Latest Results in Kaon Physics on the KLOE Data and Status of Analysis of the KLOE-2 Data

Abstract

The KLOE-2 Collaboration concluded its data-taking at the DA$\Phi$NE $\phi$-factory of the Laboratori Nazionali di Frascati of INFN, collecting 5.5 fb$^{-1}$ of data at the center of mass energy corresponding to the mass of the $\phi$(1020). This sample together with the 2.5 fb$^{-1}$ collected by the KLOE Collaboration until 2006 constitutes the largest sample in the world collected at the peak of the $\phi$ resonance. With the kaons produced in the decay $\phi \rightarrow K_SK_L$ it is possible to perform very precise test of the discrete symmetries T, CP, and CPT, and moreover the entanglement of the neutral kaons can be exploited to perform unique tests of quantum mechanics. Also large samples of $\eta$ mesons are produced in $\phi$ radiative decays, allowing to study the rare decays of this meson. KLOE-2 has also installed two tagging devices for electrons and positrons scattered in $\gamma \gamma$ processes, with the main goal to study the single $\pi ^0$ production. Search of new vector bosons in the hidden dark sector is also performed with the KLOE/KLOE-2 data. An information about the latest results with KLOE data on CPT test with charge asymmetry of $K_S$ semileptonic decays and a preliminary result on the CPT test in transitions is given.

Eryk Czerwiński—On behalf of KLOE-2 collaboration.