CP Violation Search in $\tau \to \pi {\pi }^0{\nu }_{\tau }$ Decays

Abstract

Using a sample of 12.2 million $\tau$-lepton pairs produced by $e^{+}{e}^{-}$ annihilation at $\sqrt{s}\sim 10.6$GeV and collected by the CLEO detector, we search for and set limits on CP violation in $\tau$-lepton decays. For each event, we require that both $\tau$-leptons decay via the mode $\tau \text{ra}\pi {\pi }^0\nu$. The search is performed within the context of a multi-Higgs Doublet Model and the imaginary part of the coupling constant parameterizing the non-Standard Model diagram leading to CP violation is constrained to be $-0.046<\Im (\Lambda )<0.022$ at 90% CL. The novel search technique is of general utility.

Comments: 4 pages, 7 figures, 1 table. Conference proceeding for BCP4, 19-23 February 2001, Ise-Shima, Japan