https://doi.org/10.1140/epjc/s2006-02576-8
Experimental Physics
Measurement of the W boson mass and width in e+e- collisions at LEP
1
Physikalisches Institut, RWTH-Aachen, 52056, Aachen, Germany
2
Laboratoire de Physique des Particules (LAPP), IN2P3-CNRS, 74019, Annecy-le-Vieux Cedex, France
3
Institut de Física d’Altes Energies, Universitat Autònoma de Barcelona, 08193, Bellaterra (Barcelona), Spain
4
Dipartimento di Fisica, INFN Sezione di Bari, 70126, Bari, Italy
5
Institute of High Energy Physics, Academia Sinica, Beijing, P.R. China
6
European Laboratory for Particle Physics (CERN), 1211, Geneva 23, Switzerland
7
Laboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, 63177, Aubière, France
8
Niels Bohr Institute, 2100, Copenhagen, Denmark
9
Nuclear Research Center Demokritos (NRCD), 15310, Attiki, Greece
10
Laoratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, 91128, Palaiseau Cedex, France
11
Dipartimento di Fisica, Università di Firenze, INFN Sezione di Firenze, 50125, Firenze, Italy
12
Department of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
13
Utah Valley State College, Orem, UT, 84058, USA
14
Laboratori Nazionali dell’INFN (LNF-INFN), 00044, Frascati, Italy
15
Kirchhoff-Institut für Physik, Universität Heidelberg, 69120, Heidelberg, Germany
16
Department of Physics, Imperial College, London, SW7 2BZ, UK
17
Institut für Experimentalphysik, Universität Innsbruck, 6020, Innsbruck, Austria
18
Department of Physics, University of Lancaster, Lancaster, LA1 4YB, UK
19
Institut de Physique Nucléaire, Département de Physique, Université Catholique de Louvain, 1348, Louvain-la-Neuve, Belgium
20
Institut für Physik, Universität Mainz, 55099, Mainz, Germany
21
Centre de Physique des Particules de Marseille, Univ. Méditerranée, IN2P3-CNRS, 13288, Marseille, France
22
Dipartimento di Fisica, Università di Milano e INFN Sezione di Milano, 20133, Milano, Italy
23
Werner-Heisenberg-Institut, Max-Planck-Institut für Physik, 80805, München, Germany
24
Laboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, IN2P3-CNRS, 91898, Orsay Cedex, France
25
Dipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 56010, Pisa, Italy
26
Department of Physics, Royal Holloway & Bedford New College, University of London, Egham, Surrey, TW20 OEX, UK
27
Particle Physics Dept., Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 OQX, UK
28
CEA, DAPNIA/Service de Physique des Particules, CE-Saclay, 91191, Gif-sur-Yvette Cedex, France
29
Institute for Particle Physics, University of California at Santa Cruz, Santa Cruz, CA, 95064, USA
30
Department of Physics, University of Sheffield, Sheffield, S3 7RH, UK
31
Fachbereich Physik, Universität Siegen, 57068, Siegen, Germany
32
Dipartimento di Fisica, Università di Trieste e INFN Sezione di Trieste, 34127, Trieste, Italy
33
Experimental Elementary Particle Physics, University of Washington, Seattle, WA, 98195, USA
34
Department of Physics, University of Wisconsin, Madison, WI, 53706, USA
35
Institute for Particle Physics, ETH Hönggerberg, 8093, Zürich, Switzerland
Received:
4
March
2006
Revised:
25
April
2006
Published online:
7
June
2006
The mass of the W boson is determined from the direct reconstruction of W decays in WW→qq̄qq̄ and WW→ℓνqq̄ events in e+e- collisions at LEP. The data sample corresponds to an integrated luminosity of 683 pb-1 collected with the ALEPH detector at centre-of-mass energies up to 209 GeV. To minimise any effect from colour reconnection a new procedure is adopted in which low energy particles are not considered in the mass determination from the qq̄qq̄ channel. The combined result from all channels is where FSI represents the possible effects of final state interactions in the qq̄qq̄ channel and LEP indicates the uncertainty in the beam energy. From two-parameter fits to the W mass and width, the W width is found to be
© Springer-Verlag, 2006