Download or read book Determination of the Form Factors for the Decay B0 D l nu l and of the CKM Matrix Element written by and published by . This book was released on 2006 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present a combined measurement of the Cabibbo-Kobayashi-Maskawa matrix element.
Download or read book Determination of the Form Factors for the Decay B0 to D L Nu l and of the CKM Matrix Element written by and published by . This book was released on 2007 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a combined measurement of the Cabibbo-Kobayashi-Maskawa matrix element.
Download or read book Measurement of Branching Fractions and Form Factor Parameters of B Dlnu and B D lnu Decays at BaBar written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We use a global fit to determine the form factor slopes and branching fractions of the decays B --> Dlnu and B --> D*lnu. We reconstruct Dl pairs and construct a 3-dimensional distribution binned in lepton momentum, D momentum and cosTheta(B-Dl). These kinematic variables provide good separation between the signal and background. We fit electron and muon samples separately and combine them after calculating systematic uncertainties. The form factor slopes, rhoD^2 for B --> Dlnu and rho^2 for B --> D*lnu decays, are measured to be rhoD^2 = 1.22 +- 0.04 +- 0.07 and rho^2 = 1.21 +- 0.02 +- 0.07, where the errors are statistical and systematic, respectively. Branching fractions are fitted to be B(B+ --> D0lnu) = (2.36 +- 0.03 +- 0.12) % and B(B^+ --> D*0lnu) = (5.37 +- 0.02 +- 0.21) %. We use these results to determine the products, G(1)|Vcb| = (43.8 +- 0.8 +- 2.3)*10^{-3} and F(1)|Vcb| = (35.7 +- 0.2 +- 1.2)*10^{-3} of the form factors at zero recoil and the CKM matrix element |Vcb|, from which |Vcb| can be extracted using theoretical input.
Download or read book Functional Analysis and Optimization Methods in Hadron Physics written by Irinel Caprini and published by Springer. This book was released on 2019-04-25 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book begins with a brief historical review of the early applications of standard dispersion relations in particle physics. It then presents the modern perspective within the Standard Model, emphasizing the relation of analyticity together with alternative tools applied to strong interactions, such as perturbative and lattice quantum chromodynamics (QCD), as well as chiral perturbation theory. The core of the book argues that, in order to improve the prediction of specific hadronic observables, it is often necessary to resort to methods of complex analysis more sophisticated than the simple Cauchy integral. Accordingly, a separate mathematical chapter is devoted to solving several functional analysis optimization problems. Their applications to physical amplitudes and form factors are discussed in the following chapters, which also demonstrate how to merge the analytic approach with statistical analysis tools. Given its scope, the book offers a valuable guide for researchers working in precision hadronic physics, as well as graduate students who are new to the field.
Download or read book B u2192 Dl Form Factors at Nonzero Recoil and written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the first unquenched lattice-QCD calculation of the hadronic form factors for the exclusive decay B¯→Dl???????? at nonzero recoil. We carry out numerical simulations on 14 ensembles of gauge-field configurations generated with 2+1 flavors of asqtad-improved staggered sea quarks. The ensembles encompass a wide range of lattice spacings (approximately 0.045 to 0.12 fm) and ratios of light (up and down) to strange sea-quark masses ranging from 0.05 to 0.4. For the b and c valence quarks we use improved Wilson fermions with the Fermilab interpretation, while for the light valence quarks we use asqtad-improved staggered fermions. We extrapolate our results to the physical point using rooted staggered heavy-light meson chiral perturbation theory. We then parametrize the form factors and extend them to the full kinematic range using model-independent functions based on analyticity and unitarity. We present our final results for f+(q2) and f0(q2), including statistical and systematic errors, as coefficients of a series in the variable z and the covariance matrix between these coefficients. We then fit the lattice form-factor data jointly with the experimentally measured differential decay rate from BABAR to determine the CKM matrix element,
Download or read book Measurements of the B to D Form Factors Using the Decay bar B 0 to D E bar nu e written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We measure the dependence of {bar B}° → D*e−{bar {nu}}{sub e} on the decay angles and momentum transfer. The data sample consists of ≈ 86 x 106 B{bar B}-pairs accumulated on the?(4S) resonance by the BABAR detector at the asymmetric e+e− collider PEP-II. We specify the three form factors by two ratios R1 and R2, and by a single parameter?2 characterizing the polynomial representing h{sub A1}, the function which describes the momentum-transfer dependence of the form factor A1. We determine R1, R2, and?2 using an unbinned maximum likelihood fit to the full decay distribution. The results are R{sub 1} = 1.396 ± 0.060 ± 0.035 ± 0.027, R2 = 0.885 ± 0.040 ± 0.022 ± 0.013, and?2 = 1.145 ± 0.059 ± 0.030 ± 0.035. The stated uncertainties are the statistical from the data, statistical from the size of the Monte Carlo sample and the systematic uncertainty, respectively. In addition, based on this measurement, we give an updated value for the CKM matrix element.
Download or read book Measurement of the Form Factors in the Semileptonic Decay D K oe ve written by Pauline Gagnon and published by . This book was released on 1993 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of the CKM Matrix Element verticalV sub Ub vertical with B yields rho e nu Decays written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a measurement of the branching fraction for the rare decays B[yields][rho]e[nu] and extract a value for the magnitude of V[sub ub], one of the smallest elements of the Cabibbo-Kobayashi-Maskawa quark-mixing matrix. The results are given for five different calculations of form factors used to parametrize the hadronic current in semileptonic decays. Using a sample of 55 million B[bar B] meson pairs recorded with the BABAR detector at the PEP-II e[sup+]e[sup -] storage ring, we obtain[Beta](B[sup 0][yields][rho][sup -1] e[sup+][nu])= (3.29[+-] 0.42[+-] 0.47[+-] 0.60) x 10[sup -4] andV[sub ub]= (3.64[+-] 0.22[+-] 0.25[sub -0.56][sup+0.39]) x 10[sup -3], where the uncertainties are statistical, systematic, and theoretical, respectively.
Download or read book B Decays written by Sheldon Stone and published by World Scientific. This book was released on 1992-03-27 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 Measurement of the CKM Matrix Element Vub with B Rho E Ny Decays at BABAR written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The branching fraction for B -> rho e nu decays and the CKM matrix element |Vub| is measured with semileptonic exclusive B-meson decays using approximately 55 million Upsilon(4S) -> BBbar decays collected during the years 2000 and 2001 with the BABAR detector. The result is Br(B0 -> rho- e+ nu) = (3.39 +- 0.44 +- 0.52 +- 0.60) x 10^-4, and |Vub| = (3.69 +- 0.23 +- 0.27 +0.40-0.59) x 10^-3. The quoted errors are statistical, systematic, and theoretical respectively. These are combined results obtained using five different form-factor models. Individual results are also quoted.
Download or read book D Semileptonic Form Factors and written by and published by . This book was released on 2011 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The measured partial widths of the semileptonic decays D → Kl[nu] and D → [pi]l[nu] can be combined with the form factors calculated on the lattice to extract the CKM matrix elements.
Download or read book B K and Form Factors for Semi leptonic and Radiative B Decays written by Aoife Katy Manek Bharucha and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The hadronic environment of the LHC favours the study of exclusive modes, and of these semi-leptonic and radiative B decays will play a leading role in the search for new physics (NP). A prime example is the rare decay B?K?(? K?)?+??, where the many measurable quantities offer important new tests of the Standard Model and its extensions. We de?ne sets of CP-conserving and CP-violating observables which are studied in terms of the full form factors, calculated in QCD sum rules on the light-cone (LCSR), and QCD factorisation. Those with reduced dependence on hadronic quantities and sensitivity to NP are identi?ed. In the ?rst few years of data?taking at the LHC, the focus will be on quantities which are simple to extract while maximising the available NP sensitivity. Out of three such observables, two are well known to the experimental community. However a third, one of the CP-conserving angular observables, leads to signi?cant additional constraints on parameter space. We then study form factors for rare semi-leptonic and radiative B decays to K(?) , ? and ?s mesons, combining theoretical and phenomenological constraints from Lattice QCD, LCSR, and dispersive bounds. We pay particular attention to form factor parameterisations which are based on the so-called series expansion, and study the related systematic uncertainties on a quantitative level. Finally we calculate the leading-twist O(?s?0) corrections to the B ? ? transition form factor f+ (0) in LCSR, allowing an improved determination of the CKM matrix element |Vub |.
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 Measurement of B D Form Factors in the Semileptonic Decay B D L Nu 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 measurement of R[sub 1], and R[sub 2], and [rho][sup 2], which are the three parameters used to characterize the B [yields] D*[ell][bar [nu]][sub e] form factors (A[sub 1], V, and A[sub 2]). They use 85 x 10[sup 6] B[bar B]-pairs accumulated on the [Upsilon](4S) resonance at PEP-II. In this analysis they use the decay mode [bar B][sup 0] [yields] D[sup +]*e[sup -][bar [nu]] and its charge conjugate. The D*[sup +] is reconstructed in the channel D*[sup +] [yields] D[sup 0][pi][sup +] and the D[sup 0] in the channel D[sup 0] [yields] K[sup -][pi][sup +]. They parameterize the form factors in terms of their ratios (determined by the parameters R[sub 1] and R[sub 2]) and the common slope [rho][sup 2] in the variable w (a quantity related to the momentum transfer in the decay process). These parameters are determined via an unbinned maximum likelihood fit to the distributions in four kinematic variables (three decay angles and w). The results are R[sub 1] = 1.328 [+-] 0.055 [+-] 0.025 [+-] 0.025 and R[sub 2] = 0.920 [+-] 0.044 [+-] 0.020 [+-] 0.013 for the ratios and [rho][sup 2] = 0.769 [+-] 0.l039 [+-] 0.019 [+-] 0.032 for the slope. The stated errors are the statistical uncertainty from the data, statistical uncertainty from the size of the Monte Carlo sample and the systematic uncertainty, respectively.
Download or read book Determination of the CKM matrix Element Vub from the Electron Energy Spectrum Measured in Inclusive B X U E Ypsilon Decay with the BABAR Detector written by and published by . This book was released on 2012 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determination of the CKM Matrix Element Vcb the B Xs Xsgamma Decay Rate and the B quark Mass written by Florian Urs Bernlochner and published by . This book was released on 2011 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of B D Form Factors in the Semileptonic Decay B D L Nu at BaBar written by and published by . This book was released on 2006 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present here the results of a measurement of the three semileptonic form factors involved in the decay B° → D*l?, where l is one of the two light charged leptons (i.e. an electron or muon--though the final results in this work are determined only for l = electron). This measurement uses the Babar 2000-2002 data set, which is altogether approximately 85 x 106 B{bar B}-pairs in 78 fb−1 of integrated luminosity. The D* was reconstructed in the channel D*+ → D°?+, and the D° in the channel D° → K−?+. This analysis was based ultimately on ≈ 16,386 reconstructed events with an estimated background contamination of ≈ 15%. The method of the measurement was to perform a unbinned maximum likelihood fit in the four kinematic variables that describe the decay for the three form factor parameters R1, R2, and?2. The results obtained for the form factor ratios are R1 = 1.328 ± 0.055 ± 0.025 ± 0.025 and R2 = 0.920 ± 0.044 ± 0.020 ± 0.013 for the ratios and?2 = 0.769 ± 0.039 ± 0.019 ± 0.032 for the form factor slope. The errors given are statistical, Monte Carlo statistical and systematic respectively.
