Meson U(3)L⊗U(3)R chiral theory with flavor and nonet symmetry breaking Original Research Article

An extended U(3)L⊗U(3)R chiral effective field theory which includes pseudoscalar and vector meson nonets as dynamic variables is presented. The theory combines a hidden local symmetry approach with a general procedure of including the η′ meson into chiral theory, and accounts for direct and indirect flavor and nonet symmetry breaking effects via a mechanism based on the quark mass matrix. The theory is applied to anomalous radiative decays of pseudoscalar and vector mesons, using particle mixing schemes that correspond to different symmetry breaking assumptions and are uniquely determined by the Lagrangian presumed. Radiative decays of light flavor mesons are best explained within the framework of a single mixing angle scheme, providing evidence for SU(3)F and nonet symmetry breaking. Based on our general treatment of symmetry breaking and the analysis of radiative decays we propose the value θP=−14.3±2.2.