Measurement of the η→3π0 slope parameter α with the KLOE detector

We present a measurement of the slope parameter α for the η→3π0 decay, with the KLOE experiment at the DAΦNE ϕ-factory, based on a background free sample of ∼17 million η mesons produced in ϕ radiative decays. By fitting the event density in the Dalitz plot we determine α=−0.0301±0.0035stat−0.0035+0.0022syst. The result is in agreement with recent measurements from hadro- and photo-production experiments.