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Related papers: The Spin Structure of the Proton

200 papers

Considerable progress has been made in our knowledge of the spin distribution within the proton. The recently measured limits on polarized gluons in the proton suggest polarized gluons contribute very modestly to the proton spin. We will…

High Energy Physics - Phenomenology · Physics 2009-08-24 F. Myhrer

The spin structure of the nucleon is studied in a light-cone description of the nucleon where the Fock expansion is truncated to consider only valence quarks. Transverse momentum dependent parton distributions and transverse-spin densities,…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Pasquini

One of the important questions in high energy physics is the relation of quark and gluon spin to that of the nucleons which they comprise. Polarization experiments provide a mechanism to probe the spin properties of elementary particles and…

High Energy Physics - Phenomenology · Physics 2014-11-17 Gordon P. Ramsey

We present preliminary results on the proton spin structure function at zero momentum, in the quenched approximation. Our calculation makes use of a nonperturbative means of determining the multiplicative renormalization of the topological…

High Energy Physics - Lattice · Physics 2009-10-22 B. Alles , M. Campostrini , L. Del Debbio , A. Di Giacomo , H. Panagopoulos , E. Vicari

We briefly review some of the recent developments in QCD spin physics.

High Energy Physics - Phenomenology · Physics 2007-05-23 Werner Vogelsang

We review recent progress on lattice calculations of nucleon spin structure, including the parton distribution functions, form factors, generalization parton distributions, and recent developments in lattice techniques.

High Energy Physics - Lattice · Physics 2009-08-24 Huey-Wen Lin

Effect of the quark intrinsic motion on the proton spin structure functions is demonstrated. It is shown, that the covariant version of the quark-parton model taking into account the orbital motion gives the consistent picture of the proton…

High Energy Physics - Phenomenology · Physics 2007-05-23 Petr Zavada

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 brief history of the subject is…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. J. Mulders , T. Sloan

We present a novel approach for investigating the spin structure of hadrons based on the two-point function in quantum field theory. In a rotating frame, we derive two independent expressions of the two-point function and identify their…

High Energy Physics - Phenomenology · Physics 2025-03-27 HyungJoo Kim , Philipp Gubler , Chihiro Sasaki

We generalize the Bartels-Ermolaev-Ryskin approach for the $g_1$ structure function at small-$x$ to determine the small-$x$ asymptotic behavior of the orbital angular momentum distributions in QCD. We present an exact analytical solution of…

High Energy Physics - Phenomenology · Physics 2019-09-04 Renaud Boussarie , Yoshitaka Hatta , Feng Yuan

We examine the present status of the Bjorken sum rule in the light of recent data on the spin structure functions of the proton, neutron and deuteron obtained by the CERN and SLAC experimental groups. We also discuss the role of possible…

High Energy Physics - Phenomenology · Physics 2008-02-03 Philip G. Ratcliffe

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

I present a review of the current status and the most recent achievements in lattice QCD calculations of hadron structure. First, I overview the status and systematic uncertainties of nucleon structure "benchmark" quantities that are well…

High Energy Physics - Lattice · Physics 2014-03-20 Sergey Syritsyn

The alternative to the standard formulation of the quark-parton model is proposed. Our relativistically covariant approach is based on the solution of the master equations relating the structure and distribution functions, which…

High Energy Physics - Phenomenology · Physics 2007-05-23 Petr Zavada

The proton spin crisis remains an unsolved problem in particle physics. The spin and angular momentum of the partons inside the proton are non-perturbative quantities in QCD which cannot be calculated by using the perturbative QCD (pQCD).…

General Physics · Physics 2019-06-11 Gouranga C Nayak

We review some of the recent developments in QCD spin physics and highlight the spin program now underway at RHIC.

High Energy Physics - Phenomenology · Physics 2008-11-26 Werner Vogelsang

It is shown that the proton "spin crisis'' or "spin puzzle" can be understood by the relativistic effect of quark transversal motions due to the Melosh-Wigner rotation. The quark helicity $\Delta q$ measured in polarized deep inelastic…

High Energy Physics - Phenomenology · Physics 2011-04-15 Bo-Qiang Ma

We derive the consequences of the Myhrer-Thomas explanation of the proton spin problem for the distribution of orbital angular momentum on the valence and sea quarks. After QCD evolution these results are found to be in very good agreement…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. W. Thomas

We study the covariant version of the quark-parton model, in which the general rules of the angular momentum composition are accurately taken into account. We demonstrate how these rules affect the relativistic interplay between the quark…

High Energy Physics - Phenomenology · Physics 2014-04-07 Petr Zavada

The "proton radius puzzle" remains unsolved since it was established in 2010. This paper summarizes the current state and gives an overview over upcoming experiments.

Nuclear Experiment · Physics 2014-11-17 Jan C. Bernauer