Measurement of the Z resonance parameters at LEP

Barate, R Decamp, D Ghez, P Goy, C Lees, JP Lucotte, A Merle, E Minard, MN Pietrzyk, B Alemany, R Casado, MP Chmeissani, M Comas, P Crespo, JM Fernandez, E Fernandez-Bosman, M Garrido, L Grauges, E Juste, A Martinez, M Merino, G Miquel, R Mir, LM Orteu, S Pacheco, A Park, IC Perlas, J Riu, I Sanchez, F Colaleo, A Creanza, D de Palma, M Iaselli, G Maggi, G Maggi, M Nuzzo, S Ranieri, A Raso, G Ruggieri, F Selvaggi, G Silvestris, L Tempesta, P Tricomi, A Zito, G Huang, X Lin, J Ouyang, Q Wang, T Xie, Y Xu, R Xue, S Zhang, J Zhang, L Zhao, W Abbaneo, D Bazarko, A Becker, U Boix, G Bird, F Blucher, E Bonvicini, G Bright-Thomas, P Cattaneo, M Cerutti, F Ciulli, V Dissertori, G Drevermann, H Forty, RW Frank, M Greening, TC Hagelberg, R Halley, AW Hansen, JB Harvey, J Jacobsen, R Janot, P Jost, B Knobloch, J Lazeyras, P Lehraus, I Maley, P Mato, P May, J Moutoussi, A Ranjard, F Rolandi, L Schlatter, D Schmitt, M Schneider, O Spagnolo, P Tejessy, W Teubert, F Tomalin, IR Tournefier, E Veenhof, R Wiedenmann, W Wright, AE Ajaltouni, Z Badaud, F Chazelle, G Deschamps, O Falvard, A Ferdi, C Gay, P Guicheney, C Henrard, P Jousset, J Michel, B Monteil, S Montret, JC Pallin, D Perret, P Podlyski, F Bertelsen, H Fernley, T Hansen, F Hansen, JD Hansen, JR Hansen, PH Lindahl, A Mollerud, R Nilsson, BS Rensch, B Waananen, A Daskalakis, G Kyriakis, A Markou, C Simopoulou, E Siotis, I Vayaki, A Blondel, A Bonneaud, G Brient, JC Rouge, A Rumpf, M Swynghedauw, M Tanaka, R Verderi, M Videau, H Focardi, E Parrini, G Zachariadou, K Cavanaugh, R Corden, M Georgiopoulos, C Antonelli, A Bencivenni, G Bologna, G Bossi, F Campana, P Capon, G Chiarella, V Felici, G Laurelli, P Mannocchi, G Murtas, F Murtas, GP Passalacqua, L Pepe-Altarelli, M Picchi, P Colrain, P ten Have, I Hughes, IS Knowles, IG Lynch, JG Morton, WT Raine, C Reeves, P O'Shea, V Scarr, JM Smith, K Thompson, AS Turnbull, RM Buchmuller, O Dhamotharan, S Geweniger, C Hanke, P Hansper, G Hepp, V Kluge, EE Putzer, A Sommer, J Tittel, K Werner, S Wunsch, M Beuselinck, R Binnie, DM Cameron, W Dornan, PJ Girone, M Goodsir, S Martin, EB Marinelli, N Nash, J Sciaba, A Sedgbeer, JK Thomson, E Williams, MD Ghete, VM Girtler, P Kneringer, E Kuhn, D Rudolph, G Bowdery, CK Buck, PG Finch, AJ Foster, F Hughes, G Jones, RWL Keemer, NR Robertson, NA Sloan, T Snow, SW Williams, MI Bauerdick, LAT van Gemmeren, P Giehl, I Jakobs, K Kasemann, M Kleinknecht, K Quast, G Renk, B Rohne, E Sander, HG Schmelling, M Wachsmuth, H Wanke, R Zeitnitz, C Aubert, JJ Benchouk, C Bonissent, A Carr, J Coyle, P Etienne, F Motsch, F Payre, P Rousseau, D Talby, M Thulasidas, M Aleppo, M Antonelli, M Ragusa, F Buscher, V Dietl, H Ganis, G Huttmann, K Lutjens, G Mannert, C Manner, W Moser, HG Schael, S Settles, R Seywerd, H Stenzel, H Wiedenmann, W Wolf, G Azzurri, P Boucrot, J Callot, O Chen, S Cordier, A Davier, M Duflot, L Grivaz, JF Heusse, P Jacholkowska, A Le Diberder, F Lefrancois, J Lutz, AM Schune, MH Veillet, JJ Videau, I Zerwas, D Bagliesi, G Bettarini, S Boccali, T Bozzi, C Calderini, G Dell'Orso, R Fantechi, R Ferrante, I Fidecaro, F Foa, L Giassi, A Gregorio, A Ligabue, F Lusiani, A Marrocchesi, PS Messineo, A Palla, F Rizzo, G Sanguinetti, G Sguazzoni, G Steinberger, J Tenchini, R Vannini, C Venturi, A Verdini, PG Blair, GA Cowan, G Green, MG Medcalf, T Strong, JA von Wimmersperg-Toeller, JH Botterill, DR Clifft, RW Edgecock, TR Edwards, M Haywood, SJ Norton, PR Thompson, JC Bloch-Devaux, B Colas, P Emery, S Kozanecki, W Lancon, E Lemaire, MC Locci, E Perez, P Rander, J Renardy, JF Roussarie, A Schuller, JP Schwindling, J Vallage, B Black, SN Dann, JH Kim, HY Konstantinidis, N Litke, AM McNeil, MA Taylor, G Booth, CN Cartwright, S Combley, F Lehto, M Thompson, LF Affholderbach, K Barberio, E Bohrer, A Brandt, S Burkhardt, H Feigl, E Grupen, C Hess, J Lutters, G Meinhard, H Minguet-Rodriguez, J Mirabito, L Misiejuk, A Neugebauer, E Prange, G Rivera, F Saraiva, P Schafer, U Seywerd, H Sieler, U Smolik, L Stephan, F Trier, H Appollonio, M Bosisio, L Della Marina, R Giannini, G Gobbo, B Musolino, G Pitis, L Kim, H Rothberg, J Wasserbaech, S Armstrong, SR Bellantoni, L Cinabro, D Conway, JS Elmer, P Feng, Z Ferguson, DPS Gao, Y Gonzalez, S Grahl, J Harton, JL Hayes, OJ Hu, H Jin, S Johnson, RP Kile, J McNamara, PA Nielsen, J Orejudos, W Pan, YB Saadi, Y Scott, IJ Sharma, V Walsh, AM Walsh, J Wear, J Wu, SL Wu, X Yamartino, JM Zobernig, G

R. Barate et al., Measurement of the Z resonance parameters at LEP, EUR PHY J C, 14(1), 2000, pp. 1-50

85

INGLESE

Article

Physics

EUROPEAN PHYSICAL JOURNAL C

1434-6044 → ACNP

14

1

2000

1 - 50

ISI

1434-6044(200004)14:1<1:MOTZRP>2.0.ZU;2-K

The properties of the Z resonance are measured from the analysis of 4.5 mil lion Z decays into fermion pairs collected with the ALEPII detector at LEP. The data are consistent with lepton universality. The resonance parameters are measured to be M-Z = (91.1885 +/- 0.0031) GeV/c(2), Gamma(Z) = (2.4941 +/- 0.0043) GeV, sigma(had)(0) = (41.559 +/- 0.058) nb and, combining the three lepton flavours, R-l = 20.725 +/- 0.039. The corresponding number of light neutrino species is N-v = 2.983 +/- 0.013 and the strong coupling con stant is alpha(s)(M-Z) = 0.114 +/- 0.004 +/- 0.002(QCD) + 0.005 log(10) [M- H/150 GeV/c(2)]. The lepton pair forward-backward asymmetry is measured to be A(FB)(0,l) = 0.0173 +/- 0.0016 from which the effective weak mixing angl e is described: sin(2) theta(eff)(lept) = 0.23089 +/- 0.00089. The measurem ent of the leptonic width Gamma(ll) = 84.02 +/- 0.15 MeV leads to a determi nation of the effective rho parameter rho(eff)(lept) = 1.0064 +/- 0.0018. T he data support the Standard Model and favour a light Higgs.