ISSN - 00319007, EISSN - 10797114, Physical Review Letters, 2011, vol. 107, p. -
Search for CP violation in τ±→KS0π ±ντ decays at Belle
We report on a search for CP violation in τ±→ KS0π±ντ decays using a data sample of 699fb-1 collected by 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 KS0π± 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 Im(ηS) are given at the 90% confidence level. These limits are |Im(ηS)|<0.026 or better, depending on the parametrization used to describe the hadronic form factors, and improve upon previous limits by 1 order of magnitude. © 2011 American Physical Society.