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United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

We perform a Dalitz plot analysis of about 100 000 Ds+ [D subscript s superscript +] decays to K+K-π+ [K superscript + K superscript - pi superscript +] and measure the complex amplitudes of the intermediate resonances which contribute to this decay mode. We also measure the relative branching fractions of Ds+[D subscript s superscript +] →K+K+π- [K superscript + K superscript + pi superscript -] and Ds+ [D subscript s superscript +] →K+K+K- [K superscript + K superscript + K superscript -]. For this analysis we use a 384 fb-1 [fb superscript -1] data sample, recorded by the BABAR detector at the PEP-II asymmetric-energy e+e- [e superscript + superscript -] collider running at center-of-mass energies near 10.58 GeV., United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

Using 347.5 fb-1 [fb superscript -1] of data recorded by the BABAR detector at the PEP-II electron-positron collider, 244×103 [244 X 10 superscript 3] signal events for the D+→K-π+e+νe [D superscript + → K superscript - pi superscript + e superscript + v subscript e] decay channel are analyzed. This decay mode is dominated by the K̅ *(892)0 [K overscore superscript * (892) superscript 0] contribution. We determine the K̅ *(892)0 [K overscore superscript * (892) superscript 0] parameters: mK*(892)0=(895.4±0.2±0.2) [m subscript K * (892) 0 = 895.4±0.2±0.2)] MeV/c2 [MeV / c superscript 2], ΓK*(892)00=(46.5±0.3±0.2) [Gamma superscript 0 subscript K * (892) 0 = (46.5±0.3±0.2)] MeV/c2 [MeV / c superscript 2], and the Blatt-Weisskopf parameter rBW=2.1±0.5±0.5 [r subscript BW = 2.1±0.5±0.5](GeV/c)-1 [(GeV / c) superscript -1], where the first uncertainty comes from statistics and the second from systematic uncertainties. We also measure the parameters defining the corresponding hadronic form factors at q2=0 [q superscript 2 =0](rV=V(0)/A1(0)=1.463±0.017±0.031 [r subscript V = V(0) over A subscript 1 (0) = 1.463±0.017±0.031], r2=A2(0)/A1(0)=0.801±0.020±0.020 [r subscript 2 = A subscript 2 (0) over A subscript 1 (0) = 0.801±0.020±0.020]) and the value of the axial-vector pole mass parametrizing the q2 [q superscript 2] variation of A1 [A subscript 1] and A2 [A subscript 2]: mA=(2.63±0.10±0.13) [m subscript A = (2.63±0.10±0.13)] GeV/c2 [GeV / c superscript 2]. The S-wave fraction is equal to (5.79±0.16±0.15)%. Other signal components correspond to fractions below 1%. Using the D+→K-π+π+ [D superscript + → K superscript - pi superscript + pi superscript -] channel as a normalization, we measure the D+ [D superscript +] semileptonic branching fraction: B(D+→K-π+e+νe)=(4.00±0.03±0.04±0.09)×10-2 [Beta (D superscript + → K superscript - pi superscript + e superscript + v subscript e) = (4.00±0.03±0.04±0.09) X 10 superscript -2], where the third uncertainty comes from external, United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

We report on a search for CP violation in the decay D±→KS0π± [D superscript + - → K superscript 0 subscript X pi superscript + -] using a data set corresponding to an integrated luminosity of 469 fb-1 [fb superscript -1] collected with the BABAR detector at the PEP-II asymmetric energy e+e- [e superscript + e uperscript -] storage rings. The CP-violating decay rate asymmetry ACP is determined to be (-0.44±0.13(stat)±0.10(syst))%, consistent with zero at 2.7σ [2.7 sigma] and with the standard model prediction of (-0.332±0.006)%. This is currently the most precise measurement of this parameter., United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

We report on analyses of tau lepton decays τ-→ηK-ντ [tau superscript - → eta kappa superscript - nu subscript tau] and τ-→ηπ-ντ tau superscript - → eta pi superscript - nu subscript tau], with η→π+π-π0 [eta → pi superscript + pi superscript - pi superscript 0], , using 470 fb-1 [fb superscript -1] of data from the BABAR experiment at PEP-II, collected at center-of-mass energies at and near the Υ(4S) [upsilon (4S)] resonance. We measure the branching fraction for the τ-→ηK-ντ [tau superscript - → eta kappa superscript - nu subscript tau] decay mode, B(τ-→ηK-ντ)=(1.42±0.11(stat)±0.07(syst))×10-4 [Beta (tau superscript - → eta kappa superscript - nu subscript tau) =(1.42±0.11(stat)±0.07(syst)) times 10 superscript 4], and report a 95% confidence level upper limit for the second-class current process τ-→ηπ-ντ, B(τ-→ηπ-ντ)<9.9×10-5 [tau superscript - → eta pi superscript - nu subscript tau, beta (tau superscript - → eta pi superscript - nu subscript tau),9.9 times 10 superscript 5]., United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

We report the result of a search for the rare decay B0→γγ [B superscript 0→γγ] in 426 fb-1 [fb superscript -1] of data, corresponding to 226×106 B0B̅ 0 [226 x 10 superscript 6 B superscript 0 B̅ superscript 0] pairs, collected on the Υ(4S) resonance at the PEP-II asymmetric-energy e+e- [e superscript + e superscript -] collider using the BABAR detector. We use a maximum likelihood fit to extract the signal yield and observe 21-12+13 [21 subscript -12 superscript +13] signal events with a statistical significance of 1.8σ [1.8 delta]. This corresponds to a branching fraction B(B0→γγ)=(1.7±1.1(stat.)±0.2(syst.))×10-7 [B(B superscript 0→γγ) = (1.7±1.1(stat.)±0.2(syst.))×10 superscript -7]. Based on this result, we set a 90% confidence level upper limit of B(B0→γγ)<3.2×10-7 [B(B superscript 0→γγ)<3.2×10 superscript -7]., United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

We report a search for the rare decays B+→D+K0 [B superscript + → D superscript + K superscript 0] and B+→D+K*0 [B superscript + → D superscript + K superscript *0] in an event sample of approximately 465×106 BB̅ pairs collected with the BABAR detector at the PEP-II asymmetric-energy e+e- [e superscript + e superscript -] collider at SLAC National Accelerator Laboratory. We find no significant evidence for either mode and we set 90% probability upper limits on the branching fractions of B [beta](B+→D+K0) <2.9×10-6 [B superscript + → D superscript + K superscript 0 <2.9 x 10 superscript -6]and B [beta] (B+→D+K*0)<3.0×10-6 [B superscript + → D superscript + K superscript *0 <3.0 x 10 superscript -6]., United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

We present a study of the D+π- [D superscript + pi superscript -], D0π+ [D superscript 0 pi superscript *], and D*+π- [D superscript *+ pi superscript -] systems in inclusive e+e-→cc̅ [e superscript + e superscript - → cc̅] interactions in a search for new excited D meson states. We use a data set, consisting of ~454 fb-1 [fb superscript -1], collected at center-of-mass energies near 10.58 GeV by the BABAR detector at the SLAC PEP-II asymmetric-energy collider. We observe, for the first time, candidates for the radial excitations of the D0 [D superscript 0], D*0 [D superscript *0], and D*+ [D superscript *+], as well as the L=2 excited states of the D0 [D superscript 0] and D+ [D superscript +], where L is the orbital angular momentum of the quarks., United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

We report a search for the rare decays B+→D+K0 [B superscript + → D superscript + K superscript 0] and B+→D+K*0 [B superscript + → D superscript + K superscript *0] in an event sample of approximately 465×106 BB̅ pairs collected with the BABAR detector at the PEP-II asymmetric-energy e+e- [e superscript + e superscript -] collider at SLAC National Accelerator Laboratory. We find no significant evidence for either mode and we set 90% probability upper limits on the branching fractions of B [beta](B+→D+K0) <2.9×10-6 [B superscript + → D superscript + K superscript 0 <2.9 x 10 superscript -6]and B [beta] (B+→D+K*0)<3.0×10-6 [B superscript + → D superscript + K superscript *0 <3.0 x 10 superscript -6]., United States. Dept. of Energy, National Science Foundation (U.S.), Alfred P. Sloan Foundation

National Science Foundation (U.S.), United States. Dept. of Energy, Natural Sciences and Engineering Research Council of Canada, France. Commissariat à l'Energie Atomique, Institut national de physique nucléaire et de physique des particules, Germany. Bundesministerium für Bildung und Forschung, Deutsche Forschungsgemeinschaft, Istituto nazionale di fisica nucleare, Stichting voor Fundamenteel Onderzoek der Materie, Norges forskningsråd, Russia (Federation). ǂb Ministerstvo obrazovanii︠a︡ i nauki, Spain. Ministerio de Educación y Ciencia, Science and Technology Facilities Council (Great Britain), Marie Curie International Fellowship, Alfred P. Sloan Foundation

United States. Dept. of Energy, National Science Foundation, Natural Sciences and Engineering Research Council of Canada, Institut National de Physique Nucléaire and de Physique des Particules, Bundesministerium für Bildung und Forschung, Germany, Deutsche Forschungsgemeinschaft, Istituto Nazionale di Fisica Nucleare of Italy, FOM of the Netherlands, Norges forskningsråd, MES (Russia), MEC (Spain), Science and Technology Facilities Council, United Kingdom

Searches for lepton-flavor-violating decays of a τ lepton to a lighter mass lepton and a photon have been performed with the entire data set of (963±7)×10[superscript 6] τ decays collected by the BABAR detector near the Υ(4S), Υ(3S) and Υ(2S) resonances. The searches yield no evidence of signals and we set upper limits on the branching fractions of B(τ[superscript ±]→e[superscript ±]γ)<3.3×10[superscript -8] and B(τ[superscript ±]→μ[superscript ±]γ)<4.4×10[superscript -8] at 90% confidence level., United States. Dept. of Energy, National Science Foundation, Natural Sciences and Engineering Research Council of Canada, Institut National de Physique Nucléaire and de Physique des Particules, Bundesministerium für Bildung und Forschung, Germany, Deutsche Forschungsgemeinschaft, Istituto Nazionale di Fisica Nucleare of Italy, FOM of the Netherlands, Norges forskningsråd, MES (Russia), MEC (Spain), Science and Technology Facilities Council, United Kingdom

We study the decay B[superscript -]→DK[superscript *-] using a sample of 379×10[superscript 6] Υ(4S)→BB̅ events collected with the BABAR detector at the PEP-II B factory. We perform a Gronau-London-Wyler analysis where the D meson decays into either a CP-even (CP+) eigenstate (K[superscript +]K[superscript -], π[superscript +]π[superscript -]), CP-odd (CP-) eigenstate (KS[superscript 0]π[superscript 0], K[subscript S][superscript 0]ϕ, K[subscript S][superscript 0]ω) or a non-CP state (K[superscript -]πsuperscript +]). We also analyze D meson decays into Ksuperscript +]πsuperscript -] from a Cabibbo-favored D̅ 0 decay or doubly suppressed D0 decay [Atwood-Dunietz-Soni (ADS) analysis]. We measure observables that are sensitive to the Cabibbo-Kobayashi-Maskawa angle γ: the partial-rate charge asymmetries A[subscript CP±], the ratios R[subscript CP±] of the B-decay branching fractions in CP± and non-CP decay, the ratio R[subscript ADS] of the charge-averaged branching fractions, and the charge asymmetry A[subscript ADS] of the ADS decays: A[subscript CP+]=0.09±0.13±0.06, A[subscript CP-]=-0.23±0.21±0.07, R[subscript CP+]=2.17±0.35±0.09, R[subscript CP-]=1.03±0.27±0.13, R[subscript ADS]=0.066±0.031±0.010, and A[subscript ADS]=-0.34±0.43±0.16, where the first uncertainty is statistical and the second is systematic. Combining all the measurements and using a frequentist approach yields the magnitude of the ratio between the Cabibbo-suppressed and favored amplitudes, r[subscript B]=0.31 with a one (two) sigma confidence level interval of [0.24, 0.38] ([0.17, 0.43]). The value r[subscript B]=0 is excluded at the 3.3 sigma level. A similar analysis excludes values of γ in the intervals [0, 7]°, [55, 111]°, and [175, 180]° ([85, 99]°) at the one (two) sigma confidence level., United States. Dept. of Energy, National Science Foundation, Natural Sciences and Engineering Research Council of Canada, CNRS/IN2P3 of France, Bundesministerium für Bildung und Forschung, Germany, Istituto Nazionale di Fisica Nucleare of Italy, FOM of the Netherlands, Norges forskningsråd, Ministry of Education and Science of the Russian Federation, MEC (Spain), Science and Technology Facilities Council, United Kingdom

United States. Dept. of Energy, National Science Foundation, Natural Sciences and Engineering Research Council of Canada, CNRS/IN2P3 of France, Bundesministerium für Bildung und Forschung, Germany, Istituto Nazionale di Fisica Nucleare of Italy, FOM of the Netherlands, Norges forskningsråd, Ministry of Education and Science of the Russian Federation, MEC (Spain), Science and Technology Facilities Council, United Kingdom