Measurement of the Dalitz plot slope parameters for K−→π0π0π− decay using ISTRA+ detector

The Dalitz plot slope parameters g, h and k for the K−→π0π0π− decay have been measured using in-flight decays detected with the ISTRA+ setup operating in the 25 GeV negative secondary beam of the U-70 PS. About 252 K events with four-momenta measured for the π− and four involved photons were used for the analysis. The values obtained g=0.627±0.004(stat)±0.010(syst), h=0.046±0.004(stat)±0.012(syst), k=0.001±0.001(stat)±0.002(syst) are consistent with the world averages dominated by K+ data, but have significantly smaller errors.