Scalar isoscalar mesons and the scalar glueball from radiative $J/ψ$ decays

Abstract

A coupled-channel analysis of BESIII data on radiative J/ψ decays into ππ, K K, ηη and ωφ has been performed. The partial-wave amplitude is constrained by a large number of further data. The analysis finds ten isoscalar scalar mesons. Their masses, widths and decay modes are determined. The scalar mesons are interpreted as mainly SU(3)-singlet and mainly octet states. Octet isoscalar scalar states are observed with significant yields only in the 1500-2100 MeV mass region. Singlet scalar mesons are produced over a wide mass range but their yield peaks in the same mass region. The peak is interpreted as scalar glueball. Its mass and width are determined to M = 1865±25 +10 −30 MeV and Γ = 370±50 +30 −20 MeV, its yield in radiative J/ψ decays to (5.8 ± 1.0) 10 −3 .

Quenched glueballs in the DSE/BSE framework

“…Their gluonic content as determined from radiative J/ψ decays was discussed recently in Refs. [6][7][8]. On the theory side, the benchmark has been lattice simulations of the glueball spectrum [9][10][11][12].…”