Direct observation of longitudinally polarised W +/- bosons

Authors
Acciarri, M Achard, P Adriani, O Aguilar-Benitez, M Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Balandras, A Ball, RC Banerjee, S Banerjee, S Barczyk, A Barillere, R Barone, L Bartalini, P Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Bellucci, L Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Blaising, JJ Blyth, SC Bobbink, GJ Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brochu, F Buffini, A Buijs, A Burger, JD Burger, WJ Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, H Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chiefari, G Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F Cozzoni, B de la Cruz, B Csilling, A Cucciarelli, S Dai, TS van Dalen, JA D'Alessandro, R de Asmundis, R Deglon, P Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F De Salvo, A Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Dufournaud, D Duinker, P Duran, I El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Gong, ZF Grenier, G Grimm, O Gruenewald, MW Guida, M van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hasan, A Hatzifotiadou, D Hebbecker, T Herve, A Hidas, P Hirschfelder, J Hofer, H Holzner, G Hoorani, H Hou, SR Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Khan, RA Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kim, SC Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Koutsenko, V Kraber, M Kraemer, RW Krenz, W Kruger, A Kunin, A de Guevara, PL Laktineh, I Landi, G Lassila-Perini, K Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Likhoded, S Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, YS Lubelsmeyer, K Luci, C Luckey, D Lugnier, L Luminari, L Lustermann, W Ma, WG Maity, M Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Mihul, A Milcent, H Mirabelli, G Mnich, J Mohanty, GB Molnar, P Monteleoni, B Moulik, T Muanza, GS Muheim, F Muijs, AJM Musy, M Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, T Nisati, A Nowak, H Oh, YD Organtini, G Oulianov, A Palomares, C Pandoulas, D Paoletti, S Paolucci, P Paramatti, R Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Pedace, M Pensotti, S Perret-Gallix, D Petersen, B Piccolo, D Pierella, F Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, DO Prokofiev, D Quartieri, J Rahal-Callot, G Rahaman, MA Raics, P Raja, N Ramelli, R Rancoita, PG Raspereza, A Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Rodin, J Roe, BP Romero, L Rosca, A Rosier-Lees, S Rubio, JA Ruschmeier, D Rykaczewski, H Saremi, S Sarkar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Schopper, H Schotanus, DJ Schwering, G Sciacca, C Sciarrino, D Seganti, A Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Stickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Suter, H Swain, JD Szillasi, Z Sztaricskai, T Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Vicinanza, D Viertel, G Villa, S Vivargent, M Vlachos, S Vodopianov, I Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, M Wang, XL Wang, ZM Weber, A Weber, M Wienemann, P Wilkens, H Wu, SX Wynhoff, S Xie, L Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC Zalite, A Zalite, Y Zhang, ZP Zhu, GY Zhu, RY Zichichi, A Zilizi, G Zoller, M
Citation
M. Acciarri et al., Direct observation of longitudinally polarised W +/- bosons, PHYS LETT B, 474(1-2), 2000, pp. 194-204
Citations number
28
Categorie Soggetti
Physics
Journal title
PHYSICS LETTERS B
ISSN journal
03702693 → ACNP
Volume
474
Issue
1-2
Year of publication
2000
Pages
194 - 204
Database
ISI
SICI code
0370-2693(20000210)474:1-2<194:DOOLPW>2.0.ZU;2-A
Abstract
The three different helicity states of W+/- bosons, produced in the reactio n e(+)e(-) --> W+W- --> lvq (q) over bar are studied using leptonic and had ronic W decays at root s = 183 GeV and 189 GeV. The W polarisation is also measured as a function of the scattering angle between the W- and the direc tion of the e(-) beam. The analysis demonstrates that W bosons are produced with all three helicities, the longitudinal and the two transverse states. Combining the results from the two center-of-mass energies and with lepton ic and hadronic W decays, the fraction of longitudinally polarised W+/- bos ons is measured to be 0.261 +/- 0.016(syst.) +/- 0.016(syst.) in agreement with the expectation from the Standard Model. (C) 2000 Elsevier Science B.V . All rights reserved.