Determination of the S-wave π π scattering lengths from a study of K ±→π ± π 0 π 0 decays

Determination of the S - wave ππ scattering lengths from a study of K ± → π ± π 0 π 0 decays

We report the results from a study of the full sample of ∼ 6.031 × 10 K → πππ decays recorded by the NA48/2 experiment at the CERN SPS. As first observed in this experiment, the ππ invariant mass (M00) distribution shows a cusp-like anomaly in the region around M00 = 2m+, where m+ is the charged pion mass. This anomaly has been interpreted as an effect due mainly to the final state charge excha...

Measurement of Γ ( K S → π + π − ( γ ) ) / Γ ( K S → π 0 π 0 )

We have measured the ratio R S = Γ(KS → π π(γ))/Γ(KS → π π) with the KLOE detector at the DAΦNE ee collider. This measurement is fully inclusive with respect to the ππγ final state. The sample of over 10 two-pion decays of tagged KS mesons allows a statistical error as low as ∼ 0.1% to be obtained. The accuracy is limited by systematic uncertainties, which are estimated primarily from data. We ...

0 Determination of γ from B̄ 0 → K − π + , π − π + Decays

We show that large electroweak penguin effects invalidate previously suggested methods to constraint and to determine the CP violating phase γ of the KM matrix using B̄0 → K−π+, π−π+ and B → K̄0π− decays. We obtain new results on the constraint and the determination of γ. It is found that present central values of experimental data on these decays exclude the range between 0.57 and 0.87 for γ whi...

Results from NA 48 / 2 on ππ scattering lengths measurements in K ± → π + π − e ± ν and K ± → π 0 π 0 π ± decays

Search for direct CP violating charge asymmetries in K ± → π ± π + π − and K ± → π ± π 0 π 0 decays

A measurement of the direct CP violating charge asymmetries of the Dalitz plot linear slopes Ag = (g + − g)/(g + g) in K → πππ and K → πππ decays by the NA48/2 experiment at CERN SPS is presented. A new technique of asymmetry measurement involving simultaneous K and K beams and a large data sample collected allowed a result of an unprecedented precision. The charge asymmetries were measured to ...