Search for R-Parity Violating Production of Single Sneutrinos in e + e − Collisions at √

A search for single sneutrino production under the assumption that R-parity is violated via a single dominant LLĒ coupling is presented. This search considers the process eγ → ν̃` and is performed using the data collected by the ALEPH detector at centre-ofmass energies from 189 GeV up to 209 GeV corresponding to an integrated luminosity of 637.1 pb−1. The numbers of observed candidate events are in agreement with Standard Model expectations and 95% confidence level upper limits on five of the LLĒ couplings are given as a function of the assumed sneutrino mass. Submitted to European Physical Journal C ——————————————– ∗) See next pages for the list of authors