Search for heavy neutral and charged leptons in e + e annihilation at ZF = 161 and ¿ F = 172 GeV L 3 Collaboration
M. Acciarri,O. Adriani,M. Aguilar-Benitez,S. Ahlen,J. Alcaraz,G. Alemanni,J. Allaby,A. Aloisio,G. Alverson,M. G. Alviggi,G. Ambrosi,H. Anderhub,Ay,V. P. Andreev,T. Angelescu,F. Anselmo,A. Arefiev,T. Azemoon,T. Aziz,P. Bagnaia,L. Baksay,S. Banerjee,Sw. Banerjee,K. Banicz,A. Barczyk,R. Barillère,L. Barone,P.,Bartalini,A. Baschirotto,M. Basile,R. Battiston,A. Bay,F.,Becattini,U. Becker,F. Behner,J.,Berdugo,P. Berges,B. Bertucci,B. L. Betev,S.,Bhattacharya,M. Biasini,A. Biland,G. M. Bilei,J. J. Blaising,S. C. Blyth,G. J. Bobbink,R. Bock,A. Böhm,L. Boldizsar,B. Borgia,D. Bourilkov,M. Bourquin,S. Braccini,J. G. Branson,V. Brigljevic,A. Buffini,A. Buijs,J. D. Burger,W. J. Burger,J. Busenitz,M. Campanelli,G.,Cara Romeo,G. Carlino,A. M. Cartacei,J. Casaus,G. Castellini,F. Cavallari,C. Cecchi,M. Cerrada,F. Cesaroni,M. Chamizo,U. K. Chaturvedi l,S. V. Chekanov,A. Chen,G. Chen,G. M. Chen,H. F. Chen,H. S. Chen,X. Chereau,Chiefari,C. Y. Chien,L. Cifarelli,F. Cindolo,C. Civinini,I. Clare,R. Clare,O. H.,Cohn,Coignet,A. P. Colijn,N. Colino,V. Commichau,S. Costantini,F. Cotorobai,B. de la Cruz,A. Csilling,R. de Asmundis,A. Degré,K. Deiters,D. della Volpe,P. Denes,F. DeNotaristefani,D. DiBitonto,M. Diemoz,D. van Dierendonck,C. Dionisi,M. Dittmar,A.,Dominguez,M. T. Dova,D. Duchesneau,P. Duinker,Dutta,H. El Mamouni,A. Engler,F. J. Eppling,F. C. Emé,J. P. Emenwein,P. Extermann,M. Fabre
semanticscholar（2019）
引用0|浏览17
暂无评分
摘要
A search for unstable neutral and charged heavy leptons as well as for stable charged heavy leptons has been made at center-of-mass energies fi = 161 GeV and 6 = 172 GeV with the L3 detector at LEP. No evidence for their existence was found. We exclude unstable neutral leptons of Dirac (Majorana) type for masses below 78.0 (66.7), 78.0 (66.7) and 72.2 (58.2) GeV, if the heavy neutrino couples to the electron, muon or tau family, respectively. We exclude unstable charged heavy leptons for masses below 81.0 GeV for a wide mass range of the associated neutral heavy lepton. The production of stable charged heavy leptons with a mass less than 84.2 GeV is also excluded. If the unstable charged heavy lepton decays via mixing into a massless neutrino, we exclude masses below 78.7 GeV.
