SU(6) extension of the Weinberg-Tomozawa meson-baryon Lagrangian

Abstract

A consistent SU(6) extension of the Weinberg-Tomozawa meson-baryon chiral Lagrangian is constructed which incorporates vector meson and baryon decuplet degrees of freedom. The corresponding Bethe-Salpeter approximation predicts the existence of an isoscalar spin-parity 3 2 − K * N bound state (strangeness +1) with a mass around 1.7-1.8 GeV. It is the highest hypercharge state of an antidecuplet SU(3) representation and it is unstable through K * decay. The estimated width of this state (neglecting d-wave KN decay) turns out to be small (Γ ≤ 15 MeV). Clear signals of this resonance would be found in reactions like γp →K 0 pK + π − by looking at the three body pK + π − invariant mass.

Strategy to find the twoΛ(1405)states from lattice QCD simulations

“…After the work of Ref. [11], all further works on the chiral unitary approach have corroborated the two poles, with remarkable agreement for the pole at higher energy and larger variations for the pole at lower energies [12][13][14][15][16][17][18][19].…”

Photon inducedΛ(1520)production and the role of theK*exchange

“…On the other hand, recently, a consistent SU(6) extension of the Weinberg-Tomozawa (WT) SU(3) chiral Lagrangian has been derived by García-Recio et al [18]. In this manner, the lowest-lying meson vector nonet and baryon 3=2 decuplet hadrons are considered in addition to the members of the pion and nucleon octets originally included in the WT SU(3) interaction term.…”

Open-charm mesons in nuclear matter at finite temperature beyond the zero-range approximation

“…In the modern language of chiral Lagrangians those states emerge from the scattering of the 0 − octet Goldstone bosons off baryons of the 1/2 + octet. Moreover, Pand D-wave baryonic resonances have been generated based on the SU(3) leading-order chiral Lagrangian by means of meson scattering off baryons of the 3/2 + decuplet [50][51][52][53] and incorporating vector-meson degrees of freedom [54][55][56][57][58][59]. Molecular states of two pseudoscalar mesons and one baryon [60][61][62][63][64] have also been studied to interpret low-lying 1/2 + states.…”

“…The extension to Dwave J = 3/2 − resonances was first attempted by extending the basis to include the J = 3/2 + baryons [76]. In order to be consistent with the spin-flavor heavy-quark symmetry (HQS) [77][78][79], the vector mesons were incorporated later within a SU(8)-inspired model [80,81], similar to the SU (6) one developed in the light sector [55,56]. An alternative approach based on the local hidden gauge formalism has recently become available [82].…”