 Jacques Soffer , Claude Bourrely , Franco Buccella

A fit to proton, neutron and deuteron spin asymmetries is presented and polarized parton distributions in nucleon are given. These densities have their roots in the MRS fit for unpolarized case. The integrals of polarized distributions are…

High Energy Physics - Phenomenology · Physics 2008-02-03 Jan Bartelski , Stanisław Tatur

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

Measurements involving the gluon spin density, Delta G=G++ - G+-, can play an important role in the quantitative understanding of proton structure. To demonstrate this, we show that the shape of the gluon asymmetry, A(x,t)=Delta…

High Energy Physics - Phenomenology · Physics 2011-07-27 Yevgeny Binder , Gordon P. Ramsey , Dennis Sivers