Hikaru Tanigawa ; Yutaka Ushiroda

2022
University of Tokyo Tokyo

Abstract: B0 → KS0 KS0 KS0 decay is mediated by b → sqq penguin transition within the Standard Model. Comparison of CP-violating parameters between the penguin-dominated decays and b → ccs decays such as B0 → J/ψKS0 provides a probe for new physics which contributes to the b → s transition. We report a measurement of time-dependent CP violation in B0 → KS0 KS0 KS0 decays, using a data set containing 198 × 10^6 BB pairs collected at the Belle II experiment from 2019 to 2021. We obtain S = −1.86+0.91-0.46(stat) ± 0.09(syst), and A = −0.22+0.30-0.27(stat) ± 0.04(syst). The result is consistent with the SM expectation (S, A) = (−0.70 ± 0.02, 0) based on the measurements in B0 → (cc)K0 and the previous measurements at Belle, BaBar, and Belle II. We have established the analysis procedure anticipating the high-precision measurement using 50 ab−1 data to be taken at the Belle II experiment.

Note: Presented on 21 07 2022
Note: PhD