Determination of the B̄→D*ℓν̄ decay width and
Physical Review D 67:3 (2003)
Authors:
NE Adam, JP Alexander, C Bebek, BE Berger, K Berkelman, F Blanc, V Boisvert, DG Cassel, PS Drell, JE Duboscq, KM Ecklund, R Ehrlich, L Gibbons, B Gittelman, SW Gray, DL Hartill, BK Heltsley, L Hsu, CD Jones, J Kandaswamy, DL Kreinick, A Magerkurth, H Mahlke-Krüger, TO Meyer, NB Mistry, E Nordberg, M Palmer, JR Patterson, D Peterson, J Pivarski, D Riley, AJ Sadoff, H Schwarthoff, MR Shepherd, JG Thayer, D Urner, B Valant-Spaight, G Viehhauser, A Warburton, M Weinberger, SB Athar, P Avery, H Stoeck, J Yelton, G Brandenburg, A Ershov, DYJ Kim, R Wilson, K Benslama, BI Eisenstein, J Ernst, GD Gollin, RM Hans, I Karliner, N Lowrey, MA Marsh, C Plager, C Sedlack, M Selen, JJ Thaler, J Williams, KW Edwards, R Ammar, D Besson, X Zhao, S Anderson, VV Frolov, Y Kubota, SJ Lee, SZ Li, R Poling, A Smith, CJ Stepaniak, J Urheim, S Ahmed, MS Alam, L Jian, M Saleem, F Wappler, E Eckhart, KK Gan, C Gwon, T Hart, K Honscheid, D Hufnagel, H Kagan, R Kass, TK Pedlar, JB Thayer, E von Toerne, T Wilksen, MM Zoeller, SJ Richichi, H Severini, P Skubic, SA Dytman, S Nam, V Savinov, S Chen, JW Hinson
Abstract:
In the standard model, the charged current of the weak interaction is governed by a unitary quark mixing matrix that also leads to CP violation. Measurement of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements is essential to searches for new physics, either through the structure of the CKM matrix, or a departure from unitarity. We determine the CKM matrix element |V cb | using a sample of 3×10 6 BB̄ events in the CLEO detector at the Cornell Electron Storage Ring. We determine the yield of reconstructed B̄ 0 →D* + ℓν̄ and B - D* 0 ℓν̄ decays as a function of w, the boost of the D* in the B rest frame, and from this we obtain the differential decay rate dΓ/dw. By extrapolating dΓ/dw to w = 1, the kinematic end point at which the D* is at rest relative to the B, we extract the product |V cb |ℱ(1), where ℱ(1) is the form factor at w=1. We find |V cb |ℱ(1) = 0.0431±0.0013(stat) ±0.0018(syst). We combine |V cb |ℱ(1) with theoretical results for ℱ(1) to determine |V cb | = 0.0469±0.0014(stat) ±0.0020(syst)±0.0018(theor). We also integrate the differential decay rate over w to obtain B(B̄ 0 →D * + ℓν̄ = (609±0.19±0.40)% and B(B - →D* 0 ℓν̄) = (6.50±0. 20±0.43)%. © 2003 The American Physical Society.
