Neutralino phenomenology at LEP2 in supersymmetry with bilinear breaking of R-parity

We discuss the phenomenology of the Lightest neutralino in models where an effective bilinear term in the superpotential parametrizes the explicit bre aking of R-parity. We consider supergravity scenarios where the lightest su persymmetric particle (LSP) is the lightest neutralino and which can be exp lored at LEP2. We present a detailed study of the LSP decay properties and general features of the corresponding signals expected at LEP2. We also con trast our model with gauge mediated supersymmetry breaking. (C) 2001 Elsevi er Science B.V. All rights reserved,