We measure the time-dependent CP violation in B0 → KS0KS0KS0 decay using 772×106 BB pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e− collider. This decay mode occurs via b → s quark transition which is prohibited in the standard model and it is sensitive to new physics. The measured S (−sin2φ1) and A are -0.652 ± 0.215(stat) ± 0.046(syst) and 0.185 ± 0.162(stat) ± 0.042(syst), respectively. The results are consistent with world average value in PDG with standard model expectation.
Thesis Advisor: Prof. Hwanbae Park