Measurement of CP-violation asymmetries in D0 to Ks pi+ pi-

TL;DR

This study measures CP-violation asymmetries in the three-body decay D0 to Ks pi+ pi- using data from the Tevatron, employing Dalitz analysis techniques, and finds results consistent with no CP violation, aligning with standard model expectations.

Contribution

It presents the first comprehensive Dalitz-plot analysis of CP asymmetries in D0 to Ks pi+ pi- decays using Tevatron data, combining isobar and model-independent methods.

Findings

No significant CP-violation observed.

Measured asymmetry ACP = (-0.05 +- 0.57 (stat) +- 0.54 (syst))%.

Results consistent with standard model predictions.

Abstract

We report a measurement of time-integrated CP-violation asymmetries in the resonant substructure of the three-body decay D0 to Ks pi+ pi- using CDF II data corresponding to 6.0 invfb of integrated luminosity from Tevatron ppbar collisions at sqrt(s) = 1.96 TeV. The charm mesons used in this analysis come from D*+(2010) to D0 pi+ and D*-(2010) to D0bar pi-, where the production flavor of the charm meson is determined by the charge of the accompanying pion. We apply a Dalitz-amplitude analysis for the description of the dynamic decay structure and use two complementary approaches, namely a full Dalitz-plot fit employing the isobar model for the contributing resonances and a model-independent bin-by-bin comparison of the D0 and D0bar Dalitz plots. We find no CP-violation effects and measure an asymmetry of ACP = (-0.05 +- 0.57 (stat) +- 0.54 (syst))% for the overall integrated CP-violation asymmetry, consistent with the standard model prediction.