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Related papers: Large-$N_c$ relations for the electromagnetic N to…

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We review the description of the lowest-energy nucleon excitation -- the $\Delta$(1232)-resonance. Much of the recent experimental effort has been focused on the precision measurements of the nucleon-to-$\Delta$ transition by means of…

High Energy Physics - Phenomenology · Physics 2008-11-26 Vladimir Pascalutsa , Marc Vanderhaeghen , Shin Nan Yang

We obtain relations between partial-wave amplitudes for pi-N-->pi-N and pi-N-->pi-Delta directly from large N_c QCD. While linear relations among certain amplitudes holding at leading order (LO) in 1/N_c were derived in the context of…

High Energy Physics - Phenomenology · Physics 2009-11-10 Thomas D. Cohen , Daniel C. Dakin , Richard F. Lebed , Abhinav Nellore

The electromagnetic, axial and pseudoscalar nucleon to Delta form factors are calculated using dynamical domain wall fermions at a lattice spacing of a = 0.114 fm on a lattice of spatial size 2.74 fm and pion mass of 331 MeV. Pion pole…

High Energy Physics - Lattice · Physics 2010-11-05 C. Alexandrou , G. Koutsou , J. W. Negele , A. O'Cais , Y. Proestos , A. Tsapalis

The electromagnetic transition properties of the decuplet to octet baryon ($\Delta \rightarrow N\gamma$) is studied within the frame work of a hypercentral quark model. The confinement potential is assumed as hypercentral coloumb plus…

High Energy Physics - Phenomenology · Physics 2012-07-31 Kaushal Thakkar , Ajay Majethiya , P. C. Vinodkumar

In this article we address the physical basis of the deviation of hadron shapes from spherical symmetry (non-spherical amplitudes) with focus on the nucleon and $\Delta$. An overview of both the experimental methods and results and the…

High Energy Physics - Phenomenology · Physics 2009-01-06 A. M. Bernstein , C. N. Papanicolas

The three electromagnetic form factors of the $\Delta(1232)$ resonance, $G^*_M(q^2)$, $G^*_E(q^2)$, and $G^*_C(q^2)$ are obtained in the space-like region using a Dual Resonance Model realization of QCD in the large $N_c$ limit…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. A. Dominguez , R. Röntsch

The electromagnetic excitation of the $\Delta(1232)$-resonance plays an appreciable role in the Lamb shift and hyperfine structure of muonic and electronic hydrogen. Its effect appears at the subleading order $\mathcal{O}(\alpha^5)$,…

Nuclear Theory · Physics 2018-07-04 Franziska Hagelstein

An analysis of the baryon-baryon potential from the point of view of large-N(c) QCD is performed. A comparison is made between the N(c)-scaling behavior directly obtained from an analysis at the quark-gluon level to the N(c)-scaling of the…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. V. Belitsky , T. D. Cohen

The magnetic dipole G_M(Q^2), electric quadrupole G_E(Q^2), and Coulomb quadrupole G_C(Q^2) form factors, describing the spin-3/2 to spin-1/2 electromagnetic transitions, are investigated within the light cone QCD sum rules. The Q^2…

High Energy Physics - Phenomenology · Physics 2015-06-16 T. M. Aliev , Y. Oktem , M. Savci

We present a relativistic interpretation for why the proton's ratio of electric to magnetic form factor falls and for why the ratio of the Pauli to Dirac form factor varies as 1/Q. Reproducing the observed electric form factor of the…

Nuclear Theory · Physics 2017-08-23 Gerald A. Miller

In this paper, the implication of the extreme large $N_c$ limit for nucleon-nucleon cross section is examined. Starting from the $N_c$ scaling of the S-matrix elements, a relation between the total inelastic and total cross sections is…

Nuclear Theory · Physics 2014-02-26 Thomas D. Cohen , Vojtěch Krejčiřík

Predictions obtained with a confining, symmetry-preserving treatment of a vector-vector contact interaction at leading-order in a widely used truncation of QCD's Dyson-Schwinger equations are presented for \Delta and \Omega baryon elastic…

We present a calculation of the N to $\Delta$ electromagnetic transition amplitudes using the method of QCD sum rules. A complete set of QCD sum rules are derived for the entire family of transitions from the baryon octet to decuplet. They…

High Energy Physics - Phenomenology · Physics 2009-09-02 Lai Wang , Frank X. Lee

The details of the calculation of the two-boson exchange effects in the parity-violating elastic $ep$ scattering within a simple hadronic model, including both the nucleon and $\Delta(1232)$-resonance intermediate states, are presented. We…

Nuclear Theory · Physics 2010-04-14 Hai Qing Zhou , Chung Wen Kao , Shin Nan Yang , Keitaro Nagata

We use contracted spin-flavor symmetry which emerges in the large Nc limit of QCD to obtain relations between proton-proton and proton-neutron total cross sections for both polarized and unpolarized scattering. The formalism used is valid…

Nuclear Theory · Physics 2013-05-30 Thomas D. Cohen , Boris A. Gelman

We calculate the nucleons' electromagnetic polarizabilities in heavy baryon chiral perturbation theory including all terms to order ${\cal O} (q^4)$. The chiral prediction of the electric polarizabilities for the neutron and the proton are…

High Energy Physics - Phenomenology · Physics 2016-08-14 Véronique Bernard , Norbert Kaiser , Armin Schmidt , Ulf-G. Meißner

Transverse densities describe the spatial distribution of electromagnetic current in the nucleon at fixed light-front time. At peripheral distances b = O(M_pi^{-1}) the densities are governed by chiral dynamics and can be calculated…

High Energy Physics - Phenomenology · Physics 2016-06-29 C. Granados , C. Weiss

The resonant electric quadrupole amplitude in the transition $\gamma N\leftrightarrow\Delta(1232)$ is of great interest for the understanding of baryon structure. Various dynamical models have been developed to extract it from the…

Nuclear Theory · Physics 2008-11-26 P. Wilhelm , Th. Wilbois , H. Arenhoevel

Electromagnetic form factors of a massive neutrino are studied in a minimally extended standard model in an arbitrary $R_{\xi}$ gauge and taking into account the dependence on the masses of all interacting particles. The contribution from…

High Energy Physics - Phenomenology · Physics 2009-11-10 Maxim Dvornikov , Alexander Studenikin

We present recent lattice QCD results on nucleon form factors and N to Delta transition form factors. We predict the parity violating asymmetry in N to Delta and check the off-diagonal Goldberger-Treiman relation.

High Energy Physics - Lattice · Physics 2007-05-23 C. Alexandrou