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Related papers: The Proton-Spin Crisis: another ABJ anomaly?

200 papers

Contents (Part 1): 1.Derivation of Lorentz Invariance and Three Space Dimensions in Generic Field Theory (C D. Froggatt and H. B. Nielsen) 2.Unitary Representations, Noncompact Groups SO(q; d - q)...(N. Mankoc Borstnik, H. B. Nielsen and D.…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. Mankoc Borstnik , H. Bech Nielsen , C. D. Froggatt , D. Lukman , A. Borstnik Bracic , A. Kleppe , D. L. Bennett

A large set of data on proton-proton differential cross sections, analyzing powers and the double polarization parameter A_NN is analyzed employing the Regge formalism. We find that the data available at proton beam momenta from 3 GeV/c to…

High Energy Physics - Phenomenology · Physics 2014-11-20 A. Sibirtsev , J. Haidenbauer , H. -W. Hammer , S. Krewald , U. -G. Meißner

In deeply virtual exclusive electroproduction to leading order accuracy one accesses generalized parton distributions on their cross-over trajectory. Combining Lorentz covariance and analyticity leads to a family of GPD sum rules, guiding…

High Energy Physics - Phenomenology · Physics 2008-07-02 K. Kumericki , D. Mueller , K. Passek-Kumericki

The Minimal superstring unification, assuming orbifold compactification, provides interesting and rather detailed implications on physics at low energy. The interesting feature of this model is that the masses of the spectrum are related…

High Energy Physics - Phenomenology · Physics 2008-11-26 Shaaban Khalil

The data from the last seven experiments performed on polarized deep--inelastic scattering on proton and neutron (or deuteron) targets have been analyzed in search of a precise determination of the spin fraction carried by the quarks in the…

High Energy Physics - Phenomenology · Physics 2008-02-03 Paolo M. Gensini

Many experiments are underway in the world to search for a non-zero electric dipole moment (EDM) of a particle with spin 1/2 such as the neutron or the electron. Finding an EDM would reveal new sources of CP violation. EDM measurements are…

High Energy Physics - Phenomenology · Physics 2019-12-18 Guillaume Pignol

Different decompositions (sum rules) for the proton mass have been proposed in the literature. All of them are related to the energy-momentum tensor in quantum chromodynamics. We review and revisit these decompositions by paying special…

High Energy Physics - Phenomenology · Physics 2021-01-04 Andreas Metz , Barbara Pasquini , Simone Rodini

The target-independent suppression mechanism proposed as an explanation of the EMC-SMC `proton spin' effect is reviewed and compared to current experimental data. According to this proposal, the anomalous suppression observed in the first…

High Energy Physics - Phenomenology · Physics 2009-10-28 G. M. Shore

These are the commentaries for a volume of reprints of my selected papers with commentaries that I am preparing for publication by World Scientific. Contents: Preface; (1)Early Years, and Condensed Matter Physics; (2) High Energy Neutrino…

High Energy Physics - Phenomenology · Physics 2016-11-23 Stephen L. Adler

This talk reviews some of the hot topics in spin physics and related subjects, including perturbative QCD predictions for polarized parton distributions and their possible behaviours at small x, the Bjorken and singlet sum rules and the…

High Energy Physics - Phenomenology · Physics 2016-09-06 John Ellis

We provide a theoretical basis for understanding the spin structure of the proton in terms of the spin and orbital angular momenta of free quarks and gluons in Feynman's parton picture. We show that each term in the Jaffe-Manohar spin sum…

High Energy Physics - Phenomenology · Physics 2015-03-12 Xiangdong Ji , Jian-Hui Zhang , Yong Zhao

The review of current experimental situation in the measurements of the first moment $\Gamma_{p,n}$ of spin dependent nucleon structure functions $g_{1;p,n}(x,Q^2)$ is presented. The results of the calculations of twist-4 corrections to…

High Energy Physics - Phenomenology · Physics 2015-06-25 B. L. Ioffe

Since the announcement of the proton spin crisis by the European Muon Collaboration there has been considerable progress in unravelling the distribution of spin and orbital angular momentum within the proton. We review the current status of…

High Energy Physics - Phenomenology · Physics 2009-08-03 A. W. Thomas

We present predictions for the spin structure functions of the proton and the neutron in the framework of a unitary isobar model for one-pion photo- and electroproduction. Our results are compared with recent experimental data from SLAC.…

Nuclear Theory · Physics 2007-05-23 L. Tiator , D. Drechsel , S. S. Kamalov

Strange quark contributions to the proton magnetic moment are estimated from a consideration of baryon magnetic moment sum rules. The environment sensitivity of quark contributions to baryon moments is emphasized. Pion cloud contributions…

High Energy Physics - Phenomenology · Physics 2009-10-28 Derek B. Leinweber

In this lecture I review the present status of CP violation in the Standard Model and some of its extensions and discuss ways to distinguish different models. Contents 1. Introduction 2. CP violation in the Standard Model 3. Test the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xiao-Gang He

The QCD treatment of the photon structure is recalled. Emphasis is given to the recently derived momentum sum rule, and to the proper choice of the factorization scheme and/or boundary conditions for the evolution equations beyond the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andreas Vogt

This paper belongs to a series devoted to the calculation of particle masses in p-adic conformal field theory limit of TGD. In paper III elementary particle masses were calculated. In this paper the results are analyzed. One can reproduce…

High Energy Physics - Theory · Physics 2008-02-03 M. Pitkänen

The spin structure of nucleon at twist 2 and 3 levels is analyzed. The contribution of quark and gluon spins to nucleon spin are Lorentz invariant, while it is not sure for orbital angular momentum. The conserved fractional moments of…

High Energy Physics - Phenomenology · Physics 2007-05-23 O. Teryaev , B. Pire , J. Soffer

The gauge-invariant Chern-Simons-type Lorentz- and CPT-breaking term is here reassessed and a spin-projector method is adopted to account for the breaking (vector) parameter. Issues like causality, unitarity, spontaneous gauge-symmetry…

High Energy Physics - Theory · Physics 2009-11-07 A. P. Baeta Scarpelli , H. Belich , J. L. Boldo , J. A. Helayel-Neto