@article{3075439,
    title = "A study of radiative muon-pair events at Z0 energies and limits on an additional Z′ gauge beson",
    author = "Abreu, P. and Adam, W. and Adye, T. and Agasi, E. and Ajinenko, I. and Aleksan, R. and Alekseev, G.D. and Allport, P.P. and Almehed, S. and Almeida, F.M.L. and Alvsvaag, S.J. and Amaldi, U. and Andreazza, A. and Antilogus, P. and Apel, W.-D. and Apsimon, R.J. and Arnoud, Y. and Asman, B. and Augustin, J.-E. and Augustinus, A. and Baillon, P. and Bambade, P. and Barao, F. and Barate, R. and Bardin, D.Y. and Barker, G.J. and Baroncelli, A. and Barring, O. and Barrio, J.A. and Bartl, W. and Bates, M.J. and Battaglia, M. and Baubillier, M. and Baudot, J. and Becks, K.-H. and Begalli, M. and Beilliere, P. and Beltran, P. and Benvenuti, A.C. and Berggren, M. and Bertrand, D. and Bianchi, F. and Bigi, M. and Bilenky, M.S. and Billoir, P. and Bjarne, J. and Bloch, D. and Blocki, J. and Blyth, S. and Bocci, V. and Bogolubov, P.N. and Bolognese, T. and Bonesini, M. and Bonivento, W. and Booth, P.S.L. and Borisov, G. and Bosio, C. and Bostjancic, B. and Bosworth, S. and Botner, O. and Boudinov, E. and Bouquet, B. and Bourdarios, C. and Bowcock, T.J.V. and Bozzo, M. and Braibant, S. and Branchini, P. and Brand, K.D. and Brenner, R.A. and Briand, H. and Bricman, C. and Brillault, L. and Brown, R.C.A. and Brunet, J.-M. and Bugge, L. and Buran, T. and Buys, A. and Buytaert, J.A.M.A. and Caccia, M. and Calvi, M. and Camacho Rozas, A.J. and Campion, R. and Camporesi, T. and Capale, V. and Cankocak, K. and Cao, F. and Carena, F. and Carrilho, P. and Carroll, L. and Cases, R. and Caso, C. and Castillo Gimenez, M.V. and Cattai, A. and Cavallo, F.R. and Cerrito, L. and Chabaud, V. and Chan, A. and Chapkin, M. and Charpentier, Ph. and Chaussard, L. and Chauveau, J. and Checchia, P. and Chelkov, G.A. and Chliapnikov, P. and Chorowicz, V. and Chrin, J.T.M. and Cindro, V. and Collins, P. and Contreras, J.L. and Contri, R. and Cortina, E. and Cosme, G. and Cosmo, G. and Cossutti, C. and Couchot, F. and Crawley, H.B. and Crennell, D. and Crosetti, G. and Cuevas Maestro, J. and Czellar, S. and Dahl-Jensen, E. and Dahm, J. and Dalmagne, B. and Dam, M. and Damgaard, G. and Daubie, E. and Daum, A. and Dauncey, P.D. and Davenport, M. and Davies, J. and Da Silva, W. and Defoix, C. and Delpierre, P. and Demaria, N. and De Angelis, A. and De Boeck, H. and De Boer, W. and De Brabandere, S. and De Clercq, C. and De Fez Laso, M.D.M. and De La Vaissiere, C. and De Lotto, B. and De Min, A. and De Paula, L. and De Saint-Jean, C. and Diikstra, H. and Di Ciaccio, L. and Diama, F. and Dolbeau, J. and Donszelmann, M. and Doroba, K. and Dracos, M. and Drees, J. and Dris, M. and Dufour, Y. and Dupont, F. and Edsall, D. and Ehret, R. and Ekelof, T. and Ekspong, G. and Elsing, M. and Engel, J.-P. and Ershaidat, N. and Espirito Santo, M. and Fassouliotis, D. and Feindt, M. and Fenyuk, A. and Ferrer, A. and Filippas, T.A. and Firestone, A. and Foeth, H. and Fokitis, E. and Fontanelli, F. and Formenti, F. and Fousset, J.-L. and Franek, B. and Frenkiel, P. and Fries, D.C. and Frodesen, A.G. and Fruhwirth, R. and Fulda-Quenzer, F. and Furstenau, H. and Fuster, J. and Gamba, D. and Gandelman, M. and Garcia, C. and Garcia, J. and Gaspar, C. and Gasparini, U. and Gavillet, Ph. and Gazis, E.N. and Gele, D. and Gerber, J.-P. and Giacomelli, P. and Gillespie, D. and Gokieli, R. and Golob, B. and Golovatyuk, V.M. and Gomez Y Cadenas, J.J. and Gopal, G. and Gorn, L. and Gorski, M. and Gracco, V. and Grard, F. and Graziani, E. and Grosdidier, G. and Gunnarsson, P. and Guy, J. and Haedinger, U. and Hahn, F. and Hahn, M. and Hahn, S. and Haider, S. and Hajduk, Z. and Hakansson, A. and Hallgren, A. and Hamacher, K. and Hao, W. and Harris, F.J. and Hedberg, V. and Henriques, R. and Hernandez, J.J. and Hernando, J.A. and Herquet, P. and Herr, H. and Hessing, T.L. and Higon, E. and Hilke, H.J. and Hill, T.S. and Holmgren, S.-O. and Holt, P.J. and Holthuizen, D. and Honore, P.F. and Houlden, M. and Hrubec, J. and Huet, K. and Hultqvist, K. and Ioannou, P. and Iversen, P.-S. and Jackson, J.N. and Jacobsson, R. and Jalocha, P. and Jarlskog, G. and Jarry, P. and Jean-Marie, B. and Johansson, E.K. and Jonker, M. and Jonsson, L. and Juillot, P. and Kaiser, M. and Kalmus, G. and Kapusta, F. and Karlsson, M. and Karvelas, E. and Katsanevas, S. and Katsoufis, E.C. and Keranen, R. and Khomenko, B.A. and Khovanski, N.N. and King, B. and Kjaer, N.J. and Klein, H. and Klovning, A. and Kluit, P. and Koch-Mehrin, A. and Koehne, J.H. and Koene, B. and Kokkinias, P. and Koratzinos, M. and Korcyl, K. and Korytov, A.V. and Kostioukhine, V. and Kourkoumelis, C. and Kouznetsov, O. and Kramer, P.H. and Krammer, M. and Kreuter, C. and Krolikowski, J. and Kronkvist, I. and Krupinski, W. and Kulka, K. and Kurvinen, K. and Lacasta, C. and Laktineh, I. and Lambropoulos, C. and Lamsa, J.W. and Lanceri, L. and Langefeld, P. and Lapin, V. and Last, I. and Laugier, J.-P. and Lauhakangas, R. and Leder, G. and Ledroit, F. and Leitner, R. and Lemoigne, Y. and Lemonne, J. and Lenzen, G. and Lepeltier, V. and Lesiak, T. and Levy, J.M. and Lieb, E. and Liko, D. and Lindner, R. and Lipniacka, A. and Lippi, I. and Loerstad, B. and Lokajicek, M. and Loken, J.G. and Lopez-Fernandez, A. and Lopez Aguera, M.A. and Los, M. and Loukas, D. and Lozano, J.J. and Lutz, P. and Lyons, L. and Maehlum, G. and Maillard, J. and Maio, A. and Maltezos, A. and Mandl, F. and Marco, J. and Marechal, B. and Margoni, M. and Marin, J.-C. and Mariotti, C. and Markou, A. and Maron, T. and Marti, S. and Martinez-Rivero, C. and Martinez-Vidal, F. and Matorras, F. and Matteuzzi, C. and Matthiae, G. and Mazzucato, M. and Cubbin, M.M. and Kay, R.M. and Nulty, R.M. and Medbo, J. and Meroni, C. and Meyer, W.T. and Michelotto, M. and Migliore, E. and Mikulec, I. and Mirabito, L. and Mitaroff, W.A. and Mitselmakher, G.V. and Mjoernmark, U. and Moa, T. and Moeller, R. and Moenig, K. and Monge, M.R. and Morettini, P. and Mueller, H. and Murray, W.J. and Muryn, B. and Myatt, G. and Naraghi, F. and Navarria, F.L. and Negri, P. and Nemecek, S. and Neumann, R. and Nicolaidou, R. and Nielsen, B.S. and Niss, P. and Nomerotski, A. and Normand, A. and Obraztsov, V. and Olshevski, A.G. and Orava, R. and Osterberg, K. and Ouraou, A. and Paganini, P. and Paganoni, M. and Pain, R. and Palka, H. and Papadopoulou, Th.D. and Pape, L. and Parodi, F. and Passeri, A. and Pegararo, M. and Pennanen, J. and Peralta, L. and Pernegger, H. and Pernicka, M. and Perrotta, A. and Petridou, C. and Petrolini, A. and Phillips, H.T. and Piana, G. and Pierre, F. and Pimenta, M. and Plaszczynski, S. and Podobrin, O. and Pol, M.E. and Polok, G. and Poropat, P. and Pozdniakov, V. and Prest, M. and Privitera, P. and Pullia, A. and Radojicic, D. and Ragazzi, S. and Rahmani, H. and Rames, J. and Ratoff, P.N. and Read, A.L. and Reale, M. and Rebecchi, P. and Redaelli, N.G. and Regler, M. and Reid, D. and Renton, P.B. and Resvanis, L.K. and Richard, F. and Richardson, J. and Ridky, J. and Rinaudo, G. and Ripp, I. and Romero, A. and Roncagliolo, I. and Ronchese, P. and Roos, L. and Rosenberg, E.I. and Rosso, E. and Roudeau, P. and Rovelli, T. and Ruckstuhl, W. and Ruhlmann-Kleider, V. and Ruiz, A. and Rybicki, K. and Saarikko, H. and Sacquin, Y. and Sajot, G. and Salt, J. and Sanchez, J. and Sannino, M. and Schael, S. and Schneider, H. and Schyns, M.A.E. and Sciolla, G. and Scuri, F. and Segar, A.M. and Seitz, A. and Sekulin, R. and Seufert, R. and Shellard, R.C. and Siccama, I. and Siegrist, P. and Simonetti, S. and Simonetto, F. and Sisakian, A.N. and Skaali, T.B. and Smadja, G. and Smirnov, N. and Smirnova, O. and Smith, G.R. and Sosnowski, R. and Souza-Santos, D. and Spassov, T. and Spiriti, E. and Squarcia, S. and Staeck, H. and Stanescu, C. and Stapnes, S. and Stavitski, I. and Stavropoulos, G. and Stepaniak, K. and Stichelbaut, F. and Stocchi, A. and Strauss, J. and Straver, J. and Strub, R. and Stugu, B. and Szczekowski, M. and Szeptycka, M. and Tabarelli, T. and Tchikilev, O. and Theodosiou, G.E. and Thome, Z. and Tilquin, A. and Timmermans, J. and Timofeev, V.G. and Tkatchev, L.G. and Todorov, T. and Toet, D.Z. and Tomaradze, A. and Tome, B. and Torassa, E. and Tortora, L. and Transtromer, G. and Treille, D. and Trischuk, W. and Tristram, G. and Troncon, C. and Tsirou, A. and Tsyganov, E.N. and Turala, M. and Turluer, M.-L. and Tuuva, T. and Tyapkin, I.A. and Tyndel, M. and Tzamarias, S. and Ueberschaer, B. and Ueberschaer, S. and Ullaland, O. and Uvarov, V. and Valenti, G. and Vallazza, E. and Valls Ferrer, J.A. and Vander Velde, C. and Van Apeldoorn, G.W. and Van Dam, P. and Van Der Heijden, M. and Van Doninck, W.K. and Van Eldik, J. and Vaz, P. and Vegni, G. and Ventura, L. and Venus, W. and Verbeure, F. and Verlato, M. and Vertogradov, L.S. and Vilanova, D. and Vincent, P. and Vitale, L. and Vlasov, E. and Vodopyanov, A.S. and Vollmer, M. and Voutilainen, M. and Wahlen, H. and Walck, C. and Wehr, A. and Weierstall, M. and Weilhammer, P. and Wetherell, A.M. and Wickens, J.H. and Wielers, M. and Wilkinson, G.R. and Williams, W.S.C. and Winter, M. and Witek, M. and Wormser, G. and Woschnagg, K. and Yip, K. and Yushchenko, O. and Zach, F. and Zaitsev, A. and Zalewska, A. and Zalewski, P. and Zavrtanik, D. and Zevgolatakos, E. and Zimin, N.I. and Zito, M. and Zontar, D. and Zuberi, R. and Zumerle, G.",
    journal = "ZEITSCHRIFT FUR PHYSIK. SECTION C, PARTICLES AND FIELDS",
    year = "1995",
    volume = "65",
    number = "4",
    pages = "603-618",
    issn = "0170-9739",
    doi = "10.1007/BF01578669",
    abstract = "An analysis is reported on the channel e+e-→μ+μ- (nγ), n=1,2..., using data taken with the DELPHI detector at LEP from 1990 to 1992. Differential cross sections of the radiative photons as a function of photon energy and of the angle between the photon and the muon are presented. No significant deviations from expectations are observed. The data are also used to extract the muon-pair cross section and asymmetry below the Z0 peak by using those events with relatively hard initial state radiative photon(s). The measured cross section and asymmetry show no significant deviation from the Standard Model expectations. These results together with the DELPHI cross section and asymmetry measurements at the LEP energies from the 1990 to 1992 running periods are used to determine limits on the Z0-Z′ gauge boson mixing angle θZ′ and on the Z′ mass. There is no indication of the existence of a Z′; the limits obtained on the mixing angle substantially improve upon existing limits. The 95% confidence level allowed ranges of θZ′ in various models are: {Mathematical expression} © 1995 Springer-Verlag."
}