Hyperfine Interactions

, 239:53 | Cite as

Tests of discrete symmetries with the neutral kaon system at the KLOE and KLOE-2 experiments

  • Aleksander GajosEmail author
  • KLOE-2 Collaboration
Open Access
Part of the following topical collections:
  1. Proceedings of the 7th Symposium on Symmetries in Subatomic Physics (SSP 2018), Aachen, Germany, 10–15 June 2018


The KLOE-2 experiment continues and extends the program of its predecessor KLOE in the field of discrete symmetry tests with the K meson system, among other studies which comprise light meson spectroscopy, dark matter searches and γγ physics. Together, KLOE and KLOE-2 have recorded the largest sample (almost 8 fb− 1) of e+e collisions at the energy equal to ϕ meson mass, amounting to 2.4 × 1010 of produced ϕ mesons. We report on the latest results and ongoing analyses of KLOE and KLOE-2 concerning discrete symmetry tests and measurements of symmetry-violating observables. A measurement of the CPT violation sensitive asymmetry in semileptonic decays of K˙S with 1.7 fb− 1 of KLOE data will be presented, which improves the sensitivity w.r.t. previous measurements about twice. Moreover, status of direct tests of T and CPT in transitions of neutral kaons performed with the ϕ →K˙SK˙L → πeν, 3π0(2π) processes will be reported, followed by the search of the CP-violating decay K˙S → 3π0 using the data recently acquired by KLOE-2.


Discrete symmetries CPT CP Neutral kaons 



We warmly thank our former KLOE colleagues for the access to the data collected during the KLOE data taking campaign. We thank the DAΦNE team for their efforts in maintaining low background running conditions and their collaboration during all data taking. We want to thank our technical staff: G.F. Fortugno and F. Sborzacchi for their dedication in ensuring efficient operation of the KLOE computing facilities; M. Anelli for his continuous attention to the gas system and detector safety; A. Balla, M. Gatta, G. Corradi and G. Papalino for electronics maintenance; C. Piscitelli for his help during major maintenance periods. This work was supported in part by the Polish National Science Centre through the Grants No. 2013/11/B/ST2/04245, 2014/14/E/ST2/00262, 2014/12/S/ST2/00459, 2016/21/N/ST2/01727, 2016/23/N/ST2/01293, 2017/26/M/ST2/00697.


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Authors and Affiliations

  1. 1.Institute of PhysicsJagiellonian UniversityCracowPoland

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