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Measurements of the CKM Angle Beta/Phi(1) at the B Factories

Description: We report measurements of time-dependent CP asymmetries related to the CKM angle {beta}/{phi}{sub 1}, using decays of neutral B mesons to charmonium, open charm and in b {yields} s loop-dominated processes. A preliminary measurement of time-dependent CP asymmetries in B{sup 0} {yields} {rho}{sup 0}(770)K{sub S}{sup 0} decays from the BABAR experiment is given here.
Date: August 23, 2006
Creator: Ocariz, J. & /Paris U., VI-VII
Partner: UNT Libraries Government Documents Department

Search for B0 to K*+ K*-

Description: The authors report the results of a search for the decay B{sup 0} {yields} K*{sup +}K*{sup -} with a sample of 454 {+-} 5 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the Stanford Linear Accelerator Center. They obtain an upper limit at the 90% confidence level on the branching fraction for {Beta}(B{sup 0} {yields} K*{sup +}K*{sup -}) < 2.0 x 10{sup -6}, assuming the decay is fully longitudinally polarized.
Date: August 7, 2008
Creator: Aubert, B
Partner: UNT Libraries Government Documents Department

Time-dependent Dalitz Plot Analysis of B0 to D-K0Pi+ Decays

Description: We present for the first time a measurement of the weak phase 2{beta} + {gamma} obtained from a time-dependent Dalitz plot analysis of B{sup 0} {yields} D{sup {-+}}K{sup 0}{pi}{sup {+-}} decays. Using a sample of approximately 347 x 10{sup 6} B{bar B} pairs collected by the BABAR detector at the PEP-II asymmetric-energy storage rings, we obtain 2{beta} + {gamma} = (83 {+-} 53 {+-} 20){sup 0} and (263 {+-} 53 {+-} 20){sup o} assuming the ratio r of the b {yields} u and b {yields} c decay amplitudes to be 0.3. The magnitudes and phases for the resonances associated with the b {yields} c transitions are also extracted from the fit.
Date: January 8, 2008
Creator: Polci, F
Partner: UNT Libraries Government Documents Department

Measurements of CP-Violating Asymmetries and BranchingFractions in B Decays to omegaK and omegaPi

Description: We present measurements of CP-violating asymmetries and branching fractions for the decays B{sup +} {yields} {omega}{pi}{sup +}, B{sup +} {yields} {omega}K{sup +}, and B{sup 0} {yields} {omega}K{sup 0}. The data sample corresponds to 232 million B{bar B} pairs produced by e{sup +}e{sup -} annihilation at the {Upsilon}(4S) resonance. For the decay B{sup 0} {yields} {omega}K{sub s}{sup 0}, we measure the time-dependent CP-violation parameters S = 0.51{sub -0.39}{sup +0.35} {+-} 0.02, and C = -0.55{sub -0.26}{sup +0.28} {+-} 0.03. We also measure the branching fractions, in units of 10{sup -6}, {Beta}(B{sup +} {yields} {omega}{pi}{sup +}) = 6.1 {+-} 0.7 {+-} 0.4, {Beta}(B{sup +} {yields} {omega}K{sup +}) = 6.1 {+-} 0.6 {+-} 0.4, and {Beta}(B{sup 0} {yields} {omega}K{sup 0}) = 6.2 {+-} 1.0 {+-} 0.4, and charge asymmetries {Alpha}{sub ch}(B{sup +} {yields} {omega}{pi}{sup +}) = -0.01 {+-} 0.10 {+-} 0.01 and {Alpha}{sub ch}(B{sup +} {yields} {omega}K{sup +}) = 0.05 {+-} 0.09 {+-} 0.01.
Date: March 23, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Charmless Hadronic B Decays at BaBar

Description: We report recent measurements of branching fractions and charge asymmetries of charmless hadronic B decays using the data collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} collider.
Date: December 3, 2007
Creator: Mohanty, Gagan B. & Collaboration, for the BABAR
Partner: UNT Libraries Government Documents Department

Measurements of the Branching Fractions and CP Asymmetries of B -> D0_CP K Decays

Description: We present a study of the decay B{sup -} {yields} D{sub (CP)}{sup 0} K{sup -} and its charge conjugate, where D{sub (CP)}{sup 0} is reconstructed in CP-even, CP-odd, and non-CP flavor eigenstates, based on a sample of 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. We measure the partial-rate charge asymmetries AC{sub CP{+-}} and the ratios R{sub CP{+-}} of the B {yields} D{sup 0} K decay branching fractions as measured in CP{+-} and non-CP D{sup 0} decays: A{sub CP+} = 0.35 {+-} 0.13(stat) {+-} 0.04(syst), A{sub CP-} = -0.06 {+-} 0.13(stat) {+-} 0.04(syst), R{sub CP+} = 0.90 {+-} 0.12(stat) {+-} 0.04(syst), R{sub CP-} = 0.86 {+-} 0.10(stat) {+-} 0.05(syst).
Date: January 5, 2006
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department

Exclusive B Decays into Final States with Two Charmed Baryons

Description: This Thesis presents measurements of the decays B{sup -} {yields} {Xi}{sub c}{sup 0}{bar {Lambda}}{sub c}{sup -}, {bar B}{sup 0} {yields} {Xi}{sub c}{sup +}{bar {Lambda}}{sub c}{sup -}, B{sup -} {yields} {Lambda}{sub c}{sup +}{bar {Lambda}}{sub c}{sup -} K{sup -}, and {bar B}{sup 0} {yields} {Lambda}{sub c}{sup +}{bar {Lambda}}{sub c}{sup -} K{sub s}{sup 0} based on 228 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory.
Date: January 11, 2010
Creator: Chai, Xuedong & U., /Iowa
Partner: UNT Libraries Government Documents Department

Measurement of D^0-\overline{D^0} Mixing using the Ratio of Lifetimes for the Decays D^0 \to K^-\pi^+, K^-K^+, and \pi^-\pi^+

Description: The authors present a measurement of D{sup 0}-{bar D}{sup 0} mixing parameters using the ratios of lifetimes extracted from a sample of D{sup 0} mesons produced through the process D*{sup +} {yields} D{sup 0}{pi}{sup +}, that decay to K{sup -}{pi}{sup +}, I{sup -}K{sup +}, or {pi}{sup -}{pi}{sup +}. the Cabibbo-suppressed modes K{sup -}K{sup +} and {pi}{sup -}{pi}{sup +} are compared to the Cabibbo-favored mode K{sup -}{pi}{sup +} to obtain a measurement of ycp, which in the limit of CP conservation corresponds to the mixing parameter y. The analysis is based on a data sample of 384 fb{sup -1} collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider. They obtain ycp = [1.24 {+-} 0.39(stat) {+-} 0.13(syst)]%, which is evidence of D{sup 0}-{bar D}{sup 0} mixing at the 3{sigma} level, and {Delta}Y = [-0.26 {+-} 0.36(stat) {+-} 0.08(syst)]%, where {Delta}Y constrains possible CP violation. Combining this result with a previous BABAR measurement of ycp obtained from a separate sample of D{sup 0} {yields} K{sup -}K{sup +} events, they obtain ycp = [1.03 {+-} 0.33(stat) {+-} 0.19(syst)]%.
Date: January 8, 2008
Creator: Aubert, B
Partner: UNT Libraries Government Documents Department

Measurements of the CKM angle gamma at BaBar

Description: We report on our recent measurements of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} and of related CP-asymmetries and branching fraction ratios. The measurements have been performed on samples of up to 465 million B{bar B} pairs collected by the BABAR detector at the SLAC PEP-II asymmetric-energy B factory in the years 1999-2007.
Date: November 7, 2011
Creator: Marchiori, G. & /Pisa U. /INFN, Pisa
Partner: UNT Libraries Government Documents Department

Searches for B Meson Decays to Phiphi, Phirho, Phif0(980), and f0(980)f0(980) Final States

Description: We present the results of searches for B decays to charmless final states involving {phi}, f{sub 0}(980), and charged or neutral {rho} mesons. The data sample corresponds to 384 x 10{sup 6} B{bar B} pairs collected with the BABAR detector operating at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. We find no significant signals and determine the following 90% confidence level upper limits on the branching fractions, including systematic uncertainties: {Beta}(B{sup 0} {yields} {phi}{phi}) < 2.0 x 10{sup -7}, {Beta}(B{sup +} {yields} {phi}{rho}{sup +}) < 30 x 10{sup -7}, {Beta}(B{sup 0} {yields} {phi}{rho}{sup 0}) < 3.3 x 10{sup -7}, {Beta}[B{sup 0} {yields} {phi}f{sub 0}(980)] x {Beta}[f{sub 0}(980) {yields} {pi}{sup +}{pi}{sup -}] < 3.8 x 10{sup -7}, and {Beta}[B{sup 0} {yields} f{sub 0}(980)f{sub 0}(980)] x {Beta}[f{sub 0}(980) {yields} {pi}{sup +}{pi}{sup -}] x {Beta}[f{sub 0}(980) {yields} K{sup +}K{sup -}] < 2.3 x 10{sup -7}.
Date: August 1, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department

Measurements of Branching Fractions, Polarizations, and Direct CP-Violation Asymmetries in B to rho K* and B to f0(980) K* Decays

Description: The authors report searches for B-meson decays to the charmless final states {rho}K* and f{sub 0}(980)K* with a sample of 232 million B{bar B} pairs 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

Observation of B^+ to Phi Phi K^+ and Evidence for B^0 to Phi Phi K^0 below Eta_C Threshold.

Description: The authors report measurements of the decays B{sup +} {yields} {phi}{phi}K{sup +} and B{sup 0} {yields} {phi}{phi}K{sup 0} using a sample of 231 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The branching fractions are measured to be {Beta}(B{sup +} {yields} {phi}{phi}K{sup +}) = (7.5 {+-} 1.0(stat) {+-} 0.7(syst)) x 10{sup -6} and {Beta}(B{sup 0} {yields} {phi}{phi}K{sup 0}) = (4.1{sub -1.4}{sup +1.7}(stat) {+-} 0.4(syst)) x 10{sup -6} for a {phi}{phi} invariant mass below 2.85 GeV/c{sup 2}.
Date: November 30, 2006
Creator: Aubert, B.; Bona, M.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department

CP Violation Measurements in B to Charm Decays at BaBar

Description: This article summarizes measurements of time-dependent CP asymmetries in decays of neutral B mesons to charm final states using data collected by the BABAR detector at the PEP-II asymmetric-energy B factory. All results are preliminary unless otherwise stated.
Date: October 11, 2006
Creator: George, Katherine A.
Partner: UNT Libraries Government Documents Department

Radiative B Decays

Description: I discuss recent results in radiative B decays from the Belle and BaBar collaborations. I report new measurements of the decay rate and CP asymmetries in b {yields} s{gamma} and b {yields} d{gamma} decays, and measurements of the photon spectrum in b {yields} s{gamma}. Radiative penguin decays are flavour changing neutral currents which do not occur at tree level in the standard model (SM), but must proceed via one loop or higher order diagrams. These transitions are therefore suppressed in the SM, but offer access to poorlyknown SM parameters and are also a sensitive probe of new physics. In the SM, the rate is dominated by the top quark contribution to the loop, but non-SM particles could also contribute with a size comparable to leading SM contributions. The new physics effects are potentially large which makes them theoretically very interesting, but due to their small branching fractions they are typically experimentally challenging.
Date: November 23, 2011
Creator: Bard, D. & /Imperial Coll., London
Partner: UNT Libraries Government Documents Department