Flavour independent search for Higgs bosons decaying into hadronic final states in e+e− collisions at LEP

• Published in: Physics letters. B Vol. 597; no. 1; pp. 11 - 25
• Main Authors: Ainsley, C., Alexander, G., Amaral, P., Anagnostou, G., Azuelos, G., Barlow, R.J., Behnke, T., Biebel, O., Boutemeur, M., Brown, R.M., Campana, S., Carter, A.A., Carter, J.R., Chang, C.Y., Csilling, A., Cuffiani, M., Dado, S., De Roeck, A., Dubbert, J., Duchovni, E., Duerdoth, I.P., Etzion, E., Fabbri, F., Fleck, I., Ford, M., Gagnon, P., Geich-Gimbel, C., Goldberg, J., Gross, E., Günther, P.O., Gupta, A., Hanson, G.G., Harel, A., Hemingway, R.J., Hocker, A., Horváth, D., Igo-Kemenes, P., Ishii, K., Jeremie, H., Kanaya, N., Kanzaki, J., Keeler, R.K., Kellogg, R.G., Kobel, M., Krämer, T., Lafferty, G.D., Landsman, H., Layter, J.G., Letts, J., Mader, W., Marcellini, S., Masetti, G., Mashimo, T., Mättig, P., Menges, W., Mes, H., Mikenberg, G., Miller, D.J., Mori, T., Mutter, A., Nakamura, I., Nanjo, H., Neal, H.A., Okpara, A., Pahl, C., Pásztor, G., Pooth, O., Przybycień, M., Renkel, P., Roney, J.M., Rosati, S., Sachs, K., Sarkisyan, E.K.G., Schieck, J., Shen, B.C., Sherwood, P., Smith, A.M., Sobie, R., Söldner-Rembold, S., Stahl, A., Strom, D., Toya, D., Tran, P., Trigger, I., Trócsányi, Z., Vollmer, C.F., Vannerem, P., Vértesi, R., Voss, H., Vossebeld, J., Ward, C.P., Watson, A.T., Watson, N.K., Wetterling, D., Wilson, G.W., Wilson, J.A., Wolf, G., Wyatt, T.R., Yamashita, S., Zivkovic, L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 02.09.2004; Elsevier Science
• Subjects: Exact sciences and technology; Physics; The physics of elementary particles and fields; Lower bound; Branching ratio; Bound state; Higgs model; Higgs bosons; Standard model; Positron annihilation; Flavor; Cross sections
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2004.06.083

A search for the Higgsstrahlung process e+e−→hZ is described, where the neutral Higgs boson h is assumed to decay into hadronic final states. In order to be sensitive to a broad range of models, the search is performed independent of the flavour content of the Higgs boson decay. The analysis is based on e+e− collision data collected by the OPAL detector at energies between 192 and 209 GeV. The search does not reveal any significant excess over the Standard Model background prediction. Results are combined with previous searches at energies around 91 and at 189 GeV. A limit is set on the product of the cross-section and the hadronic branching ratio of the Higgs boson, as a function of the Higgs boson mass. Assuming the hZ coupling predicted by the Standard Model, and a Higgs boson decaying only into hadronic final states, a lower bound of 104 GeV/c2 is set on the mass at the 95% confidence level.