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Related papers: Nucleon Axial and Electromagnetic Form Factors

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We calculate the electromagnetic pion form factor at intermediate space-like momentum transfer from the QCD sum rule for the correlation function of two {\it pseudoscalar } interpolating fields and the electromagnetic current. This…

High Energy Physics - Phenomenology · Physics 2009-10-28 Hilmar Forkel , Marina Nielsen

Measurements and theoretical calculations of meson form factors are essential for our understanding of internal hadron structure and QCD, the dynamics that bind the quarks in hadrons. The pion electromagnetic form factor has been measured…

High Energy Physics - Lattice · Physics 2018-04-18 Jonna Koponen , André Zimermmane-Santos , Christine Davies , G. Peter Lepage , Andrew Lytle

The electromagnetic form factors are the most fundamental quantities to describe the internal structure of the nucleon and the shape of a spatially extended particle is determined by its intrinsic quadrupole moment which can be related to…

High Energy Physics - Phenomenology · Physics 2015-05-18 Harleen Dahiya , Neetika Sharma

We present results on the isoscalar form factors including the disconnected contributions, as well as on the strange and charm quark form factors. Using previous results on the isovector form factors, we determine the flavor decomposition…

High Energy Physics - Lattice · Physics 2021-10-13 C. Alexandrou , S. Bacchio , M. Constantinou , K. Hadjiyiannakou , K. Jansen , G. Koutsou

We briefly report on results about the electromagnetic form factors of the nucleon obtained with different models and then we concentrate our attention on recent results obtained with the hypercentral constituent quark model (hCQM).

High Energy Physics - Phenomenology · Physics 2007-05-23 M. De Sanctis , M. M. Giannini , E. Santopinto , A. Vassallo

We study the ability of a variety of fitting techniques to extract the ground state matrix elements of the vector current from ratios of nucleon three- and two-point functions that contain contaminations from excited states. Extending our…

High Energy Physics - Lattice · Physics 2014-11-19 G. M. von Hippel , S. Capitani , D. Djukanovic , J. Hua , B. Jäger , P. Junnarkar , H. B. Meyer , T. D. Rae , H. Wittig

We report the calculation of electromagnetic form factors of nucleons within a relativistic three-quark model with Gaussian shape for the nucleon-quark vertex. The allowed region for two adjustable parameters, the range parameter…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. A. Ivanov , M. P. Locher , V. E. Lyubovitskij

We compute the electromagnetic form factor of the pion using non-perturbatively O(a) improved Wilson fermions. The calculations are done for a wide range of pion masses and lattice spacings. We check for finite size effects by repeating…

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

The electromagnetic form factors of the nucleon, in the space-like region, are determined from three-point function Finite Energy QCD Sum Rules. The QCD calculation is performed to leading order in perturbation theory in the chiral limit,…

High Energy Physics - Phenomenology · Physics 2009-11-10 H. Castillo , C. A. Dominguez , M. Loewe

We present an investigation of the electromagnetic pion form factor, $F_\pi(Q^2)$, at small values of the four-momentum transfer $Q^2$ ($\lesssim 0.25$ GeV$^2$), based on the gauge configurations generated by European Twisted Mass…

Dispersion relations allow for a coherent description of the nucleon electromagnetic form factors measured over a large range of momentum transfer, $Q^2 \simeq 0 \ldots 35$ GeV$^2$. Including constraints from unitarity and perturbative QCD,…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Mergell , Ulf-G. Meißner , D. Drechsel

We present a quenched lattice calculation of the weak nucleon form factors: vector (F_V(q^2)), induced tensor (F_T(q^2)), axial-vector (F_A(q^2)) and induced pseudo-scalar (F_P(q^2)) form factors. Our simulations are performed on three…

High Energy Physics - Lattice · Physics 2009-04-10 Shoichi Sasaki , Takeshi Yamazaki

We present results for Monte Carlo calculations of the electromagnetic vector and scalar form factors of the pion in a quenched simulation. We work at a lattice spacing of 0.15 fm and use two lattice volumes up to a spatial size of 2.4 fm.…

High Energy Physics - Lattice · Physics 2007-05-23 Stefano Capitani , Christof Gattringer , C. B. Lang

In-medium nucleon electromagnetic form factors are calculated in the quark meson coupling model. The form factors are typically found to be suppressed as the density increases. For example, at normal nuclear density and $Q^2 \sim 0.3 {…

Nuclear Theory · Physics 2008-11-26 D. H. Lu , A. W. Thomas , K. Tsushima , A. G. Williams , K. Saito

We calculate the nucleon axial form factor up to the leading one-loop order in a covariant chiral effective field theory with the $\Delta(1232)$ resonance as an explicit degree of freedom. We fit the axial form factor to the latest lattice…

High Energy Physics - Phenomenology · Physics 2018-02-08 De-Liang Yao , Luis Alvarez-Ruso , Manuel J. Vicente-Vacas

We present a comprehensive analysis of the spacelike nucleon electromagnetic form factors and their flavor decomposition within the framework of light-front holographic QCD. We show that the inclusion of the higher Fock components $\ket…

High Energy Physics - Phenomenology · Physics 2017-02-03 Raza Sabbir Sufian , Guy F. de Téramond , Stanley J. Brodsky , Alexandre Deur , Hans Günter Dosch

In this study, we employ a modified soft-wall holographic model with four flavors to investigate the meson spectra, decay constants, electromagnetic form factors, and charge radius of various mesons. We obtain the spectra for vector, axial…

High Energy Physics - Phenomenology · Physics 2023-08-30 Hiwa A. Ahmed , Yidian Chen , Mei Huang

A systematic calculation of nuclear matter is performed which includes the long-range correlations between nucleons arising from one- and two-pion exchange. Three-body effects from $2\pi$-exchange with excitations of virtual…

Nuclear Theory · Physics 2008-11-26 N. Kaiser , M. Mühlbauer , W. Weise

We compute the electromagnetic form factor of a "pion" with mass m_pi=330MeV at low values of Q^2\equiv -q^2, where q is the momentum transfer. The computations are performed in a lattice simulation using an ensemble of the RBC/UKQCD…

High Energy Physics - Lattice · Physics 2009-01-06 P. A. Boyle , J. M. Flynn , A. Juttner , C. Kelly , H. Pedroso de Lima , C. M. Maynard , C. T. Sachrajda , J. M. Zanotti