Search for neutral Higgs bosons decaying into four taus at LEP2

Abstract

A search for the production and non-standard decay of a Higgs boson, h, into four taus through intermediate pseudoscalars, a, is conducted on 683 pb−1 of data collected by the ALEPH experiment at centre-of-mass energies from 183 to 209 GeV. No excess of events above background is observed, and exclusion limits are placed on the combined production cross section times branching ratio, $ {\xi^2} = \frac{{\sigma \left( {{\text{e}^{+} }{\text{e}^{-} } \to {\text{Zh}}} \right)}}{{{\sigma_{\text{SM}}}\left( {{\text{e}^{+} }{\text{e}^{-} } \to {\text{Zh}}} \right)}} \times B\left( {h \to {\text{aa}}} \right) \times B{\left( {{\text{a}} \to {\tau^{+} }{\tau^{-} }} \right)^2} $ . For m h < 107 GeV/c 2 and 4 < m a < 10 GeV/c 2, ξ 2 > 1 is excluded at the 95% confidence level.