Orbitally Excited Baryon Spectroscopy in the 1/Nc Expansion

The discussion of the 70-plet of negative parity baryons illustrates the large Nc QCD approach to orbitally excited baryons. In the case of the l=1 baryons the existing data allows to make numerous predictions to first order in the SU(3) symmetry breaking. New relations between splittings are found that follow from the spin-flavor symmetry breaking. The Lambda(1405) is well described as a three-quark state and a spin-orbit partner of the Lambda(1520). Singlet states with higher orbital angular momentum are briefly discussed.Comment: 10 pages. Invited talk at The Phenomenology of Large Nc QCD, Tempe, Arizona, 9-11 Jan 200

Hyperon Polarizabilities in the Bound State Soliton Model

A detailed calculation of electric and magnetic static polarizabilities of octet hyperons is presented in the framework of the bound state soliton model. Both seagull and dispersive contributions are considered, and the results are compared with different model predictions.Comment: 19 pages, plain Latex, no figure

Multibaryons with heavy flavors in the Skyrme model

We investigate the possible existence of multibaryons with heavy flavor quantum numbers using the bound state approach to the topological soliton model and the recently proposed approximation for multiskyrmion fields based on rational maps. We use an effective interaction lagrangian which consistently incorporates both chiral symmetry and the heavy quark symmetry including the corrections up to order 1/m_Q. The model predicts some narrow heavy flavored multibaryon states with baryon number four and seven.Comment: 8 pages, no figures, RevTe

Negative Parity 70-plet Baryon Masses in the 1/N{sub c} Expansion

The masses of the negative parity SU(6) 70-plet baryons are analyzed in the 1/N{sub c} expansion to order 1/N{sub c} and to first order in SU(3) breaking. At this level of precision there are twenty predictions. Among them there are the well known Gell-Mann Okubo and equal spacing relations, and four new relations involving SU(3) breaking splittings in different SU(3) multiplets. Although the breaking of SU(6) symmetry occurs at zeroth order in 1/N{sub c}, it turns out to be small. The dominant source of the breaking is the hyperfine interaction which is of order 1/N{sub c}. The spin-orbit interaction, of zeroth order in 1/N{sub c}, is entirely fixed by the splitting between the singlet states A(1405) and A(1520), and the spin-orbit puzzle is resolved by the presence of other zeroth order operators involving flavor exchange