The Electron Spectrum From B-meson Decays

Wachs, K.; Antreasyan, D.; Bartels, H. W.; Bieler, C.; Bienlein, J. K.; Bizzeti, Andrea; Bloom, E. D.; Brockmuller, K.; Cartacci, A.; Cavallisforza, M.; Clare, R.; Compagnucci, A.; Conforto, G.; Cooper, S.; Coyne, D.; Drews, G.; Fairfield, K.; Folger, G.; Fridman, A.; Gelphman, D.; Glaser, G.; Godfrey, G.; Graaf, K.; Heimlich, F. H.; Heinsius, F. H.; Hofstadter, R.; Irion, J.; Jakubowski, Z.; Karch, K.; Keh, S.; Kiel, T.; Kilian, H.; Kirkbride, I.; Kobel, M.; Koch, W.; Konig, A. C.; Konigsmann, K.; Kruger, S.; Landi, G.; Leffler, S.; Lekebusch, R.; Litke, A. M.; Lowe, S.; Lurz, B.; Marsiske, H.; Maschmann, W.; Mcbride, P.; Meyer, H.; Muryn, B.; Metzger, W. J.; Monteleoni, B.; Niczyporuk, B.; Nowak, G.; Peck, C.; Pegel, C.; Pelfer, P. G.; Porter, F. C.; Reidenbach, M.; Scheer, M.; Schmitt, P.; Schotanus, J.; Schutte, J.; Schwarz, A.; Selonke, F.; Sievers, D.; Skwarnicki, T.; Stock, V.; Strauch, K.; Strohbusch, U.; Tompkins, J.; Vanuitert, B.; Vandewalle, R. T.; Voigt, A.; Volland, U.; Wacker, K.; Walk, W.; Wegener, H.; Williams, D.

doi:10.1007/BF01565126

The Crystal Ball Collaboration has measured the energy spectrum of electrons from semileptonic B meson decays at the e+ e– storage ring DORIS II. Branching ratios and weak mixing angles of the Kobayashi-Maskawa matrix are determined using several models for the hadronic matrix elements. We obtain the branching ratio for semileptonic B decays to charmed states BR(B -> e nu Xc )=(11.7+-0.4+-1.0)%. Our result for the corresponding Kobayashi-Maskawa matrix element is |Vcb |=0.052+-0.006. The model dependence of both results is included in the error. We have not observed semileptonic B decays to non-charmed mesons. Analyzing the measured electron spectrum above 2.4 GeV, where no b->c decays contribute, we find BR(B -> e nu Xu )/BR(B -> e nu Xc )<6.5% at the 90% confidence level.this corresponds to an upper limit |V ub /V cb |<

The Electron Spectrum From B-meson Decays / K., Wachs; D., Antreasyan; H. W., Bartels; C., Bieler; J. K., Bienlein; Bizzeti, Andrea; E. D., Bloom; K., Brockmuller; A., Cartacci; M., Cavallisforza; R., Clare; A., Compagnucci; G., Conforto; S., Cooper; D., Coyne; G., Drews; K., Fairfield; G., Folger; A., Fridman; D., Gelphman; G., Glaser; G., Godfrey; K., Graaf; F. H., Heimlich; F. H., Heinsius; R., Hofstadter; J., Irion; Z., Jakubowski; K., Karch; S., Keh; T., Kiel; H., Kilian; I., Kirkbride; M., Kobel; W., Koch; A. C., Konig; K., Konigsmann; S., Kruger; G., Landi; S., Leffler; R., Lekebusch; A. M., Litke; S., Lowe; B., Lurz; H., Marsiske; W., Maschmann; P., Mcbride; H., Meyer; B., Muryn; W. J., Metzger; B., Monteleoni; B., Niczyporuk; G., Nowak; C., Peck; C., Pegel; P. G., Pelfer; F. C., Porter; M., Reidenbach; M., Scheer; P., Schmitt; J., Schotanus; J., Schutte; A., Schwarz; F., Selonke; D., Sievers; T., Skwarnicki; V., Stock; K., Strauch; U., Strohbusch; J., Tompkins; B., Vanuitert; R. T., Vandewalle; A., Voigt; U., Volland; K., Wacker; W., Walk; H., Wegener; D., Williams. - In: ZEITSCHRIFT FÜR PHYSIK. C, PARTICLES AND FIELDS. - ISSN 0170-9739. - STAMPA. - 42:(1989), pp. 33-48. [10.1007/BF01565126]