Download or read book Photon and gluon radiative weak decays and the inclusive decays of the charmed and bottom mesons written by H. C. Lee and published by . This book was released on 1982 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Signal ai a informat s ii a written by and published by . This book was released on 1982 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of Inclusive Radiative B Meson Decay B X s Gamma written by and published by . This book was released on 2006 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiative decays of the B meson, B 2!X{sub s}[gamma], proceed via virtual flavor changing neutral current processes that are sensitive to contributions from high mass scales, either within the Standard Model of electroweak interactions or beyond. In the Standard Model, these transitions are sensitive to the weak interactions of the top quark, and relatively robust predictions of the inclusive decay rate exist. Significant deviation from these predictions could be interpreted as indications for processes not included in the minimal Standard Model, like interactions of charged Higgs or SUSY particles. The analysis of the inclusive photon spectrum from B 2!X{sub s}[gamma] decays is rather challenging due to high backgrounds from photons emitted in the decay of mesons in B decays as well as ee− annihilation to low mass quark and lepton pairs. Based on 88.5 million B{bar B} events collected by the BABAR detector, the photon spectrum above 1.9 GeV is presented. By comparison of the first and second moments of the photon spectrum with QCD predictions (calculated in the kinetic scheme), QCD parameters describing the bound state of the b quark in the B meson are extracted: m{sub b} = (4.45 ± 0.16) GeV/c2; [mu]{sub {pi}}2 = (0.65 ± 0.29) GeV2. These parameters are useful input to non-perturbative QCD corrections to the semileptonic B decay rate and the determination of the CKM parameter.

Download or read book Soft gluon Effects in Charmed meson Decays written by and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In D°- and F-meson decays, QCD effects are expected to activate W-exchange processes (quark-annihilation processes), as shown in Figs. 2 and 3, which by themselves are strongly suppressed because of helicity mismatch. For example, the D° meson, on gluon emission, can flip its spin so that the subsequent weak decay proceeds without helicity suppression. Hard-gluon emission from the D° meson, evaluated perturbatively, enhances the D° decay rate (by approx. 20%). Soft-gluon emission is an equally likely source of enhancements in charmed-meson decays, and indeed seems to be the dominant one. This soft-gluon effect in charmed-meson decays was studied by a nonperturbative method that has theoretical foundations in QCD. The basic tool is a multipole expansion in QCD. The analysis is divided into three steps: virtual color-fluctuation of charmed mesons, separation of long-distance and short-distance phenomena by use of QCD multipole expansion, and evaluation of the soft-gluon effect.

Download or read book INIS Atomindeks written by and published by . This book was released on 1987 with total page 1414 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 1118 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Inclusive Weak Decays of Charmed Mesons written by Christopher Gerald Matthews and published by . This book was released on 1993 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book List of Publications written by Atomic Energy of Canada Limited and published by . This book was released on 1976-04 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Gluon effects in charmed meson decays written by H. C. Lee and published by . This book was released on 1981 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiative Weak Decay of B meson written by Peter Chin-Wah Lo and published by . This book was released on 1987 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Energy Physics Index written by and published by . This book was released on 1994 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Weak Boson Decays Into Two Quarks Plus a Photon Or a Gluon written by Theodore R. Grose and published by . This book was released on 1980 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiative and Pionic Decays of Heavy light Mesons Using HISQ Quarks written by Maysam Emadi and published by . This book was released on 2015 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis we use the highly improved staggered quark (HISQ) formalism to study the radiative and pionic transitions of charmed mesons within the framework of lattice QCD. The HISQ action is one of the most accurate formulations of charm quarks and is a result of a perturbative Symanzik improvement program to reduce lattice discretization errors. Decay widths are calculated in numerical simulations on an ensemble of gauge field configurations with $N_f=2+1$ asqtad sea quarks generated by the MILC collaboration. In addition we study $H_ŝ\ast$ and charmonium radiative decays as well as meson electric form factors. Experimental measurements of the decay ratios of vector charmed $D̂{\ast\pm0}$ and charmed strange $D_ŝ{\ast\pm}$ mesons, show a few curious features that are of great phenomenological interest in the study of low energy hadronic physics. Unlike most mesons, the strong hadronic decay modes of $D̂{\ast0}$ and $D_ŝ{\ast\pm}$, are not dominant. However, while the neutral $D$ has a radiative mode that is competitive with its pionic mode, the charged $D$ meson's radiative decay is highly suppressed relative to that of the neutral. This suppression provides a detailed probe of strong interactions and is apparently due to an interesting near cancellation that takes place between the photon's coupling to the charm quark and to the down antiquark. The results are in agreement with all of the available experimental data, and in particular, we show that the HISQ action successfully accounts for the near cancellation of the charmed $D̂{\ast\pm}$ radiative decay. The relative suppression is demonstrated in our result for the ratio of the radiative form factors of $D$ mesons $V̂\pm(0)/V̂0(0)=0.126(36)$ computed at heavier than physical $u/d$ quark masses. The quoted errors are purely statistical. Evidence from other lattice studies indicate small systematic errors in continuum and sea quark chiral extrapolations. Valence quark chiral extrapolation increases our errors by about 50\%. A rough extrapolation suggests an agreement with the measured radiative width within $2\sigma$.

Download or read book Soft Gluon Effects in Nonleptonic Decays of Charmed Mesons written by and published by . This book was released on 1980 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soft-gluon effects in nonleptonic decays of D and F mesons are studied nonperturbatively by use of a QCD multipole expansion. For reasonable values of D-meson bound-state parameters, the soft-gluon effects lead to a significant difference in the lifetimes of the D° and D mesons.

Download or read book Weak Non leptonic Decays of Charmed Mesons in QCD Sum Rules written by B. I︠U︡ Blok and published by . This book was released on 1986 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for New Physics Using Radiative B Meson Decays and Lifetime Measurment of the B Meson with the Belle II Experiment written by Reem Rasheed and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: After the Big Bang matter and antimatter were present in equal amounts. Today, however, everything we see, is made almost entirely of matter. A fundamental ingredient to explain this asymmetry between matter and antimatter is the violation of the CP (Charge Parity) symmetry. CP violation has been observed but quantitatively not enough to explain the huge asymmetry. The Belle II experiment in Japan studies the particles produced in electron-positron collisions at the SuperKEKB collider, the highest intensity collider in the World, allowing a high precision measurements of the known sources of CP violation and looking for new ones. In my PhD, I worked on measuring the CP violation in B meson radiative decays (decays with photon in final state) particularly promising thanks to their high sensitivity to possible new processes. Following this analysis, I started a new measurement of the B mesons lifetime where I could verify the robustness of the tools used in the CP violation measurement.

Download or read book Inclusive Rare B Decays Using Effective Field Theories written by Christian Bauer and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis we will discuss several properties of rare decays of ' B' mesons. First we discuss properties of the inclusive radiative decay 'B¢' [right arrow] 'Xs'ã, where 'Xs' stands for any hadronic state containing an 's' quark. We extend previous studies of this decay, which included perturbative corrections to order Ã's' and nonperturbative contributions up to order ([Lambda]QCD/' mb')2 and calculate the O ([Lambda]QCD/'mb')3 contributions to this decay. The values of the nonperturbative parameters entering at this order are unknown, leading to uncertainties in the standard model prediction of this decay. We estimate the size of these nonperturbative uncertainties by varying these parameters in the range suggested by dimensional analysis. We also estimate uncertainties arising from a cut on the photon energy which is required experimentally. Another decay mode investigated is 'B¢' [right arrow] ' Xs'3⁄4+3⁄4-. We study the O ([Lambda]QCD/'mb')3 contributions to the leptonic invariant mass spectrum, the forward-backward asymmetry and hadronic invariant mass moments and estimate the resulting uncertainties. We calculate how the size of these uncertainties depend on the value of an experimental cut that has to be applied to eliminate the large background from other 'B' decays. A model independent way to determinate the CKM matrix element @' Vub'@ from the dilepton invariant mass spectrum of the inclusive decay B[right arrow]Xu3⁄4+ n is presented next. We show that cuts required to eliminate the charm background still allow for a theoretically clean way to determine the CKM matrix element @'Vub'@. We also discuss the utility of the 'B¢' [right arrow] 'Xs'3⁄4 +3⁄4- decay rate above the y (2'S') resonance to reduce the resulting uncertainties. Finally, we introduce a novel effective theory valid for highly energetic particles. In decays where the phase space is sufficiently restricted such that final state particles have very high energies compared to their mass, the perturbative as well as nonperturbative series diverge. The effective theory presented allows to sum perturbative Sudakov logarithms in a framework that also incorporates the nonperturbative physics in such limits of phase space.