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Related papers: A Covariant model for the nucleon and the $\Delta$

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The $\gamma^\ast \gamma \to \pi^0$ transition form factor, $G(Q^2)$, is computed on the entire domain of spacelike momenta using a continuum approach to the two valence-body bound-state problem in relativistic quantum field theory: the…

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

On the received coefficients of the analytical forms for deuteron wave function in coordinate representation in form r^(l+1)*exp(-A*r) for the modern realistic nucleon-nucleon potentials NijmI, NijmII, Nijm93, Reid93 and Argonne v18 are…

Nuclear Theory · Physics 2019-07-15 V. I. Zhaba

Once chosen the dynamics in one frame, for example the rest frame, the Bakamjian and Thomas method allows to define relativistic quark models in any frame. These models have been shown to provide, in the heavy quark limit, fully covariant…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. Morénas , A. Le Yaouanc , L. Oliver , O. Pène , J. -C. Raynal

The structure of the nucleon and the first radial excitation of the nucleon, the Roper, $N(1440)$, is studied within the formalism of Light-Front holography. The nucleon elastic form factors and $\gamma^\ast N \to N(1440)$ transition form…

High Energy Physics - Phenomenology · Physics 2018-03-07 G. Ramalho , D. Melnikov

A recently developed formulation for treating two- and three-nucleon bound states in a three-dimensional formulation based on spin-momentum operators is extended to nucleon-nucleon scattering. Here the nucleon-nucleon t-matrix is…

Nucleon and pion electromagnetic form factors are evaluated in the spacelike region within a light-front constituent quark model, where eigenfunctions of a mass operator, reproducing a large set of hadron energy levels, are adopted and…

Nuclear Theory · Physics 2009-10-28 F. Cardarelli , E. Pace , G. Salme' , S. Simula

The recent investigation on various form factors of the nucleon is reviewed in the framework of the SU(3) chiral quark-soliton model. The results for the electromagnetic and scalar form factors are in remarkable agreement with experimental…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hyun-Chul Kim

Background The intense current experimental interest in studying the structure of the deuteron and using it to enable accurate studies of neutron structure motivate us to examine the four-dimensional space-time nature of the nuclear wave…

Nuclear Theory · Physics 2016-07-27 John D. Terry , Gerald A. Miller

The recent unbiased measurements of the electric form factor of the neutron suggest that its shape may be interpreted as a smooth broad distribution with a bump at Q^2 \approx 0.3(GeV/c)^2 superimposed. As a consequence the corresponding…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Friedrich , Th. Walcher

The pion electromagnetic form factor at spacelike momentum transfer is calculated in relativistic impulse approximation using the Covariant Spectator Theory. The same dressed quark mass function and the equation for the pion bound-state…

High Energy Physics - Phenomenology · Physics 2014-01-09 Elmar P. Biernat , Franz Gross , M. T. Peña , Alfred Stadler

We calculate the nucleon resonance contributions to nucleon Compton scattering, including all states with J^P = 1/2^{+-} and J^P = 3/2^{+-} where experimental data for their electromagnetic transition form factors exist. To this end, we…

High Energy Physics - Phenomenology · Physics 2018-12-05 Gernot Eichmann , G. Ramalho

We present in the article the formulation of a version of Lorentz covariant quantum mechanics based on a group theoretical construction from a Heisenberg-Weyl symmetry with position and momentum operators transforming as Minkowski…

General Physics · Physics 2020-02-18 Suzana Bedić , Otto C. W. Kong , Hock King Ting

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 investigate three different axial-vector form factors of the nucleon, $G_A^{0}$, $G_A^3$, $G_A^8$, within the framework of the SU(3) chiral quark-soliton model, emphasizing their strangeness content. We take into account the rotational…

High Energy Physics - Phenomenology · Physics 2016-09-06 Antonio Silva , Hyun-CHul Kim , Diana Urbano , Klaus Goeke

Recently, a relativistic chiral nucleon-nucleon interaction is formulated up to leading order which provides a good description of the phase shifts of $J\leq1$ partial waves [Chin. Phys. C 42 (2018) 014103]. Nevertheless, a separable…

Nuclear Theory · Physics 2021-06-09 Xiu-Lei Ren , Chun-Xuan Wang , Kai-Wen Li , Li-Sheng Geng , Jie Meng

The electromagnetic and gravitational form factors of $\Omega^-$, a spin-3/2 hyperon composed of three $s$ quarks, are calculated by using a covariant quark-diquark approach. The model parameters are determined by fitting to the form…

High Energy Physics - Phenomenology · Physics 2023-06-21 Dongyan Fu , JiaQi Wang , Yubing Dong

A Poincare' covariant Faddeev equation, which describes baryons as composites of confined-quarks and -nonpointlike-diquarks, is solved to obtain masses and Faddeev amplitudes for the nucleon and Delta. The amplitudes are a component of a…

Nuclear Theory · Physics 2010-03-04 R. Alkofer , A. Hoell , M. Kloker , A. Krassnigg , C. D. Roberts

The electromagnetic inclusive responses of polarized $^{3}$He and $^{3}$H are thoroughly investigated at the quasielastic peak for squared momentum transfers up to $2 (GeV/c)^2$, within the plane wave impulse approximation. Great emphasys…

Nuclear Theory · Physics 2008-11-26 A. Kievsky , E. Pace , G. Salme` , M. Viviani

Relativistic, kinematically complete phenomenological expressions for the dilepton decay rates of nucleon resonances with arbitrary spin and parity are derived in terms of the magnetic, electric, and Coulomb transition form factors. The…

Nuclear Theory · Physics 2011-08-17 M. I. Krivoruchenko , B. V. Martemyanov , Amand Faessler , C. Fuchs