Revisiting Scalar Glueballs

Abstract

It is commonly believed that the lowest-lying scalar glueball lies somewhere in the isosinglet scalar mesons $f_0(1370),f_0(1500)$ and $f_0(1710)$ denoted generically by $f_0$. In this work we consider lattice calculations and experimental data to infer the glue and $q\bar{q}$ components of $f_0$. These include the calculations of the scalar glueball masses in quenched and unquenched lattice QCD, measurements of the radiative decays $J/\psi \to \gamma f_0$, the ratio of $f_0$ decays to $\pi \pi$ and $K\bar{K}$, the ratio of $J/\psi$ decays to $f_0(1710)\omega$ and $f_0(1710)\varphi$, the $f_0$ contributions to $B_s\to J/\psi {\pi }^{+}{\pi }^{-}$, and the near mass degeneracy of $a_0(1450)$ and $K_0^{\ast }(1430)$. All analyses suggest the prominent glueball nature of $f_0(1710)$ and the flavor octet structure of $f_0(1500)$.

Comments: 21 pages, comments on the f0(1370) meson were made, uncertainties in the glueball-quarkonium mixing matrix elements included, discussions on the \eta\eta modes and many new references added. Version to appear in PRD