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Related papers: Nucleon Strangeness and Unitarity

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The nucleon strange vector and isoscalar electromagnetic form factors are studied using a spectral decomposition. The K\bar{K} contribution to the electric and magnetic radii as well as the magnetic moment is evaluated to all orders in the…

High Energy Physics - Phenomenology · Physics 2014-11-17 H. -W. Hammer , M. J. Ramsey-Musolf

We analyse the isoscalar vector current form factors of the nucleon using dispersion relations. In addition to the usual vector meson poles, we account for the K\bar{K}-continuum contribution by drawing upon a recent analytic continuation…

High Energy Physics - Phenomenology · Physics 2014-11-17 H. -W. Hammer , M. J. Ramsey-Musolf

We review a recent theoretical determination of the strange quark content of the electromagnetic form factors of the nucleon. These are compared with a global analysis of current experimental measurements in parity-violating electron…

Nuclear Theory · Physics 2008-11-26 Ross D. Young

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

The leading non-zero electric moment of the nucleon strange-quark vector current is the mean square strangeness radius, $<r_s^2>$. We evaluate the lightest OZI-allowed contribution to $<r_s^2>$, arising from the kaon cloud, using dispersion…

High Energy Physics - Phenomenology · Physics 2009-10-30 M. J. Ramsey-Musolf , H. -W. Hammer

The status of theoretical calculations of the strange quark vector current form factors of the nucleon is reviewed.

High Energy Physics - Phenomenology · Physics 2009-10-30 M. J. Ramsey-Musolf

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

Intrinsic strangeness contributions to low-energy strange quark matrix elements of the nucleon are modelled using kaon loops and meson-nucleon vertex functions taken from nucleon-nucleon and nucleon-hyperon scattering. A comparison with…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. J. Musolf , M. Burkardt

We discuss two descriptions of the nucleon's strange vector form factors in the framework of vector meson dominance. The first, an updated and extended version of Jaffe's dispersion analysis, approximates the spectral functions of the form…

High Energy Physics - Phenomenology · Physics 2009-10-28 Hilmar Forkel

The nucleon's strange-quark vector current form factors are studied from the perspective of chiral symmetry. It is argued that chiral perturbation theory cannot yield a prediction for the strangeness radius and magnetic moment. Arrival at…

Nuclear Theory · Physics 2009-09-25 M. J. Musolf , Hiroshi Ito

A remarkably successful program of parity-violating electron scattering experiments is providing new insight into the structure of the nucleon. Measurement of the vector form factors enables a definitive study of potential strange…

High Energy Physics - Phenomenology · Physics 2009-11-07 R. D. McKeown , M. J. Ramsey-Musolf

I review the results of a recent dispersion--theoretical analysis of the nucleon electromagnetic form factors and comment on the strangeness form factors. The need for a better data basis at low, intermediate and large momentum transfer is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ulf-G. Meißner

Measurement of the neutral weak vector form factors of the nucleon provides unique access to the strange quark content of the nucleon. These form factors can be studied using parity-violating electron scattering. A comprehensive program of…

Nuclear Experiment · Physics 2012-10-29 D. S. Armstrong , R. D. McKeown

Strange matrix elements of the nucleon are calculated within the light-cone formulation of the meson cloud model. The $Q^2$ dependence of the strange vector and axial vector form factors is computed, and the strangeness radius and magnetic…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. Melnitchouk , M. Malheiro

The strange form factors of the nucleon are studied in a two-component model consisting of a three-quark intrinsic structure surrounded by a meson cloud. A comparison with the available experimental world data from the SAMPLE, PVA4, HAPPEX…

Nuclear Theory · Physics 2008-11-26 R. Bijker

A model combining vector meson dominance, $\omega - \phi$ mixing and a kaon cloud contribution is used to estimate the strangeness vector form factors of the nucleon in the momentum range of the planned measurements at MIT-Bates and CEBAF.…

High Energy Physics - Phenomenology · Physics 2009-09-25 Hilmar Forkel , Marina Nielsen , Xuemin Jin , Thomas D. Cohen

I discuss how dispersion relations can be used to analyse the nucleon electromagnetic form factors, with particular emphasis on the constraints from unitarity and pQCD. Results for nucleon radii, vector-meson couplings, the onset of pQCD…

High Energy Physics - Phenomenology · Physics 2009-10-30 Ulf-G. Meißner

We analyze the nucleon matrix element of the strange quark vector current in a nucleon--model independent dispersive approach with input from the current world data set for the isoscalar electromagnetic form factors. The update of Jaffe's…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hilmar Forkel

A crucial input for recent meson hyperon cloud model estimates of the nucleon matrix element of the strangeness current are the nucleon-hyperon-K* (NYK*) form factors which regularize some of the arising loops. Prompted by new and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Hilmar Forkel , Fernando S. Navarra , Marina Nielsen

We use the meson cloud model, including the kaon and the $K^*$ contributions, to estimate the electric and magnetic strange form factors of the nucleon. We compare our results with the recent measurements of the strange quark contribution…

Nuclear Theory · Physics 2009-11-11 Fabiana Carvalho , Fernando S. Navarra , Marina Nielsen
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