Pion-pion scattering lengths from Ke4 and Cusp at NA48/2 experiment
نویسنده
چکیده
π + π − e ± ν (Ke4) decay. Thanks to the absence of other hadrons in the final state the ππ interaction can be analyzed in terms of phase shift variation with the ππ invariant mass. The preliminary results on a set of ∼ 1150000 K events collected in two years of data taking, will be discussed. The second way to evaluate the ππ scattering lengths is based on the accurate study of K → πππ Dalitz plot, in which the strong rescattering process
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