Observation of Observation of tensor glueball in the reactions p anti-p -> pi-pi, eta-eta, eta-eta'

Abstract

Partial wave analysis of the reactions p anti-p -> pi-pi, eta-eta, eta-eta' in the region of invariant masses 1900-2400 MeV indicates to the existence of four relatively narrow tensor-isoscalar resonances f_2(1920), f_2(2020), f_2(2240), f_2(2300) and the broad state f_2(2000). The determined decay couplings of the broad resonance f_2(2000)-> pi0-pi0, eta-eta, eta-eta' satisfy the relations appropriate to those of tensor glueball, while the couplings of other tensor states do not, thus verifying the glueball nature of f_2(2000).