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Measurement of Decay Amplitudes of B to ccbar K* with an angular analysis, for ccbar=J/Psi, Psi2S and chic1

Description: We perform the first three-dimensional measurement of the amplitudes of B {yields} {psi}(2S)K* and B {yields} {chi}{sub c1}K* decays and update our previous measurement for B {yields} J/{psi} K*. We use a data sample collected with the BABAR detector at the PEP-II storage ring, representing 232 million produced B{bar B} pairs. The longitudinal polarization of decays to the 1{sup ++} {chi}{sub c1} meson together with a K* meson, is found to be larger than that for the decay to the 1{sup --} {Psi} mesons. No direct CP-violating charge asymmetry is observed.
Date: August 18, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of CP-Violating Asymmetries in B0 to (rho pi)0 using a Time-Dependent Dalitz Plot Analysis

Description: We report a measurement of CP-violating asymmetries in B{sup 0} {yields} ({rho}{pi}){sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 375 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 26 coefficients of the bilinear form-factor terms occurring in the time-dependent decay rate of the B{sup 0} meson. We derive the physically relevant quantities from these coefficients. In particular, we measure a constraint on the angle {alpha} of the Unitarity Triangle.
Date: March 6, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of CP-Violating Asymmetries in B0 to (rho pi)0 Using a Time-Dependent Dalitz Plot Analysis

Description: We report a measurement of CP-violating asymmetries in B{sup 0} {yields} ({rho}{pi}){sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 347 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 26 coefficients of the bilinear form factor terms occurring in the time-dependent decay rate of the B{sup 0} meson and derive the physically relevant quantities from these coefficients. In particular we find a three standard deviation evidence of direct CP-violation in the B{sup 0} {yields} {rho}{sup {+-}}{pi}{sup {-+}} decays, with systematic uncertainties included. We also achieve a constraint of the angle {alpha} of the Unitarity Triangle. All results presented are preliminary.
Date: September 26, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

A Measurement of CP-violation Parameters in B0B0barMixing using Partially Reconstructed D^{*-}l^+ nu_l Events at BaBar

Description: CP violation in B{sup 0}{bar B}{sup 0} mixing is characterized by the value of the parameter |q/p| being different from 1, and the Standard Model predicts this difference to be smaller than 10{sup -3}. We present a measurement of this parameter using a partial reconstruction of one of the B mesons in the semileptonic channel D*{sup -}{ell}{sup +}{nu}{sub {ell}}, where only the hard lepton and the soft pion from the D*{sup -} {yields} {bar D}{sup 0}{pi}{sup -} decay are reconstructed. The flavor of the other B is determined by means of lepton tagging. The determination of |q/p| is then performed with a fit to the proper time difference of the two B decays. We use a luminosity of 200.8 fb{sup -1}, collected at the {Upsilon}(4S) resonance by the BABAR detector at the PEP-II asymmetrical-energy e{sup +}e{sup -} collider, in the period 1999-2004. We obtain the preliminary result: |q/p| - 1 = (6.5 {+-} 3.4(stat.) {+-} 2.0(syst.)) {center_dot} 10{sup -3}.
Date: August 18, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of CP Violation Parameters with a Dalitz Plot Analysis of B+- to D(pi+pi-pi0)K+-

Description: We report the results of a CP violation analysis of the decay B{sup {+-}} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}}K{sup {+-}}, where D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} indicates a neutral D meson detected in the final state {pi}{sup +}{pi}{sup -}{pi}{sup 0}, excluding K{sub S}{sup 0}{pi}{sup 0}. The analysis makes use of 324 million e{sup +}e{sup -} {yields} B{bar B} events recorded by the BABAR experiment at the PEP-II e{sup +}e{sup -} storage ring. By analyzing the {pi}{sup +}{pi}{sup -}{pi}{sup 0} Dalitz plot distribution and the B{sup {+-}} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} K{sup {+-}} branching fraction and decay rate asymmetry, we calculate parameters related to the phase {gamma} of the CKM unitarity triangle. We also measure the magnitudes and phases of the components of the D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} decay amplitude.
Date: March 28, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of the B to pi l nu Branching Fraction and Determination of |Vub| with Tagged B Mesons

Description: We report a measurement of the B {yields} {pi}{ell}{nu} branching fraction based on 211 fb{sup -1} of data collected with the BABAR detector. We use samples of B{sup 0} and B{sup +} mesons tagged by a second B meson reconstructed in a semileptonic or hadronic decay, and combine the results assuming isospin symmetry to obtain {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}) = (1.33 {+-} 0.17{sub stat} {+-} 0.11{sub syst}) x 10{sup -4}. We determine the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub ub}| by combining the partial branching fractions measured in ranges of the momentum transfer squared and theoretical calculations of the form factor. Using a recent lattice QCD calculation, we find |{sub ub}| = (4.5 {+-} 0.5{sub stat} {+-} 0.3{sub syst} {sub -0.5}{sup +0.7}FF) x 10{sup -3}, where the last error is due to the normalization of the form factor.
Date: August 23, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of the B+- to rho pi0 Branching Fraction and Direct CP Asymmetry

Description: The authors present improved measurements of the branching fraction and CP asymmetry for the process B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0}. The data sample corresponding to 211 fb{sup -1} comprises 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. The yield and CP asymmetry are measured using an extended maximum likelihood fitting method. The branching fraction and Cp asymmetry are found to be {Beta}(B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0}) = [10.2 {+-} 1.4(stat) {+-} 0.9(syst)] x 10{sup -6} and {Alpha}{sub CP}(B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0}) = -0.01 {+-} 0.13(stat) {+-} 0.02(syst).
Date: January 25, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of the B to Xs gammaBranching Fraction and Photon Energy Spectrum usingthe Recoil Method

Description: We present a measurement of the branching fraction and photon energy spectrum for the decay B {yields} X{sub s}{gamma} using data from the BABAR experiment. The data sample corresponds to an integrated luminosity of 210 fb{sup -1}, from which approximately 680,000 B{bar B} events are tagged by a fully reconstructed hadronic decay of one of the B mesons. In the decay of the second B meson, an isolated high-energy photon is identified. We measure {Beta}(B {yields} X{sub s}{gamma}) = (3.66 {+-} 0.85{sub stat} {+-} 0.60{sub syst}) x 10{sup -4} for photon energies E{sub {gamma}} above 1.9 GeV in the B rest frame. From the measured spectrum we calculate the first and second moments for different minimum photon energies, which are used to extract the heavy-quark parameters m{sub b} and {mu}{sub {pi}}{sup 2}. In addition, measurements of the direct CP asymmetry and isospin asymmetry are presented.
Date: December 4, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of the Time-dependent CP Asymmetry inB to D(*)_CP h0 Decays

Description: The authors report a measurement of the time-dependent CP-asymmetry parameters S and C in color-suppressed B{sup 0} {yields} D{sup (*)0}h{sup 0} decays, where h{sup 0} is a {pi}{sup 0}, {eta}, or {omega} meson, and the D{sup 0} decays to one of the CP eigenstates K{sup +}K{sup -}, K{sub S}{sup 0}{pi}{sup 0}, or K{sub S}{sup 0}{omega}. The data sample consists of 383 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B-factory at SLAC. The results are S = -0.56 {+-} 0.23 {+-} 0.05 and C = -0.23 {+-} 0.16 {+-} 0.04, where the first error is statistical and the second is systematic.
Date: March 14, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Improved Measurement of the CKM Angle gamma in B^-+ to D^(*) K^(*)-+Decays with a Dalitz Plot Analysis of D Decays to K_S^0 pi+ pi- and K_S^0 K+ K-

Description: We report on an improved measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub s}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub s}{sup 0}K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K8{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}. Using a sample of 383 million B{bar B} pairs collected by the BABAR detector, we measure {gamma} = (76 {+-} 22 {+-} 5{+-} 5){sup o} (mod 180{sup o}), where the first error is statistical, the second is the experimental systematic uncertainty and the third reflects the uncertainty on the description of the Dalitz plot distributions. The corresponding two standard deviation region is 29{sup o} < {gamma} < 122{sup o}. This result has a significance of direct CP violation ({gamma} {ne} 0) of 3.0 standard deviations.
Date: April 22, 2008
Creator: Aubert, : B.
Partner: UNT Libraries Government Documents Department

Improved Measurements of the Branching Fractions for B0 into pi+pi- and B0 into K+pi-, and a Search for B0 into K+K-

Description: The authors present measurements of the branching fractions for the charmless two-body decays B{sup 0} {yields} {pi}{sup +}{pi}{sup -} and B{sup 0} {yields} K{sup +}{pi}{sup -}, and a search for the decay B{sup 0} {yields} K{sup +}K{sup -}. They include the effects of final-state radiation from the daughter mesons for the first time, and quote branching fractions for the inclusive processes B{sup 0} {yields} h{sup +}h'{sup -}n{gamma}, where h and h' are pion or kaons. The maximum value of the sum of the energies of the n undetected photons, E{sub {gamma}}{sup max}, is mode-dependent. Using a data sample of approximately 227 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC.
Date: September 26, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of the Branching Fraction and Time-Dependent CP Asymmetry in the Decay B0 to D*+D*-Ks

Description: The authors study the decay B{sup 0} {yields} D*{sup +}D*{sup -} K{sub S}{sup 0} using (230 {+-} 2) x 10{sup 6} B{bar B} pairs collected by the BABAR detector at the PEP-II B factory. They measure a branching fraction {Beta}(B{sup 0} {yields} D*{sup +}D*{sup -} K{sub S}{sup 0}) = (4.4 {+-} 0.4 {+-} 0.7) x 10{sup -3} and find evidence for the decay B{sup 0} {yields} D*{sup -} D{sub s1}{sup +}(2536) with a statistical significance of 4.6 {sigma}. A time-dependent CP asymmetry analysis is also performed to study the possible resonant contributions to B{sup 0} {yields} D*{sup +}D*{sup -} K{sub S}{sup 0} and the sign of cos2{beta}. Their measurement indicates that there is a sizable resonant contribution to the decay B{sup 0} {yields} D*{sup +} D*{sup -} K{sub S}{sup 0} from a unknown D{sub s1}{sup +} state with large width, and that cos2{beta} is positive at the 94% confidence level under certain theoretical assumptions.
Date: September 26, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of the Branching Fraction, Polarization, and CP Asymmetries in B0->rho0rho0 Decay, and Implications for the CKM Angle alpha

Description: We study B{sup 0} {yields} {rho}{sup 0}{rho}{sup 0} decays in a sample of 465 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider located at the Stanford Linear Accelerator Center (SLAC). We measure the branching fraction {Beta} = (0.92 {+-} 0.32 {+-} 0.14) x 10{sup -6} and longitudinal polarization fraction f{sub L} = 0.75{sub -0.14}{sup +0.11} {+-} 0.04, where the first uncertainty is statistical and the second is systematic. The evidence for the B{sup 0} {yields} {rho}{sup 0}{rho}{sup 0} signal has a significance of 3.1 standard deviations, including systematic uncertainties. We investigate the proper-time dependence of the longitudinal component in the decay and measure the CP-violating coefficients S{sub L}{sup 00} = (0.3 {+-} 0.7 {+-} 0.2) and C{sub L}{sup 00} = (0.2 {+-} 0.8 {+-} 0.3). They study the implication of these results for the unitarity triangle angle {alpha}.
Date: September 10, 2008
Creator: Aubert, B
Partner: UNT Libraries Government Documents Department

A Measurement of the Branching Fractions ofexclusive Bbar to D(*)(pi)lnu Decays in Events with a Fully Reconstructed BMeson

Description: The authors report a measurement of the branching fractions for {bar B} {yields} D{sup (*)}{pi}{ell}{sup -}{bar {nu}}{sub {ell}} decays based on 341.1 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. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. The obtain {Beta}(B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = (2.33 {+-} 0.09{sub stat.} {+-} 0.09{sub syst.})%, {Beta}(B{sup -} {yields} D*{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = 5.83 {+-} 0.15{sub stat.} {+-} 0.30{sub syst.}%, {Beta}({bar B}{sup 0} {yields} D{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = (2.21 {+-} 0.11{sub stat.} {+-} 0.12{sub syst.})% {Beta}({bar B}{sup 0} {yields} D*{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = 5.49 {+-} 0.16{sub stat.} {+-} 0.25{sub syst.}%, {Beta}(B{sup -} {yields} D{sup +}{pi}{sup -}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.42 {+-} 0.06{sub stat.} {+-} 0.03{sub syst.})%, {Beta}(B{sup -} {yields} D*{sup +} {pi}{sup -}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.59 {+-} 0.05{sub stat.} {+-} 0.04{sub syst.})%, {Beta}({bar B}{sup 0} {yields} D{sup 0}{pi}{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.43 {+-} 0.08{sub stat.} {+-} 0.03{sub syst.})% and {Beta}({bar B}{sup 0} {yields} D*{sup 0} {pi}{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.48 {+-} 0.08{sub stat.} {+-} 0.04{sub syst.})%.
Date: January 8, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurements of the Branching Fraction and Time-Dependent CP Asymmetries of B0 to J/Psi pi0 Decays.

Description: The authors present measurements of the branching fraction and time-dependent CP asymmetries in B{sup 0} {yields} J/{psi} {pi}{sup 0} decays based on (231.8 {+-} 2.6) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC during the years 1999-2004. We obtain a branching fraction {Beta}(B{sup 0} {yields} J/{psi}{pi}{sup 0}) = (1.94 {+-} 0.22 (stat) {+-} 0.17 (syst)) x 10{sup -5}. They also measure the CP asymmetry parameters C = -0.21 {+-} 0.26 (stat) {+-} 0.09 (syst) and S = -0.68 {+-} 0.30 (stat) {+-} 0.04 (syst). All results presented in this paper are preliminary.
Date: August 4, 2005
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurements of the Decays B0->D0barppbar, B0->D*0ppbar, B0->D-ppbar\pi+, and B0->D*-ppbar\pi+

Description: The authors present measurements of branching fractions of B{sup 0} decays to multi-body final states containing protons, based on 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. They measure the branching fractions {Beta}(B{sup 0} {yields} {bar D}{sup 0} p{bar p}) = (1.13 {+-} 0.06 {+-} 0.08) x 10{sup -4} {Beta}(B{sup 0} {yields} {bar D}*{sup 0} p{bar p}) = (1.01 {+-} 0.10 {+-} 0.09) x 10{sup -4}, {Beta}(B{sup 0} {yields} D{sup -} p{bar p}{pi}{sup +}) = (3.38 {+-} 0.14 {+-} 0.29) x 10{sup -4}, and {Beta}(B{sup 0} {yields} D*{sup -} p{bar p}{pi}{sup +}) = (4.81 {+-} 0.22 {+-} 0.44) x 10{sup -4} where the first error is statistical and the second systematic. They present a search for the charmed pentaquark state, {Theta}{sub c}(3100) observed by H1 and put limits on the branching fraction {Beta}(B{sup 0} {yields} {Theta}{sub c}{bar p}{pi}{sup +}) x {Beta}({Theta}{sub c} {yields} D*{sup -}p) < 14 x 10{sup -6} and {Beta}(B{sup 0} {yields} {Theta}{sub c}{bar p}{pi}{sup +}) x {Beta}({Theta}{sub c} {yields} D{sup -}p) < 9 x 10{sup -6}. Upon investigation of the decay structure of the above four B{sup 0} decay modes, they see an enhancement at low p{bar p} mass and deviations from phase-space in the {bar D}{bar p} and {bar D}p invariant mass spectra.
Date: July 28, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of the Branching Fraction and Photon Energy Moments of B to Xs gamma and A_cp (B to X_{s+d} gamma)

Description: The photon spectrum in B {yields} X{sub s}{gamma} decay, where X{sub s} is any strange hadronic state, is studied using a data sample of 88.5 x 10{sup 6} e{sup +}e{sup -} {yields} {Upsilon}(4S) {yields} B{bar B} decays collected by the BABAR experiment at SLAC. The partial branching fraction, {Delta}{Beta}(B {yields} X{sub s}{gamma}) = (3.67 {+-} 0.29(stat.) {+-} 0.34(sys.) {+-} 0.29(model)) x 10{sup -4}, the first moment <E{sub {gamma}}> = 2.288 {+-} 0.025 {+-} 0.017 {+-} 0.015 GeV and the second moment <E{sub {gamma}}{sup 2}> = 0.0328 {+-} 0.0040 {+-} 0.0023 {+-} 0.0036 GeV{sup 2} are measured for the photon energy range 1.9 GeV < E{sub {gamma}} < 2.7 GeV. They are also measured for narrower E{sub {gamma}} ranges. The moments are then fit to recent theoretical calculations to extract the Heavy Quark Expansion parameters, m{sub b} and {mu}{sub {pi}}{sup 2}, and to extrapolate the partial branching fraction to E{sub {gamma}} > 1.6 GeV. In addition, the direct CP asymmetry A{sub CP}(B {yields} X{sub s+d{gamma}}) is measured to be -0.110 {+-} 0.115(stat.) {+-} 0.017(sys.).
Date: September 26, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Determinations of |V_{ub}| from Inclusive Semileptonic B Decays with Reduced Model Dependence

Description: We report two novel determinations of |V{sub ub}| with reduced model dependence, based on measurements of the mass distribution of the hadronic system in semileptonic B decays. Events are selected by fully reconstructing the decay of one B meson and identifying a charged lepton from the decay of the other B meson from {Upsilon}(4S) {yields} (B{bar B}) events. In one approach, we combine the inclusive {bar B} {yields} X{sub u}{ell}{bar {nu}} rate with a measurement of the inclusive B {yields} X{sub s}{gamma} photon energy spectrum. We obtain |V{sub ub}| = (4.43 {+-} 0.38{sub stat} {+-} 0.25{sub syst} {+-} 0.29{sub theo}) x 10{sup -3}. In another approach we measure the total {bar B} {yields} X{sub u} {ell}{bar {nu}} rate over the full phase space and find |V{sub ub}| = (3.84 {+-} 0.70{sub stat} {+-} 0.30{sub syst} {+-} 0.10{sub theo}) x 10{sup -3}.
Date: February 6, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Branching Fraction and P-violation Charge Asymmetry Measurements for B-meson Decays to eta K+-, eta pi+-, eta'K, eta' pi+-, omega K, and omega pi+-

Description: The authors present measurements of the branching fractions for B{sup 0} meson decays to {eta}{prime}K{sup 0} and {omega}K{sup 0}, and of the branching fractions and CP-violation charge asymmetries for B{sup +} meson decays to {eta}{pi}{sup +}, {eta}K{sup +}, {eta}{prime}{pi}{sup +}, {eta}{prime}K{sup +}, {omega}{pi}{sup +}, and {omega}K{sup +}. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 383 million B{bar B} pairs produced in e{sup +}e{sup -} annihilation. The measurements agree with previous results; they find no evidence for direct CP violation.
Date: June 28, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Branching Fraction Limits for B0 Decays to eta' eta, eta' pi0 and eta pi0

Description: We describe searches for decays to two-body charmless final states {eta}'{eta}, {eta}'{pi}{sup 0} and {eta}{pi}{sup 0} of B{sup 0} mesons produced in e{sup +}e{sup -} annihilation. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 232 million produced B{bar B} pairs. The results for branching fractions are, in units of 10{sup -6} (upper limits at 90% C.L.): {Beta}(B{sup 0} {yields} {eta}'{eta}) = 0.2{sub -0.5}{sup +0.7} {+-} 0.4 (< 1.7), {Beta}(B{sup 0} {yields} {eta}{pi}{sup 0}) = 0.6{sub -0.4}{sup +0.5} {+-} 0.1 (< 1.3), and {Beta}(B{sup 0} {yields} {eta}'{pi}{sup 0}) = 0.8{sub -0.6}{sup +0.8} {+-} 0.1 (< 2.1). The first error quoted is statistical and the second systematic.
Date: March 10, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Branching Fraction Measurement of B0 to D(*)-pi+and B- to D(*)0pi+ and Isospin Analyses of B to D(*)pi Decays

Description: Using 65 million {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring at the Stanford Linear Accelerator Center, they measure the color-favored branching fractions {Beta}({bar B}{sup 0} {yields} D{sup +}{pi}{sup -}) = (2.63 {+-} 0.05 {+-} 0.22) x 10{sup -3}, {Beta}({bar B}{sup 0} {yields} D*{sup +}{pi}{sup -}) = (2.79 {+-} 0.08 {+-} 0.18) x 10{sup -3}, {Beta}(B{sup -} {yields} D{sup 0}{pi}{sup -}) = (4.90 {+-} 0.07 {+-} 0.23) x 10{sup -3} and {Beta}(B{sup -} {yields} D*{sup 0} {pi}{sup -}) = (5.52 {+-} 0.17 {+-} 0.43) x 10{sup -3}, where the first error is statistical and the second is systematic. With these results and the current world average for the branching fraction for the color-suppressed decay {bar B}{sup 0} {yields} D{sup (*)0}{pi}{sup 0}, the cosines of the strong phase difference {delta} between the I = 1/2 and I = 3/2 isospin amplitudes are determined to be cos{sigma} = 0.860{sub -0.006-0.028}{sup +0.007+0.029} for the {bar B} {yields} D{pi} process and cos{sigma} = 0.917{sub -0.016-0.051}{sup +0.018+0.059} for the {bar B} {yields} D*{pi} process. The results for cos{delta} suggest that final-state interactions are presented in the D{pi} system.
Date: October 17, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Branching Fraction Measurements of B+ to rho+ gamma,B0 to rho0 gamma, and B0 to omega gamma

Description: The authors present a study of the decays B{sup +} {yields} {rho}{sup +}{gamma}, B{sup 0} {yields} {rho}{sup 0}{gamma}, and B{sup 0} {yields} {omega}{gamma}. The analysis is based on data containing 347 million B{bar B} events recorded with the BABAR detector at the PEP-II asymmetric B factory. They measure the branching fractions {Beta}(B{sup +} {yields} {rho}{sup +}{gamma}) = (1.10{sub -0.33}{sup +0.37} {+-} 0.09) x 10{sup -6} and {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) = (0.79{sub -0.20}{sup +0.22} {+-} 0.06) x 10{sup -6}, and set a 90% C.L. upper limit {Beta}(B{sup 0} {yields} {omega}{gamma}) < 0.78 x 10{sup -6}. They also measure the isospin-averaged branching fraction {Beta}[B {yields} ({rho}/{omega}){gamma}] = (1.25{sub -0.24}{sup +0.25} {+-} 0.09) x 10{sup -6}, from which they determine |V{sub td}/V{sub ts}| = 0.200{sub -0.020}{sup +0.021} {+-} 0.015, where the first uncertainty is experimental and the second is theoretical.
Date: January 3, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Branching Fractions and CP-Violating Asymmetries in Radiative B Decays to eta K gamma

Description: The authors present measurements of the CP-violation parameters S and C for the radiative decay B{sup 0} {yields} {eta}K{sub S}{sup 0}{gamma}; for B {yields} {eta}K{gamma} they also measure the branching fractions and for B{sup +} {yields} {eta}K{sup +}{gamma} the time-integrated charge asymmetry {Alpha}{sub ch}. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 465 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation. The results are S = -0.18{sub -0.46}{sup +0.49} {+-} 0.12, C = -0.32{sub -0.39}{sup +0.40} {+-} 0.07, {Beta}(B{sup 0} {yields} {eta}K{sup 0}{gamma}) = (7.1{sub -2.0}{sup +2.1} {+-} 0.4) x 10{sup -6}, {Beta}(B{sup +} {yields} {eta}K{sup +}{gamma}) = (7.7 {+-} 1.0 {+-} 0.4) x 10{sup -6}, and {Alpha}{sub ch} = (-9.0{sub -9.8}{sup +10.4} {+-} 1.4) x 10{sup -2}. The first error quoted is statistical and the second systematic.
Date: May 14, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

The e^+e^- -> 3(\pi^+\pi^-), 2(\pi^+\pi^-\pi^0) and K^+K^-2(\pi^+\pi^-) Cross Sections at Center-of-Mass Energies 0.5--4.5 GeV Measured with Initial-State Radiation

Description: We study the processes e{sup +}e{sup -} {yields} 3({pi}{sup +}{pi}{sup -}){gamma}, 2({pi}{sup +}{pi}{sup -}{pi}{sup 0}){gamma} and K{sup +}K{sup -} 2({pi}{sup +} {sup -}){gamma}, with the photon radiated from the initial state. About 20,000, 33,000 and 4,000 fully reconstructed events, respectively, have been selected from 232 fb{sup -1} of BABAR data. The invariant mass of the hadronic final state defines the effective e{sup +}e{sup -} center-of-mass energy, so that these data can be compared with the corresponding direct e{sup +}e{sup -} measurements. From the 3({pi}{sup +}{pi}{sup -}), 2({pi}{sup +}{pi}{sup -}{pi}{sup 0}) and K{sup +}K{sup -} 2({pi}{sup +}{pi}{sup -}) mass spectra, the cross sections for the processes e{sup +}e{sup -} {yields} 3({pi}{sup +}{sup -}), e{sup +}e{sup -} {yields} 2({pi}{sup +}{pi}{sup -}{pi}{sup 0}) and e{sup +}e{sup -} {yields} K{sup +}K{sup -} 2({pi}{sup +}{pi}{sup -}) are measured for center-of-mass energies from production threshold to 4.5 GeV. The uncertainty in the cross section measurement is typically 6-15%. We observe the J/{psi} in all these final states and measure the corresponding branching fractions.
Date: February 8, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department