TTP00-30 Search for the CP Forbidden Decay eta to 4 pi0

We report the first determination of the upper limit for the branching ratio of the CP forbidden decay eta to 4 pi0. No events were observed in a sample of 3.0×10^7 eta decays. The experiment was performed with the Crystal Ball multiphoton spectrometer installed in a separated pi- beam at the AGS (Alternating Gradient Synchrotron). At the 90% confidence limit, B(eta to 4 pi0) ⇐ 6.9×10^-7.