Study of the Dalitz decay ϕ→ηe+e- with the KLOE detector

We have studied the vector to pseudoscalar conversion decay ϕ→ηe+e-, with η→π0π0π0, with the KLOE detector at DAΦNE. The data set of 1.7 fb-1 of e+e- collisions at s~Mϕ contains a clear conversion decay signal of ~31, 000 events from which we measured a value of BR(ϕ→ηe+e-)=(1.075±0.007±0.038)×10-4. The same sample is used to determine the transition form factor by a fit to the e+e- invariant mass spectrum, obtaining bϕη=(1.28±0.10-0.08+0.09) GeV-2, that improves by a factor of five the precision of the previous measurement and is in good agreement with VMD expectations

Test of CPT and Lorentz symmetry in entangled neutral kaons with the KLOE experiment

Neutral kaon pairs produced in phi decays in anti-symmetric entangled state can be exploited to search for violation of CPT symmetry and Lorentz invariance. We present an analysis of the CP-violating process phi -> KSKL -> pi(+)pi(-)pi(+)pi(-) based on 1.7 fb(-1) of data collected by the KLOE experiment at the Frascati phi-factory DA Phi NE. The data are used to perform a Measurement of the CPT-violating parameters Delta a(mu) for neutral kaons in the context of the Standard Model Extension framework. The parameters measured in the reference frame of the fixed stars are:Delta a(0) = (-6.0 +/- 7.7(stat)+/- 3.1(syst)) X 10(-18) GeV,Delta a(x) = (0.9 +/- 1.5(stat)+/- 0.6(syst)) X 10(-18) GeV,Delta a(y) = (-2.0 +/- 1.5(stat)+/- 0.5(syst)) X 10(-18) GeV,Delta a(z) = (3.1 +/- 1.7(stat)+/- 0.5(syst)) X 10(-18) GeV.These are presently the most precise measurements in the quark sector of the Standard Model Extension. (C) 2014 The Authors. Published by Elsevier B.V

Test of CPT and Lorentz symmetry in entangled neutral kaons with the KLOE experiment

Neutral kaon pairs produced in Ï\u86 decays in anti-symmetric entangled state can be exploited to search for violation of CPT symmetry and Lorentz invariance. We present an analysis of the CP-violating process Ï\u86 â\u86\u92 KSKL â\u86\u92 Ï\u80 +Ï\u80 -Ï\u80 +Ï\u80 - based on 1.7 fb -1 of data collected by the KLOE experiment at the Frascati Ï\u86-factory DAΦNE. The data are used to perform a measurement of the CPT-violating parameters δaμ for neutral kaons in the context of the Standard Model Extension framework. The parameters measured in the reference frame of the fixed stars are:δa0=(-6.0±7.7stat±3.1syst)Ã\u9710-18 GeV,δaX=(0.9±1.5stat±0.6syst)Ã\u9710-18 GeV,δaY=(-2.0±1.5stat±0.5syst)Ã\u9710-18 GeV,δaZ=(3.1±1.7stat±0.5syst)Ã\u9710-18 GeV. These are presently the most precise measurements in the quark sector of the Standard Model Extension. © 2014 The Authors