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Precise Determination of the Z Resonance Parameters at LEP: Zedometry

This final analysis of hadronic and leptonic cross-sections and of leptonic forward-backward asymmetries in e+e- collisions with the OPAL detector makes use of the full LEP1 data sample comprising 161 pb^-1 of integrated luminosity and 4.5 x 10^6 selected Z decays. An interpretation of the data in t...

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Detalles Bibliográficos
Autores principales: Abbiendi, G., Ainsley, C., Akesson, P.F., Alexander, G., Allison, John, Anagnostou, G., Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Benelli, G., Bentvelsen, S., Beeston, C., Bethke, S., Biebel, O., Bloodworth, I.J., Boeriu, O., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Cammin, J., Capiluppi, P., Carnegie, R.K., Caron, B., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Coxe, R.L., Csilling, A., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Darling, C., De Roeck, A., De Wolf, E.A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanti, M., Feld, L., Ferrari, P., Fiedler, F., Fleck, I., Ford, M., Foucher, M., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gascon, J., Gascon-Shotkin, S.M., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Giacomelli, R., Glenzinski, D., Goldberg, J., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Gunther, P.O., Hajdu, C., Hanson, G.G., Harder, K., Harel, A., Harin-Dirac, M., Hart, P.A., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Hensel, C., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Kirk, J., Klein, K., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Kokott, T.P., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Krop, D., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Landsman, H., Lanske, D., Lauber, J., Lawson, I, Layter, J.G., Lee, A.M., Leins, A., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Menges, W., Menke, S., Merritt, F.S., Mes, H., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Muller, U., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Oh, A., Okpara, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palmonari, F., Pasztor, G., Pater, J.R., Patrick, G.N., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Pooth, O., Przybycien, M., Quadt, A., Quast, G., Rabbertz, K., Raith, B., Rembser, C., Renkel, P., Rick, H., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schmitt, B., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Smith, T.J., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Springer, Robert Wayne, Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Stumpf, L., Surrow, B., Talbot, S.D., Tarem, S., Taylor, R.J., Teuscher, R., Tecchio, M., Thomas, J., Thomson, M.A., Towers, S., Toya, D., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsukamoto, T., Tsur, E., Turner-Watson, M.F., Ueda, I., Vachon, B., Vannerem, P., Verzocchi, M., Vokurka, E.H., Voss, H., Vossebeld, J., Wagner, A., Wagner, D.L., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., Zer-Zion, D.
Lenguaje:eng
Publicado: 2000
Materias:
Acceso en línea:https://dx.doi.org/10.1007/s100520100627
http://cds.cern.ch/record/479562
Descripción
Sumario:This final analysis of hadronic and leptonic cross-sections and of leptonic forward-backward asymmetries in e+e- collisions with the OPAL detector makes use of the full LEP1 data sample comprising 161 pb^-1 of integrated luminosity and 4.5 x 10^6 selected Z decays. An interpretation of the data in terms of contributions from pure Z exchange and from Z-gamma interference allows the parameters of the Z resonance to be determined in a model-independent way. Our results are in good agreement with lepton universality and consistent with the vector and axial-vector couplings predicted in the Standard Model. A fit to the complete dataset yields the fundamental Z resonance parameters: mZ = 91.1852 +- 0.0030 GeV, GZ = 2.4948 +- 0.0041 GeV, s0h = 41.501 +- 0.055 nb, Rl = 20.823 +- 0.044, and Afb0l = 0.0145 +- 0.0017. Transforming these parameters gives a measurement of the ratio between the decay width into invisible particles and the width to a single species of charged lepton, Ginv/Gl = 5.942 +- 0.027. Attributing the entire invisible width to neutrino decays and assuming the Standard Model couplings for neutrinos, this translates into a measurement of the effective number of light neutrino species, N_nu = 2.984 +- 0.013. Interpreting the data within the context of the Standard Model allows the mass of the top quark, mt = 162 +29-16 GeV, to be determined through its influence on radiative corrections. Alternatively, utilising the direct external measurement of mt as an additional constraint leads to a measurement of the strong coupling constant and the mass of the Higgs boson: alfa_s(mZ) = 0.127 +- 0.005 and mH = 390 +750-280 GeV.