Evidence for f 2 (1720) production in the reaction pomeron-pomeron→π + π - π + π -

Data are presented on pomeron-pomeron interactions which produce a central π+π−π+π− system in proton-proton collisions at √s=62 GeV at the CERN Intersecting Storage Rings. A spin-parity analysis of the π+π−π+π− system shows evidence for the production of the statef2 (1720) with decay to ρ0π+π−. Since pomeron-pomeron interactions are expected to favor the production of gluonic bound states, observation of thef2 (1720) supports earlier interpretations of it as a glueball. In addition, enhancements near threshold give indication of the statef2 (1270) decaying to ρ0ρ0 and the statef0 (1400) decaying to ρ0π+π−.