Analysis of Φ Decay to 3γ Final States with the TELESIS

Abstract：

DAΦNE (Double Annular Φ factory for Nice Experiment) is the Frascati(Italy) electron positron collider operating at the energy of 510 MeV, a rather low energy with respect to the other existing factories. DAΦNE includes two collision points, and KLOE detector is located at one of these points. The KLOE detector is designed primarily for the goal of detecting direct CP violation in K⁰ decays with a sensitivity of ～10^－4 in R (ε′/ε), with a vast amount of other physics subjects. φ radiative dacays, especially its pure neutral final states are very important subjects to test the Chiral Perturbation Theory approach both in the anomalous and non-anomalous sectors. In this paper, a new kinematic fit method—TELESIS—is used for the data analysis of φ radiative decay φ→γη→3γ and φ→γπ⁰→3γ based on a part of 2000' data collected by KLOE detectors in DAΦNE, the φ produced cross section and the partial cross section of e⁺e^－→φ→γπ⁰→3γ have been obtained as follows:σe+e－→φ=(4.04±0.04±0.24)μb,σe+e－→φ→γπ0→3γ=(5.3±0.3±0.6)nb. These results are in good agreement with that of VEPP and theoretical predictions.