C. Bacci

Performance of a uranium/tetramethylpentane electromagnetic and hadronic calorimeter

We present results from the barrel depleted uranium/TMP calorimeter modules constructed by the UA1 Collaboration. Electromagnetic and hadronic energy resolutions have been measured using electron and pion beams with momenta in the range 7 to 70 GeV/c. Results on the energy linearity and the spatial uniformity of response are reported. The electromagnetic shower position resolution has been measured as a function of energy using a fine grained position detector placed at a depth of − 3.5small chi, Greek0. The noise arising both from the electronics chain and from the uranium radioactivity is compared with 70 GeV/c muon signals. The ratio of the electron to pion response has been measured both as a function of the energy and of the electric field. The high lateral and longitudinal granularity of the calorimeter and the presence of a position detector have been used to determine the electron pion separation as a function of energy.

KLOE measurement of the charged kaon absolute semileptonic BR's

The KLOE Collaboration F. Ambrosino, A. Antonelli, M. Antonelli, F. Archilli, C. Bacci, P. Beltrame, G. Bencivenni, S. Bertolucci, C. Bini, C. Bloise, S. Bocchetta, V. Bocci, F. Bossi, P. Branchini, R. Caloi, P. Campana, G. Capon, T. Capussela, F. Ceradini, S. Chi, G. Chiefari, P. Ciambrone, E. De Lucia, A. De Santis, P. De Simone, G. De Zorzi, A. Denig, A. Di Domenico, C. Di Donato, S. Di Falco, B. Di Micco, A. Doria, M. Dreucci, G. Felici, A. Ferrari, M. L. Ferrer, G. Finocchiaro, S. Fiore, C. Forti, P. Franzini, C. Gatti, P. Gauzzi, S. Giovannella, E. Gorini, E. Graziani, M. Incagli, W. Kluge, V. Kulikov, F. Lacava, G. Lanfranchi, J. Lee-Franzini, D. Leone, M. Martini, P. Massarotti, W. Mei, L. Meola, S. Miscetti, M. Moulson, S. Müller, F. Murtas, M. Napolitano, F. Nguyen, M. Palutan, E. Pasqualucci, A. Passeri, V. Patera, F. Perfetto, M. Primavera, P. Santangelo, G. Saracino, B. Sciascia,A. Sciubba, F. Scuri, I. Sfiligoi, A. Sibidanov, T. Spadaro, M. Testa, L. Tortora, P. Valente, B. Valeriani, G. Venanzoni, R. Versaci, G. Xu Correspondig author: B. Sciascia LNF INFN, barbara.sciascia@lnf.infn.it

Results with radiative events from KLOE

The KLOE experiment at the electron-positron collider DAΦNE has recently proven the feasibility of using initial state radiation (ISR) in e+e− annihilation for precision measurements of hadronic cross section. This new method, dubbed Radiative Return, allows us to measure hadronic cross sections for energies M2(hadron) < s at particle factories which operate at fixed centre-of-mass energy s. In the recently published KLOE measurement of the pion form factor, events had been collected where the ISR photon is emitted at small polar angles, which reduces the background from final state radiation (FSR) but leads to a suppression of the threshold region M2 ππ < 0.35 GeV2. We present here a complementary analysis using events with ISR photons emitted at large polar angles. Photon tagging is possible in this case (contrary to the small photon polar angle analysis) and the threshold region becomes accessible. Preliminary results are presented, as well as a measurement of the forward-backward asymmetry, which allows a test of the FSR model used for the description of the photon radiation from pions.

Latest results from KLOE at DAFNE

The KLOE experiment has finished its data taking at the e+e- collider DAΦNE in Frascati. KLOE has collected 2.5 fb-1 at the peak of the ϕ resonance, and 250 pb-1 at

Recent results from the KLOE experiment at DAPHNE

\sqrt{s}=1~{\rm GeV}

MEASUREMENT OF MOMENTUM AND ANGULAR DISTRIBUTION OF PUNCHTHROUGH MUONS AT THE RD5 EXPERIMENT

. The latest experimental results based on a sample of 450 pb-1 are presented in this paper: they mainly concern the neutral and charged kaon decays, and the radiative ϕ decays into scalar and pseudoscalar mesons.

Measurements of the form-factors slopes of

∼ 1. 3f b −1 from e+e− collisions at center-of-mass energy around the φ-meson peak, W ∼ 1.02 GeV. A selection of results obtained from a sample of 450 pb −1 of data acquired during year 2001 and 2002 is presented. Studying tagged KS and KL-mesons produced in the reaction e+e− → φ → KSKL we measured the branching ratio of the decay KS → πeν, the upper limit on the decay KS → π0π0π0 ,a nd the mainKL decay branching ratios. Exploiting the initial state radiation in the reaction e+e− → π+π−γ, we extracted the hadronic cross-section as a function of the squared center-of-mass energy sπ of the ππ system, in the range 0.35The KLOE experiment at DAΦNE collected about 450 pb−1 of data in 2001–2002. Much of this data set has been analyzed and has yielded definitive results on KS and radiative φ decays, as well as studies concerning a wide range of topics in kaon and hadronic physics.Recent results from the KLOE experiment at the DAΦNE e + e − collider are presented. KLOE has collected ∼ 500pb −1 of data in the years from 2000 to 2002. Preliminary results are obtained using wide samples of the full statistics and include: the BR of the Ke3 decay of the KS and the first measurement of its charge asymmetry, the ratio BR(KS → π + π − (γ))/BR(KS → π 0 π 0), the ratio BR(KL → γγ)/BR(KL → 3π 0), a detailed study of the decay φ → π + π − π 0 , the ratio BR(φ → η ′ γ)/BR(φ → ηγ) and the pseudoscalar mixing angle ϕP , the φ → f0γ and the φ → a0γ BRs.

K(L) \to \pi \mu \nu

Abstract The momentum and angular distributions of punchthrough muons have been measured after a 10 λ calorimeter using an iron toroid magnet with 1.5 T as spectrometer. The calorimeter was inside a variable magnetic field of 0 to 3 T. The incident momentum of the π − beam ranged from 20 to 300 GeV/ c . Measurements were also done at some beam momenta for π + , K + and p. The results are compared with Monte Carlo predictions. A parameterization for the momentum spectrum of punchthrough muons was derived from the data.