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Related papers: Nucleon strangeness and spin crisis?

200 papers

The simplest models might describe the nucleon as 3 light quarks, but this description would be incomplete without inclusion of the sea of glue and q-qbar pairs which binds it. Early indications of a particularly large contribution from…

Nuclear Experiment · Physics 2011-10-18 Kent Paschke , Anthony Thomas , Robert Michaels , David Armstrong

It is shown that in both the gluonic and strange sea explanations of the Ellis-Jaffe sum rule violation discovered by the European Muon Collaboration (EMC), the spin of the proton, when viewed in in its rest reference frame, could by fully…

High Energy Physics - Phenomenology · Physics 2009-10-22 Bo-Qiang Ma , Qi-Ren Zhang

We decompose various quark-gluon Fock states of a nucleon in a set of states in which each of the three-quark core and the rest of the stuff, termed as a sea, appears with definite spin and color quantum number, their weight being…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. P. Singh , Alka Upadhyay

A simple calculation in the framework of the chiral quark theory of Manohar and Georgi yields results that can account for many of the ''failures'' of the naive quark model: significant strange quark content in the nucleon as indicated by…

High Energy Physics - Phenomenology · Physics 2009-09-25 T. P. Cheng , Ling-Fong Li

A brief summary of strangeness mile stones is followed by a chemical non-equilibrium statistical hadronization analysis of strangeness results at SPS and RHIC. Strange particle production in AA interactions at \sqrt{s_{NN}}\ge 8.6 GeV can…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. Rafelski , J. Letessier

We derive light-cone sum rules for the electromagnetic nucleon form factors including the next-to-leading-order corrections for the contribution of twist-three and twist-four operators and a consistent treatment of the nucleon mass…

High Energy Physics - Phenomenology · Physics 2013-12-16 I. V. Anikin , V. M. Braun , N. Offen

QCD sum rules for the nucleon are considered in complex q^2 plane with inclusion of the radiative corrections of the order alpha_s. It is shown that the radiative corrections affect mainly the residue lambda^2 of the nucleon pole. Their…

High Energy Physics - Phenomenology · Physics 2009-11-11 V. A. Sadovnikova , E. G. Drukarev , M. G. Ryskin

The strangeness magnetic moment of the proton is shown to be small in the chiral quark model. The dominant loop contribution is due to kaons. The K^* loop contributions are proportional to the difference between the strange and light…

High Energy Physics - Phenomenology · Physics 2011-08-11 L. Hannelius , D. O. Riska , L. Ya. Glozman

We study the important, yet widely overlooked, role of gluons for spin transport with a connection to local parity violation in quark gluon plasmas. We employ the formalism of quantum kinetic theory to quarks in weakly coupled quantum…

Nuclear Theory · Physics 2022-09-27 Berndt Müller , Di-Lun Yang

We discuss the phenomenology of strange-quark dynamics in the nucleon, based on experimental and theoretical results for electroweak form factors and for parton densities. In particular, we construct a model for the generalized parton…

High Energy Physics - Phenomenology · Physics 2025-01-22 M. Diehl , Th. Feldmann , P. Kroll

On top of its valence quarks, the full nucleon ground state may contain appreciable admixture of s-\bar{s} pairs already at small momentum transfers. This paper discusses strangeness in the mean-field type of nucleon models, and exemplifies…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Klabucar , K. Kumericki , B. Melic , I. Picek

We evaluate the gluon and quark contributions to the spin of the proton using an ensemble of gauge configuration generated at physical pion mass. We compute all valence and sea quark contributions to high accuracy. We perform a…

High Energy Physics - Lattice · Physics 2020-08-26 C. Alexandrou , S. Bacchio , M. Constantinou , J. Finkenrath , K. Hadjiyiannakou , K. Jansen , G. Koutsou , H. Panagopoulos , G. Spanoudes

Data on the mean multiplicity of strange hadrons produced in minimum bias proton--proton and central nucleus--nucleus collisions at momenta between 2.8 and 400 GeV/c per nucleon have been compiled. The multiplicities for nucleon--nucleon…

High Energy Physics - Experiment · Physics 2009-10-28 Marek Gazdzicki , Dieter Roehrich

We study contributions to the nucleon strange quark vector current form factors from intermediate states containing K^* mesons. We show how these contributions may be comparable in magnitude to those made by K mesons, using methods…

High Energy Physics - Phenomenology · Physics 2009-10-31 L. L. Barz , H. Forkel , H. -W. Hammer , F. S. Navarra , M. Nielsen , M. J. Ramsey-Musolf

After the EMC and subsequent experiments at CERN, SLAC and DESY on the deep inelastic scattering of polarized leptons on polarized nucleons, it is now established that the Q^2=0 value of the axial strange form factor of the nucleon, a…

High Energy Physics - Phenomenology · Physics 2009-11-07 W. M. Alberico , S. M. Bilenky , C. Maieron

The chiral constituent quark model ($\chi$CQM) has been extended to calculate the flavor structure of the nucleon through the meson-nucleon sigma terms which have large contributions from the quark sea and are greatly affected by chiral…

High Energy Physics - Phenomenology · Physics 2015-05-28 Harleen Dahiya , Neetika Sharma

The mass spectra of nucleon resonances with spin 1/2, 3/2, and 5/2 are systematically studied in the constituent quark model with meson-quark coupling, which is inspired by the spontaneous breaking of chiral symmetry of QCD. The meson-quark…

Nuclear Theory · Physics 2009-10-30 H. Kowata , M. Arima , K. Masutani

A dominant QCD mechanism for the single transverse-spin asymmetry in hard processes is induced by the twist-3 quark-gluon correlations inside nucleon, combined with the soft-gluonic poles to produce the interfering phase for the associated…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yuji Koike , Kazuhiro Tanaka

A theoretical prediction is given for the spin and orbital angular momentum distribution functions of the nucleon within the framework of an effective quark model of QCD, i.e. the chiral quark soliton model. An outstanding feature of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Wakamatsu , T. Watabe

We present the strange electromagnetic form factors of the nucleon using lattice QCD simulations with degenerate light, a strange, and a charm quark in the sea with masses tuned to their physical values. For the first time, the strange…