Search for the KS → 3π0 decay with the KLOE detector
Institute of Physics, Jagiellonian University, PL-30-059 Cracow, Poland
a e-mail: Michal.Silarski@lnf.infn.it
The KS → 3π0 decay is a pure CP violating process which, assuming CPT invariance, gives access to the CP – violating phase of the weak decay amplitude into I=1 final states. This decay has not been observed so far, and the best upper limit on the branching ratio BR(KS → 3π0) < 1.2 · 10−7 is two orders of magnitude larger than predictions based on the Standard Model. In this article we present the search for the KS → 3π0 decay performed with the KLOE detector operating at the DAΦNE ϕ – factory at the Frascati Laboratory. We describe the analysis techniques used for the background rejection and signal events selection leading to the result of an almost five times lower upper limit on the KS → 3π0 branching ratio. We also discuss the perspectives for a new measurement using the KLOE – 2 apparatus equipped with a new inner tracker and the calorimeters at low θ angle.
The KLOE – 2 Collaboration: D. Babusci, D. Badoni, I. Balwierz, G. Bencivenni, C. Bini, C. Bloise, V. Bocci, F. Bossi, P. Branchini, A. Budano, L. Caldeira Balkeståhl, G. Capon, F. Ceradini, P. Ciambrone, E. Czerwiński, E. Dané, E. De Lucia, G. De Robertis, A. De Santis, A. Di Domenico, C. Di Donato, R. Di Salvo, D. Domenici, O. Erriquez, G. Fanizzi, A. Fantini, G. Felici, S. Fiore, P. Franzini, P. Gauzzi, G. Giardina, S. Giovannella, F. Gonnella E. Graziani, F. Happacher, B. Höistad, L. Iafolla, E. Iarocci, M. Jacewicz, T. Johansson, A. Kupsc, J. Lee-Franzini, B. Leverington, F. Loddo, S. Loffedo, G. Mandaglio, M. Martemianov, M. Martini, M. Mascolo, R. Messi, S. Miscetti, G. Morello, D. Moricciani, P. Moskal, F. Nguyen, A. Passeri, V. Patera, I. Prado Longhi, A. Ranieri, C. F. Redmer, P. Santangelo, I. Sarra, M. Schioppa, B. Sciascia, M. Silarski, C. Taccini, L. Tortora, G. Venanzoni, R. Versaci, W. Wiślicki, M. Wolke, J. Zdebik
© Owned by the authors, published by EDP Sciences, 2012
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