Related papers: Baryons from Quarks in the $1/N$ Expansion
A systematic expansion in 1/N is constructed for baryons in QCD. Predictions of the 1/N expansion at leading and subleading order for baryon axial current coupling constant ratios such as F/D, baryon masses and magnetic moments are derived.…
Using recently-developed diagrammatic techniques, I derive some general results concerning baryons in the $1/N$ expansion, where $N$ is the number of QCD colors. I show that the spin-flavor relations which hold for baryons in the large-$N$…
We consider the baryon octet and decuplet magnetic moments in a simultaneous expansion in $m_s$ and $1/N$ taking $N_F / N \sim 1$, where $N$ is the number of QCD colors and $N_F$ is the number of light quark flavors. At leading order in…
The chiral Lagrangian for baryons is formulated in an expansion in 1/N_c. The chiral Lagrangian implements the contracted spin-flavor symmetry of large-N_c baryons as well as nonet symmetry of the leading planar diagrams. Large-N_c…
We consider flavor breaking in the the octet and decuplet baryon masses at second order in large-$N$ chiral perturbation theory, where $N$ is the number of QCD colors. We assume that $1/N \sim 1/N_F \sim m_s / \Lambda \gg m_{u,d}/\Lambda,…
The spin-flavor structure of large N baryons is described in the 1/N expansion of QCD using quark operators. The complete set of quark operator identities is obtained, and used to derive an operator reduction rule which simplifies the 1/N…
Meson loop corrections to baryon axial currents are computed in the 1/N expansion. It is already known that the one-loop corrections are suppressed by a factor 1/N; here it is shown that the two-loop corrections are suppressed by (1/N)^2.…
A spin-flavor symmetry emerges for baryons in the large-N_c limit. Large-N_c baryons form irreducible representations of the spin-flavor algebra, and their static properties can be computed in a systematic expansion in 1/N_c. Symmetry…
The quadrupole moments of ground state baryons are discussed in the framework of the 1/N(c) expansion of QCD, where N(c) is the number of color charges. Theoretical expressions are first provided assuming an exact SU(3) flavor symmetry, and…
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…
This thesis deals with the study of baryon spectra in the context of the $1/N_c$ expansion. The standard tool to study baryon properties is the constituent quark model. The results are naturally model dependent. The $1/N_c$ expansion…
The baryon vector current is computed at one-loop order in large-Nc baryon chiral perturbation theory, where Nc is the number of colors. Loop graphs with octet and decuplet intermediate states are systematically incorporated into 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…
A $1/\N$ expansion of the chiral Lagrangian for baryons is formulated and used to study the low-energy dynamics of baryons interacting with the pion nonet $\pi$, $K$, $\eta$ and $\eta^\prime$ in a combined expansion in chiral symmetry…
We show how to match quark models to the 1/Nc expansion of QCD. As an example we discuss in detail the mass operator of orbitally excited baryons and match it to the one-gluon exchange and the one-boson exchange variants of the quark model.…
A family of simply solvable covariant quark models for the baryons is presented. With optimal parameter choices the models reproduce the empirical spectra of the baryons in all flavor sectors to an accuracy of a few percent. Complete…
We study the two-color QCD matter within two fundamental quark flavors via both chiral perturbation theory and Nambu--Jona-Lasinio model methods. The effective Lagrangian described by low lying meson and baryon, i.e., diquark, is derived,…
The generalization of QCD to many colors is not unique; each distinct choice corresponds to a distinct 1/N_c expansion. The familiar 't Hooft N_c -> \infty limit places quarks in the fundamental representation of SU(N_c), while an…
In this thesis we calculate the baryon axial current within the combined framework of the $1/N_c$ expansion and chiral perturbation theory, where $N_c$ is the number of colors. This calculation shall consider Feynman diagrams to order of…
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…