Determination of $\hat{I}\cdot \to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0$ Dalitz plot slopes and asymmetries with the KLOE detector

Abstract

We have studied, with the KLOE detector at the DA$\hat{I}¦$NE $\hat{I}¦$-Factory, the dynamics of the decay $\hat{I}\cdot \to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0$ using $\hat{I}\cdot$ mesons from the decay $\ddot{I}•\to \hat{I}\cdot {\hat{I}}^3$ for an integrated luminosity $\mathcal{L}$ = 450 pb${}^{-1}$. From a fit to the Dalitz plot density distribution we obtain a precise measurement of the slope parameters. An alternative parametrization relates the $\ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0$ slopes to that for $\hat{I}\cdot \to 3\ddot{I}{€}^0$ showing the consistency of KLOE results for both channels. We also obtain the best confirmation of the $C$-invariance in the $\hat{I}\cdot \to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0$ decay.

15 pages, 7 figures