Study of KSKL coupled decays and KL-Be interactions with the CMD-2 detector at VEPP-2M collider

Abstract An integrated luminosity ≈ 4000 nb −1 of around F meson mass (5.0 × 10 6 of F's) has been collected with the CMD-2 detector at the VEPP-2M collider. The latest analysis of the K S K L coupled decays based on 30% of available data is presented in this paper. The K S K L pairs from F decays were reconstructed in the drift chamber when both kaons decayed into two charged particles. From a sample of 1423 coupled decays a selection of candidates for the CP-violating K L → π + π − decay was performed. CP-violating decays were not identified because of the dominance of events with a K L regenerating at the Be beam pipe into K S and a background from K L semileptonic decays. The regeneration cross section of 110 MeV/ c K L 's was found to be σ reg Be = 53 ± 17 mb, in agreement with theoretical expectations. The angular distribution of K S 's after regeneration and the total cross section of K L for Be have been measured.