ETD

• asymmetry
• BelleII
• charm
• cp
• meson
• physics
• violation

The goal of this work is to evaluate the sensitivity to CP violation in the decay D0 → π+π−π0 at BelleII, to assess the prospects for measuring it in the following years. The Dalitz plot (DP) is the key tool for studying such three-body decays. It is a phase-space representation in which the variables are the square of the invariant masses of final-state particle pairs. Its sensitivity to both weak and strong phases makes it possible to reveal CP violation in regions of the phase space, where global averaging could otherwise wash out the effect.
The observable sensitive to CPV that I have used is the CP asymmetry, defined as the ratio between the difference and the sum of the number of correctly reconstructed D0 and anti-D0 decays. To identify the regions of the DP that are more sensitive to CPV, I have analysed a recent article by A. Dery et al., which predicts the value of the CP asymmetry on the DP. The CP asymmetry prediction is based on a DeltaU=0 rule theory, which affirms that decays with a null variation of U-spin are favoured with respect to decays with DeltaU=1.
My analysis is based on the simulated dataset produced by the BelleII collaboration. The estimation of the statistical sensitivity is the main focus of this work. After applying the selection criteria, I conducted an initial study to assess the reconstruction efficiency in different portions of the Dalitz plot. I examined the reconstruction efficiency in terms of the kinematic variables of the decay. Then, I have evaluated the statistical uncertainty of the average predicted asymmetry in the specific portions of the Dalitz plot. I extrapolated it for different values of integrated luminosity to determine the significance of the expected measurement.