The Beam and Detector for a High Precision Measurement of {CP} Violation in Neutral Kaon Decays

Abstract The K 0 beam and detector used for a high-precision measurement of the CP-violation parameter ϵ′ at the CERN Super Proton Synchrotron (SPS) are described. The beam provides K L and K S alternately through a common decay region. The detection of the decays is based on wire chambers and calorimeters without employing a magnet. The trigger and readout system achieve a high selectively for the suppressed, CP-violating, two-pion decays of the K L by incorporation of hard-wired processors. The readout is based on Fastbus for maximum data rates.