English
Related papers

Related papers: Nucleon Strangeness and Unitarity

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

The strangeness content of nucleon form factors is analyzed in a two-component model with a quark-like intrinsic structure surrounded by a meson cloud. A comparison with the available experimental data from the SAMPLE, PVA4, HAPPEX and G0…

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

Dispersion relations provide a powerful tool to describe the low-energy structure of hadrons. We review the status of the strange vector form factors of the nucleon in dispersion theory. We also comment on open questions and the relation to…

High Energy Physics - Phenomenology · Physics 2007-05-23 H. -W. Hammer

A formalism based on a relativistic plane wave impulse approximation is developed to investigate the strange-quark content ($g_{A}^{s}$) of the axial-vector form factor of the nucleon via neutrino-nucleus scattering. Nuclear structure…

Nuclear Theory · Physics 2008-11-26 B. I. S. van der Ventel , J. Piekarewicz

Starting from the $\omega$-$\phi$ mixing, further assuming the coupling of the quark-current of some flavour to be of universal strenth exclusively to the component of vector-meson wave function with the same flavour and finally taking…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Dubnicka , A. Z. Dubnickova

We investigate the strange electric and magnetic form factors of the nucleon in the framework of heavy baryon chiral perturbation theory to third order in the chiral expansion. All counterterms can be fixed from data. In particular, the two…

Nuclear Theory · Physics 2009-10-31 Thomas R. Hemmert , Bastian Kubis , Ulf-G. Meißner

We apply the perturbative chiral quark model at one loop to calculate the strange form factors of the nucleon. A detailed numerical analysis of the strange magnetic moments and radii of the nucleon, and also the momentum dependence of the…

High Energy Physics - Phenomenology · Physics 2009-11-07 V. E. Lyubovitskij , P. Wang , Th. Gutsche , Amand Faessler

The present status in the field of strange mesons in nuclei and neutron stars is reviewed. In particular, the $\bar K N$ interaction, that is governed by the presence of the $\Lambda(1405)$, is analyzed and the formation of the $\bar K NN$…

Nuclear Theory · Physics 2022-11-30 Laura Tolos

The recent investigation on various form factors of the nucleon is reviewed in the framework of the SU(3) chiral quark-soliton model. The results for the electromagnetic and scalar form factors are in remarkable agreement with experimental…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hyun-Chul Kim

We review the state of our knowledge concerning the contribution of strange quarks to various nucleon properties. In the case of the electric and magnetic form factors, the level of agreement between theory and experiment is very…

Nuclear Theory · Physics 2022-03-02 A. W. Thomas , P. E. Shanahan , R. D. Young

The role of the strange quarks on the low-energy interactions of the proton can be probed through the strange electromagnetic form factors. Knowledge of these form factors provides essential input for parity-violating processes and…

High Energy Physics - Lattice · Physics 2020-02-19 C. Alexandrou , S. Bacchio , M. Constantinou , J. Finkenrath , K. Hadjiyiannakou , K. Jansen , G. Koutsou

The recent parity-violating $ep$ forward-scattering elastic asymmetry data from Jefferson Lab (HAPPEx and G0), when combined with the $\nu p$ elastic cross section data from Brookhaven (E734), permit an extraction of the strangeness…

High Energy Physics - Experiment · Physics 2008-04-07 Stephen Pate

There are several different experimental indications, such as the strangeness contribution to the magnetic moment of the proton, sigma_{\pi N} term, strange spin polarization, ratio of strange and non strange quark flavor distributions…

High Energy Physics - Phenomenology · Physics 2008-11-26 Harleen Dahiya , Manmohan Gupta

Effective quark magnetic moments are extracted from experimental measurements as a function of the strangeness magnetic moment of the nucleon. Assumptions made in even the most general quark model analyses are ruled out by this…

Nuclear Theory · Physics 2009-10-28 Derek B. Leinweber

The strangeness contribution to the vector and axial form factors of the nucleon is presented for momentum transfers in the range $0.45<Q^2<1.0$ GeV$^2$. The results are obtained via a combined analysis of forward-scattering…

High Energy Physics - Experiment · Physics 2009-11-11 S. F. Pate , G. A. MacLachlan , D. W. McKee , V. Papavassiliou

Contributions from physics beyond the Standard Model, strange quarks in the nucleon, and nuclear structure effects to the left-right asymmetry measured in parity-violating (PV) electron scattering from $\nuc{12}{C}$ and the proton are…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. J. Musolf , T. W. Donnelly

Strange quark contributions to neutrino(antineutrino) scattering are investigated on the nucleon level in the quasi-elastic region. The incident energy range between 500 MeV and 1.0 GeV is used for the scattering. All of the physical…

Nuclear Theory · Physics 2008-11-26 Myung-Ki Cheoun , K. S. Kim

We review the area of strange quark contributions to nucleon structure. In particular, we focus on current models of strange quark vector currents in the nucleon and the associated parity-violating elastic electron scattering experiments…

High Energy Physics - Phenomenology · Physics 2016-12-21 D. H. Beck , B. R. Holstein

The calculation of the strangeness content of the nucleon and its experimental verification is a fundamental step in establishing non-perturbative QCD as the correct theory describing the structure of hadrons. It holds a role in QCD…

Nuclear Theory · Physics 2010-01-15 A. W. Thomas

We review the dispersion-theoretical analysis of the electromagnetic form factors of the nucleon. We emphasize in particular the role of unitarity and analyticity in the construction of the isoscalar and isovector spectral functions. We…

High Energy Physics - Phenomenology · Physics 2021-08-27 Yong-Hui Lin , Hans-Werner Hammer , Ulf-G. Meißner