Heavy flavour production in Z decays

• Published in: Physics letters. B Vol. 244; no. 3; pp. 551 - 565
• Main Authors: Farilla, A., Nuzzo, S., Raso, G., Romano, F., Selvaggi, G., Zito, G., Jin, S., Xie, Y., Zhang, Z., Grab, C., Hagelberg, R., Lohse, T., May, J., Menary, S., Minten, A., Miotto, A., Roth, A., Rothberg, J., St.Denis, R., Taureg, H., Wotschack, J., Bardadin-Otwinowska, M., Falvard, A., Michel, B., Pallin, D., Perret, P., Hansen, J.D., Møllerud, R., Vayaki, A., Blondel, A., Bonneaud, G., Rumpf, M., Baldini, R., Felici, G., Mannocchi, G., Zografou, P., Boyle, O., Lynch, J.G., Thompson, A.S., Braun, O., Hanke, P., Kluge, E.E., Maumary, Y., Rensch, B., Tittel, K., Binnie, D.M., Cattaneo, M., Hassard, J.F., Kuhn, D., Rudolph, G., Bowdery, C.K., Brodbeck, T.J., Finch, A.J., Hughes, G., Sloan, T., Renk, B., Albanese, J.-P., Papalexiou, S., Cattaneo, P., Jahn, A., Lutz, G., Moser, H.-G., Richter, R., Stierlin, U., Thomas, J., Bertin, V., Boucrot, J., Callot, O., Ganis, G., Lutz, A.-M., Bradaschia, C., Foà, L., Focardi, E., Mannelli, E.B., Messineo, A., Steinberger, J., Tenchini, R., March, P.V., Strong, J.A., Wildish, T., Fisher, S.M., Perez, P., Rander, J., Schuller, J.-P., Booth, C.N., Combley, F., Dinsdale, M., Martin, J., Parker, D., Grupen, C., Meinhard, H., Gobbo, B., Bellantoni, L., Boudreau, J.F., Cinabro, D., Conway, J.S., Feng, Z., LeClaire, B.W., Pan, Y.B., Zobernig, G.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 26.07.1990; Elsevier
• Subjects: High Energy Physics - Experiment; Physics; persuasion; content analysis; consumer behavior; implicit attitude; advertising; Internet; political communication
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/0370-2693(90)90362-A

From an analysis of inclusive leptons in data collected by the ALEPH detector at LEP, we measure the fractions of b b and c c events in hadronic Z decays. The b b fraction times semileptonic branching ratio is measured to be Br( b → e)·Γ b b /Γ had = 0.0224 ± 0.0016 ± 0.0010 . Assuming a b semileptonic branching ratio of 0.102 ± 0.010 gives Γ b b /Γ had = 0.220 ± 0.016 ± 0.024 , in good agreement with the standard model prediction of 0.217. The c c fraction times semileptonic branching ratio is measured to be Br( c → e)·Γ c c /Γ had = 0.0133 ± 0.0040 −0.0031 +0.0038 . Assuming a c semileptonic branching ratio of 0.090 ± 0.013 gives Γ c c /Γ had = 0.148 ± 0.044 −0.038 +0.045 , in agreement with the standard model prediction of 0.171.