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Related papers: Nucleon Form Factors in Dispersion Theory

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This talk presents an introduction to the use of dispersion relations to constrain the shapes of hadronic form factors consistent with QCD. The applications described include methods for studying |V_{cb}| and |V_{ub}|, the strange quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 Richard F. Lebed

Precise proton and neutron form factor measurements at Jefferson Lab, using spin observables, have recently made a significant contribution to the unraveling of the internal structure of the nucleon. Accurate experimental measurements of…

Nuclear Experiment · Physics 2015-06-02 V. Punjabi , C. F. Perdrisat , M. K. Jones , E. J. Brash , C. E. Carlson

I summarize the dispersion-theoretical analysis of the nucleon electromagnetic form factors. Special emphasis is given on the extraction of the proton charge radius and its relatives, the proton magnetic radius as well as the neutron…

High Energy Physics - Phenomenology · Physics 2022-11-11 Ulf-G. Meißner

We provide a complete calculation of all leading nucleon form factors at large momentum transfer and in single gauge boson exchange approximation. In order to evaluate the required nucleon transition probability matrix elements, we combine…

High Energy Physics - Phenomenology · Physics 2011-11-04 Thorsten Sachs , Patrick Sturm

We present a detailed study of the nucleon electromagnetic form factors in the spacelike region by combining three complementary approaches: two GPD-based contributions and a vector-meson exchange component. By fitting experimental data, we…

High Energy Physics - Phenomenology · Physics 2026-04-13 Hossein Vaziri , Mohammad Reza Shojaei , Pere Masjuan

Several aspects of hadron physics are well described by a simple 5D effective field theory. Baryons arise in this scenario as "large" (and therefore calculable) 5D skyrmions. We extend and refine the existing analysis of this 5D soliton,…

High Energy Physics - Phenomenology · Physics 2010-04-15 Giuliano Panico , Andrea Wulzer

The strange-quark vector current form factors of the nucleon are analyzed within the framework of dispersion relations. Particular attention is paid to contributions made by $K\bar{K}$ intermediate states to the form factor spectral…

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

In this work, we employ a dispersion relation that allows to recover the electromagnetic form factor of the pion from its modulus along the unitarity cut. Unlike the standard dispersive approach, this method extends in a straightforward…

High Energy Physics - Phenomenology · Physics 2024-10-24 Pablo Sanchez-Puertas , Enrique Ruiz Arriola

This talk presents issues pertaining to the quark structure of the pion within QCD, both from the theoretical and from the experimental point of view. We review and discuss the pion-photon transition form factor and the pion's…

High Energy Physics - Phenomenology · Physics 2008-11-07 N. G. Stefanis

Form factors are Lorentz invariant functions describing the internal structure of a system. In particular, they encode how physical properties like, e.g., charge, energy, momentum, and pressure are spatially distributed. While nucleon…

High Energy Physics - Phenomenology · Physics 2024-02-02 Cédric Lorcé

A review of data on the nucleon electromagnetic form factors in the space-like region is presented. Recent results from experiments using polarized beams and polarized targets or nucleon recoil polarimeters have yielded a significant…

High Energy Physics - Experiment · Physics 2010-11-03 Kees de Jager

Using the framework of generalized parton distribution, we provide a unified interpretation of the connected and disconnected contributions from the ab-initio Euclidean path-integral formulation of the hadronic tensor in both the nucleon…

High Energy Physics - Phenomenology · Physics 2025-12-25 Zaki Panjsheeri , Saraswati Pandey , Brannon Semp , Simonetta Liuti

These lectures give an introduction to the structure of the nucleon as seen with the electromagnetic probe. Particular emphasis is put on the form factors, the strangeness content, Compton scattering and polarizabilities, pion photo- and…

Nuclear Theory · Physics 2017-08-23 D. Drechsel

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

The first three coefficients of the Taylor's series expansion of the vector pion form factor as a function of the momentum transfer are evaluated using experimental data on the pion form factor and the P-wave pi pi phase shifts. The real…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tran N. Truong

We compute the electromagnetic form factors of the nucleon in the Poincare-covariant Faddeev framework based on the Dyson-Schwinger equations of QCD. The general expression for a baryon's electromagnetic current in terms of three…

High Energy Physics - Phenomenology · Physics 2011-08-08 Gernot Eichmann

We compute the electromagnetic form factors of the nucleon in quenched lattice QCD, using non-perturbatively improved Wilson fermions, and compare the results with phenomenology and chiral effective field theory.

High Energy Physics - Lattice · Physics 2010-04-06 M. Göckeler , T. R. Hemmert , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz

We present a unified description of elastic and transition form factors involving the nucleon and its resonances; in particular, the $N(1440)$, $\Delta(1232)$ and $\Delta(1600)$. We compare predictions made using a framework built upon a…

Nuclear Theory · Physics 2020-08-26 J. Segovia , C. Chen , Z. -F. Cui , Y. Lu , C. D. Roberts

The electromagnetic form factors of the $\Lambda$ hyperon in the time-like region are determined precisely through a dispersion-theoretical analysis of the world data for the cross section of the annihilation process $e^+e^-\to…

High Energy Physics - Phenomenology · Physics 2022-12-21 Yong-Hui Lin , Hans-Werner Hammer , Ulf-G. Meißner

The roles played by mesons in the electromagnetic form factors of the nucleon are explored using as a basis a model containing vector mesons with coupling to the continuum together with the asymptotic $Q^2$ behavior of perturbative QCD.…