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Related papers: Nucleon resonances and transition form factors

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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

I present a survey of calculations of the excited $N^*$ spectrum in lattice QCD. I then describe recent advances aimed at extracting the momentum-dependent phase shifts from lattice calculations, notably in the meson sector, and the…

Nuclear Theory · Physics 2016-10-12 David Richards

The kaon electromagnetic (e.m.) form factor is reviewed considering a light-front constituent quark model. In this approach, it is discussed the relevance of the quark-antiquark pair terms for the full covariance of the e.m. current. It is…

High Energy Physics - Phenomenology · Physics 2009-11-13 Fabiano P. Pereira , J. P. B. C. de Melo , T. Frederico , Lauro Tomio

The second excitation of the nucleon, the Roper, has properties differentiated from other low-lying nucleon resonances. Their properties challenge our understanding of the structure of the baryons in terms of the degrees of freedom from…

High Energy Physics - Phenomenology · Physics 2026-02-12 G. Ramalho

We compute electromagnetic and two-photon transition form factors of ground-state pseudoscalar mesons: $\pi,\,K,\,\eta_c,\,\eta_b$. To this end, we employ an algebraic model based upon the coupled formalism of Schwinger-Dyson and…

High Energy Physics - Phenomenology · Physics 2024-07-10 I. M. Higuera-Angulo , R. J. Hernández-Pinto , K. Raya , A. Bashir

We give an update on our ongoing efforts to compute the nucleon's form factors and moments of structure functions using Nf=2 flavours of non-perturbatively improved Clover fermions. We focus on new results obtained on gauge configurations…

Accessing hadronic form factors at large momentum transfers has traditionally presented a challenge for lattice QCD simulations. Here we demonstrate how a novel implementation of the Feynman-Hellmann method can be employed to calculate…

The electromagnetic form factors provide important insight into the internal structure of the nucleon and continue to be of major interest for experiment and phenomenology. For an intermediate range of momenta the form factors can be…

We discuss electromagnetic currents in the point-form formulation of relativistic quantum mechanics. The construction is along a spectator model and implies that only one quark is explicitly coupled to the photon, but nevertheless many-body…

Nuclear Theory · Physics 2017-08-23 T. Melde

Authors of Phys. Rev. C 60, 062201 (1999) presented a calculation of the electromagnetic form factors of the nucleon using a diquark ansatz in the relativistic three-quark Faddeev equations. In this Comment it is pointed out that the…

Nuclear Theory · Physics 2009-10-31 B. Blankleider , A. N. Kvinikhidze

Status, open questions, and future prospects of the physics of excited nucleons are discussed. Emphasis is on the study of the structure of nucleons via measurements of their electromagnetic transition form factors, the search for "missing"…

Nuclear Theory · Physics 2009-09-25 Volker D. Burkert

Backward elastic electron scattering from odd-A nuclear targets is characterized by magnetic form factors containing precise information on the nuclear structure. We study the sensitivity of the magnetic form factors to structural effects…

Nuclear Theory · Physics 2021-01-13 B. Hernandez , P. Sarriguren , O. Moreno , E. Moya de Guerra , D. N. Kadrev , A. N. Antonov

We review recent progress in our understanding of the nucleon excitation spectrum. Thanks to dedicated efforts at facilities such as ELSA, MAMI and Jefferson Lab, several new nucleon resonances have been discovered, and evidence for…

High Energy Physics - Phenomenology · Physics 2025-11-18 Volker Burkert , Gernot Eichmann , Eberhard Klempt

Nucleon form factors have been extensively studied both experimentally and theoretically for many years. We report here on new results of a high statistics quenched lattice QCD calculation of vector and axial-vector nucleon form factors at…

High Energy Physics - Lattice · Physics 2008-11-26 S. Capitani , M. Gockeler , R. Horsley , B. Klaus , H. Oelrich , H. Perlt , D. Petters , D. Pleiter , P. E. L. Rakow , G. Schierholz , A. Schiller , P. Stephenson

We investigate the electromagnetic form factors of the nucleon in the framework of basis light front quantization. We compute the form factors using the light front wavefunctions obtained by diagonalizing the effective Hamiltonian…

High Energy Physics - Phenomenology · Physics 2020-01-20 Chandan Mondal , Siqi Xu , Jiangshan Lan , Xingbo Zhao , Yang Li , Henry Lamm , James P. Vary

The deuteron form factors are calculated in the framework of the relativistic nucleon-meson dynamics, by means of the explicitly covariant light-front approach. The inflluence of the nucleon electromagnetic form factors is discussed. At…

Nuclear Theory · Physics 2014-11-18 J. Carbonell , V. A. Karmanov

We demonstrate that a relativistic constituent quark model can give nucleon form factors that agree well with recent, accurate measurements. The relativistic features of the model and the specific form of the wave function are essential for…

High Energy Physics - Phenomenology · Physics 2009-09-25 Felix Schlumpf

We compare a recent lattice determination of the nucleon distribution amplitudes with other approaches and models. We study the nucleon distribution amplitudes up to twist 6 in next-to leading conformal spin and we also investigate…

High Energy Physics - Phenomenology · Physics 2009-07-30 Alexander Lenz , Meinulf Göckeler , Thomas Kaltenbrunner , Nikolaus Warkentin

Studies of the nucleon resonance electroexcitation amplitudes in a wide range of photon virtualities offer unique information on many facets of strong QCD behind the generation of all prominent excited nucleon states. Advances in the…

Nuclear Experiment · Physics 2022-10-19 Victor I. Mokeev

The nucleon elastic form factors are generally interpreted as a mapping of the charge and magnetic current distributions of the proton and neutron. New high Q^2 measurements have opened up fundamental questions about G_ep that remain to be…

High Energy Physics - Experiment · Physics 2009-06-02 R. Bradford , A. Bodek , H. Budd , J. Arrington
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