arXiv subjects

G. Saracino

Publications and source records attributed to G. Saracino.

24 records · Page 2Linked to original sources

arXiv2007

A prototype large-angle photon veto detector for the P326 experiment at CERN

The P326 experiment at the CERN SPS has been proposed with the purpose of measuring the branching ratio for the decay K^+ \to π^+ ν\barν to within 10%. The photon veto system must provide a rejection factor of 10^8 for π^0 decays. We have explored two designs for the large-angle veto detectors, one based on scintillating tiles and the other using scintillating fibers. We have constructed a prototype module based on the fiber solution and evaluated its performance using low-energy electron beams from the Frascati Beam-Test Facility. For comparison, we have also tested a tile prototype constructed for the CKM experiment, as well as lead-glass modules from the OPAL electromagnetic barrel calorimeter. We present results on the linearity, energy resolution, and time resolution obtained with the fiber prototype, and compare the detection efficiency for electrons obtained with all three instruments.

physics.ins-det↗

arXiv2007

Precise measurements of the eta and the neutral kaon meson masses with the KLOE detector

We present precise measurements of the eta and K0 masses using the processes phi to eta gamma, eta to gamma gamma and phi to Ks Kl, Ks to pi+ pi-. The K0 mass measurement, M_K=497.583 +/- 0.005 (stat) +/- 0.020 (syst) MeV, is in acceptable agreement with the previous measurements but is more accurate. We find m(eta) = 547.874 +/- 0.007 (stat) +/- 0.031 (syst) MeV. Our value is the most accurate to date and is in agreement with two recent measurements based on eta decays, but is inconsistent, by about 10 sigma, with a measurement of comparable precision based on eta production at threshold.

hep-ex↗

arXiv2007

Measurement of the slope parameter αfor the η\to 3π^0 decay at KLOE

We report a preliminary measurement of the slope parameter $α$ for the $η\to 3\piz$ decay carried out with KLOE at DA$Φ$NE; where $α$ is the parameter describing the energy dependence of the square of the matrix element for this decay. By fitting the event density in the Dalitz plot with a collected statistic of 420 pb$^{-1}$ we determine $α= -0.027 \pm 0.004 (stat) ^{+0.004}_{-0.006} (syst)$. This result is consistent with current chiral perturbation theory calculations within the unitary approach.

hep-ex↗

arXiv2007

Determination of the η\toπ^+π^-π^0 Dalitz Plot slopes and asymmetries with the KLOE detector

We have studied, with the KLOE detector at the DA$Φ$NE $Φ$-Factory, the dynamics of the decay $η\toπ^+π^-π^0$ using data from the radiative $ϕ\toηγ$ decay for an integrated luminosity $L = 450 \textrm{pb^{-1}}$. From a fit to the Dalitz plot density distribution we obtain a precise measurement of the slope parameters. This should allow to improve the knowledge of the decay amplitude which is sensitive to the u-d quark mass difference. We also present new best results on the C-violating asymmetries in the $η\toπ^+π^-π^0$ decay.

hep-ex↗

arXiv2007

Charged kaon lifetime at KLOE

Preliminary result on the charged kaon lifetime, obtained by the KLOE experiment operating at DA$Φ$NE, the Frascati $ϕ$-factory, is presented

hep-ex↗

arXiv2007

eta Physics and phi Radiative Decays at Kloe

Here we present KLOE results on the phi meson decays in pi0 pi0 gamma, pi+ pi- gamma and eta pi0 gamma, the measurement of the ratio Br(phi to eta' gamma)/Br(phi to eta gamma) with the estimate of the eta' gluonium content and the measurement of the eta mass.

hep-ex↗