Determination of [verticalV[sub Ub][vertical in Inclusive Semileptonic B Meson Decays
Author | : |
Publisher | : |
Total Pages | : |
Release | : 2004 |
ISBN-10 | : OCLC:68497120 |
ISBN-13 | : |
Rating | : 4/5 ( Downloads) |
Download or read book Determination of [verticalV[sub Ub][vertical in Inclusive Semileptonic B Meson Decays written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present a preliminary determination of the CKM matrix element V[sub ub] based on the analysis of semileptonic B decays from a sample of 88 million [Upsilon](4S) decays collected with the BaBar detector at the e[sup +]e[sup -] storage ring. Charmless semileptonic B decays are selected using the electron energy E-e and the invariant mass q[sup 2] of the electron-neutrino pair. The neutrino meomentum is inferred from a measurement of the visible energy and momentum in the detector and knowledge of the e[sup +]e[sup -] beam momenta. The partial branching fraction is determined in a region of the q[sup 2]-E-e plane where semileptonic B decays to charm are highly suppressed. The total charmless semileptonic branching fraction is extracted using a theoretical calculation based on the heavy quark expansion. Preliminary results yield V[sub ub] = (4.57 [+-] 0.21 [+-] 0.25 [+-] 0.34 + 0.59 - 0.29 [+-] 0.22) x 10[sup -3] where the uncertainties are from statistics (data and MC), detector modeling, background modeling, the shape function, and the heavy quark operator product expansion, respectively.