Related papers: N* Properties from the 1/N_c Expansion
The spectrum of excited baryons in the $N$ = 2 band is reanalys9 pagesed in the $1/N_c$ expansion method, with emphasis on hyperons. Predictions are made for the classification of these excited baryons into SU(3) singlets, octets and…
We establish a connection between the quark model and the 1/N_c expansion mass formulas used in the description of baryon resonances. We show that a remarkable compatibility exists between the two methods in the light and heavy baryon…
The nucleon-nucleon potential is analysed using the 1/N_c expansion of QCD. The NN potential is shown to have an expansion in 1/N_c^2, and the strengths of the leading order central, spin-orbit, tensor, and quadratic spin-orbit forces…
We present a model-independent analysis of the mass spectrum of nonstrange l=1 baryons in large N_c QCD. The 1/N_c expansion is used to select and order a basis of effective operators that spans the nine observables (seven masses and two…
The mass spectrum of the L=1 orbitally excited heavy baryons with light quarks in the spin-flavor symmetric representation is studied by the $1/N_c$ expansion method in the framework of the heavy quark effective theory. The mixing effect…
L=1 excited heavy baryon masses are analyzed by heavy quark and large N_c expansions. In heavy quark limit, mass is parameterized by \Lambda-bar and it is expanded further by spin-flavor breaking operators to the zeroth order of 1/N_c.…
The baryon mass operator is studied within a combined expansion in $1/N_c$ and perturbative $SU(3)$ flavor symmetry breaking, where $N_c$ denotes the number of quark charges. Flavor projection operators are used to classify the baryon…
We derive consistency conditions which constrain the possible form of the strong couplings of the excited baryons to the pions. The consistency conditions follow from requiring the pion-excited baryon scattering amplitudes to satisfy the…
This talk comments the main features of a hadronic description of QCD in the limit of large number of colours. We derive a quantum field theory for mesons based on chiral symmetry and a perturbative expansion in 1/NC. Some large-NC and…
This talk reviews recent developments in the use of large $N_c$ QCD in the description of baryonic resonances. The emphasis is on the model-independent nature of the approach. Key issues discussed include the spin-flavor symmetry which…
We analyze the photo-production helicity amplitudes for the positive parity excited baryons in the context of the $1/N_c$ expansion of QCD. The results show that sub-leading corrections in $1/N_c$ are important and that, while 1-body…
The mass spectra of the L=1 orbitally excited heavy baryons with light quarks in both the spin-flavor symmetric and the mixed representations are studied by the $1/N_c$ expansion method in the framework of the heavy quark effective theory.…
The 1/N_c expansion provides a theoretical method for analyzing the spin-flavor symmetry properties of baryons in QCD that is quantitative, systematic and predictive. An exact spin-flavor symmetry exists for large-N_c baryons, whereas for…
The $1/N_c$ power countings for baryon decays and configuration mixings are determined by means of a non-relativistic quark picture. Such countings are expected to be robust under changes in the quark masses, and therefore valid as these…
The physics of the orbitally excited baryons simplifies drastically in the large Nc limit. The states are arranged into irreducible representations of the contracted SU(4)_c symmetry, with mixing angles determined exactly. The ratios of the…
We show that a remarkable compatibility exists between the results of a potential model with constituent quarks and the 1/Nc expansion mass formula for strange and nonstrange baryon resonances. Such compatibility brings support to the basic…
We establish a connection between the quark model results and the $1/N_c$ expansion mass formula used in the description of baryon resonances. We show that a remarkable compatibility exists between the two methods.
We analyze excited baryon properties via a 1/N_c expansion from two perspectives: as resonances in meson-nucleon scattering, and as single-quark excitations in the context of a simple quark model. For both types of analysis one can derive…
We study excited baryon decay widths in large N_c QCD. It was suggested previously that some spin-flavor mixed-symmetric baryon states have strong couplings of O(N_c^{-1/2}) to nucleons [implying narrow widths of O(1/N_c)], as opposed to…
A good agreement between a flux tube-based quark model of light baryons (strange and nonstrange) and the $1/N_c$ expansion mass formula has been found in previous studies. In the present work a larger connection is established between the…