Search for CP violation in ZmFττ

ALEPH Collaboration (1992) Search for CP violation in ZmFττ. Physics Letters B, 297 (3-4). pp. 459-468. ISSN 0370-2693

Abstract

Using the 18.8 pb−1 of data accumulated at LEP in 1990 and 1991 with the ALEPH detector, a direct test of neutral current CP-invariance is performed by a search for CP-odd correlations in Z decays to τ pairs where both τ decay modes are identified. No evidence for CP-violation is observed. The weak dipole moment of the τ has been measured to be dτ(mZ) = (1.3 ± 1.4 ± 0.1) × 10−17e·cm which results in an upper limit on the weak dipole moment of |dτ(mZ)| ⩽ 3.7 × 10−17e·cm with 95% confidence level.