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Observation of Y(3940) to J/psi omega in B to J/psi omega K at BABAR

Description: The authors report the results of a study of the decays B{sup +} {yields} J/{psi}{omega}K{sup +} and B{sup 0} {yields} J/{psi}{omega}K{sub S}{sup 0} using 383 million B{bar B} events from {Upsilon}(4S) decays with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage rings. They observe evidence for Y(3940) {yields} J/{psi}{omega} with product branching fractions {Beta}(B{sup +} {yields} Y K{sup +}, Y {yields} J/{psi}{omega}) = (4.9 {+-} 1.0(stat) {+-} 0.5(syst)) x 10{sup -5} and {Beta}(B{sup 0} {yields} Y K{sup 0}, Y {yields} J/{psi}{omega}) = (1.5{sub -1.2}{sup +1.4}(stat){sub -0.2}{sup +0.2}(syst)) x 10{sup -5}. The measured mass and width are M(Y) = (3914.6{sub -3.4}{sup +3.8}(stat){sub -1.9}{sup +1.9}(syst)) MeV/c{sup 2} and {Lambda}(Y) = (33{sub -8}{sup +12}(stat){sub -5}{sup +5}(syst)) MeV, respectively.
Date: December 4, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of D^0-\bar{D^0} Mixing From a Time-Dependent Amplitude Analysis of D^0\ -> K^+\pi^-\pi0 Decays

Description: The authors present evidence of D{sup 0}-{bar D}{sup 0} mixing using a time-dependent amplitude analysis of the decay D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} in a data sample of 384 fb{sup -1} collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. Assuming CP conservation, they measure the mixing parameters x{prime}{sub K{pi}{pi}{sup 0}} = [2.61{sub -0.68}{sup +0.57}(stat.) {+-} 0.39(syst.)]%, y{prime}{sub K{pi}{pi}{sup 0}} = [-0.06{sub -0.64}{sup +0.55}(stat.) {+-} 0.34(syst.)]%. The confidence level for the data to be consistent with the no-mixing hypothesis is 0.1%, including systematic uncertainties. This result is inconsistent with the no-mixing hypothesis with a significance of 3.2 standard deviations. They find no evidence of CP violation in mixing.
Date: August 4, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E. et al.
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

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

Study of the decay B0bar -> D* omega pi

Description: We report on a study of the decay {bar B}{sup 0} {yields} D*{sup +}{omega}{pi}{sup -} with the BABAR detector at the PEP-II B-factory at the Stanford Linear Accelerator Center. Based on a sample of 232 million B{bar B} decays, we measure the branching fraction {Beta}({bar B}{sup 0} {yields} D*{sup +}{omega}{pi}{sup -}) = (2.88 {+-} 0.21(stat.) {+-} 0.31(syst.)) x 10{sup -3}. We study the invariant mass spectrum of the {omega}{pi}{sup -} system in this decay. This spectrum is in good agreement with expectations based on factorization and the measured spectrum in {tau}{sup -} {yields} {omega}{pi}{sup -} {nu}{sub {tau}}. We also measure the polarization of the D*{sup +} as a function of the {omega}{pi}{sup -} mass. In the mass region 1.1 to 1.9 GeV we measure the fraction of longitudinal polarization of the D*{sup +} to be {Lambda}{sub L}/{Lambda} = 0.654 {+-} 0.042(stat.) {+-} 0.016(syst.). This is in agreement with the expectations from heavy-quark effective theory and factorization assuming that the decay proceeds as {bar B}{sup 0} {yields} D*{sup +}{rho}(1450), {rho}(1450) {yields} {omega}{pi}{sup -}.
Date: April 24, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Search for B+ Meson Decay to a1+ K*0

Description: We present the preliminary result of a search for the decay B{sup {+-}} {yields} a{sub 1}{sup {+-}} K*{sup 0}. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 465 million B{bar B} pairs produced in e{sup +}e{sup -} annihilation at the {Upsilon}(4S) energy. The result for the branching fraction is: {Beta}(B{sup +} {yields} a{sub 1}{sup +}K*{sup 0}) x {Beta}(a{sub 1}{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +}) = (0.7{sub -0.4-0.7}{sup +0.5+0.7}) x 10{sup -6}, corresponding to an upper limit at 90% confidence level of 1.6 x 10{sup -6}. The first error quoted is statistical, the second systematic.
Date: August 7, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Search for B Meson Decays to eta' eta' K

Description: The authors describe searches for decays of B mesons to the charmless final states {eta}'{eta}'K. The data consist of 228 million B{bar B} pairs produced in e{sup +}e{sup -} annihilation, collected with the BABAR detector at the Stanford Linear Accelerator Center. The 90% confidence level upper limits for the branching fractions are {Beta}(B{sup 0} {yields} {eta}'{eta}'K{sup 0}) < 31 x 10{sup -6} and {Beta}(B{sup +} {yields} {eta}'{eta}'K{sup +}) < 25 x 10{sup -6}.
Date: May 5, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Search for B+ to X(3872) K+, X(3872) to J/psi gamma

Description: In a study of B{sup +} {yields} J/{psi}{gamma}K{sup +} decays, they find evidence for the radiative decay X(3872) {yields} J/{psi}{gamma} with a statistical significance of 3.4{sigma}. They measure the product of branching fractions {Beta}(B{sup +} {yields} X(3872)K{sup +}) {center_dot} {Beta}(X(3872) {yields} J/{psi}{gamma}) = (3.3 {+-} 1.0 {+-} 0.3) x 10{sup -6}, where the uncertainties are statistical and systematic, respectively. They also measure the branching fraction {Beta}(B{sup +} {yields} {chi}{sub c1}K{sup +}) = (4.9 {+-} 0.20 {+-} 0.4) x 10{sup -4}. These results are obtained from (287 {+-} 3) million B{bar B} decays collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II B Factory at SLAC.
Date: July 31, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Search for Lepton Flavour Violating Decays tau- to l- Ks with the BaBar experiment

Description: A search for the lepton flavor violating decays {tau}{sup -} {yields} l{sup -} K{sub S}{sup 0} (l = e or {mu}) has been performed using a data sample corresponding to an integrated luminosity of 469 fb{sup -1}, collected with the BABAR detector at the SLAC PEP-II e{sup +}e{sup -} asymmetric energy collider. No statistically significant signal has been observed in either channel and the estimated upper limits on branching fractions are {Beta}({tau}{sup -} {yields} e{sup -} K{sub S}{sup 0}) < 3.3 x 10{sup -8} and {Beta}({tau}{sup -} {yields} {mu}{sup -}K{sub S}{sup 0}) < 4.0 x 10{sup -8} at 90% confidence level.
Date: January 6, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department

A Simultaneous Measurement of the Branching Fractions of Ten B to Double Charm Decays

Description: This dissertation presents a simultaneous measurement of the branching fractions of ten B {yields} D{sup (*)}{bar D}{sup (*)} decays. The measurements are derived from a sample of 2.32 x 10{sup 8} B{bar B} pairs collected by the BABAR detector at the PEP-II B Factory located at Stanford Linear Accelerator Center. The branching fractions (x 10{sup -4}) are: -0.10 {+-} 0.44 {+-} 0.15 (<0.59) for B{sup 0} {yields} D{sup 0}{bar D}{sup 0}; 1.01 {+-} 1.07 {+-} 0.35 (<2.92) for B{sup 0} {yields} D*{sup 0}{bar D}{sup 0}; -1.31 {+-} 1.05 {+-} 0.41 (<0.92) for B{sup 0} {yields} D*{sup 0}{bar D}*{sup 0}; 2.81 {+-} 0.43 {+-} 0.45 for B{sup 0} {yields} D{sup +}D{sup -}; 5.72 {+-} 0.64 {+-} 0.71 for B{sup 0} {yields} D*{sup +}D{sup -}; 8.11 {+-} 0.57 {+-} 0.97 for B{sup 0} {yields} D*{sup +}D*{sup -}; 3.76 {+-} 0.57 {+-} 0.45 for B{sup -} {yields} D{sup -}D{sup 0}; 3.56 {+-} 0.52 {+-} 0.39 for B{sup -} {yields} D*{sup -}D{sup 0}; 6.30 {+-} 1.32 {+-} 0.93 for B{sup -} {yields} D{sup -}D*{sup 0}; and 8.14 {+-} 1.17 {+-} 1.11 for B{sup -} {yields} D*{sup -}D*{sup 0}. The first uncertainty is statistical while the second is systematic. The number in parentheses is the 90% upper limit using the Feldman-Cousins method with systematic uncertainties taken into account. These measurements are consistent with the Standard Model predictions using the factorization assumption.
Date: January 16, 2008
Creator: Lae, Chung Khim & U., /Maryland
Partner: UNT Libraries Government Documents Department

Production and Decay of Omega_c^0

Description: We present an analysis of inclusive {Omega}{sub c}{sup 0} baryon production and decays in 230.5 fb{sup -1} of data recorded with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the Stanford Linear Accelerator Center. {Omega}{sub c}{sup 0} baryons are reconstructed in four final states ({Omega}{sup -}{pi}{sup +}, {Omega}{sup -}{pi}{sup +}{pi}{sup 0}, {Omega}{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -}, {Xi}{sup -}K{sup -}{pi}{sup +}{pi}{sup +}) and the ratios of branching fractions for these final states are measured. We also measure the momentum spectrum of the {Omega}{sub c}{sup 0} baryons in the e{sup +}e{sup -} center-of-mass frame. From the spectrum, they observe {Omega}{sub c}{sup 0} production from B decays and in c{bar c} events, and extract the two rates of production.
Date: March 21, 2007
Creator: Aubert, B
Partner: UNT Libraries Government Documents Department

Measurement of th eta and etaprime Transition Form Factors at q^2 = 112 GeV^2

Description: The authors report a study of the processes e{sup +}e{sup -} {yields} {eta}{gamma} and e{sup +}e{sup -} {yields} {eta}'{gamma} at a center-of-mass energy of 10.58 GeV, using a 232 fb{sup -1} data sample collected with the BABAR detector at the PEP-II collider at SLAC.
Date: May 16, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of time dependent CP asymmetry parameters in B0 meson decays to omegaKs, etaprimeKz, and pi0Ks

Description: The authors present measurements of the time-dependent CP-violation parameters S and C in the decays B{sup 0} {yields} {omega}K{sub S}{sup 0}, B{sup 0} {yields} {eta}{prime}K{sup 0}, reconstructed as {eta}{prime}K{sub S}{sup 0} and {eta}{prime}K{sub L}{sup 0}, and B{sup 0} {yields} {pi}{sup 0}K{sub S}{sup 0}. The data sample corresponds to the full BABAR dataset of 467 x 10{sup 6} B{bar B} pairs produced at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the Stanford Linear Accelerator Center. The results are S{sub {omega}K{sub S}{sup 0}} = 0.55{sub -0.29}{sup +0.26} {+-} 0.02, C{sub {omega}K{sub S}{sup 0}} = -0.52{sub -0.20}{sup +0.22} {+-} 0.03, S{sub {eta}{prime}K{sup 0}} = 0.57 {+-} 0.08 {+-} 0.02, C{sub {eta}{prime}K{sup 0}} = -0.08 {+-} 0.06 {+-} 0.02, S{sub {pi}{sup 0}K{sub S}{sup 0}} = 0.55 {+-} 0.20 {+-} 0.03, and C{sub {pi}{sup 0}K{sub S}{sup 0}} = 0.13 {+-} 0.13 {+-} 0.03, where the first errors are statistical and the second systematic. These results are consistent with the previous measurements and the world average of sin2{beta} measured in B{sup 0} {yields} J/{psi}K{sub S}{sup 0}.
Date: September 10, 2008
Creator: Aubert, : B.
Partner: UNT Libraries Government Documents Department

Dalitz Plot Analysis of B- -> D+ pi- pi-

Description: The author reports on a Dalitz plot analysis of B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -} decays, based on a sample of about 383 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. They find the total branching fraction of the three-body decay: {Beta}(B{sup -} {yields} D{sup +} {pi}{sup -}{pi}{sup -}) = (1.08 {+-} 0.01 {+-} 0.05) x 10{sup -3}. the masses and widths of D*{sub 2}{sup 0} and D*{sub 0}{sup 0}, the 2{sup +} and 0{sup +} c{bar u} P-wave states decaying to D{sup +}{pi}{sup -}, are measured: m{sub D*{sub 2}{sup 0}} = (2460.4 {+-} 1.2 {+-} 1.2 {+-} 1.9) MeV/c{sup 2}, {Lambda}{sub D*{sub 2}{sup 0}} = (41.8 {+-} 2.5 {+-} 2.1 {+-} 2.0) MeV, m{sub D*{sub 0}{sup 0}} = (2297 {+-} 8 {+-} 5 {+-} 19) MeV/c{sup 2} and {Lambda}{sub D*{sub 0}{sup 0}} = (273 {+-} 12 {+-} 17 {+-} 45) MeV. The stated errors reflect the statistical and systematic uncertainties, and the uncertainty related to the assumed composition of signal events and the theoretical model.
Date: January 29, 2009
Creator: Aubert, : B.
Partner: UNT Libraries Government Documents Department

B Meson Decays to Quasi-Two-Body Charmless Final States at BaBar

Description: The authors present results for measurement of the decays to charmless final states of B{sup 0} meson to {eta}K{sup 0}, {eta}{omega}, a{sub 1}{sup +}(1260){pi}{sup -} with a{sub 1}{sup +}(1260) {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -}, and of B{sup +} to {eta}{rho}{sup +}, {eta}{prime}{pi}{sup +}. Analyses are based on data taken with the BABAR detector at the PEP-II asymmetric e{sup +}e{sup -} collider at SLAC.
Date: November 1, 2005
Creator: Lazzaro, A. & /Milan U. /INFN, Milan
Partner: UNT Libraries Government Documents Department

Measurements of CKM Angle Beta from BaBar

Description: We present recent results of hadronic B meson decays related to the CKM angle beta. The data used were collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider operating at the Upsilon(4S) resonance located at the Stanford Linear Accelerator Center.
Date: May 23, 2007
Creator: Ulmer, Keith A. & U., /Colorado
Partner: UNT Libraries Government Documents Department

Measurements of CP-Violating Asymmetries in B^0 toa_1^+(1260) \pi^- Decays

Description: The authors present measurements of CP-violating asymmetries in the 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 384 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric B-factory at SLAC. They measure the CP-violating asymmetry {Alpha}{sub CP}{sup a{sub 1}{pi}} = -0.07 {+-} 0.07 {+-} 0.02, the mixing-induced CP violation parameter S{sub a{sub 1}{pi}} = 0.37 {+-} 0.21 {+-} 0.07, the direct Cp violation parameter C{sub a{sub 1}{pi}} = -0.10 {+-} 0.15 {+-} 0.09, and the parameters {Delta}C{sub a{sub 1}{pi}} = 0.26 {+-} 0.15 {+-} 0.07 and {Delta}S{sub a{sub 1}{pi}} = -0.14 {+-} 0.21 {+-} 0.06. From these measured quantities they determine the angle {alpha}{sub eff} = 78.6{sup o} {+-} 7.3{sup o}.
Date: January 5, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurements of CP-Violating Asymmetries in the Decay B0 to K+ K- K0

Description: The authors analyze the decay B{sup 0} {yields} K{sup +}K{sup -}K{sup 0} using 383 million B{bar B} events collected by the BABAR detector at SLAC to extract CP violation parameter values over the Dalitz plot. Combining all K{sup +}K{sup -}K{sup 0} events, they find A{sub CP} = -0.015 {+-} 0.077 {+-} 0.053 and {beta}{sub eff} = 0.352 {+-} 0.076 {+-} 0.026 rad, corresponding to a CP violation significance of 4.8{sigma}. A second solution near {pi}/2 - {beta}{sub eff} is disfavored with a significance of 4.5{sigma}. They also report A{sub CP} and {beta}{sub eff} separately for decays to {phi}(1020)K{sup 0}, f{sub 0}(980)K{sup 0}, and K{sup +}K{sup -}K{sup 0} with m{sub K{sup +}K{sup -}} > 1.1 GeV/c{sup 2}.
Date: June 27, 2007
Creator: Collaboration, The BABAR & Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of Branching Fractions in Radiative BDecays to eta K gamma and Search for B Decays to eta' K gamma

Description: The authors present measurements of the B {yields} {eta}K{gamma} branching fractions and upper limits for the B {yields} {eta}'K{gamma} branching fractions. For B{sup +} {yields} {eta}K{sup +}{gamma} they also measure the time-integrated charge asymmetry. The data sample, collected with the BABAR detector at the Stanford Linear Accelerator Center, represents 232 x 10{sup 6} produced B{bar B} pairs. The results for branching fractions and upper limits at 90% C.L. in units of 10{sup -6} are: {Beta}(B{sup 0} {yields} {eta}K{sup 0}{gamma}) = 11.3{sub -2.6}{sup +2.8} {+-} 0.6, {Beta}(B{sup +} {yields} {eta}K{sup +}{gamma}) = 10.0 {+-} 1.3 {+-} 0.5, {Beta}(B{sup 0} {yields} {eta}'K{sup 0}{gamma}) < 6.6, {Beta}(B{sup +} {yields} {eta}'K{sup +}{gamma}) < 4.2. The charge asymmetry in the decay B{sup +} {yields} {eta}K{sup +}{gamma} is {Alpha}{sub ch} = -0.09 {+-} 0.12 {+-} 0.01. The first errors are statistical and the second systematic.
Date: March 31, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurement of B0bar -> D(*)0 K(*)0bar BranchingFractions

Description: The authors present a study of the decays {bar B}{sup 0} {yields} D{sup (*)0}{bar K}{sup (*)0} using a sample of 226 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. They report evidence for the decay of B{sup 0} and {bar B}{sup 0} mesons to the D*{sup 0}K{sub S}{sup 0} final state with an average branching fraction {Beta}({bar B}{sup 0} {yields} D*{sup 0} {bar K}{sup 0}) {triple_bond} {Beta}({bar B}{sup 0} {yields} D*{sup 0} {bar K}{sup 0}) + {Beta}(B{sup 0} {yields} D*{sup 0}K{sup 0})/2 = (3.6 {+-} 1.2 {+-} 0.3) x 10{sup -5}.
Date: April 10, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Measurements of CKM angles beta/phi_1 and alpha/phi_2 at the Babar and Belle experiments.

Description: We report measurements of the CKM angles {beta}/{phi}{sub 1} and {alpha}/{phi}{sub 2} done by the BABAR and Belle experiments. Both experiments have collected large data samples, corresponding to a total of more than 1 billion of B{bar B} pairs, at the e{sup +}e{sup -} asymmetric-energy colliders PEP-II (SLAC) and KEK-B (KEK), respectively.
Date: May 7, 2009
Creator: Lazzaro, A.
Partner: UNT Libraries Government Documents Department

Measurement of D0-D0bar Mixing using the Ratio of D0->K-pi and K-K Lifetimes

Description: We measure the rate of D{sup 0}-{bar D}{sup 0} mixing with the observable y{sub CP} = ({tau}{sub K{pi}}/{tau}{sub KK}) - 1, where {tau}{sub KK} and {tau}{sub K{pi}} are respectively the mean lifetimes of CP-even D{sup 0} {yields} K{sup +}K{sup -} and CP-mixed D{sup 0} {yields} K{sup -}{pi}{sup +} decays, using a data sample of 384 fb{sup -1} collected by the BABAR detector at the SLAC PEP-II asymmetric-energy B Factory. From a sample of D{sup 0} and {bar D}{sup 0} decays where the initial flavor of the decaying meson is not determined, we obtain y{sub CP} = [1.12 {+-} 0.26(stat) {+-} 0.22(syst)]%, which excludes the no-mixing hypothesis at 3.3{sigma}, including both statistical and systematic uncertainties. This result is in good agreement with a previous BABAR measurement of y{sub CP} obtained from a sample of D*{sup +} {yields} D{sup 0}{pi}{sup +} events, where the D{sup 0} decays to K{sup -}{pi}{sup +}, K{sup +}K{sup -}, and {pi}{sup +}{pi}{sup -}, which is disjoint with the untagged D{sup 0} events used here. Combining the two results taking into account statistical and systematic uncertainties, where the systematic uncertainties are assumed to be 100% correlated, we find y{sub CP} = [1.16 {+-} 0.22(stat) {+-} 0.18(syst)]%, which excludes the no-mixing hypothesis at 4.1{sigma}.
Date: October 17, 2009
Creator: Aubert, B.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Partner: UNT Libraries Government Documents Department

Measurement of the angle alpha at BABAR

Description: The authors present recent measurements of the CKM angle {alpha} using data collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory, operating at the {Upsilon}(4S) resonance. They present constraints on {alpha} from B {yields} {pi}{pi}, B {yields} {rho}{rho} and B {yields} {rho}{pi} decays.
Date: June 25, 2009
Creator: Perez, A. & /Orsay, LAL
Partner: UNT Libraries Government Documents Department