English
Related papers

Related papers: Nucleon Excitations

200 papers

We derive the equation of state of symmetric nuclear matter in a relativistic theory with $\sigma$ and $\omega$ exchange. We take a chiral version of this model which insures all the chiral constraints. Going beyond the mean field approach…

Nuclear Theory · Physics 2008-11-26 G. Chanfray , M. Ericson

The electromagnetic form factors of the nucleon have been calculated in a chiral constituent-quark model. The nucleon wave functions are obtained by solving a Schr\"odinger-type equation for a semi-relativistic Hamiltonian with an effective…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Boffi , P. Demetriou , M. Radici , R. F. Wagenbrunn

Nuclear saturation and the symmetry energy are key properties of low-energy nuclear physics that depend on fine details of the nuclear interaction. The equation-of-state around saturation is also an important anchor for extrapolations to…

Nuclear Theory · Physics 2024-06-18 W. G. Jiang , C. Forssén , T. Djärv , G. Hagen

We introduce an improved mass formula for the nucleon and delta resonances and show how it emerges from AdS/QCD in a straightforward extension of the 'metric soft wall' gravity dual. The resulting spectrum depends on just one adjustable…

High Energy Physics - Phenomenology · Physics 2014-11-18 Hilmar Forkel , Eberhard Klempt

We present a lattice calculation of the leading corrections to the masses of nucleons and $\Delta$ resonances. These are obtained in QCD+QED at $1$st order in the Isospin Breaking parameters $\alpha_{EM}$, the electromagnetic coupling, and…

High Energy Physics - Lattice · Physics 2022-07-12 Simone Romiti

We study the static scalar susceptibility of the nuclear medium, i.e., the change of the quark condensate for a small modification of the quark mass. In the linear sigma model it is linked to the in-medium sigma propagator. At ordinary…

Nuclear Theory · Physics 2007-05-23 G. Chanfray , M. Ericson

Various aspects of the Generalised Nambu-Jona-Lasinio model for QCD in four dimensions are reviewed. The properties of mesonic excitations are discussed in detail, with special attention paid to the chiral pion. The spontaneous chiral…

High Energy Physics - Phenomenology · Physics 2017-09-05 Yu. S. Kalashnikova , A. V. Nefediev , J. E. F. T. Ribeiro

Recent developments in calculations of low energy nucleon properties utilizing effective chiral field theories with explicit spin 3/2 matter fields are presented. In particular, the role of Delta resonances in microscopic calculations of…

Nuclear Theory · Physics 2017-08-23 Thomas R. Hemmert

We study the momentum and the quark mass dependence of the axial nucleon to Delta(1232) transition form factors in the framework of non-relativistic chiral effective field theory to leading-one-loop order. The outcome of our analysis…

High Energy Physics - Phenomenology · Physics 2009-02-23 Massimiliano Procura

In the article "On chiral symmetry restoration at finite density in large-$N_c$ QCD" by Adhikari, Cohen, Ayyagari and Strother [Phys. Rev. C 83, 065201 (2011)] the description of dense nuclear matter by means of Skyrmions in hyperspherical…

Nuclear Theory · Physics 2015-06-22 Hilmar Forkel

We consider chiral perturbation theory with an explicit broad $\sigma$-meson and study its contribution to the scalar form factors of the pion and the nucleon. Our goal is to learn more about resonance saturation in the scalar sector.

High Energy Physics - Phenomenology · Physics 2019-10-30 Y. Ünal , Ulf-G. Meißner

The relevance of the pion mass, provenient from a term which explicitely breaks chiral symmetry in the Lagrangian, for nucleon magnetic moment in the frame of the Skyrmion model in two different versions: the usual Skyrme model and a…

High Energy Physics - Lattice · Physics 2007-05-23 Fabio L. Braghin

The nucleon resonances near 2 GeV are investigated through the $\Sigma$(1385) and $\Lambda(1520)$ photoproductions within a Regge-plus-resonance approach based on the new experimental data released by the CLAS Collaboration. The…

Nuclear Theory · Physics 2016-06-22 Jun He

Heavy baryon chiral perturbation theory ($\chi$PT), where the $\Delta$ resonance is included, is used in order to examine the axial charged-current component of the weak interaction process at low neutrino energies. At leading chiral order…

Nuclear Theory · Physics 2019-03-13 Fred Myhrer

Quenched lattice QCD simulations and quenched chiral perturbation theory are used together for this study of strangeness in the nucleon. Dependences of the matrix elements on strange quark mass, valence quark mass and momentum transfer are…

High Energy Physics - Phenomenology · Physics 2009-11-07 Randy Lewis , W. Wilcox , R. M. Woloshyn

Nucleon electromagnetic form factors are considered in the framework of the generalized Skyrme model with dilaton-quarkonium field. In our recent publication we have got big discrepancies between calculated form factors and dipole…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. E. Lassila , E. N. Magar , V. A. Nikolaev , V. Yu. Novozhilov , O. G. Tkachev

We present a relativistic chiral theory of nuclear matter which includes the effect of confinement. Nuclear binding is obtained with a chiral invariant scalar background field associated with the radial fluctuations of the chiral condensate…

Nuclear Theory · Physics 2009-01-19 G. Chanfray , M. Ericson

We discuss the properties of the nucleon (N) and its excited state with odd parity (N*) under the aspect of chiral symmetry, identifying them with suitable representations of the chiral group. It is shown that there are two distinctive…

Nuclear Theory · Physics 2007-05-23 D. Jido

While bulk properties of stable nuclei are successfully reproduced by mean-field theories employing effective interactions, the dependence of the centroid energy of the electric giant dipole resonance on the nucleon number A is not. This…

Nuclear Theory · Physics 2015-06-05 N. Lyutorovich , V. Tselyaev , J. Speth , S. Krewald , F. Gruemmer , P. -G. Reinhard

The scalar isoscalar form factor of the nucleon is calculated in the limit of a large number of colours in the framework of the chiral quark-soliton model. The calculation is based on an approximation justified by arguments from the…

High Energy Physics - Phenomenology · Physics 2009-11-10 P. Schweitzer