A measurement of the CP-conserving component of the decay KS0→π+π−π0

The NA48 Collaboration has measured the amplitude of the CP-conserving component of the decay KS0→π+π−π0 relative to KL0→π+π−π0. For the characteristic parameter λ, the values Reλ=0.038±0.010 and Imλ=−0.013±0.007 have been extracted. These values agree with earlier measurements and with theoretical predictions from chiral perturbation theory.