Search for charged Higgs bosons in e +e − collisions at energies up to [formula omitted] = 189 GeV

• Published in: Physics letters. B 2000-08, Vol.487 (3), p.253-263
• Main Authors: Decamp, D., Lees, J.-P., Martin, F., Merle, E., Fernandez-Bosman, M., Paneque, D., Ruiz, H., Colaleo, A., Creanza, D., De Filippis, N., Nuzzo, S., Raso, G., Selvaggi, G., Tempesta, P., Tricomi, A., Zito, G., Xue, S., Dissertori, G., Forty, R.W., Greening, T.C., Hansen, J.B., Harvey, J., Janot, P., Ranjard, F., Rolandi, L., Schneider, O., Spagnolo, P., Teubert, F., Badaud, F., Gay, P., Michel, B., Podlyski, F., Hansen, J.D., Kyriakis, A., Simopoulou, E., Blondel, A., Tanaka, R., Focardi, E., Zachariadou, K., Antonelli, M., Bologna, G., Laurelli, P., Murtas, F., Pepe-Altarelli, M., Kennedy, J., O'Shea, V., Smith, D., Tittel, K., Beuselinck, R., Marinelli, N., Thompson, J.C., Buck, P.G., Clarke, D.P., Foster, F., Kleinknecht, K., Müller, A.-S., Nürnberger, H.-A., Renk, B., Schmeling, S., Wachsmuth, H., Zeitnitz, C., Ziegler, T., Curtil, C., Payre, P., Tilquin, A., Aleppo, M., Dietl, H., Ganis, G., Heister, A., Settles, R., Wiedenmann, W., Boucrot, J., Grivaz, J.-F., Heusse, Ph, Serin, L., Giassi, A., Sciabà, A., Blair, G.A., Green, M.G., von Wimmersperg-Toeller, J.H., Colas, P., Faı̈f, G., Lançon, E., Locci, E., Rander, J., Seager, P., Loomis, C., Kim, H.Y., Konstantinidis, N., McNeil, M.A., Combley, F., Hodgson, P.N., Affholderbach, K., Misiejuk, A., Cranmer, K., Elmer, P., Kile, J., McNamara III, P.A., Pan, Y.B., Saadi, Y.
• Format: Article
• Language: English
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/S0370-2693(00)00822-4

The data collected at centre-of-mass energies of 188.6 GeV by ALEPH at LEP, corresponding to an integrated luminosity of 176.2 pb −1, are analysed in a search for pair-produced charged Higgs bosons H ±. Three analyses are employed to select the τ +ν ττ − ν ̄ τ , c s ̄ τ − ν ̄ τ and c s ̄ s c ̄ final states. No evidence for a signal is found. Upper limits are set on the production cross section as a function of the branching fraction B( H +→τ +ν τ) and of the mass m H ± , assuming that the sum of the branching ratios is equal to one. In the framework of a two-Higgs-doublet model, charged Higgs bosons with masses below 65.4 GeV/ c 2 are excluded at 95% confidence level independently of the decay mode.