Search for CP violation in decays at Belle

We report on a search for CP violation in decays using a data sample of 699 fb−1 collected in the Belle experiment at the KEKB electron-positron asymmetric-energy collider. The CP asymmetry is measured in four bins of the invariant mass of the system and found to be compatible with zero with a precision of O(10−3) in each mass bin. Limits for the CP violation parameter ℑ(ηS) are given at a 90% confidence level. These limits are |ℑ(ηS)|<0.026 or better, depending on the parameterization used to describe the hadronic form factors and improve upon previous limits by one order of magnitude.