2004/08/10 by B. Aubert, R. Barate, BABAR Collaboration +98 · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex
paper · pdf · doi:10.1103/physrevd.71.051502
published as Phys.Rev.D71:051502,2005 · 8 pages, 4 postscript figures, contributed to ICHEP'04, 32nd International Conference on High Energy Physics, 8/16 - 8/22/2004, Beijing, China. Submitted to Phys. Rev. D (Rapid Communications)
arxiv created 2004/08/10 · openalex publication_date 2005/03/15 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/04
We present a measurement of the Cabibbo-Kobayashi-Maskawa matrix element |Vcb| based on a sample of about 53 700 B0\ensuremath→D*+\ensuremathℓ^\ensuremath-\ensuremathν_\ensuremathℓ decays observed by the BABAR detector. We obtain the branching fraction averaged over \ensuremathℓ=e,\ensuremathμ, B(B0\ensuremath→D*+\ensuremathℓ^\ensuremath-\ensuremathν_\ensuremathℓ)=(4.90\ifmmode±\else\textpm\fi0.07(stat.)_\ensuremath-0.35+0.36(syst.))%. We measure the differential decay rate as a function of w, the relativistic boost \ensuremathγ of the D*+ in the B0 rest frame. By extrapolating d\ensuremathΓ/dw to the kinematic limit w\ensuremath→1, we extract the product of |Vcb| and the axial form factor A1(w=1). We combine this measurement with a lattice QCD calculation of A1(w=1) to determine |Vcb|=(38.7\ifmmode±\else\textpm\fi0.3(stat.)\ifmmode±\else\textpm\fi1.7(syst.)_\ensuremath-1.3+1.5(theory))\ifmmode×\else\texttimes\fi10^\ensuremath-3.