The ratio $R_{\tau\mu}(\Upsilon(1S)) = \Gamma_{\Upsilon(1S)\to\tau^+\tau^-}/\Gamma_{\Upsilon(1S)\to\mu^+\mu^-}$ is measured using a sample of $(121.8\pm1.2)\times10^6$ $\Upsilon(3S)$ events recorded by the BABAR detector. This measurement is intended as a test of lepton universality and as a search for a possible light pseudoscalar Higgs boson. In the standard model (SM) this ratio is expected to be close to 1. Any significant deviations would violate lepton universality and could be introduced by the coupling to a light pseudoscalar Higgs boson. The analysis studies the decays $\Upsilon(3S)\to\Upsilon(1S)\pi^+\pi^-$, $\Upsilon(1S)\to l^+l^-$, where $l=\mu,\tau$. The result, $R_{\tau\mu}(\Upsilon(1S)) = 1.005 \pm 0.013(stat.) \pm 0.022(syst.)$, shows no deviation from the expected SM value, while improving the precision with respect to previous measurements.

Test of lepton universality in Upsilon(1S) decays at BaBar / P. del Amo Sanchez, J. P. Lees, V. Poireau, E. Prencipe, V. Tisserand, J. Garra Tico, E. Grauges, M. Martinelli, A. Palano, M. Pappagallo, G. Eigen, B. Stugu, L. Sun,M. Battaglia, D. N. Brown, B. Hooberman, L.T. Kerth, Y.G. Kolomensky, G. Lynch, I.L. Osipenkov, T. Tanabe, C.M. Hawkes, N. Soni, A.T. Watson, H. Koch, T. Schroeder, D.J. Asgeirsson, C. Hearty, T.S. Mattison, J.A. McKenna, A. Khan, A. Randle Conde, V.E. Blinov, A.R. Buzykaev, V.P. Druzhinin, V.B. Golubev, A.P. Onuchin, S.I. Serednyakov, Y.I. Skovpen, E.P. Solodov, K.Y. Todyshev, A.N. Yushkov, M. Bondioli, S. Curry, D. Kirkby, A.J. Lankford, M. Mandelkern, E.C. Martin, D.P. Stoker, H. Atmacan, J.W. Gary, F. Liu, O. Long, G.M. Vitug, Z. Yasin, V. Sharma, C. Campagnari, T.M. Hong, D. Kovalskyi, J.D. Richman, A.M. Eisner, C.A. Heusch, J. Kroseberg, W.S. Lockman, A.J. Martinez, T. Schalk, B. A. Schumm, A. Seiden, L.O. Winstrom, C.H. Cheng, D.A. Doll, B. Echenard, D.G. Hitlin, P. Ongmongkolkul, F.C. Porter, A.Y. Rakitin, R. Andreassen, M.S. Dubrovin, G. Mancinelli, B. T. Meadows, M.D. Sokoloff, P.C. Bloom, W.T. Ford, A. Gaz, J.F. Hirschauer, M. Nagel, U. Nauenberg, J.G. Smith, S.R. Wagner, R. Ayad, W.H. Toki, A. Hauke, H. Jasper, T.M. Karbach, J. Merkel, A. Petzold, B. Spaan, K.Wacker, M.J. Kobel, K.R. Schubert, R. Schwierz, D. Bernard, M. Verderi, P.J. Clark, S. Playfer, J.E. Watson, M. Andreotti, D. Bettoni, C. Bozzi, R. Calabrese, A. Cecchi, G. Cibinetto, E. Fioravanti, P. Franchini, E. Luppi, M. Munerato, M. Negrini, A. Petrella, L. Piemontese, R. Baldini Ferroli, A. Calcaterra, R. de Sangro, G. Finocchiaro, M. Nicolaci, S. Pacetti, P. Patteri, I.M. Peruzzi, M. Piccolo, M. Rama, A. Zallo, R. Contri, E. Guido, M. Lo Vetere, M.R. Monge, S. Passaggio, C. Patrignani, E. Robutti, S. Tosi, B. Bhuyan, M. Morii, A. Adametz, J. Marks, S. Schenk, U. Uwer, F.U. Bernlochner, H.M. Lacker, T. Lueck, A. Volk, P.D. Dauncey, M. Tibbetts, P.K. Behera, U. Mallik, C. Chen, J. Cochran, H.B. Crawley, L. Dong, W.T. Meyer, S. Prell, E.I. Rosenberg, A.E. Rubin, Y.Y. Gao, A.V. Gritsan, Z.J. Guo, N. Arnaud, M. Davier, D. Derkach, J. Firmino da Costa, G. Grosdidier, F. Le Diberder, A.M. Lutz, B. Malaescu, A. Perez, P. Roudeau, M.H. Schune, J. Serrano, V. Sordini, A. Stocchi,L. Wang, G. Wormser, D.J. Lange, D.M. Wright, I. Bingham, J.P. Burke, C.A. Chavez, J.P. Coleman, J.R. Fry, E. Gabathuler, R. Gamet, D.E. Hutchcroft, D.J. Payne, C. Touramanis, A.J. Bevan, F. Di Lodovico, R. Sacco, M. Sigamani, G. Cowan, S. Paramesvaran, A.C. Wren, D.N. Brown, C.L. Davis, A.G. Denig, M. Fritsch, W. Gradl, A. Hafner, K.E. Alwyn, D. Bailey, R.J. Barlow, G. Jackson, G.D. Lafferty, T.J. West, J. Anderson, R. Cenci, A. Jawahery, D.A. Roberts, G. Simi, J.M. Tuggle, C. Dallapiccola, E. Salvati, R. Cowan, D. Dujmic, P.H. Fisher, G. Sciolla, R.K. Yamamoto, M. Zhao, P.M. Patel, S.H. Robertson, M. Schram, P. Biassoni, A. Lazzaro, V. Lombardo, F. Palombo, S. Stracka, L. Cremaldi, R. Godang, R. Kroeger, P. Sonnek, D.J. Summers, H.W. Zhao, X. Nguyen, M. Simard, P. Taras, G. De Nardo, D. Monorchio, G. Onorato, C. Sciacca, G. Raven, H.L. Snoek, C.P. Jessop, K.J. Knoepfel, J.M. LoSecco, W.F. Wang, L.A. Corwin, K. Honscheid, R. Kass, J.P. Morris, A.M. Rahimi, N.L. Blount, J. Brau, R. Frey, O. Igonkina, J.A. Kolb, R. Rahmat, N.B. Sinev, D. Strom, J. Strube, E. Torrence, G. Castelli, E. Feltresi, N. Gagliardi, M. Margoni, M. Morandin, M. Posocco, M. Rotondo, F. Simonetto, R. Stroili, E. Ben Haim, G.R. Bonneaud, H. Briand, J. Chauveau, O. Hamon, P. Leruste, G. Marchiori, J. Ocariz, J. Prendki, S. Sitt, M. Biasini, E. Manoni, C. Angelini, G. Batignani, S. Bettarini,G. Calderini, M. Carpinelli, A. Cervelli, F. Forti, M.A. Giorgi, A. Lusiani, N. Neri, E. Paoloni, G. Rizzo, J.J. Walsh, D. Lopes Pegna, C. Lu, J. Olsen, A.J.S. Smith, A.V. Telnov, F. Anulli, E. Baracchini, G. Cavoto, R. Faccini, F. Ferrarotto, F. Ferroni, M. Gaspero, L. Li Gioi, M.A. Mazzoni, G. Piredda, F. Renga, M. Ebert, T. Hartmann, T. Leddig, H. Schroder, R. Waldi, T. Adye, B. Franek, E.O. Olaiya, F.F. Wilson, S. Emery, G. Hamel de Monchenault, G. Vasseur, C. Yeche, M. Zito, M.T. Allen, D. Aston, D.J. Bard, R. Bartoldus, J.F. Benitez, C. Cartaro, M.R. Convery, J. Dorfan, G.P. Dubois-Felsmann, W. Dunwoodie, R.C. Field, M. Franco Sevilla, B.G. Fulsom, A.M. Gabareen, M.T. Graham, P. Grenier, C. Hast, W.R. Innes, M.H. Kelsey, H. Kim, P. Kim, M.L. Kocian, D.W.G.S. Leith, S. Li, B. Lindquist, S. Luitz, V. Luth, H.L. Lynch, D.B. MacFarlane, H. Marsiske, D.R. Muller, H. Neal, S. Nelson, C.P. O’Grady, I. Ofte, M. Perl, B.N. Ratcliff, A. Roodman, A.A. Salnikov, V. Santoro, R.H. Schindler, J. Schwiening, A. Snyder, D. Su, M.K. Sullivan, K. Suzuki, J.M. Thompson, J. Vavra, A.P. Wagner, M. Weaver, C.A. West, W.J. Wisniewski, M. Wittgen, D.H. Wright, H.W. Wulsin, A.K. Yarritu, C.C. Young, V. Ziegler, X.R. Chen, W. Park, M.V. Purohit, R.M. White, J.R. Wilson, S.J. Sekula, M. Bellis, P.R. Burchat, A.J. Edwards, T.S. Miyashita, S. Ahmed, M.S. Alam, J.A. Ernst, B. Pan, M.A. Saeed, S.B. Zain, N. Guttman, A. Soffer, P. Lund, S.M. Spanier, R. Eckmann, J.L. Ritchie, A.M. Ruland, C.J. Schilling, R.F. Schwitters, B.C. Wray, J.M. Izen, X. C. Lou, F. Bianchi, D. Gamba, M. Pelliccioni, M. Bomben, G. Della Ricca, L. Lanceri, L. Vitale, V. Azzolini, N. Lopez March, F. Martinez Vidal, D.A. Milanes, A. Oyanguren, J. Albert, S. Banerjee, H.H.F. Choi, K. Hamano, G.J. King, R. Kowalewski, M.J. Lewczuk, I.M. Nugent, J.M. Roney, R.J. Sobie, T.J. Gershon, P.F. Harrison, J. Ilic, T.E. Latham, G.B. Mohanty, E.M.T. Puccio, H.R. Band, X. Chen, S. Dasu, K.T. Flood, Y. Pan, M. Pierini, R. Prepost, C.O. Vuosalo, S.L. Wu. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 104:19(2010), pp. 191801.1-191801.7.

Test of lepton universality in Upsilon(1S) decays at BaBar

P. Biassoni;A. Lazzaro;F. Palombo;N. Neri;
2010

Abstract

The ratio $R_{\tau\mu}(\Upsilon(1S)) = \Gamma_{\Upsilon(1S)\to\tau^+\tau^-}/\Gamma_{\Upsilon(1S)\to\mu^+\mu^-}$ is measured using a sample of $(121.8\pm1.2)\times10^6$ $\Upsilon(3S)$ events recorded by the BABAR detector. This measurement is intended as a test of lepton universality and as a search for a possible light pseudoscalar Higgs boson. In the standard model (SM) this ratio is expected to be close to 1. Any significant deviations would violate lepton universality and could be introduced by the coupling to a light pseudoscalar Higgs boson. The analysis studies the decays $\Upsilon(3S)\to\Upsilon(1S)\pi^+\pi^-$, $\Upsilon(1S)\to l^+l^-$, where $l=\mu,\tau$. The result, $R_{\tau\mu}(\Upsilon(1S)) = 1.005 \pm 0.013(stat.) \pm 0.022(syst.)$, shows no deviation from the expected SM value, while improving the precision with respect to previous measurements.
lepton universality
Settore FIS/04 - Fisica Nucleare e Subnucleare
2010
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/151108
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