Radiative decays of the psi(3097) to two meson final states

The MARK III detector operating at the SPEAR storage ring has acquired a sample of 2.7 x 106 produced psi(3097)'s. These events are used to investigate the radiative decays of the psi to two meson final states. Such decays are of topical interest because of the unusual QCD laboratory they provide - of particular interest is the possibility of observing glueball states. The process psi → γπ+π- is studied. The f(1270) tensor meson is observed and the helicity structure of its production is measured. The data indicate that helicity 2 is suppressed, in disagreement with lowest order QCD calculations. Evidence is presented for the first observation of the theta(1700) in the π+π- final state. The strong, but not complete, suppression of this state in the ππ channel, combined with the absence of a J/sup P/ = 2+ signal in a recent MARK III analysis of psi → γ rho rho, suggest a very mysterious nature for the theta(1700). The process psi → γK+K- is also studied. The f'(1515) tensor meson is observed with a branching ratio in agreement with the SU(3) symmetry prediction for the standard two gluon radiative decay diagram with no mixing corrections. The helicity structure of the f'(1515) is measured for the first time, and is found to be similar to that of the f(1270). The theta(1700) is observed with high statistics. Its spin and parity are measured, with the result that J/sup P/ = 2+ is preferred over J/sup P/ = 0+ at the 99.9% C.L. In addition, evidence is presented for a remarkable narrow state, designated the xi(2220). Its parameters are measured to be: m = 2.218 +- 0.003 +- 0.010 GeV, GAMMA less than or equal to 0.040 GeV at 95% C.L., and BR(psi → γxi(2220))BR(xi(2220) → K+K-) = (5.7 +- 1.9 +- 1.4) x 10-5