F. Ambrosino

First observation of quantum interference in the process Phi-->K(S) K(L) --> pi+ pi- pi+ pi-: A test of quantum mechanics and CPT symmetry

We present the first observation of quantum interference in the process phi ->KS KL ->pi+pi-pi+pi-. This analysis is based on data collected with the KLOE detector at the e^+e^- collider DAFNE in 2001--2002 for an integrated luminosity of about 380pb^-1. Fits to the distribution of Delta t, the difference between the two kaon decay times, allow tests of the validity of quantum mechanics and CPT symmetry. No deviations from the expectations of quantum mechanics and CPT symmetry have been observed. New or improved limits on various decoherence and CPT violation parameters have been obtained

Measurement of the branching ratio of the K-L ->pi(+) pi(-) decay with the KLOE detector

We present a measurement of the branching ratio of the CP violating decay KL->pi+pi- performed by the KLOE experiment at the phi factory DAFNE. We use 328 pb-1 of data collected in 2001 and 2002, corresponding to ~ 150 million tagged KL mesons. We find BR(KL->pi+pi-) =

Measurement of the branching ratio and search for a CP violating asymmetry in the eta ---> pi+ pi- e+ e-(gamma) decay at KLOE

(1.963 +/- 0.012 +/- 0.017)x 10^-3. This branching ratio measurement is fully inclusive of final-state radiation. Using the above result, we determine the modulus of the amplitude ratio |\eta_{+-}| to be (2.219 +/- 0.013)x 10^{-3} and |\epsilon| to be (2.216 +/- 0.013)x 10^{-3}.

Feasibility study of detection of high-Z material in nuclear waste storage facilities with atmosperic muons

We have studied the η→π+π−e+e−(γ)η→π+π−e+e−(γ) decay using about 1.7 fb−11.7 fb−1 collected by the KLOE experiment at the DAΦNE ϕ-factory. This corresponds to about 72 millions η mesons produced in ϕ radiative decays. We have measured the branching ratio, inclusive of radiative effects, with 4% accuracy: BR(η→π+π−e+e−(γ))=(26.8±0.9Stat.±0.7Syst.)×10−5BR(η→π+π−e+e−(γ))=(26.8±0.9Stat.±0.7Syst.)×10−5. We have obtained the first measurement of the CP-odd ππ–ee decay planes angular asymmetry, Aϕ=(−0.6±2.5Stat.±1.8Syst.)×10−2Aϕ=(−0.6±2.5Stat.±1.8Syst.)×10−2.

Measurement of σ(e+e−→π+π−) from threshold to 0.85 GeV2 using initial state radiation with the KLOE detector

Muon radiography is a well-established technique which is widely used in investigating the internal density structure of targets of different size and composition. Some examples of successful applications are the search for hidden chambers in archaeological sites and the monitoring of geological structures like volcanoes. The two main approaches to muon radiography are based on the effects of multiple Coulomb scattering and on absorption inside the target of atmospheric muons. The results of a Monte Carlo feasibility study of using muon radiography to investigate the presence of high-Z material (e.g. uranium) inside nuclear waste storage facilities using both the above mentioned techniques are presented. Albeit muon radiography has already been successfully applied to this kind of investigation in the past, this is the first time that it is benchmarked against the detection of cm-sized, high-Z samples inside building-sized storage facilities. For both multiple scattering and absorption approaches, preliminary results show that uranium samples of typical size greater than 5 cm can be detected inside a storage silo with a size of some meter filled with concrete, with a data taking period of several weeks. Smaller samples with size 2 cm are not detectable due to multiple scattering within the concrete matrix. The dependence of these results on the position of the samples and on the duration of data acquisition have been investigated and are reported as well, together with an estimate of the detection probability for fake signals.