Pseudoscalar states in J/ψ → γVV decays. Results from DM2

We present new results from the DM2 experiment on the ηc-state and the pseudoscalar production seen at the threshold of the vector-vector radiative decays at J/ψ. The ηc shows a vector-vector dominance in its decays and has a decay pattern which follows the SU(3)F symmetry prediction, this being in contradiction with previous measurements. New pseudoscalar states are clearly present in the invariant mass spectrum of ϱ0ϱ0. There are at least three different resonances, here named L1, L2, L3 to underline a supposed common origin. These states have no direct interpretation in the usual qq model and they are believed to have an isoscalar nature. An interesting new upper limit on the gT's(2000 ÷ 2500 MeV/c2) production at J/ψ is given as a by-product of the ϱ0ϱ0 analysis.