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Garcia-Recio, C

Publications and source records attributed to Garcia-Recio, C.

SU(6) superset of SU(3) x SU(2) and SU(8) superset of SU(4) x SU(2) Clebsch-Gordan coefficients

Tables of scalar factors are presented for 63 x 63 and 120 x 63 in SU(8) superset of SU(4) x SU(2), and for 35 x 35 and 56 x 35 in SU(6) superset of SU(3) x SU(2). Related tables for SU(4) superset of SU(3) x U(1) and SU(3) superset of SU(2) x U(1) are also provided so that the Clebsch-Gordan coefficients can be completely reconstructed. These are suitable to study meson-meson and baryon-meson interactions within a spin-flavor symmetric scheme.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Low-lying even-parity meson resonances and spin-flavor symmetry

Based on a spin-flavor extension of chiral symmetry, a novel s-wave meson-meson interaction involving members of the {rho} nonet and of the {pi} octet is introduced, and its predictions are analyzed. The starting point is the SU(6) version of the SU(3)-flavor Weinberg-Tomozawa Lagrangian. SU(6) symmetry-breaking terms are then included to account for the physical meson masses and decay constants in a way that preserves (broken) chiral symmetry. Next, the T-matrix amplitudes are obtained by solving the Bethe-Salpeter equation in a coupled-channel scheme, and the poles are identified with their possible Particle Data Group counterparts. It is shown that most of the low-lying even-parity Particle Data Group meson resonances, especially in the J{sup P}=0{sup +} and 1{sup +} sectors, can be classified according to multiplets of SU(6). The f{sub 0}(1500), f{sub 1}(1420), and some 0{sup +}(2{sup ++}) resonances cannot be accommodated within this scheme, and thus they would be clear candidates to be glueballs or hybrids. Finally, we predict the existence of five exotic resonances (I{>=}3/2 and/or |Y|=2) with masses in the range of 1.4-1.6 GeV, which would complete the 27{sub 1}, 10{sub 3}, and 10{sub 3}* multiplets of SU(3) x SU(2).

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Exotic dynamically generated baryons with C = -1

We follow a model based on the SU(8) symmetry for the interaction of mesons with baryons. The model treats on an equal footing the pseudo-scalars and the vector mesons, as required by heavy quark symmetry. The T-matrix calculated within an unitary scheme in coupled channels has poles which are interpreted as baryonic resonances.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗