Lepton Flavor Violation in the Higgs Boson Decay at a Linear Collider

Abstract

We study possibility of observing the process $h^0\to {\tau }^{\pm }{\mu }^{\mp }$ at a linear collider. The branching ratio is constrained to be of the order of $10^{-4}$ by the ${\tau }^{-}\to {\mu }^{-}\eta$ result. Supersymmetric standard models can reproduce such amount of the branching ratio by taking a specific parameter set. The Higgsstrahlung process $e^{+}{e}^{-}\to Z{h}^0$ is preferable because of its simple kinematic structure, then, the signal process is $e^{+}{e}^{-}\to Z{h}^0\to Z{\tau }^{\pm }{\mu }^{\mp }$. The most serious background comes from the process, $e^{+}{e}^{-}\to Z{h}^0\to Z{\tau }^{\pm }{\tau }^{\mp }\to {\tau }^{\pm }{\mu }^{\mp }\nu \bar{\nu }$. We estimate the significance of the signal, taking into account the background reduction.

Comments: Proceedings for the Linear Collider Workshop (LCWS2004) in Paris, France, April 19-23, 2004, Talk given by T. Ota, 4 pages, 2 figures