2008/01/31 by Amir H. Fariborz, Renata Jora, Joseph Schechter +1 · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.77.094004
published as Phys.Rev.D77:094004,2008 · reference added, minor typos corrected
arxiv created 2008/02/01 · openalex publication_date 2008/05/06 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
It is well known that the instanton approach to QCD generates an effective term which looks like a three-flavor determinant of quark bilinears. This has the right behavior to explain the unusual mass and mixing of the \ensuremathη(958) meson, as is often simply illustrated with the aid of a linear SU(3) sigma model. It is less well known that the instanton analysis generates another term which has the same transformation property but does not have a simple interpretation in terms of this usual linear sigma model. Here we point out that this term has an interpretation in a generalized linear sigma model containing two chiral nonets. The second chiral nonet is taken to correspond to mesons having two quarks and two antiquarks in their makeup. The generalized model seems to be useful for learning about the spectrum of low-lying scalar mesons which have been emerging in the last few years. The physics of the new term is shown to be related to the properties of an excited \ensuremathη^\ensuremath' state present in the generalized model and for which there are some experimental candidates.