EUROPEAN ORGANISATION FOR NUCLEAR RESEARCH

We have searched for excited states of charged and neutral leptons, e , , and , in ee collisions at p s = 161 GeV using the OPAL detector at LEP. No evidence for their existence was found. With the most common coupling assumptions, the topologies from excited lepton pair production include `` and `` WW , with the subsequent decay of the virtual W bosons. From the analysis of these topologies, 95% con dence level lower mass limits of 79:9 GeV for e , 80:0 GeV for , 79:1 GeV for , 78:3 GeV for e , 78:9 GeV for and 76:2 GeV for are inferred. From the analysis of W W and topologies with missing energy and using alternative coupling assignments which favour charged ` and photonic decays, 95% con dence level lower mass limits of 77.1 GeV for each ` avour and 77.8 GeV for each avour are inferred. From the analysis of the `` , ` W and single nal states expected from excited lepton single production, upper limits on the ratio of the coupling to the compositeness scale, f= , are determined for excited lepton masses up to the kinematic limit. Submitted to Physics Letters B The OPAL Collaboration K.Ackersta , G.Alexander, J.Allison, N.Altekamp, K.Ametewee, K.J.Anderson, S.Anderson, S.Arcelli, S.Asai, D.Axen, G.Azuelos, A.H.Ball, E.Barberio, R.J. Barlow, R.Bartoldus, J.R.Batley, J. Bechtluft, C.Beeston, T.Behnke, A.N.Bell, K.W.Bell, G.Bella, S. Bentvelsen, P.Berlich, S. Bethke, O.Biebel, V.Blobel, I.J. Bloodworth, J.E.Bloomer, M.Bobinski, P.Bock, H.M.Bosch, M.Boutemeur, B.T.Bouwens, S. Braibant, R.M.Brown, H.J. Burckhart, C.Burgard, R.B urgin, P.Capiluppi, R.K.Carnegie, A.A.Carter, J.R.Carter, C.Y.Chang, D.G.Charlton, D.Chrisman, P.E.L.Clarke, I. Cohen, J.E.Conboy, O.C.Cooke, M.Cu ani, S.Dado, C.Dallapiccola, G.M.Dallavalle, S.De Jong, L.A. del Pozo, K.Desch, M.S.Dixit, E. do Couto e Silva, M.Doucet, E.Duchovni, G.Duckeck, I.P.Duerdoth, J.E.G.Edwards, P.G.Estabrooks, H.G.Evans, M.Evans, F. Fabbri, P. Fath, F. Fiedler, M.Fierro, H.M.Fischer, R. Folman, D.G.Fong, M.Foucher, A. F urtjes, P.Gagnon, J.W.Gary, J.Gascon, S.M.Gascon-Shotkin, N.I.Geddes, C.Geich-Gimbel, T.Geralis, G.Giacomelli, P.Giacomelli, R.Giacomelli, V.Gibson, W.R.Gibson, D.M.Gingrich, D.Glenzinski, J.Goldberg, M.J.Goodrick, W.Gorn, C.Grandi, E.Gross, J.Grunhaus M.Gruw e, C.Hajdu, G.G.Hanson, M.Hansroul, M.Hapke, C.K.Hargrove, P.A.Hart, C.Hartmann, M.Hauschild, C.M.Hawkes, R.Hawkings, R.J.Hemingway, M.Herndon, G.Herten, R.D.Heuer, M.D.Hildreth, J.C.Hill, S.J.Hillier, T.Hilse, P.R.Hobson, R.J.Homer, A.K.Honma, D.Horv ath, R.Howard, R.E.Hughes-Jones, D.E.Hutchcroft, P. Igo-Kemenes, D.C. Imrie, M.R. Ingram, K. Ishii, A. Jawahery, P.W. Je reys, H. Jeremie, M. Jimack, A. Joly, C.R. Jones, G. Jones, M. Jones, R.W.L. Jones, U. Jost, P. Jovanovic, T.R. Junk, D.Karlen, K.Kawagoe, T.Kawamoto, R.K.Keeler, R.G.Kellogg, B.W.Kennedy, B.J.King, J.Kirk, S.Kluth, T.Kobayashi, M.Kobel, D.S.Koetke, T.P.Kokott, M.Kolrep, S.Komamiya, T.Kress, P.Krieger, J. von Krogh, P.Kyberd, G.D. La erty, R. Lahmann, W.P. Lai, D. Lanske, J. Lauber, S.R. Lautenschlager, J.G. Layter, D. Lazic, A.M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, C. Lewis, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, M.Mannelli, S.Marcellini, C.Markus, A.J.Martin, J.P.Martin, G.Martinez, T.Mashimo, W.Matthews, P.Mattig, W.J.McDonald, J.McKenna, E.A.Mckigney, T.J.McMahon, A.I.McNab, R.A.McPherson, F.Meijers, S.Menke, F.S.Merritt, H.Mes, J.Meyer, A.Michelini, G.Mikenberg, D.J.Miller, R.Mir, W.Mohr, A.Montanari, T.Mori, M.Morii, U.M uller, K.Nagai, I. Nakamura, H.A.Neal, B.Nellen, B.Nijjhar, R.Nisius, S.W.O'Neale, F.G.Oakham, F.Odorici, H.O.Ogren, N.J.Oldershaw, T.Omori, M.J.Oreglia, S.Orito, J. P alink as, G. P asztor, J.R. Pater, G.N.Patrick, J. Patt, M.J. Pearce, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Po enberger, B. Poli, A. Posthaus, H. Przysiezniak, D.L.Rees, D.Rigby, S. Robertson, S.A.Robins, N.Rodning, J.M.Roney, A.Rooke, E.Ros, A.M.Rossi, M.Rosvick, P.Routenburg, Y.Rozen, K.Runge, O.Runolfsson, U.Ruppel, D.R.Rust, R.Rylko, K. Sachs, E.K.G. Sarkisyan, M. Sasaki, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Schar -Hansen, P. Schenk, B. Schmitt, S. Schmitt, M. Schroder, H.C. Schultz-Coulon, M. Schulz, M. Schumacher, P. Sch utz, W.G. Scott, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler,