Measurements of the charge asymmetry of the Dalitz plot parameters for $K^{\pm}\to\pi^{\pm}\pi^0\pi^0$ decays

Abstract

Measurements of the Charge Asymmetry of the Dalitz Plot Parameters for Decays AbstractThe charge asymmetry of the g, h, and k Dalitz plot parameters for K ± → π ± π 0 π 0 decays has been measured with 35 GeV/c hadron beams at the 70 GeV IHEP accelerator. The g, h, and k values obtained appear to be identical for K ± decays within the errors quoted. In particular, the charge asymmetry A g = (g + −g − )/(g + + g − ) of the slope g is equal to (0.2 ± 1.9) · 10 −3 .

Measurements of the Dalitz plot parameters for K ± → π±π0π0 decays

“…It is shown in our paper [5] that the event distributions in the Dalitz plots for K + and K − decays are identical. Taking this into account we used combined statistics for K ± → π ± π 0 π 0 decays to estimate the Dalitz plot parameters.…”

“…For example, the difference of the Dalitz plot slopes g obtained in [2] and [3] is equal to 0.109 ± 0.021. As shown by our data [5] this result cannot be explained by CP violation and is most probably due to underestimation of systematic uncertainties. In this paper we present new results on the Dalitz plot parameters based on the analysis of 493k events of K ± → π ± π 0 π 0 decays collected with the TNF-IHEP facility [5,6].…”

“…Due to the finite setup resolution on the u and v variables [5] the 'measured' u ′ , v ′ values can differ from the true u, v for both experimental and MC events. To take this into account the Dalitz plot parameters were estimated by minimizing the following functional form:…”

“…The Level 2 trigger required more than 0.8 GeV energy deposition in at least three trigger elements of the GEPARD. The details of the setup and measurement procedure can be found elsewhere [5].…”

Kaon Physics at CERN: Recent Results by NA48/2 Experiment

“…The best present measurement are [6] A c g =(22 ± 15 ± 37) · 10 −4 (prelim.) and [7] A n g =(2 ± 19) · 10 −4 based on 54 · 10 6 and 620 · 10 3 events respectively.…”