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Heavy flavor physics at CDF II

Description: Tevatron experiments will soon begin Run II data taking with an aggressive B physics program. The B physics reach of the CDF and D0 experiments already seems competitive and complementary to that of B factories. We report on the future plans for B physics and CP violation measurements at the Tevatron.
Date: July 12, 2001
Creator: Cerri, A.
Partner: UNT Libraries Government Documents Department

CP violation and B mixing in CDF-II

Description: In March 2001, the Tevatron at Fermilab will start a new run at {radical}s = 2.0 TeV, delivering an integrated luminosity of 2 fb{sup {minus}1} in the first two years and more than 15 fb{sup {minus}1} in the following years, before the start of LHC at CERN. CDF has been upgraded to cope with the new physics program. The authors present here the prospects for measuring B mixing and CP violation during the upcoming run.
Date: September 12, 2000
Creator: Ruiz, Alberto
Partner: UNT Libraries Government Documents Department

B Physics in CDF

Description: The upgraded CDF detector is now collecting data with the aim of integrating 2 fb{sup -1} by year 2006. The pursued B physics program is very appealing. CDF will provide measurements of various CP violating and B mixing parameters which both complement and extend B-factories measurements. In addition there is a variety of spectroscopy measurements on B{sub s} and heavier B hadrons which are currently accessible only at the Tevatron. In this talk we give a description of the new CDF tools available for B physics, we discuss the preliminary results obtained with the first 70 pb{sup -1} of data, and we highlight Run II B physics prospects.
Date: August 12, 2003
Creator: Fiori, Irene
Partner: UNT Libraries Government Documents Department

Problems at the interface between heavy flavor physics, QCD and hadron spectroscopy.

Description: The following subjects are discussed in this report: (1) Pentaquark--why it is important and how new technologies (vertex detectors) suggest drastically different approaches form the search used by Ashery et al.; (2) problems in B decays with implications for heavy quark decays to excited light quark states like the Al; (3) problems in B and D decays to final states including {eta} and {eta}{prime} indicating that standard quark mixing might not hold; (4) possible contributions of hybrid quarkonium states to B decays; (5) heavy flavor decays to {omega}{tau} which disagree with conventional expectations; and (6) possible new spin effects in {Lambda}{sub b} decay and the effect on the lifetime difference between the {Lambda}{sub b} and B mesons.
Date: December 12, 1997
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department

Measurement and Interpretation of Moments of the Combined Hadronic Mass and Energy Spectrum in Inclusive Semileptonic B-Meson Decays

Description: This thesis presents first measurements of moments of the hadronic n{sub X}{sup 2} distribution measured in inclusive semileptonic decays of B mesons to final states containing a charm quark, B {yields} X{sub c}{ell}{nu}. The variable n{sub X}{sup 2} is a combination of the invariant mass of the charmed meson m{sub X}, its energy in the B-meson rest-frame E{sub X;BRF}, and a constant {tilde {Lambda}} = 0.65 GeV, n{sub X}{sup 2} = m{sub X}{sup 2}c{sup 4}-2{tilde {Lambda}}E{sub X,BRF} + {tilde {Lambda}}{sup 2}. The moments <n{sub X}{sup k}> with k = 2,4,6 are measured as proposed by theory to constrain assumptions made in the theoretical description of inclusive observables in semileptonic B-meson decays. This description uses Heavy Quark Expansion (HQE), an effective QCD combined with an Operator Product Expansion. The measurement is based on a sample of 231.6 million e{sup +}e{sup -} {yields} {Upsilon}(4S) {yields} B{bar B} events recorded with the BABAR experiment at the PEP-II e{sup +}e{sup -}-storage rings at SLAC. We reconstruct the semileptonic decay by identifying a charged lepton in events tagged by a fully reconstructed hadronic decay of the second B meson. Correction procedures are derived from Monte Carlo simulations to ensure an unbiased measurement of the moments of the n{sub X}{sup 2} distribution. All moments are measured requiring minimum lepton momenta between 0.8 GeV/c and 1.9 GeV/c in the rest frame of the B meson. Performing a simultaneous fit to the measured moments <n{sub X}{sup k}> up to order k = 6 combined with other measurements of moments of the lepton-energy spectrum in decays B {yields} X{sub c}{ell}{nu} and moments of the photon-energy spectrum in decays B {yields} X{sub s}{gamma}, we determine the quark-mixing parameter |V{sub cb}|, the bottom and charm quark masses, the semileptonic branching fraction {Beta}(B {yields} X{sub c}{ell}{nu}), and four non-perturbative heavy quark parameters. ...
Date: August 12, 2011
Creator: Klose, Verena
Partner: UNT Libraries Government Documents Department

A Measurement of the Semileptonic Branching Fraction of the B_s Meson

Description: We report a measurement of the inclusive semileptonic branching fraction of the B{sub s} meson using data collected with the BABAR detector in the center-of-mass energy region above the {gamma}(4S) resonance. We use the inclusive yield of {phi} mesons and the {phi} yield in association with a high-momentum lepton to perform a simultaneous measurement of the semileptonic branching fraction and the production rate of B{sub s} mesons relative to all B mesons as a function of center-of-mass energy. The inclusive semileptonic branching fraction of the B{sub s} meson is determined to be {Beta}(B{sub s} {yields} {ell}{nu}X) = 9.5{sub -2.0}{sup +2.5}(stat){sub -1.9}{sup +1.1}(syst)%, where {ell} indicates the average of e and {mu}.
Date: June 12, 2012
Creator: Lees, J.P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M. et al.
Partner: UNT Libraries Government Documents Department

Observation of the Decay B- --> Ds(*) K- l- nubar

Description: We report the observation of the decay B{sup -} {yields} D{sub s}{sup (*)+} K{sup -}{ell}{sup -}{bar {nu}}{sub {ell}} based on 342 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings at SLAC. A simultaneous fit to three D{sub s}{sup +} decay chains is performed to extract the signal yield from measurements of the squared missing mass in the B meson decay. We observe the decay B{sup -} {yields} D{sub s}{sup (*)+} K{sup -}{ell}{sup -}{bar {nu}}{sub {ell}} with a significance greater than five standard deviations (including systematic uncertainties) and measure its branching fraction to be {Beta}(B{sup -} {yields} D{sub s}{sup (*)+} K{sup -}{ell}{sup -}{bar {nu}}{sub {ell}}) = [6.13{sub -1.03}{sup +1.04}(stat.) {+-} 0.43(syst.) {+-} 0.51({Beta}(D{sub s}))] x 10{sup -4}, where the last error reflects the limited knowledge of the D{sub s} branching fractions.
Date: August 12, 2011
Creator: del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP et al.
Partner: UNT Libraries Government Documents Department

Measurement of Partial Branching Fractions of Inclusive Charmless B Meson Decays to K , K0, and pi

Description: The authors present measurements of partial branching fractions of B {yields} K{sup +}X, B {yields} K{sup 0} X, and B {yields} {pi}{sup +}X, where X denotes any accessible final state above the endpoint for B decays to charmed mesons, specifically for momenta of the candidate hadron greater than 2.34 (2.36) GeV for kaons (pions) in the B rest frame. These measurements are sensitive to potential new-phisics particles which could enter the b {yields} s(d) loop transitions. The analysis is performed on a data sample consisting of 383 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II e{sup +}e{sup -} asymmetric energy collider. The results are in agreement with standard model predictions and exclude large enhancements of the inclusive branching fraction due to sources of new physics.
Date: August 12, 2011
Creator: del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP et al.
Partner: UNT Libraries Government Documents Department

Measurement of Branching Fractions and Mass Spectra of B to K pi pi gamma

Description: The authors present a measurement of the partial branching fractions and mass spectra of the exclusive radiative penguin processes B {yields} K{pi}{pi}{gamma} in the range m{sub K{pi}{pi}} < 1.8 GeV/c{sup 2}. They reconstruct four final states: K{sup +}{pi}{sup -}{pi}{sup +}{gamma}, K{sup +}{pi}{sup -}{pi}{sup 0}{gamma}, K{sub S}{sup 0}{pi}{sup -}{pi}{sup +}{gamma}, and K{sub S}{sup 0}{pi}{sup +}{pi}{sup 0}{gamma}, where K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}. Using 232 million e{sup +}e{sup -} {yields} B{bar B} events recorded by the BABAR experiment at the PEP-II asymmetric-energy storage ring, they measure the branching fractions {Beta}(B{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +}{gamma}) = (2.95 {+-} 0.13(stat.) {+-} 0.20(syst)) x 10{sup -5}, {Beta}(B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}{gamma}) = (4.07 {+-} 0.22(stat.) {+-} 0.31(syst.)) x 10{sup -5}, {Beta}(B{sup 0} {yields} K{sup 0}{pi}{sup +}{pi}{sup -}{gamma}) = (1.85 {+-} 0.21(stat.) {+-} 0.12(syst.)) x 10{sup -5}, and {Beta}(B{sup +} {yields} K{sup 0}{pi}{sup +}{pi}{sup 0}{gamma}) = (4.56 {+-} 0.42(stat.) {+-} 0.31(syst.)) x 10{sup -5}.
Date: July 12, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department

Measurement of the Branching Fraction of B0 Meson Decay to a_1^+(1260) pi-

Description: We present a preliminary measurement of the branching fraction of the B meson decay B{sup 0} {yields} a{sub 1}{sup +}(1260){pi}{sup -}with a{sub 1}{sup +}(1260) {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -}. The data sample corresponds to 218 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation through the {Upsilon}(4S) resonance. We find the branching fraction (40.2 {+-} 3.9 {+-} 3.9) x 10{sup -6}, where the first error quoted is statistical and the second is systematic. The fitted values of the a{sub 1}(1260) parameters are m{sub a{sub 1}} = 1.22 {+-} 0.02 GeV/c{sup 2} and {Lambda}{sub a{sub 1}} = 0.423 {+-} 0.050 GeV/c{sup 2}.
Date: July 12, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department

Study of Inclusive And Exclusive B ---> X/U L Nu Decays And the Measurement of |V(Ub)| With the BaBar Detector

Description: We report studies of B {yields} X{sub u}{ell}{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 {yields} X{sub c}{ell}{nu} is reduced by making requirements on different variables: the electron energy E{sub l}, the momentum transfer q{sup 2}, and the hadronic mass m{sub X}. Using theoretical calculations we extrapolate to the total decay rate to determine the CKM matrix element |V{sub ub}|. In addition, we have measured the branching fraction for exclusive semileptonic decays, such as B {yields} {pi}({rho}, {omega}, {eta}, a{sub 0}){ell}{nu}. A high signal purity is achieved by selecting events in which a decay of the second B meson is either fully or partially reconstructed.
Date: October 12, 2005
Creator: del Re, D. & /UC, San Diego
Partner: UNT Libraries Government Documents Department

B Decays to Open And Hidden Charm at BaBar

Description: A wealth of new measurements of hadronic B decays to open charm and charmonium have been performed on the data sample collected by the BaBar experiment at the PEP-II e{sup +}e{sup -} B-factory. We report the first measurement of the rates for inclusive charm production separately for charged and neutral B mesons. Combining measurements of the decay rate of B{sup 0} {yields} D*{sub s}{sup +}D*{sup -} obtained with a partial reconstruction technique and the complete reconstruction of B{sup 0} {yields} D*{sub s}{sup +}D*{sup -} with D{sub s}{sup +} {yields} {phi}{pi}{sup +}, we obtain the most precise measurement of {Beta}(D{sub s}{sup +} {yields} {phi}{pi}{sup +}). We present an update of the measurements of the branching fractions of exclusive B decays to J/{psi}, {psi}(2S), {chi}{sub c1}, {chi}{sub c2} and a kaon or a K*. In addition, we show preliminary results on exclusive decay rates to final states with baryons, or newly-discovered particles, such as D*{sub sJ}(2317), D{sub sJ}(2460){sup +}, and the X(3872).
Date: October 12, 2005
Creator: Ricciardi, S. & /Royal Holloway, U. of London
Partner: UNT Libraries Government Documents Department

Rare B Decays at Babar

Description: The author presents some of the most recent BABAR measurements for rare B decays. These include rate asymmetries in the B decays to K{sup (*)}l{sup +}l{sup -} and K{sup +}{pi}{sup -} and branching fractions in the B decays to l{sup +}{nu}{sub l}, K{sub 1}(1270){sup +}{pi}{sup -} and K{sub 1}(1400){sup +}{pi}{sup -}. The author also reports a search for the B{sup +} decay to K{sub S}{sup 0}K{sub S}{sup 0}{pi}{sup +}.
Date: January 12, 2009
Creator: Palombo, Fernando & Collaboration, for the BABAR
Partner: UNT Libraries Government Documents Department