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Related papers: Strange chiral nucleon form factors

200 papers

We discuss techniques for evaluating sea quark contributions to hadronic form factors on the lattice and apply these to an exploratory calculation of the strange electromagnetic, axial, and scalar form factors of the nucleon. We employ the…

High Energy Physics - Lattice · Physics 2012-05-23 Ronald Babich , Richard C. Brower , Michael A. Clark , George T. Fleming , James C. Osborn , Claudio Rebbi , David Schaich

We study meson-baryon scattering with strangeness -1 in unitary chiral perturbation theory. Ten coupled channels are considered in our work, namely $\pi^0 \Lambda$, $\pi^0 \Sigma^0$, $\pi^- \Sigma^+$, $\pi^+ \Sigma^-$, $K^- p$, $\bar{K}^0…

High Energy Physics - Phenomenology · Physics 2013-11-15 Zhi-Hui Guo , J. A. Oller

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 investigate the flavour decomposition of the electromagnetic form factors of the nucleon, based on the chiral quark-soliton model ($\chi$QSM) with symmetry-conserving quantisation. We consider the rotational $1/N_c$ and linear…

High Energy Physics - Phenomenology · Physics 2018-02-13 Antonio Silva , Diana Urbano , Hyun-Chul Kim

In order to isolate the contribution of the nucleon strange electric form factor to the parity-violating asymmetry measured in 4He(\vec e,e')4He experiments, it is crucial to have a reliable estimate of the magnitude of…

Nuclear Theory · Physics 2008-11-26 M. Viviani , R. Schiavilla , B. Kubis , R. Lewis , L. Girlanda , A. Kievsky , L. E. Marcucci , S. Rosati

We consider the spin-averaged nucleon forward Compton scattering amplitude in heavy baryon chiral perturbation theory including all terms to order ${\cal O} (q^4)$. The chiral prediction for the spin-averaged forward Compton scattering…

High Energy Physics - Phenomenology · Physics 2015-06-25 V. Bernard , N. Kaiser , Ulf-G. Meißner , A. Schmidt

We study chiral models with SU(3) group structure such as Skyrmion and chiral bag to yield theoretical predictions of proton strange form factor comparable to the recent experimental data of the SAMPLE Collaboration. For these predictions…

High Energy Physics - Phenomenology · Physics 2007-05-23 Soon-Tae Hong

I review recent progress made in the description of pion-nucleon scattering, the $\sigma$--term, the scalar form factor and the strangeness content of the nucleon in the framework of heavy baryon chiral perturbation theory. Other topics are…

High Energy Physics - Phenomenology · Physics 2011-04-15 Ulf-G. Meißner

We present the experimental status of electromagnetic hadron form factors. New and surprising results, based on polarization measurements, have been recently obtained for the electric proton and neutron form factors. In particular, the…

High Energy Physics - Phenomenology · Physics 2015-06-25 Egle Tomasi-Gustafsson

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 basic facts of charge symmetry breaking (CSB) phenomena are reviewed. The relevance of CSB to parity-violating electron-proton scattering experiments that seek to extract strange elastic form factors is discussed. Experimentalists have…

Nuclear Theory · Physics 2014-11-03 Gerald A. Miller

The electromagnetic form factors have attracted lot of theoretical and experimental attention recently as they encode extensive information on the internal structure of the hadron. An understanding of the form factors is necessary to…

High Energy Physics - Phenomenology · Physics 2011-08-02 Harleen Dahiya , Neetika Sharma

Scalar matrix elements involving strange quarks are studied in several models. Apart from a critical reexamination of results obtained in the Nambu and Jona-Lasinio model we study a scenario, motivated by instanton physics, where…

High Energy Physics - Phenomenology · Physics 2009-10-28 K. Steininger , W. Weise

The fine structure of the low energy part of the nucleon and strange hyperon spectra, which are formed of single states without parity doublets, may be understood in terms of an $SU(3)$ flavor-symmetric quark-quark interaction that…

High Energy Physics - Phenomenology · Physics 2011-04-20 L. Ya. Glozman , D. O. Riska

We determine the nucleon electromagnetic form factors and their uncertainties from world electron scattering data. The analysis incorporates two-photon exchange corrections, constraints on the low-Q2 and high-Q2 behavior, and additional…

Nuclear Experiment · Physics 2017-12-12 Zhihong Ye , John Arrington , Richard J. Hill , Gabriel Lee

Fascinating aspects of the light quark-mass behavior of baryon electromagnetic form factors are highlighted. Using FLIC fermions on $20^3 \times 40$ quenched ${\cal O}(a^2)$-improved gauge fields, we explore charge radii and magnetic…

High Energy Physics - Lattice · Physics 2010-03-04 J. N. Hedditch , B. G. Lasscock , D. B. Leinweber , A. G. Williams , J. M. Zanotti , J. B. Zhang

We investigated the form factors of the nucleon associated with the nonet vector current in the framework of the generalized Yabu--Ando approach to the chiral soliton of the Nambu--Jona--Lasinio model. We introduce a variational parameter…

High Energy Physics - Phenomenology · Physics 2007-05-23 Abdellatif Abada , H. Weigel , R. Alkofer , H. Reinhardt

In the chirally symmetric Nambu--Jona-Lasinio model baryons are described as chiral solitons of mesonic quark--antiquark bound states. Hyperons are investigated in two complementary pictures: the bound state approach of Callan and Klebanov…

High Energy Physics - Phenomenology · Physics 2011-04-20 R. Alkofer , H. Weigel , H. Reinhardt , A. Abada

The chiral quark model posits pseudoscalar and vector meson couplings to constituent quarks. The parity violating meson-quark couplings lead to anapole moments and form factors of the nucleons. These arise both as parity violating meson…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. O. Riska

We present results for the strange contribution to the electromagnetic form factors of the nucleon computed on the CLS ensembles with $N_f=2+1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an $\mathcal{O}(a)$-improved vector…

High Energy Physics - Lattice · Physics 2019-12-10 Dalibor Djukanovic , Konstantin Ottnad , Jonas Wilhelm , Hartmut Wittig