Baryon masses in the 1/Nc expansion

Baryon Masses in the 1/n C Expansion

The masses of baryons and heavy quark baryons are studied analytically in an expansion in 1/Nc, SU (3) flavor symmetry breaking, and heavy-quark symmetry breaking. The measured baryon masses are in striking agreement with the 1/Nc hierarchy.

Charm and bottom baryon masses in the 1/N expansion

The 1/Nc expansion has proven useful for studying the spin-flavor properties of baryons containing light quarks. A spin-flavor symmetry for baryons is defined in large-Nc QCD. Away from the Nc → ∞ limit, 1/Nc corrections which break large-Nc baryon spin-flavor symmetry can be classified in terms of the spin and flavor symmetries which remain for finite Nc. Since explicit SU(3) flavor symmetry b...

Baryon masses in a chiral expansion with meson-baryon form factors

The chiral expansion of the one-loop corrections to baryon masses is examined in a generic meson-cloud model with meson-baryon form factors. For pion loops, the expansion is rapidly convergent and at fourth order inmπ accurately reproduces the full integral. In contrast, the expansion is found to converge very slowly for kaon loops, raising questions about the usefulness of chiral expansions fo...

Chiral expansion of baryon masses and σ–terms

We analyze the octet baryon masses and the pion/kaon–nucleon σ–terms in the framework of heavy baryon chiral perturbation theory. We include all terms up-to-and-including quadratic order in the light quark masses, mq. We develop a consistent scheme to estimate low–energy constants related to scalar–isoscalar operators in the framework of resonance exchange involving one–loop graphs. The pertine...

Analysis of the [56, 4 +] Baryon Masses in the 1/Nc Expansion ∗