Impact of bosonic decays on the search for (τ)over-bar2 and (ν)over-barτ

We perform a detailed study of the decays of the heavier tau slepton (<(tau)over tilde>(2)) and tau-sneutrino (<(nu)over tilde>(r)) in the Minimal Supersymmetric Standard Model (MSSM). We show that the decays into Higgs or gauge bosons, i.e. <(tau)over tilde>(-)(2) --> <(tau)over tilde>(-)(1) + (h(0), H-0, A(0) or Z(0)), <(tau)over tilde>(-)(2) --> <(nu)over tilde>(tau) (H- or W-), and <(nu)over tilde>(tau) --> <(tau)over tilde>(-)(1) + (H+ or W+), can be very important due to the sizable tau Yukawa coupling and large mixing parameters of <(tau)over tilde>. Compared to the decays into fermions, such as <(tau)over tilde>(-)(2) --> tau(-) + <(chi)over tilde>(0)(i) and <(tau)over tilde>(-)(2) --> nu(tau) + <(chi)over tilde>(-)(j), these bosonic decay modes can have significantly different decay distributions. This could have an important influence on the search for <(tau)over tilde>(2) and <(nu)over tilde>(tau) and the determination of the MSSM parameters at future colliders. (C) 1999 Published by Elsevier Science B.V. All rights reserved.