Study of a new experiment for the search of $\nu_{\mu}-\nu_{\tau}$ oscillations

We present the conceptual design of TENOR (Tracking and Emulsions for Neutrino Oscillation Research), a ``short-baseline'' experiment aiming at a new high sensitivity search for $\nu_{\mu}-\nu_{\tau}$ oscillations in the CERN Wide Band Neutrino Beam. We show that by exploiting the advances in the technology of nuclear emulsions, one can conceive a hybrid apparatus with an emulsion target a factor six heavier than the one presently used in the CHORUS experiment. The main features of the experiment are discussed, as well as the issues of data selection, background reduction, and sensitivity in the determination of $sin^22\theta_{\mu\tau}$. The present estimates on the experimental backgrounds are extrapolated from those anticipated for the CHORUS experiment; a more thorough study is still needed. The expected sensitivity of the experiment on the oscillation mixing angle is more than a factor 15 higher than those of the present explorations. In the case of a negative search, and for large $\Delta m^2$, the 90\% CL upper limit in the mixing angle would be $sin^22\theta_{\mu\tau} < 9~\times~10^{-6}$.