Measurement of the $\hat{I}\cdot \to 3\ddot{I}{€}^0$ slope parameter $\hat{I}\pm$ with the KLOE detector

Abstract

We present a measurement of the slope parameter $\hat{I}\pm$ for the $\hat{I}\cdot \to 3\ddot{I}{€}^0$ decay, with the KLOE experiment at the DA$\hat{I}¦$NE $\ddot{I}•$-factory, based on a background free sample of $\sim$ 17 millions $\hat{I}\cdot$ mesons produced in $\ddot{I}•$ radiative decays. By fitting the event density in the Dalitz plot we determine $\hat{I}\pm =-0.0301\pm 0.0035stat{}_{-0.0035}^{+0.0022}syst$. The result is in agreement with recent measurements from hadro- and photo-production experiments.

14 pages, 11 figures