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Dissertations / Theses on the topic 'B mixing'
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1
Lai, I. Chung. "Measurement of bar{B0} Meson Properties Via Partial Reconstruction of the Decay bar{B0} -> D*+ l- ar{nu}." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/38697.
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Using data recorded by the CLEO II detector operating at the
Upsilon(4S) resonance at the Cornell Electron Storage Ring,
several properties of B mesons are measured using a partially
reconstructed tag of the decay mode bar{B0} ->
D*+ l- bar{nu}. Using 2.38 fb**{-1} of on-resonance
data and the averaged B meson semileptonic branching fraction
through inclusive lepton momentum spectrum obtained by previous
CLEO analysis, we measure the B0 and B- semileptonic
branching fraction to be (10.78 +/- 0.60 +/- 0.69)% and
(10.25 +/- 0.57 +/- 0.65)% respectively, which yields the
lifetime ratio tau_+/tau_0 = 0.950 +0.117-0.080 +0.091-0.068,
assuming the equality of semileptonic partial branching width for
bar{B0} and B-. With a larger dataset of 3.1 fb**{-1}, we measured
the B0-bar{B0} mixing parameter chi_d to be 0.189 +/- 0.019 +/- 0.006.Ph. D.
2
Di, Pierro Massimo. "B physics from lattice simulations." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297379.
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Maksimović, Petar 1968. "Observation of [pi]-B meson charge-flavor correlations and measurement of time dependent B⁰⁰ mixing in pp collisions." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47407.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1998.On t.p. "[pi]" appears as the lower case Greek letter, and the second "B" and "p" are each surmounted by a stroke.
Includes bibliographical references (p. 238-243).
by Petar Maksimović.
Ph.D.
4
Webber, Adam Dane. "Radiation damage studies in the LHCb VELO detector and measurement of the flavour-specific asymmetry in semileptonic B-decays." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/radiation-damage-studies-in-the-lhcb-velo-detector-and-measurement-of-the-flavourspecific-asymmetry-in-semileptonic-bdecays(6a41db51-8d4e-4b43-914b-80a1c73d5271).html.
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This thesis presents several studies of data collected at the LHCb detector during its first two years of operation. A detector upgrade study is first presented, using simulated events at an increased luminosity. A second study involves radiation damage to the silicon sensors of the LHCb Vertex Locator. During 2010 and 2011the silicon sensors were exposed to a range of fluences, with sensors in the mostactive regions exposed to fluences of up to approximately 45x10^12 1MeV neutron equivalent (1MeV neq). The first observation of n+-on-n sensor type inversion at the Large Hadron Collider is reported, occurring at a fluence of around (10-15)x10^12 of 1MeV neq. The effective depletion voltages of the only n+-on-p sensors in use at the Large Hadron Collider have also been studied, with decreases of around 25V observed after initial irradiation. Following this, the effective depletion voltage inn+-on-p type sensors is observed to increase at a comparable rate to type inverted n+-on-n type sensors. A reduction in the charge collection efficiency due to an unexpected effect involving the sensor readout lines is also observed. A third study relates to CP violation in neutral B-meson mixing, by the measurement of the flavour-specific asymmetry. In the Standard Model, CP violation from this source is expected to be of order 10^-4. Any measured enhancement of this would be a strong indication of new physics. The DØ collaboration has measured the flavour specific asymmetry from B0 and B0s mixing, and found it to be inconsistent with the Standard Model at a confidence level of 3.9 standard deviations, thus motivating an independent measurement from the LHCb experiment. Using the full 2011 LHCb dataset, corresponding to 1.0 fb^-1 of recorded luminosity, the B0s-meson component of the flavour-specific asymmetry is measured to be afs_s = (-0.12 +/- 0.48 +/- 0.34)%, where the first uncertainty is statistical and the second is systematic. This is the single most accurate measurement of afs_s, and is consistent with both the DØ measurement and the Standard Model prediction.
5
Bird, Thomas. "Flavour studies with LHCb : b-meson mixing, lepton-flavour violation and the velo upgrade." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/flavour-studies-with-lhcb-bmeson-mixing-leptonflavour-violation-and-the-velo-upgrade(7a8a7cf6-4885-4bc3-80b7-8208d606cf9f).html.
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Semileptonic B decays of the type Bq⁰→Dq⁻μ⁺ν (where Dq⁻→K⁻K⁺pie⁻) are selected and their lifetimes are corrected using a statistical simulation-based correction called the k-factor. Using 1 fb⁻¹ of LHCb data the B⁰ and Bs⁰ mixing frequencies are measured to be Deltamd = ( 0.503 ± 0.011 (stat) ± 0.013 (syst) ) ps⁻¹ and Deltams = ( 17.93 ± 0.22 (stat) ± 0.15 (syst) ) ps⁻¹. We exclude the null hypothesis of no mixing for the B⁰ and Bs⁰ by 5.8 and 13.0 standard deviations respectively. This is the first observation of Bs Bsbar mixing using only semileptonic B decays. The lepton flavour violating decay D⁰→eμ is searched for, using tagged D⁰ decays from D*→D⁰pie, and the measurement is normalised using D⁰→K⁻pie⁺ decays. No evidence is seen of an excess over the expected background and so a limit is placed B(D⁰→eμ) < 1.3×10⁻⁸ at a 90% confidence level using 3 fb⁻¹ of LHCb data. This improves the previous measurement by a factor of 20 and is the world's best measurement. Possible upgrades to the LHCb VELO detector are simulated and aspects of the upgraded detector are optimised to ensure that all tracks within the angular acceptance can be detected with high precision. Finally the simulated performance of the current and upgraded VELO detectors are compared.
6
James, Eric B. "Measurement of the neutral B meson-neutral anti-B meson mixing parameter using dimuon events collected with the D-zero detector." Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187451.
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The DØ experiment at Fermilab has determined the B meson-neutral anti-B meson mixing probability X using dimuon events produced in proton anti-proton collisions at √s = 1.8 TeV. Using a sample of 183 dimuon events, we have determined the time and flavor averaged mixing probability X to be 0.09 ± 0.04(stat) ± 0.03(sys) in agreement with the present world average for this parameter.
7
Leitner, Olivier Michel André. "Direct CP violation in B decays including \rho - \omega mixing and covariant light-front dynamics." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2003. http://tel.archives-ouvertes.fr/tel-00003690.
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Lambert, Robert William. "LHCb hybrid photon detectors and sensitivity to flavour specific asymmetry in neutral B-Meson mixing." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/3951.
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The Large Hadron Collider started operation this year, 2008. LHCb is a precision heavy-flavour experiment at this collider. The precision of LHCb is greatly aided by the LHCb Ring Imaging Cherenkov system for the separation and identification of charged hadrons. This system uses pixel Hybrid Photon Detectors, an innovative new technology for single photon imaging. The simulation and testing of these photon detectors are reported and discussed. The photodetectors were measured to have reached or exceeded the specifications in key areas. In particular, the detector quantum efficiencies far exceed expectations, by a relative 27 %. The precision of LHCb will be used to examine CP-violation and rare decays of B-mesons. A key part of the physics programme will be a measurement of the CP-violating flavour specific asymmetry in neutral B-meson mixing. This asymmetry is expected to be very small in the Standard Model, of order 10-4, however it is very sensitive to new physics, which can increase the asymmetry dramatically. We present an improved event selection and a novel method to control systematics. This will enable us to make a world-leading measurement of this parameter in one nominal year of data taking (2 fb-1).
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Villa, Andrea. "Measurement of y_CP with D^0 mesons from semileptonic B-meson decays at LHCb." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21249/.
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This thesis reports a measurement of the charm-mixing observable yCP using D^0->K^+K^−, D^0->pi^+pi^−, and D^0->K^−pi^+ decays, where the D^0 meson originates from semileptonic B-meson decays. The analysis is performed on the full Run 2 dataset collected by LHCb with pp collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.57 fb^−1 . The dataset is divided into 18 exclusive D^0 decay-time bins, in which an invariant mass fit is performed to extract the signal yield for each decay channel. The ratios of KK/Kpi and pipi/Kpi yields in each bin, corrected for the efficiency as function of the decay-time estimated from a Monte Carlo sample, are then fitted to extract the difference between the decay widths of KK (pipi) and Kpi channels, ∆Γ^{KK} (∆Γ^{pipi}). Finally, y_CP is computed as ∆Γt(D^0), where t(D^0) is the precisely known D^0 lifetime. The values obtained from the two decay channels with preliminary systematic uncertainties are y_CP^{KK} = (75.98 ± 0.07 (stat) ± 0.06 (syst))%, y_CP^{pipi} = (76.29 ± 0.14 (stat) ± 0.05 (syst))%, which are consistent with each other (the central values are blind), and when combined yield a result of y_CP = (76.08 ± 0.06 (stat) ± 0.04 (syst))%. The analysis aims at updating the previous LHCb measurement with a larger data sample size, and is expected to improve the precision by a factor two with respect to the current world average y_CP = (0.715 ± 0.111)%.
10
Davis, Adam C. "Search for Mixing and Charge Parity Violation in Neutral Charm Mesons through Semileptonic B Meson Decay." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1470671480.
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Stahl, Thorsten. "Prospects for measuring the BOs mixing parameter Dms [Delta ms] using the decay channel B0s -> D-sa+1 with the ATLAS detector." Aachen Shaker, 2008. http://d-nb.info/992916739/04.
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Volk, Alexei. "Measurement of the Partial Branching Fraction for Inclusive Semileptonic B Meson Decays to Light Hadrons B->Xu l nu and an Improved Determination of the Quark-Mixing Matrix Element |V_ub|." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-24169.
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This thesis presents an analysis of inclusive semileptonic $B \to X_u e \nu$ decays using approximately 454 million $\Upsilon(4S) \to B \bar{B}$ decays collected during the years 1999 to 2008 with the BABAR detector.
The electron energy, $E_e$, and the invariant mass squared of the electron-neutrino pair,$ q^2$, are reconstructed, where the neutrino kinematics is deduced from the decay products of both B mesons.
The final hadronic state,$ X_u$, consists of a sum of many hadronic channels, each of which contains at least one $u$ quark.
The variables $q^2$ and $E_e$ are then combined to compute the maximum kinematically allowed invariant mass squared of the hadronic system, $s_h^{max}$.
Using these kinematic quantities, the partial branching fraction, $\Delta BR(B \to X_u e \nu)$, unfolded for detector effects, is measured to be
$\Delta BR(E_e>2.0 GeV, s_h^{max}<3.52 GeV^2) = (3.33 \pm 0.18 \pm 0.21) \times 10^{-4}
in the $\Upsilon(4S)$ and
\Delta \tilde{\BR}(\tilde E_e>1.9 GeV, \tilde {s}^{max}_{h} < 3.5 GeV^2) = (4.57 \pm 0.24 \pm 0.32) \times 10^{-4}
in the $B$ meson rest frames. The quoted errors are statistical and systematic, respectively.
The CKM matrix element $|V_{ub}|$ is determined from the measured $\Delta \tilde{\BR}$ using theoretical calculation based on Heavy Quark Expansion. The result is
$|V_{ub}| = (4.19 \pm 0.18{}^{+0.26}_{-0.20} {}^{+0.26}_{-0.25}) \times 10^{-3}, where the errors represent experimental uncertainties, uncertainties from HQE parameters and theoretical uncertainties, respectively.
13
Kanso, Walaa. "Analyse du canal B⁰s→J/ψK∗⁰ et contraintes sur les processus pingouins dans les désintégrations B⁰s→J/ψφ auprès du détecteur LHCb." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4043.
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La désintégration B⁰s→J/ψφ peut se faire suivant deux processus principaux: l'arbre et les pingouins sous-dominants. Négligée jusqu'à maintenant, la contribution des diagrammes pingouins doit être contrôlée afin d'isoler les effets du Modèle Standard de l'éventuelle présence de Nouvelle Physique dans la mesure de la phase φs. Nous avons étudié le canal B⁰s→J/ψK∗⁰ dans lequel les diagrammes pingouins ne sont pas négligeables par rapport à l'arbre. Avec 3 fb⁻¹ de données enregistrées par LHCb, nous avons mesuré le rapport démbranchement: B(B⁰s→J/ψK∗⁰)=(4.17±0.18(stat)±0.26(syst)±0.24(fd/fs))×10−5, où fd(s) est la fraction de production du méson B0(B0s). Nous avons effectué une analyse angulaire des produits de désintégrations J/ψ et K*⁰ afin déxtraire les fractions de polarisations et, pour la première fois, l'asymétrie CP en fonction des différents états de polarisations de l'état final. Les asymétries CP directes mesurées sont nulles, comme prédit par le Modèle Standard. Nous avons mesuré: f0 =0.497⁺⁰⋅⁰²⁴₋₀⋅₀₂₅(stat)±0.025(syst) et f‖=0.179⁺⁰⋅⁰²⁷₋₀⋅₀₂₆(stat)±0.013(syst). Nous avons déterminé les premières contraintes sur les diagrammes pingouins dans la phase φs en utilisant le canal B⁰s→J/ψK∗⁰. En combinant avec le canal B⁰→J/ψρ⁰, la déviation sur la phase φs due aux processus pingouins, est inférieure à 19mrad pour les trois polarisations. L'effet des processus pingouins est donc suffisamment petit pour que la mesure de la phase φs (σφs=35mrad) demeure une des mesures phares de LHCb dans les années à venir, pour rechercher de la Nouvelle PhysiqueWithin the Standard Model, the decay B⁰s→J/ψφ can occur via two main processes: the predominant tree and the sub-leading penguin. Penguin contributions have been so far ignored. Controlling them is crucial in order to disentangle Standard Model effects from possible New Physics in the measurement of φs. We studied the B⁰s→J/ψK∗⁰ channel where penguin diagrams are not negligible compared to tree. Using 3 fb⁻¹ of data collected by LHCb, we measured the branching ratio: B(B⁰s→J/ψK∗⁰)=(4.17±0.18(stat)±0.26(syst)±0.24(fd/fs))×10−5, where fd(s) is the production fraction of the B⁰(B⁰s) meson. We performed an angular analysis of the decay products J/ψ and K∗⁰ to extract the polarisation fractions and the first estimate of the polarization-dependent direct CP asymmetry. Our results show no evidence for direct CP violation in B⁰s→J/ψK∗⁰, as expected in the Standard Model. We measured: f0=0.497⁺⁰⋅⁰²⁴₋₀⋅₀₂₅(stat)±0.025(syst) and f‖=0.179⁺⁰⋅⁰²⁷₋₀⋅₀₂₆(stat)±0.013(syst). We determined the first constraints on penguin diagrams in φs phase using the B⁰s→J/ψK∗⁰ channel. Combining with the B⁰→J/ψρ⁰ decays, the shift on φs, due to penguin processes, is below 19mrad for the three polarizations. The effect of penguin processes is therefore sufficiently small to keep the φs measurement (σφs=35mrad) among the top priorities of LHCb for the upcoming years, to search for New Physics
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Khanji, Basem. "Recherche de nouvelle physique dans le canal B⁰ → J/ψφ auprès de l’expérience LHCb." Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX22064.
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Dans le Modèle Standard, la différence de phase apparaissant dans la désintégration B0s --> J/psi phi est prèdite avec une grande précision. Cette observable est une sonde pour mettre en évidence de la Nouvelle Physique car l’oscillation B0s -B0sbar s’effectue via un diagramme en boucles sensible à la nouvelles particules. Nous avons développé une sélection simplifiée pour les données de 2010. Elle évite tous biais sur la distribution en temps propre afin de réduire l’incertitude systématique. De plus, nous contrôlons les performances d’étiquetage pour les événements B0s --> J/psi phi en utilisant les canaux similaires B0d--> J/psi K*0 et B+ --> J/psi K+. Avec les données de 2010, nous obtenons 570 événements de signal avec une luminosité intégré de 36 pb−1, une puissance de d’étiquetage de (2, 2 ± 0, 4)% et une résolution temporelle de 50 fs. Nous avons étudié une sélection alternative, qui maximise la sensibilité à la phase phis en utilisant des coupures biasant le temp propre. Nous avons proposé une méthode pour corriger la déformation de temps propre à partir des données. Nous avons développé un programme d’ajustement pour déterminer la phase phis. Avec les données 2010, la valeur touvée est phis = [−2, 7,−0, 5] rad à 68% de confiance. Ce résultat est compatible avec la prédiction du Modèle StandardIn the PsB $to$ PJpsi $phi$ channel, the phase difference phis between decays with and without oscillation is predicted to be significantly small in the SM. Furthermore, the PsB-PasB mixing phenomena takes place via a loop diagram. These two reasons makes the phis parameter an excellent probe for New Physics processes. We developed a simplified selection for the 2010 data. It avoids any bias on the proper time distribution in order to reduce systematic uncertainty. In addition, we control the tagging performance for PsB $to$ PJpsi $phi$ events using the similar $PBdtoPJpsiPKstar^0$ and $PButoPJpsiPKplus$ channels. With the 2010 data, we obtain $570$ signal events in $36invpb$ of integrated luminosity, a tagging power of $(2.2pm 0.4)%$ and a proper time resolution of $50fs$. We investigated an alternative selection which is designed to maximize the phis sensitivity using a proper time biasing cuts. We proposed a data-driven method to correct the proper time acceptance. We designed a fitting program to determine the phis phase. Using fast Monte Carlo simulation we validated the fitter program, determine the LHCb sensitivity to the phis phase and advise the use of interval estimate at low signal yield. We reviewed the first determination of the phis phase by the LHCb collaboration. It is found to be: $phis in [-2.7,-0.5] rad ~ {rm at~68%~CL}$. This result is compatible with the Standard Model prediction
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Schubert, Jens. "Reconstruction of B- --> D*° e- nu Decays and Determination of |Vcb|." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1169731847466-67149.
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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.
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Hadrich, Ben Arab Atizez. "Étude des fonctions B-splines pour la fusion d'images segmentées par approche bayésienne." Thesis, Littoral, 2015. http://www.theses.fr/2015DUNK0385/document.
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Dans cette thèse nous avons traité le problème de l'estimation non paramétrique des lois de probabilités. Dans un premier temps, nous avons supposé que la densité inconnue f a été approchée par un mélange de base B-spline quadratique. Puis, nous avons proposé un nouvel estimateur de la densité inconnue f basé sur les fonctions B-splines quadratiques, avec deux méthodes d'estimation. La première est base sur la méthode du maximum de vraisemblance et la deuxième est basée sur la méthode d'estimation Bayésienne MAP. Ensuite, nous avons généralisé notre étude d'estimation dans le cadre du mélange et nous avons proposé un nouvel estimateur du mélange de lois inconnues basé sur les deux méthodes d'estimation adaptées. Dans un deuxième temps, nous avons traité le problème de la segmentation statistique semi supervisée des images en se basant sur le modèle de Markov caché et les fonctions B-splines. Nous avons montré l'apport de l'hybridation du modèle de Markov caché et les fonctions B-splines en segmentation statistique bayésienne semi supervisée des images. Dans un troisième temps, nous avons présenté une approche de fusion basée sur la méthode de maximum de vraisemblance, à travers l'estimation non paramétrique des probabilités, pour chaque pixel de l'image. Nous avons ensuite appliqué cette approche sur des images multi-spectrales et multi-temporelles segmentées par notre algorithme non paramétrique et non superviséIn this thesis we are treated the problem of nonparametric estimation probability distributions. At first, we assumed that the unknown density f was approximated by a basic mixture quadratic B-spline. Then, we proposed a new estimate of the unknown density function f based on quadratic B-splines, with two methods estimation. The first is based on the maximum likelihood method and the second is based on the Bayesian MAP estimation method. Then we have generalized our estimation study as part of the mixture and we have proposed a new estimator mixture of unknown distributions based on the adapted estimation of two methods. In a second time, we treated the problem of semi supervised statistical segmentation of images based on the hidden Markov model and the B-sline functions. We have shown the contribution of hybridization of the hidden Markov model and B-spline functions in unsupervised Bayesian statistical image segmentation. Thirdly, we presented a fusion approach based on the maximum likelihood method, through the nonparametric estimation of probabilities, for each pixel of the image. We then applied this approach to multi-spectral and multi-temporal images segmented by our nonparametric and unsupervised algorithm
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Schubert, Jens. "Reconstruction of B- --> D*° e- nu Decays and Determination of |Vcb|." Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A25025.
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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.
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Mortada, Hassan. "Separation of parameterized and delayed sources : application to spectroscopic and multispectral data." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAD051/document.
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Ce travail est motivé par la spectroscopie de photoélectrons et l'étude de la cinématique des galaxies où les données correspondent respectivement à une séquence temporelle de spectres et à une image multispectrale. L'objectif est d'estimer les caractéristiques (amplitude, position spectrale et paramètre de forme) des raies présentes dans les spectres, ainsi que leur évolution au sein des données. Dans les applications considérées, cette évolution est lente puisque deux spectres voisins sont souvent très similaires : c'est une connaissance a priori qui sera prise en compte dans les méthodes développées. Ce problème inverse est abordé sous l'angle de la séparation de sources retardées, où les spectres et les raies sont attribués respectivement aux mélanges et aux sources. Les méthodes de l'état de l'art sont inadéquates car elles supposent la décorrélation ou l'indépendance des sources, ce qui n'est pas le cas. Nous tirons parti de la connaissance des sources pour les modéliser par une fonction paramétrique. Nous proposons une première méthode de moindres carrés alternés : les paramètres de formes sont estimés avec l'algorithme de Levenberg-Marquardt, tandis que les amplitudes et les positions sont estimées avec un algorithme inspiré d'Orthogonal Matching Pursuit. Une deuxième méthode introduit un terme de régularisation pour prendre en compte l'évolution lente des positions; un nouvel algorithme d'approximation parcimonieuse conjointe est alors proposée. Enfin, une troisième méthode contraint l'évolution des amplitudes, positions et paramètres de forme par des fonctions B-splines afin de garantir une évolution lente conforme au physique des phénomènes observés. Les points de contrôle des B-splines sont estimés par un algorithme de moindre carrés non-linéaires. Les résultats sur des données synthétiques et réelles montrent que les méthodes proposées sont plus efficaces que les méthodes de l'état de l'art et aussi efficaces qu'une méthode bayésienne adaptée au problème mais avec un temps de calcul sensiblement réduitThis work is motivated by photoelectron spectroscopy and the study of galaxy kinematics where data respectively correspond to a temporal sequence of spectra and a multispectral image. The objective is to estimate the characteristics (amplitude, spectral position and shape) of peaks embedded in the spectra, but also their evolution within the data. In the considered applications, this evolution is slow since two neighbor spectra are often very similar: this a priori knowledge that will be taken into account in the developed methods. This inverse problem is approached as a delayed source separation problem where spectra and peaks are respectively associated with mixtures and sources. The state-of-the-art methods are inadequate because they suppose the source decorrelation and independence, which is not the case. We take advantage of the source knowledge in order to model them by a parameterized function. We first propose an alternating least squares method: the shape parameters are estimated with the Levenberg-Marquardt algorithm, whilst the amplitudes and positions are estimated with an algorithm inspired from Orthogonal Matching Pursuit. A second method introduces a regularization term to consider the delay slow evolution; a new joint sparse approximation algorithm is thus proposed. Finally, a third method constrains the evolution of the amplitudes, positions and shape parameters by B-spline functions to guarantee their slow evolution. The B-spline control points are estimated with a non-linear least squares algorithm. The results on synthetic and real data show that the proposed methods are more effective than state-of-the-art methods and as effective as a Bayesian method which is adapted to the problem. Moreover, the proposed methods are significantly faster
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Cadien, Adam Samuel. "Applications of the Wavelet Transform to B Mixing Analysis." 2008. http://hdl.handle.net/2429/868.
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Abstract
The neutral B mesons B0 and B0s can under go flavor changing oscillations due to interactions
by the weak force. Experiments which measure the frequency of these state transitions produce
extremely noisy results that are difficult to analyse. A method for extracting the frequency of B
mesons oscillations using the continuous wavelet transform is developed here.
In this paper the physics of B meson mixing is related, leading to the derivation of a function
describing the expected amount of mixing present in B0 and B0s meson decays. This result is then used to develop a new method for analysing the underlying frequency of oscillation in
B mixing. An introduction to wavelet theory is provided in addition to details on interpreting
daughter wavelet coefficient diagrams. Finally, the effectiveness of the analysis technique produced,
referred to as the Template Fitting Method, is investigated through an application to
data generated using Monte Carlo methods.
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Wang, Shiu Man, and 王秀滿. "Clinical evaluation of amphotericin B mixing with 10% fat." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/94567262284242446256.
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碩士國立成功大學
臨床藥學研究所
85
BACKGROUND： Amphotericin B (AmB) is the drug of choice for the treatment of several systemic fungal infections and in the management of neutropenic patients with persistent fever despite broad-spectrum antibiotics administration. Unfortunately its clinical use was severely limited bytwo major adverse reactions, fever with chills and renal dysfunction.In order to reduce the toxicity of AmB, several liposomal formulations ofAmB have been developed and proved to be effective. And the use of AmB mixing with Intralipid also showed a significant reduction in infusion- related toxicity and renal dysfunction. However, the methods of preparingthe mixtures and the administration regimens varied among literature, and the physicochemical stability of such formulations is still controversial. Here we undertaken a prospective observation study to evaluate the clinicaltolerance of AmB mixing with 10% fat emulsion and conventional AmB.The stability of the admixture of AmB and 10% or 20% fat emulsions was alsoinvestigated.METHODS：(1) A prospective clinical observation study was carried out by recording the use of AmB and its adverse reactions. To monitor the blood concentration of AmB, blood samples were withdrawn before and after the drug infusion on the seventh day of AmB treatment. (2) Admixtures of AmB 0.05, 0.1, 0.25 mg/mL were prepared by adding AmB solutions to 10% or 20% fat emulsions. After gentle shaking, a simulated 24-h continuos infusion of the mixtures which exposed to light was started at room temperature. Samples were collected hourly and the original, 2nd-, 4th-, 8th-, 12th-, 16th-, 20th-, 24th- hour and the residual collections immediately frozen at －20℃ until analyzed by high-performance liquid chromatography.RESULTS ：In the prospective clinical observation study, 35 patients treated for malignancies received either AmB in 5% dextrose (AmB-D5W, 0.78 mg/kg/d, 12.7 days, n=19) or AmB mixed with 10% fat emulsion (AmB-FE, 0.85 mg/kg/d, 14.1 days, n=16). AmB infusion induced fever in 9 patients in the AmB-D5W group and in 5 patients in the AmB-FE group. Chills associated with AmB occurred in 5 patients in the AmB-D5W group and 4 patients in the AmB-FE group. These were not significantly different between groups. Twenty-nine patients were eligible for evaluation of nephrotoxicity of AmB-D5W and AmB-FE after excluding patients with serum creatinine concentration above 1.5 mg/dL. Mean daily dose of AmB was 0.81(0.21 mg/kg in the AmB-D5W group and 0.86(0.21 mg/kg in the AmB-FE group. And mean duration of AmB-D5 W and AmB-FE received were 15.8(10.3, 16.7(9.1 days, respectively. Renal dysfunction was not significant different in 2 of 19 patients in the AmB-D5W group and 3 of 10 patients in the AmB-FE group. Serum AmB concentrations following AmB-D5W or AmB-FE administration ranged between 0.6-4.5 (g/mL, which were similar to the reported data. AmB concentrations in the fat emulsion preparations remained unchanged during infusion, indicating that AmB is stable in 10% and 20% fat emulsions for at least 24 hours at room temperature exposed to light. CONCLUSION：AmB was stable in fat emulsions and the adverse reactions were not different between AmB-10% fat emulsion and conventional AmB-D5W in our study. Since the currently available data about the use the AmB-Intralipid is limiting, the preparation of AmB with fat emulsion is not recommended as an alternative to conventional AmB.
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Song, Zhongzhi. "Monte Carlo studies for parameterization of B-mixing with dilepton events." Thesis, 2005. http://hdl.handle.net/2429/16706.
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In this thesis, we report on a Monte Carlo (MC) study of the parameterization
of probability distribution functions (PDFs) for neutral B mixing using dilepton
events. T(45) decays are generated and those with at least 2 leptons in final
state are used in this study. By choosing appropriate functions, a parameterization
of the B meson decay time difference Δt is obtained by studying the B
lifetime and the neutral B mixing frequency dependence of the dilepton events
using an event re-weighting technique. Our results, combined with Monte Carlo
studies of detector resolutions, can be used to obtain more precise measurements
of the B mixing frequency and B lifetimes from experimental data.Science, Faculty of
Physics and Astronomy, Department of
Graduate
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Wittlin, Jodi L. "A measurement of the time dependence of B(d) meson -- anti-B(d) meson mixing with kaon tagging." 2001. https://scholarworks.umass.edu/dissertations/AAI3027272.
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The time dependence of Bd - Bd mixing has been measured in b b events containing one or more kaons at the SLD experiment at the Stanford Linear Accelerator Center. A simultaneous measurement of the “right sign production fraction” of kaons from B d decays has also been made. The initial state B hadron flavor was determined using the large forward-backward asymetry provided by the polarized electron beam of the SLC in combination with a jet charge technique and information from the opposite hemisphere. From a sample of 400,000 Z0 events collected by the SLD experiment at SLC from 1996 to 1998, the kaon right sign production fraction has been measured to be 0.797 ± 0.022 and the mass difference between the two Bd eigenstates has been measured to be Δ md = 0.503 ± 0.028 ± 0.020 ps−1 .
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Evans, Richard. "Determination of the neutral B meson and neutral B(s) meson mixing matrix elements in 2+1 lattice QCD /." 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3337771.
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Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2008.Source: Dissertation Abstracts International, Volume: 69-11, Section: B, page: 6876. Adviser: Aida X. El-Khadra. Includes bibliographical references (leaves 122-124) Available on microfilm from Pro Quest Information and Learning.
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Zheng, Yangheng. "Measurement of B⁰B̄⁰-mixing and studies of the feasibility of measuring CP violation in B [to] D* [pi] decays." 2002. http://wwwlib.umi.com/dissertations/fullcit/3045448.
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Lin, Shi Chi, and 林士棊. "Development of Mixing Liquid TEM Holder for In-situ Observing of Self-assembling Co-polymer (PS-b-PDMS)." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/98645939403583146426.
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碩士國立清華大學
工程與系統科學系
104
Advanced techniques with in-situ liquid holder combined with wet cell chips in electron microscopic provide a new territory for us to explore and discover the identifiable scientific issue. The purpose of this research is to develop a mixing liquid holder for TEM with the combination of self-designed flow chips and SAW cells. The results can be shown in four parts. (1) Observed the mixing process of two different color fluorescent polystyrene beads and then calculate the mixing ratio of the two particles to get the ideal flow rate of the two liquid channels. (2) Observed the precipitation of calcium carbonate by injecting calcareous water and sodium bicarbonate liquid at the same time to ensure the usable of the mixing liquid holder. (3) In-situ observing phase transformation of polystyrene-block-polydimethylsiloxane (PS-b-PDMS) treated with toluene solvent vapor annealing process. (4) Developed heating and liquid holder and applied to PS-b-PDMS. These results show that self-designed mixing liquid holder with the combination of self-designed flow chips successfully observe the chemical precipitation of calcium carbonate and phase transformation of PS-b-PDMS. This holder is the linking of in-situ observing technique and the advance material research.
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Volk, Alexei [Verfasser]. "Measurement of the partial branching fraction for inclusive semileptonic B meson decays to light hadrons B→Xulv and an improved determination of the quark mixing matrix element Vub / von Alexei Volk." 2009. http://d-nb.info/100774944X/34.
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Banaszak, Magdalena. "Differentiation regimes in the Central Andean magma systems: case studies of Taapaca and Parinacota volcanoes, Northern Chile." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-991E-B.
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