PHYSICS LETTERS B, cilt.434, ss.205-213, 1998 (SCI-Expanded)
Part of the neutrino events collected in 1994-1995 by the CHORUS experiment has been analysed. A search was performed for nu(tau) charged current interactions followed by the tau lepton decay into a single charged negative hadron, a possible indication for nu(mu) --> nu(tau) oscillation. A sample of 6844 events without an identified muon has been located in the emulsion target. Within the selection criteria, no tau(-) candidate has been found. Combining this result with the one from the search fur nu(tau) interactions using the muonic decay mode (36182 events with an identified muon), a 90% C.L. limit on the mixing angle sin(2)2 theta(mu tau) < 1.8.10(-3) (at large Delta m(2)) has been derived. (C) 1998 Published by Elsevier Science B.V. All rights reserved.