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All hadronic B decay trigger with the CDF silicon vertex tracker

Description: Silicon Vertex tracks are of fundamental importance for reconstructing B meson decays at a hadron collider. The upgraded CDF detector will deploy an online Silicon Vertex Tracker in the level 2 trigger. We have studied how this new device exploits the Tevatron large B meson production to select hadronic B decays fundamental for measuring CP violation and B{sub s} mixing.
Date: October 19, 1999
Creator: Donati, Simone
Partner: UNT Libraries Government Documents Department

Amplitude Analysis of the Charmless Decays of Charged B Mesons to the Final States K+- Pi-+ Pi+- Using the BaBar Detector

Description: Results of an amplitude analysis of the B{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +} Dalitz plot are presented. The analysis uses a data sample with an integrated luminosity of 210.6 fb{sup -1}, recorded by the BABAR detector at the PEP-II asymmetric B Factory. This sample corresponds to 231.8 million B{bar B} pairs. Branching fractions and 90% confidence level upper limits are calculated, averaged over charge conjugate states (B). For those modes that have significant branching fraction measurements CP violating charge asymmetry measurements are also presented (A{sub CP}). The results from the nominal fit are summarized.
Date: September 18, 2006
Creator: Latham, Thomas Edward & U., /Bristol
Partner: UNT Libraries Government Documents Department

Amplitude Analysis of the Decay B0->K+pi-pi0

Description: We report an updated amplitude analysis of the charmless hadronic decays of neutral B mesons to K{sup +} {pi}{sup -}{pi}{sup 0}. With a sample of 454 million {Upsilon}(4S) {yields} B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, we measure the magnitudes and phases of the intermediate resonant and nonresonant amplitudes for B{sup 0} and B{sup 0} decays and determine the corresponding CP-averaged fit fractions and charge asymmetries.
Date: September 3, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department

Analysis of B -> omega lv Decays with BaBar (SULI)

Description: 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 {yields} wlv, which can be used to determine the Cabbibo-Kobayashi-Maskawa matrix element V{sub ub}. Using simulated event samples, this study focuses on determining criteria on variables for selection of B {yields} wlv signal and suppression of background from other types of B{bar B} 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 B{bar B} events recorded by BaBar in e{sup +}e{sup -} collisions at the {Upsilon}(4S) resonance, we obtain a yield of 115 {+-} 19 B {yields} wlv decays.
Date: December 15, 2005
Creator: Chu, Yi-Wen; /MIT; Littlejohn, B.; /Unlisted; Dingfelder, J. & /SLAC
Partner: UNT Libraries Government Documents Department

Analysis of Bs flavor oscillations at CDF

Description: The search for and study of flavor oscillations in the neutral B{sub s}B{sub s} meson system is an experimentally challenging task. It constitutes a flagship analysis of the Tevatron physics program. In this dissertation, they develop an analysis of the time-dependent B{sub s} flavor oscillations using data collected with the CDF detector. The data samples are formed of both fully and partially reconstructed B meson decays: B{sub s} {yields} D{sub s}{pi}({pi}{pi}) and B{sub s} {yields} D{sub s}lv. A likelihood fitting framework is implemented and appropriate models and techniques developed for describing the mass, proper decay time, and flavor tagging characteristics of the data samples. The analysis is extended to samples of B{sup +} and B{sup 0} mesons, which are further used for algorithm calibration and method validation. The B mesons lifetimes are extracted. The measurement of the B{sup 0} oscillation frequency yields {Delta}m{sub d} = 0.522 {+-} 0.017 ps{sup -1}. The search for B{sub s} oscillations is performed using an amplitude method based on a frequency scanning procedure. Applying a combination of lepton and jet charge flavor tagging algorithms, with a total tagging power {epsilon}'D{sup 2} of 1.6%, to a data sample of 355 pb{sup -1}, a sensitivity of 13.0 ps{sup -1} is achieved. They develop a preliminary same side kaon tagging algorithm, which is found to provide a superior tagging power of about 4.0% for the B{sub s} meson species. A study of the dilution systematic uncertainties is not reported. From its application as is to the B{sub s} samples the sensitivity is significantly increased to about 18 ps{sup -1} and a hint of a signal is seen at about 175. ps{sup -1}. They demonstrate that the extension of the analysis to the increasing data samples with the inclusion of the same side tagging algorithm is capable of providing ...
Date: September 1, 2006
Creator: Leonardo, Nuno T. & /MIT
Partner: UNT Libraries Government Documents Department

D and B meson spectroscopy, new states, baryons at the Tevatron

Description: We review recent results in heavy quark hadron spectroscopy at the Tevatron. With increasing data samples, the Tevatron experiments start to uncover information on the spectroscopy of b-hadrons. Most important are the first observations of the narrow B**{sub s}{sup 0} as well as {Sigma}{sub b}{sup {+-}}, {Sigma}*{sub b}{sup {+-}} and {Xi}{sub b}{sup -} baryons. In addition we present updated results on the narrow B**{sup 0} and B{sub c} mesons.
Date: December 1, 2007
Creator: Kreps, Michal & U., /Karlsruhe
Partner: UNT Libraries Government Documents Department

Apiary B Factory lattice design

Description: The Apiary B Factory is a proposed high-intensity electron-positron collider. This paper will present the lattice design for this facility, which envisions two rings with unequal energies in the PEP tunnel. The design has many interesting optical and geometrical features due to the needs to conform to the existing tunnel, and to achieve the necessary emittances, damping times and vacuum. Existing hardware is used to a maximum extent. 8 figs. 1 tab.
Date: April 1, 1991
Creator: Donald, M.H.R. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)) & Garren, A.A. (Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department

Apiary B-Factory separation scheme

Description: A magnetic beam-separation scheme for an asymmetric-energy B-Factory based on the SLAC electron-positron collider PEP is described that has the following properties: the beams collide head-on and are separated magnetically with sufficient clearance at the parasitic crossing points and at the septum, the magnets have large beam-stay-clear apertures, synchrotron radiation produces low detector backgrounds and acceptable heat loads, and the peak {beta}-function values and contributions to the chromaticities in the IR quadrupoles are moderate. 8 figs., 2 tabs.
Date: April 1, 1991
Creator: Garren, A. (Lawrence Berkeley Lab., CA (USA)) & Sullivan, M. (Stanford Linear Accelerator Center, Menlo Park, CA (USA))
Partner: UNT Libraries Government Documents Department

Application of heavy-light methods to B meson physics

Description: The heavy-light method is applied to the study of the B meson spectrum, the pseudoscalar decay constant f{sub B}, the mixing (B) parameter, and exclusive semileptonic B meson decays. Preliminary results are discussed for f{sub B} and the B parameter at {beta} = 5.7 and {kappa} = 0.165 on a 12{sup 3} {times} 24 lattice and at {beta} = 5.9 and {kappa} = 0.158 on a 16{sup 3} {times} 32 lattice. 9 refs., 2 figs., 2 tabs.
Date: December 29, 1989
Creator: Eichten, E.; Hockney, G. & Thacker, H.B.
Partner: UNT Libraries Government Documents Department

Application of HQET to B {r_arrow} K{sup *} transitions

Description: The authors examine the measured rates for the decays D {r_arrow} K{sup *}l{nu}, B {r_arrow} K{sup *}{psi}{prime} and B {r_arrow} K{sup *}{gamma} in a number of scenarios, in the framework of the heavy quark effective theory. They attempt to find a scenario in which all of these decays are described by a single set of form factors. Once such a scenario is found, they make predictions for the rare decays B {r_arrow} K{sup *}l{sup +}l{sup {minus}}. While they find that many scenarios can provide adequate descriptions of all the data, somewhat surprisingly, they observe that two popular choices of form factors, namely monopolar forms and exponential forms, exhibit some shortcomings, especially when confronted with polarization observables. They predict Br({anti B}{sup 0} {r_arrow} {anti K}{sup 0}{mu}{sup +}{mu}{sup {minus}}) = 6.4 {+-} 1.0 x 10{sup {minus}7} and Br({anti B}{sup 0} {r_arrow} {anti K}{sup *0}{mu}{sup +}{mu}{sup {minus}}) = 3.8 {+-} 1.3 x 10{sup {minus}6}. They also make predictions for polarization observables in these decays.
Date: October 1, 1995
Creator: Roberts, W. & Ledroit, F.
Partner: UNT Libraries Government Documents Department

Aspects of B physics

Description: Various aspects of weak decays are commented on. Probing of the standard model and of phenomena beyond the standard model are discussed, followed by a theoretical view of B mesons and some experimental observations on B mesons. The point is made that any data on B decay would be interesting in that it would provide powerful new constraints in analyses of the standard model and extensions thereof. (LEW)
Date: October 14, 1987
Creator: Gaillard, M.K.
Partner: UNT Libraries Government Documents Department

An asymmetric B factory based on PEP

Description: In this report we describe a design for a high-luminosity Asymmetric B Factory to be built in the PEP tunnel on the SLAC site. This proposal, a collaborative effort SLAC, LBL, and LLNL, is the culmination of more than two years of effort aimed at the design and construction of an asymmetric e{sup +}e{sup {minus}} collider capable of achieving a luminosity of L = 3 {times} 10{sup 33} cm{sup {minus}2} s{sup {minus}1}. The configuration adopted utilizes two storage rings, and electron ring operating at 9 GeV and a positron ring at 3.1 GeV, each with a circumference of 2200 m. The high-energy ring is an upgrade of the PEP storage ring at SLAC; all PEP magnets and most power supplies will be reused. The upgrade consists primarily of replacing the PEP vacuum chamber and RF system with newly designed versions optimized for the high-current environment of the B Factory. The low-energy ring will be newly constructed and will be situated atop the high-energy ring in the PEP tunnel. Utilities already installed in the PEP tunnel are largely sufficient to operate the two B Factory storage rings.
Date: February 1, 1991
Partner: UNT Libraries Government Documents Department

An Asymmetric B Factory based on PEP

Description: An Asymmetric B Factory to be installed in the PEP tunnel has been under study at SLAC, LBL and LLNL for several years. A mature design for a 9 GeV {times} GeV electron-positron collider with a design luminosity of 3 {times} 10{sup 33} cm{sup {minus}2}s{sup {minus}1} is presented. Solutions new exist for all the technical problems, including issues rlated high currents (e.g. beam instabilities, feedback systems, vacuum chamber design, lifetime degradation and radiation power dissipation in the interaction region) and those related to the related to the different energies of the beams (e.g. beam separation, beam -- beam interaction and detector requirements). The status of the design, including prototype development will be discussed.
Date: May 1, 1991
Creator: Hutton, A. & Zisman, M. S.
Partner: UNT Libraries Government Documents Department

An asymmetric B Factory based on PEP

Description: The study of rare and CP-violating B meson decays is well suited to a high-luminosity e{sup +} e{sup {minus}} collider. For studying certain decay processes there are also substantial benefits associated with asymmetric beam energies, which give a moving center of mass for the B mesons. We describe a design for a 9 GeV {times} 3.1 GeV B Factory in the PEP tunnel that would operate initially at a luminosity of 3 {times} 10{sup 33} cm{sup {minus}2}s{sup {minus}1}. Technical problems include issues related to high currents (e.g., beam instabilities, feedback systems, lifetime degradation and detector radiation power dissipation) and those related to the hetero-energetic beams (e.g., beam separation, beam-beam interaction and detector requirements). Issues requiring R D effort are identified. 8 refs., 2 figs., 2 tabs.
Date: June 1, 1990
Creator: Hutton, A. & Zisman, M. S.
Partner: UNT Libraries Government Documents Department

An asymmetric B-meson factory at PEP

Description: A preliminary design for a B-factory has been made using asymmetric collisions between positrons in the PEP storage ring and electrons in a new, log-energy ring. The design utilizes small-aperture, permanent-magnet quadrupoles close to the interaction point (IP). Optimization of optical and beam parameters at the IP will be discussed, as well as the lattice design of the interaction region and of the rings. 7 refs., 3 figs., 2 tabs.
Date: March 1, 1989
Creator: Garren, A.; Chattopadhyay, S.; Chin, Y.; Oddone, P.; Zisman, M.S.; Donald, M. et al.
Partner: UNT Libraries Government Documents Department

Average and individual B hadron lifetimes at CDF

Description: Bottom hadron lifetime measurements have been performed using B {yields} J/{psi} {yields} {mu}+{mu}{sup {minus}}X dacays recorded with the collider Detector at Fermilab (CDF) during the first half of the 1992--1993 Tevatron collider run. These decays have been reconstructed in a silicon vertex detector. Using 5344 {plus_minus} 73 inclusive J/{psi} events, the average lifetime of all bottom hadrons produced in 1.8 TeV p{bar p} collisions and decaying into a J/{psi} events, the average lifetime of all bottom hadrons produced in 1.8 TeV p{bar p} collisions and decaying into a J/{psi} is found to be 1.46 {plus_minus} 0.06(stat) {plus_minus}0.06(sys)ps. The charged and neutral B meson lifetimes have been measured separately using 75 {plus_minus}10 (charged) and 61{plus_minus}9 (neutral) fully reconstructed decays; preliminary results are {tau}{sup {plus_minus}} = 1.63 {plus_minus} 0.21(stat) {plus_minus} 0.16(sys) {plus_minus} 0. 10(sys) ps, yielding a lifetime ratio of {tau}{sup {plus_minus}}/{tau}{sup 0} = 1.06{plus_minus} 0.20(stat){plus_minus}0.12(sys).
Date: September 1, 1993
Creator: Schneider, O. & Collaboration, CDF
Partner: UNT Libraries Government Documents Department

B^0 to \pi^+ \pi^- \pi^0Time Dependent Dalitz Analysis at BaBar

Description: The author presents here results of a time-dependent analysis of the Dalitz structure of neutral B meson decays to {pi}{sup +}{pi}{sup -}{pi}{sup 0} from a dataset of 346 million B{bar B} pairs collected at the {Upsilon}(4S) center of mass energy by the BaBar detector at the SLAC PEP-II e{sup +}e{sup -} accelerator. No significant CP violation effects are observed and 68% confidence interval is derived on the weak angle {alpha} to be [75,152].
Date: April 6, 2007
Creator: Cavoto, Gianluca
Partner: UNT Libraries Government Documents Department

$B^0_s$ and $B^0$ Mixing in the Standard Model and Beyond: A Progress Report

Description: We give a progress report on the calculation of B meson mixing matrix elements, focusing on contributions that could arise beyond the Standard Model. The calculation uses asqtad (light quark) and Fermilab (heavy quark) valence actions and MILC ensembles with 2+1 flavors of asqtad sea quarks. We report preliminary B{sub s}{sup 0} fit results, at a lattice spacing of 0.12 fm, for the SUSY basis of effective four-quark mixing operators and include an estimate for the final error budget.
Date: November 1, 2010
Creator: Bouchard, C.; /Illinois U., Urbana /Fermilab; El-Khadra, A.X.; /Illinois U., Urbana; Freeland, E.D.; /Illinois U., Urbana /Washington U., St. Louis et al.
Partner: UNT Libraries Government Documents Department

B and D Meson Decay Constants

Description: We present an update of our calculations of the decay constants of the D, D{sub s}, B, and B{sub s} mesons in unquenched 2+1 flavor QCD. We use the MILC library of improved staggered gauge ensembles at lattice spacings 0.09, 0.12, and 0.15 fm, clover heavy quarks with the Fermilab normalizations, and improved staggered light valence quarks.
Date: April 1, 2009
Creator: Bernard, C.; DeTar, C.; Di Pierro, M.; El-Khadra, A. X.; Evans, R. T.; Freeland, Elizabeth Dawn et al.
Partner: UNT Libraries Government Documents Department

B and D meson decay constants from 2+1 flavor improved staggered simulations

Description: We give an update on simulation results for the decay constants f{sub B}; f{sub B{sub s}}, f{sub D} and f{sub D{sub s}}. These decay constants are important for precision tests of the standard model, in particular entering as inputs to the global CKM unitarity triangle fit. The results presented here make use of the MILC (2+1)-flavor asqtad ensembles, with heavy quarks incorporated using the clover action with the Fermilab method. Partially quenched, staggered chiral perturbation theory is used to extract the decay constants at the physical point. In addition, we give error projections for a new analysis in progress, based on an extended data set.
Date: December 1, 2011
Creator: Neil, E.T.; Bailey, Jon A.; Bazavov, A.; Bernard, C.; Bouchard, C.M.; DeTar, C. et al.
Partner: UNT Libraries Government Documents Department

B and D mesons in lattice QCD

Description: Computational and theoretical developments in lattice QCD calculations of B and D mesons are surveyed. Several topical examples are given: new ideas for calculating the HQET parameters {bar {Lambda}} and {lambda}{sub 1}; form factors needed to determine {vert_bar}V{sub cb}{vert_bar} and {vert_bar}V{sub ub}{vert_bar}; bag parameters for the mass differences of the B mesons; and decay constants. Prospects for removing the quenched approximation are discussed.
Date: October 17, 2000
Creator: Kronfeld, Andreas S.
Partner: UNT Libraries Government Documents Department