Further Search for the Two-Photon Production of the Glueball Candidate $f_{J}(2220)$

TL;DR

This study searches for the two-photon production of the $f_J(2220)$ glueball candidate and finds no evidence, setting upper limits that support its substantial gluonic content.

Contribution

The paper provides new upper limits on the two-photon production of $f_J(2220)$ and evaluates its stickiness, reinforcing its potential gluonic nature.

Findings

No evidence for two-photon production of $f_J(2220)$

Upper limit on $ ext{Gamma}_{two-photon} imes BR( ext{pi+ pi-})$ is 2.5 eV

Stickiness of $f_J(2220)$ exceeds 102 at 95% CL

Abstract

The CLEOII detector at the Cornell e+ e- storage ring CESR has been used to search for the two-photon production of the $f_J(2220)$ decaying into pi+ pi-. No evidence for a signal is found in data corresponding to an integrated luminosity of 4.77/fb and a 95% CL upper limit on $\Gamma_{two-photon} * BR{pi+ pi-}$ of 2.5 eV is set. If this result is combined with the BES Collaboration's measurement of $f_J(2220) -> pi+ pi-$ in radiative $J/\psi$ decay, a 95% CL lower limit on the stickiness of the $f_J(2220)$ of 73 is obtained. If the recent CLEO result for $\Gamma_{two-photon} * BR{\K_S K_S}$ is combined with the present result, the stickiness of the $f_J(2220)$ is found to be larger than 102 at the 95% CL. These results for the stickiness (the ratio of the probabilities for two-gluon coupling and two-photon coupling) provide further support for a substantial neutral parton content in the $f_J(2220)$.