The direct CP violation parameter Re(epsilon'/epsilon) has been measured from the decay rates of neutral kaons into two pions using the NA48 detector at the CERN SPS. The 2001 running period was devoted to collecting additional data under varied conditions compared to earlier years (1997-1999). The new data yield the result: Re(epsilon'/epsilon) = (13.7 +/- 3.1) x 10(-4). Combining this result with that published from the 1997, 98 and 99 data, an overall value of Re(epsilon'/epsilon) = (14.7 +/- 2.2) x 10(-4) is obtained from the NA48 experiment. (C) 2002 Elsevier Science B.V. All rights reserved

The beam and detector, used for the NA48 experiment, devoted to the measurement of Re(epsilon'/epsilon) and for the NA48/1 experiment on rare KS and neutral hyperon decays, are described

The SPEC[1] CINT benchmark has been used as a performance reference for computing in the HEP community for the past 20 years. The SPECint_base2000 (SI2K) unit of performance has been used by the major HEP experiments both in the Computing Technical Design Report for the LHC experiments and in the evaluation of the Computing Centres. At recent HEPiX[3] meetings several HEP sites have reported disagreements between actual machine performances and the scores reported by SPEC. Our group performed a detailed comparison of Simulation and Reconstruction code performances from the four LHC experiments in order to find a successor to the SI2K benchmark. We analyzed the new benchmarks from SPEC CPU2006 suite, both integer and floating point, in order to find the best agreement with the HEP code behaviour, with particular attention paid to reproducing the actual environment of HEP farm i.e., each job running independently on each core, and matching compiler, optimization, percentage of integer and floating point operations, and ease of use.

A search for the decay K S → π 0 e + e − has been made by the NA48/1 experiment at the CERN SPS accelerator. Using data collected during 89 days in 2002 with a high-intensity K S beam, 7 events were found with a background of 0.15 events. The branching fraction BR(K S → π 0 e + e − , m ee > 0.165 GeV/c 2 ) = (3.0 +1.5 −1.2 (stat) ± 0.2(syst)) × 10 −9 has been measured. Using a vector matrix element and a form factor equal to one, the measurement gives BR(K S → π 0 e + e − ) = (5.8 +2.9 −2.4 ) × 10 −9 .

New measurements of the eta and K-0 masses have been performed using decays to 3pi(0) with the NA48 detector at the CERN SPS. Using symmetric decays to reduce systematic effects, the results M(eta) = 547.843 +/- 0.051 MeV/c(2) and M(K-0) = 497.625 +/- 0.031 MeV/c(2) were obtained