Toy model for two chiral nonets

Journal Article · Mon Aug 01 04:00:00 EDT 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.72.034001· OSTI ID:20711209

Fariborz, Amir H ^[1]; Jora, Renata; Schechter, Joseph ^[2]

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1. Department of Mathematics/Science, State University of New York Institute of Technology, Utica, New York 13504-3050 (United States)
2. Department of Physics, Syracuse University, Syracuse, New York 13244-1130 (United States)

Motivated by the possibility that nonets of scalar mesons might be described as mixtures of 'two quark' and 'four quark' components, we further study a toy model in which corresponding chiral nonets (containing also the pseudoscalar partners) interact with each other. Although the 'two quark' and 'four quark' chiral fields transform identically under SU(3){sub L}xSU(3){sub R} transformations, they transform differently under the U(1){sub A} transformation which essentially counts total (quark+antiquark) content of the mesons. To implement this, we formulate an effective Lagrangian which mocks up the U(1){sub A} behavior of the underlying QCD. We derive generating equations which yield Ward identity type relations based only on the assumed symmetry structure. This is applied to the mass spectrum of the low lying pseudoscalars and scalars, as well as their 'excitations'. Assuming isotopic spin invariance, it is possible to disentangle the amount of 'two quark' vs 'four quark' content in the pseudoscalar {pi},K,{eta}-type states and in the scalar {kappa}-type states. It is found that a small 'four quark' content in the lightest pseudoscalars is consistent with a large 'four quark' content in the lightest of the scalar {kappa} mesons. The present toy model also allows one to easily estimate the strength of a 'four quark' vacuum condensate. There seems to be a rich and interesting structure.

• OSTI ID: 20711209
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 3 Vol. 72; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CHIRAL SYMMETRY
CHIRALITY
EXCITATION
ISOSPIN
KAONS
LAGRANGIAN FIELD THEORY
LAGRANGIAN FUNCTION
MASS SPECTRA
MESON NONETS
PIONS
QUANTUM CHROMODYNAMICS
QUARK MODEL
QUARKS
SCALAR MESONS
SPARTICLES
SU-3 GROUPS
UNITARY SYMMETRY
WARD IDENTITY