Chiral Symmetry and Hyperfine Quark-Antiquark Splittings

Abstract

We briefly review theoretical calculations for the pseudoscalar-vector meson hyperfine splitting with no open flavor and also report a many body field theoretical effort to assess the impact of chiral symmetry in the choice of effective potentials for relativistic quark models. Our calculations predict the missing eta_b meson to have mass near 9400 $MeV$. The radial excitation ${\eta }_c(2S)$ is in agreement with the measurements of the BELLE and most recently BABAR collaborations.

Comments: European HEP conference proceedings (Aachen, July 2003). A few typographical errors corrected