M. Pepe

Performance of an electromagnetic liquid krypton calorimeter based on a ribbon electrode tower structure

The NA48 collaboration is preparing a new experiment at CERN aiming to study CP violation in the K0-K0 system with an accuracy of 2 × 10−4 in the parameter Re(ϵ′/ϵ). Decays in two π0s will be recorded by a quasi-homogeneous liquid krypton calorimeter. A liquid krypton calorimeter has been chosen to combine good energy, position and time resolution with precise charge calibration and long-term stability. The prototype calorimeter incorporating the final design of the electrode read-out structure is presented in this paper. An energy resolution of ≃3.5%√E with a constant term smaller than 0.5% has been obtained. The time resolution was found to be better than 300 ps above 15 GeV.

Measurement of the s**(1/2) Dependence of Jet Production at the CERN anti-p p Collider

Abstract The production of very large transverse momentum ( p T ) hadron jets has been measured in the UA2 experiment at the CERN p p Collider for s =630 GeV . The inclusive jet production cross sections exhibit a p T -dependent increase with respect to the s =546 GeV data from previous Collider runs. This increase can be described both by QCD calculations and by approximate x T =2 p T /√ s scaling. No significant deviation of the data from QCD predictions is observed at very large p T , placing a lower limit on the characteristic scale Λ c of a hypothetical superstrong contact interaction responsible for the binding of preons in the quark ( Λ c >370 GeV at 95% CL).

Direct Photon Production at the {CERN}

Abstract Using the UA2 apparatus, the inclusive cross section has been measured for production of high- p T direct photons in pp collisions at s =546 GeV and s =630 GeV . The results are in good agreement with QCD predictions.

\bar{p} p

AbstractWe have measured the lifetime of charged and neutralD mesons using high resolution silicon strip detectors in the NA11 spectrometer at the CERN SPS. TheD mesons were produced in 200 GeV π− interactions. We obtain a value of

Measurement of the lifetime of charged and neutralD mesons with high resolution silicon strip detectors

\tau _{D^ \pm } = \left( {10.6\begin{array}{*{20}c} { + 3.6} \\ { - 2.4} \\ \end{array} } \right) \cdot 10^{ - 13} s

PERFORMANCE OF AN ELECTROMAGNETIC LIQUID KRYPTON CALORIMETER

based on 28, and

Lifetimes of charged and neutralD mesons

\tau _{D^0 } = \left( {3.7\begin{array}{*{20}c} { + 1.0} \\ { - 0.7} \\ \end{array} } \right) \cdot 10^{ - 13} s