Eι decay to KKπ in pp annihilation at rest

Abstract The results of the analysis of 3940 (K K π)ππ events from a sample of 18 millions p p annihilations in the liquid hydrogen target of the OBELIX spectrometer at LEAR (CERN) are presented. The presence of two pseudoscalar states at 1.416±0.002GeV/ c 2 , with width 0.050±0.004GeV/ c 2 , and at 1.46±0.01GeV/ c 2 , with width 0.105±0.015GeV/ c 2 , is established. The lighter mass resonance decays mainly to K K π , possibly with final state interactions and a small contribution coming from a 0 π . The higher mass 0 −+ state, which is seen for the first time in p p annihilation at rest, decays only to K ∗ K . Masses, widths and decay modes are in agreement with the analysis of J Ψ radiative decay performed by the Mark III Collaboration. From the fit the G -parity was determined to be +1. The dominant three-body decay mode of the lighter pseudoscalar is observed for the first time in this measurement.