Download or read book Study of B to Pi L Nu and B to Rho L Nu Decays and Determination of written by and published by . This book was released on 2011 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present an analysis of exclusive charmless semileptonic B-meson decays based on 377 million B{bar B} pairs recorded with the BABAR detector at the ? (4S) resonance. We select four event samples corresponding to the decay modes B° → ?−l+?, B+ → ?°l+?, B° → ?−l+?, and B+ → ?°l+?, and find the measured branching fractions to be consistent with isospin symmetry. Assuming isospin symmetry, we combine the two B → ?l? samples, and similarly the two B → ?l? samples, and measure the branching fractions ?(B° → ?−l+?) = (1.41 ± 0.05 ± 0.07) x 10−4 and ?(B° → ?°l+?) = (1.75 ± 0.15 ± 0.27) x 10−4, where the errors are statistical and systematic. We compare the measured distribution in q2, the momentum transfer squared, with predictions for the form factors from QCD calculations and determine the CKM matrix element.
Download or read book Study of B to Pi Ell Nu and B to Rho Ell Nu Decays and Determination of written by and published by . This book was released on 2005 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present an analysis of exclusive charmless semileptonic B-meson decays based on 83 million B{bar B} pairs recorded with the BABAR detector at the ?(4S) resonance. Using isospin symmetry, we measure branching fractions ?(B° → ?−l+?) = (1.38 ± 0.10 ± 0.16 ± 0.08) x 10−4 and ?(B° → ?−l+?) = (2.14 ± 0.21 ± 0.48 ± 0.28) x 10−4, where the errors are statistical, experimental systematic, and due to form-factor shape uncertainties. We compare the measured distribution in q2, the momentum-transfer squared, with theoretical predictions for the form factors from lattice QCD and light-cone sum rules, and extract the Cabibbo-Kobayashi-Maskawa (CKM) matrix element.
Download or read book Physics is Fun Memoirs of a Life in Physics written by Richard Wilson and published by Richard Wilson. This book was released on 2011 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of the B to Xclnu Decays and Determination of written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report studies of semileptonic decays, B → X{sub c}l[nu], based on a sample of 88 million B{bar B} events recorded with the BABAR detector. We have measured four moments of the electron energy and hadronic mass distributions and determined the inclusive branching fraction, the CKM matrix element.
Download or read book Issues in General Physics Research 2011 Edition written by and published by ScholarlyEditions. This book was released on 2012-01-09 with total page 8864 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in General Physics Research / 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about General Physics Research. The editors have built Issues in General Physics Research: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about General Physics Research in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in General Physics Research: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Study of Inclusive And Exclusive B X U L Nu Decays And the Measurement of written by and published by . This book was released on 2005 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report studies of B → X{sub u}l[nu] decays, based on a sample of 88 million B{bar B} events recorded with the BABAR detector. From both tagged and untagged B{bar B} events we have isolated inclusive charmless decays in kinematic regions for which the dominant background from B → X{sub c}l[nu] is reduced by making requirements on different variables: the electron energy E{sub l}, the momentum transfer q2, and the hadronic mass m{sub X}. Using theoretical calculations we extrapolate to the total decay rate to determine the CKM matrix element.
Download or read book Reconstruction of B D E Nu Decays and Determination of Vcb written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this analysis the decay B- --> D*° e- nu is measured. The underlying data sample consists of about 226 million B-meson pairs accumulated on the Y(4S) resonance by the BABAR detector at the asymmetric e+e- collider PEP II. The reconstruction of the decay uses the channels D*° --> D° pi°, D° --> K- pi+ and pi° --> gamma gamma. The neutrino is not reconstructed. Since the rest frame of the B meson is unknown, the boost w of the D*° meson in the B meson rest frame is estimated by w'. The w' spectrum of the data is described in terms of the partial decay width dGamma/dw given by theory and the detector simulation translating each spectrum dGamma/dw into an expectation of the measured w' spectrum. dGamma/dw depends on a form factor F(w) parameterizing the strong interaction in the decay process. To find the best descriptive dGamma/dw a fit to the data determines the following two parameters of dGamma/dw: (i) F(1)|Vcb|, the product between F at zero D*°-recoil and the Quark mixing parameter |Vcb|; (ii) rho^2, a parameter of the form factor F(w). The former parameter scales the height of dGamma/dw and rho^2 varies the shape of it. The determined values of F(1)|Vcb|, rho^2 and the branching fraction BF(B- --> D*° e- nu) are F(1)|Vcb| = (35.8 +- 0.5 +- 1.5) x 10e-03, rho^2 = (1.08 +- 0.05 +- 0.09) and BF(B- --> D*° e- nu) = (5.60 +- 0.08 +- 0.42)%, where the uncertainties are statistical and systematic, respectively. The value of BF(B- --> D*° e- nu) has been determined by an integration of dGamma/dw over the allowed w range using the fitted values of F(1)|Vcb| and rho^2.
Download or read book Analysis of B 2 omega l nu Decays With BaBar written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: As part of the BaBar project at SLAC to study the properties of B mesons, we have carried out a study of the exclusive charmless semileptonic decay mode B → [omega]l[nu], which can be used to determine the magnitude of the Cabbibo- Kobayashi-Maskawa matrix element Vub. Using simulated event samples, this study focuses on determining criteria on variables for selection of B → [omega]l[nu] signal and suppression of background from other types of BB events and continuum processes. In addition, we determine optimal cuts on variables to ensure a good neutrino reconstruction. With these selection cuts, we were able to achieve a signal-to-background ratio of 0.68 and a signal efficiency of the order of 1%. Applying these cuts to a sample of 83 million BB events recorded by BaBar in e+e- collisions at the (4S) resonance, we obtain a yield of 115 ± 19 B → [omega]l[nu] decays.
Download or read book High Energy Physics Index written by and published by . This book was released on 1991 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of the B0 to pi L nu Form Factor Shape and Branching Fraction and Determination of written by and published by . This book was released on 2006 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the results of a study of the exclusive charmless semileptonic decay, B° →?−l?, undertaken with approximately 227 million B{bar B} pairs collected at the?(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with an innovative loose neutrino reconstruction technique. We obtain partial branching fractions in 12 bins of q2, the momentum transfer squared, from which we extract the f+(q2) form-factor shape and the total branching fraction?(B° →?−l+?) = (1.46 ± 0.07{sub stat} ± 0.08{sub syst}) x 10−4. Based on a recent unquenched lattice QCD calculation of the form factor in the range q2> 16 GeV2, we find the magnitude of the CKM matrix element.
Download or read book B Decays written by Sheldon Stone and published by World Scientific. This book was released on 1992 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of b quarks has now reached a stage where it is useful to review what has been learned so far and also to look at the implications of future studies. The most important observations thus far measurement of the B lifetime, B0 B0 mixing, and the observation of b? u transitions, as well as more mundane results on hadronic and semileptonic transitions are described in detail by experimentalists who have been closely involved with the measurements. Theoretical progress in understanding b quark decays, including the mechanisms of hadronic and semileptonic decays, are described. Synthesizing the experimental and theoretical information, the authors discuss tests of the standard model and measurements of standard model parameters. Possibilities of more extensive tests using measurement of CP violation in the B system are also addressed.
Download or read book First Measurement of the B Pi Lepton Neutrino And B Rho omega Lepton Neutrino Branching Fractions written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: CLEO has studied B decays to the final states[pi][ell][nu], [rho][ell][nu], and[omega][ell][nu], where[ell]= e or[mu]. We fully reconstruct these modes using a measurement of the missing energy and momentum in each event to infer the neutrino momentum. With the B[sup 0] and B[sup+] modes combined according to isospin predictions for the relative partial widths, we obtain[Beta](B[sup 0][yields][pi][sup -][ell][sup+][nu])= (1.8[+-] 0.4[+-] 0.3[+-] 0.2) x 10[sup -4] and[Beta](B[sup 0][yields][rho][sup -][ell][sup+][nu])= (2.5[+-] 0.4[sub 0.7][sup -.5][+-] 0.5) x 10[sup -4], where the errors are statistical, systematic and the estimated model-dependence. We also estimateV[sub ub]= (3.3[+-] 0.2[sub 0.4][sup+0.3][+-] 0.7) x 10[sup -3].
Download or read book Measurement of the B Omega L Nu and B Eta L Nu Branching Fractions Using Neutrino Reconstruction written by and published by . This book was released on 2008 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present a study of the charmless semileptonic B-meson decays B →?l+? and B+ →?l+?. The analysis is based on 383 million B{bar B} pairs recorded at the?(4S) resonance with the BABAR detector. The? mesons are reconstructed in the channel? →?+?−?° and the? mesons in the channels? →?+?−?° and? →??. They measure the branching fractions?(B+ →?l+?) = (1.14 ± 0.16{sub stat} ± 0.08{sub syst}) x 10−4 and?(B+ →?l+?) = (0.31 ± 0.06{sub stat} ± 0.08{sub syst}) x 10−4.
Download or read book Measurement of the Decay B Omega L Nu with the Babar Detector and Determination of V ub written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We measure the branching fraction of the exclusive charmless semileptonic decay B 2![omega]l[nu]{sub l}, where l is either an electron or a muon, with the charged B meson recoiling against a tag B meson decaying in the charmed semileptonic modes B 2!Dl[nu]{sub {ell}} or B 2!D*{ell}[nu]{sub {nu}}. The measurement is based on a dataset of 426.1 fb−1 of ee− collisions at a CM energy of 10.58 GeV recorded with the BABAR detector at the PEP-II asymmetric B Factory located at the SLAC National Accelerator Laboratory. We also calculate the relevant B 2![omega] hadronic form factors to determine the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element.
Download or read book A Study of Semileptonic B Decays And of Lepton Flavor Violating Tau Decays at BaBar written by and published by . This book was released on 2005 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of the semileptonic B decays at BABAR is presented. The results shown include measurements of the moments of hadronic-mass and electron-energy of the decay B → X{sub c}l[nu]; a determination of the.
Download or read book Review of Radiative and Semileptonic B Decays written by and published by . This book was released on 2002 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent experimental results on radiative and semileptonic B meson decays are described. Measurements of inclusive and exclusive b 2!s[gamma] and b 2!sll− decays, and exclusive B 2![rho][gamma] and B 2!K[nu]{bar [nu]} penguin decays are presented. The extraction of.
