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Related papers: Nucleon resonances in Compton scattering

200 papers

We propose possible methods to measure the nucleon electromagnetic form factors in presence of two-photon exchange. Using a general parametrization of the spin structure of the matrix element for elastic $eN$-scattering, in terms of three…

Nuclear Theory · Physics 2009-11-10 M. P. Rekalo , E. Tomasi-Gustafsson

The reaction of the elastic electron-deuteron scattering at high momentum transfer is investigated within the Bethe-Salpeter approach. The relativistic covariant Graz II separable kernel of nucleon-nucleon interactions is used to analyze…

Nuclear Theory · Physics 2015-06-19 A. V. Bekzhanov , S. G. Bondarenko , V. V. Burov

Organic charge transfer salts show a variety of complex phases ranging from antiferromagnetic long-range order, spin liquid, bad metal or even superconductivity. A powerful method to investigate magnetism is spin-polarized inelastic neutron…

Materials Science · Physics 2014-07-29 Francesc Salvat-Pujol , Harald O. Jeschke , Roser Valenti

We calculate the electromagnetic and the axial form factors of the nucleon within the framework of light cone sum rules (LCSR) to leading order in QCD and including higher twist corrections. In particular we motivate a certain choice for…

High Energy Physics - Phenomenology · Physics 2009-11-11 V. M. Braun , A. Lenz , M. Wittmann

We obtain the electromagnetic form factors of the $\gamma N\Delta$ transition by analyzing recent pion-electroproduction data using a fully relativistic dynamical model. Special care is taken to satisfy Ward-Takahashi identities for the…

Nuclear Theory · Physics 2010-01-18 G. L. Caia , V. Pascalutsa , J. A. Tjon , L. E. Wright

The inclusion of two-body exchange currents in the constituent quark model leads to several new relations between the electromagnetic form factors of the nucleon and Delta(1232). These are:(i) the neutron charge form factor can be expressed…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. J. Buchmann

We analyze the nucleon's Compton scattering amplitude in the Dyson-Schwinger/Faddeev approach. We calculate a subset of diagrams that implements the nonperturbative handbag contribution as well as all t-channel resonances. At the quark…

High Energy Physics - Phenomenology · Physics 2013-03-14 Gernot Eichmann , Christian S. Fischer

Results for the proton and neutron electric and magnetic form factors as well as the nucleon axial form factor are presented for constituent quark models, based on either one-gluon-exchange and Goldstone-boson-exchange dynamics. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. F. Wagenbrunn , S. Boffi , L. Ya. Glozman , W. Klink , W. Plessas , M. Radici

We study the effects of off-shellness in the generalized parton distributions of the pion. On general grounds, these distributions exhibit a richer structure than in the on-shell case due to absence of the crossing symmetry. In particular,…

High Energy Physics - Phenomenology · Physics 2023-11-21 Vanamali Shastry , Wojciech Broniowski , Enrique Ruiz Arriola

These proceedings sketch how combining recent theoretical advances with data from the new generation of high-precision Compton scattering experiments on both the proton and few-nucleon systems offers fresh, detailed insight into the Physics…

Nuclear Theory · Physics 2009-11-10 Harald W. Griesshammer

The Dressed K-matrix Model, developed previously for low- and intermediate-energy Compton scattering, is generalized to calculate the photon-nucleon vertex with a virtual photon and an off-shell nucleon. Using this model, the ratio of the…

Nuclear Theory · Physics 2009-11-10 S. Kondratyuk , K. Kubodera , F. Myhrer

We present calculations of $\gamma^\ast N \to N^\ast$ transition form factors, where $N$ is the nucleon and $N^\ast$ is a nucleon resonance, based on a covariant quark model. Our main focus is at high photon virtualities (large $Q^2$) where…

High Energy Physics - Phenomenology · Physics 2020-09-25 G. Ramalho

Dispersion relations provide a powerful tool to describe the electromagnetic form factors of the nucleon both in the spacelike and timelike regions with constraints from unitarity and perturbative QCD. We give a brief introduction into…

High Energy Physics - Phenomenology · Physics 2014-11-17 H. -W. Hammer

We study the deeply-virtual Compton scattering (DVCS) process $e^- N \to e^- \gamma \pi N$ involving the transition between a nucleon and a nucleon resonance in the $\pi N$ system, within the framework of generalized parton distributions…

High Energy Physics - Phenomenology · Physics 2023-03-02 Kirill M. Semenov-Tian-Shansky , Marc Vanderhaeghen

We use the energy-momentum tensor (EMT) current to compute the EMT form factors of the nucleon in the framework of the light cone QCD sum rule formalism. In the calculations, we employ the most general form of the nucleon's interpolating…

High Energy Physics - Phenomenology · Physics 2020-03-18 K. Azizi , U. Ozdem

The electromagnetic polarizabilities of the nucleon are fundamental properties that describe its response to external electric and magnetic fields. They can be extracted from Compton-scattering data --- and have been, with good accuracy, in…

Compton scattering provides important insight into the structure of the nucleon. For photons up to about 300 MeV, it is parameterised by six dynamical dipole polarisabilities which characterise the response of the nucleon to a monochromatic…

Nuclear Theory · Physics 2012-12-12 Harald W. Griesshammer , Judith A. McGovern , Daniel R. Phillips , Gerald Feldman

We argue that at moderately large momentum transfer -t <10 GeV^2, hadronic form factors and wide-angle Compton scattering amplitudes are dominated by mechanism corresponding to overlap of soft wave functions. We show that the soft…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. V. Radyushkin

The study of electromagnetic and weak form factors of nucleon (charged quasielastic scatterings of neutrino (antineutrino) and nucleon) done in $70^\prime s$ and published in Chinese journals is reviewed. In the approach of the study…

High Energy Physics - Phenomenology · Physics 2014-11-25 Bing An Li

In treating the relativistic three-quark problem, a dressed-quark propagator parameterization is used which is compatible with recent lattice data and pion observables. Furthermore two-quark correlations are modeled as a series of quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Oettel , R. Alkofer