The NOMAD experiment: a status report

NOMAD is an experiment searching for ν μ(e) → ν τ oscillations at the CERN SPS Wide-Band neutrino Beam. This search is performed via the appearance of ν τ in a predominantly ν μ beam of 24 GeV average energy. The experiment has been designed to allow a kinematical selection of ν τ charged current interactions from the background of ν μ and ν e charged and neutral current interactions and has maximum sensitivity in sin 2 2 θ for Δm 2 greater than 40 eV 2 , and some sensitivity remains for Δm 2 down to 1 eV 2 in the case of full mixing. NOMAD has taken data with the full detector since August 1995, and will pursue the oscillations search until the end of 1997. Charged and neutral current interactions of ν μ , ν¯ μ , ν e and V¯ e have been identified and comparisons between data and Monte-Carlo are presented. The status of the ν μ → ν τ oscillation search using various tau decay channels ( τ → μ , τ → e, τ → hadrons) is also reported.