Hunting the Scalar Glueball: Prospects for BES III

Abstract

The search for the ground state scalar glueball G_0 is reviewed. Spin zero glueballs will have unique dynamical properties if the <G_0|\bar qq> amplitude is suppressed by chiral symmetry, as it is to all orders in perturbation theory: for instance, mixing of G_0 with \bar qq mesons would be suppressed, radiative J/psi decay would be a filter for new physics in the spin zero channel, and the decay G_0 \to \bar KK could be enhanced relative to G_0 \to ππ. These properties are consistent with the identification of f_0(1710) as the largely unmixed ground state scalar glueball, while recent BES data implies that f_0(1500) does not contain the dominant glueball admixture. Three hypotheses are discussed: that G_0 is 1) predominantly f_0(1500) or 2) predominantly f_0(1710) or 3) is strongly mixed between f_0(1500) and f_0(1710).