Showing papers by "D. Su published in 2007"
TL;DR: In this article, the authors measured the cross section for the process e{sup +}e{sup -} {yields} from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at the PEP-II storage rings.
Abstract: The authors measure the cross section for the process e{sup +}e{sup -} {yields} {pi}{sup +}{pi}{sup -}{psi}(2S) from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at the PEP-II e{sup +}e{sup -} storage rings The study is based on 298 fb{sup -1} of data recorded with the BABAR detector A structure is observed in the cross-section not far above threshold, near 432 GeV This structure is not compatible with the Y(4260) previously reported by this experiment A single resonance is adequate to describe the cross-section in the low-energy region (< 57 GeV)
214 citations
TL;DR: In this article, the invariant mass of the hadronic final state defines the effective center-of-mass energy, so that the obtained cross sections from the threshold to about 5 GeV can be compared with corresponding direct \epem measurements.
Abstract: We study the processes $e^+ e^-\to 2(\pi^+\pi^-)\pi^0\gamma$, $2(\pi^+\pi^-)\eta\gamma$, $K^+ K^-\pi^+\pi^-\pi^0\gamma$ and $K^+ K^-\pi^+\pi^-\eta\gamma$ with the hard photon radiated from the initial state. About 20000, 4300, 5500 and 375 fully reconstructed events, respectively, are selected from 232 fb$^{-1}$ of BaBar data. The invariant mass of the hadronic final state defines the effective $e^+ e^-$ center-of-mass energy, so that the obtained cross sections from the threshold to about 5 GeV can be compared with corresponding direct \epem measurements, currently available only for the $\eta\pi^+\pi^-$ and $\omega\pi^+\pi^-$ submodes of the $e^+ e^-\to 2(\pi^+\pi^-)\pi^0$ channel. Studying the structure of these events, we find contributions from a number of intermediate states, and we extract their cross sections where possible. In particular, we isolate the contribution from $e^+ e^-\to\omega(782)\pi^+\pi^-$ and study the $\omega(1420)$ and $\omega(1650)$ resonances. In the charmonium region, we observe the $J/\psi$ in all these final states and several intermediate states, as well as the $\psi(2S)$ in some modes, and we measure the corresponding branching fractions.
151 citations
TL;DR: In this article, the e+e- --> Lambda anti-Lambda gamma, lambda anti-Sigma0 gamma, and Sigma 0 antiSigma 0 gamma processes were studied using 230 fb-1 of integrated luminosity collected by the BABAR detector at an e +e- center-of-mass energy of 10.58 GeV.
Abstract: We study the e+e- --> Lambda anti-Lambda gamma, Lambda anti-Sigma0 gamma, Sigma0 anti-Sigma0 gamma processes using 230 fb-1 of integrated luminosity collected by the BABAR detector at e+e- center-of-mass energy of 10.58 GeV. From the analysis of the baryon-antibaryon mass spectra the cross sections for e+e- --> Lambda anti-Lambda, Lambda anti-Sigma0, Sigma0 anti-Sigma0 are measured in the dibaryon mass range from threshold up to 3 GeV/c^2. The ratio of electric and magnetic form factors, |G_E/G_M|, is measured for e+e- --> Lambda anti-Lambda, and limits on the relative phase between Lambda form factors are obtained. We also measure the J/psi --> Lambda anti-Lambda, Sigma0 anti-Sigma0 and psi(2S) --> Lambda anti-Lambda branching fractions.
108 citations
TL;DR: A search for charmed baryons decaying to D(0)p reveals two states: the Lambdac(2880)+ baryon and a previously unobserved state at a mass of [2939.8+/-1.3(stat)+/- 1.0(syst)] MeV/c2.
Abstract: A search for charmed baryons decaying to $D^0 p$ reveals two states: the $\Lambda_c(2880)^+$ baryon and a previously unobserved state at a mass of [$2939.8\pm 1.3 \text{(stat.)}\pm 1.0 \text{(syst.)}$]~\mevcc and with an intrinsic width of [$17.5\pm 5.2 \text{(stat.)}\pm 5.9 \text{(syst.)}$]~\mev. Consistent and significant signals are observed for the $K^-\pi^+$ and $K^-\pi^+\pi^-\pi^+$ decay modes of the $D^0$ in 287 ${\rm fb}^{-1}$ annihilation data recorded by the BaBar detector at a center-of-mass energy of 10.58~${\rm GeV}/c^2$. There is no evidence in the $D^+ p$ spectrum of doubly-charged partners. The mass and intrinsic width of the $\Lambda_c(2880)^+$ baryon and relative yield of the two baryons are also measured.
104 citations
TL;DR: In this article, the processes e+e-→K+k-π+π-γ, K+K-π0π0γ and K+kπ-K+π+γ, where the photon is radiated from the initial state were studied.
Abstract: We study the processes e+e-→K+K-π+π-γ, K+K-π0π0γ and K+K-K+K-γ, where the photon is radiated from the initial state. About 34600, 4400 and 2300 fully reconstructed events, respectively, are selected from 232fb-1 of BABAR data. The invariant mass of the hadronic final state defines the effective e+e- center-of-mass energy, so that the K+K-π+π-γ data can be compared with direct measurements of the e+e-→K+K-π+π- reaction; no direct measurements exist for the e+e-→K+K-π0π0 or e+e-→K+K-K+K- reactions. Studying the structure of these events, we find contributions from a number of intermediate states, and we extract their cross sections where possible. In particular, we isolate the contribution from e+e-→ (1020)f0(980) and study its structure near threshold. In the charmonium region, we observe the J/ψ in all three final states and several intermediate states, as well as the ψ(2S) in some modes, and measure the corresponding branching fractions. We see no signal for the Y(4260) and obtain an upper limit of BY(4260)→ π+π- •ΓeeY<0.4eV at 90% C.L. © 2007 The American Physical Society.
98 citations
TL;DR: In this paper, the authors present evidence for mixing in colliding-beam data with the BABAR detector at the PEP-II storage rings at the Stanford Linear Accelerator Center.
Abstract: We present evidence for ${D}^{0}\mathrm{\text{\ensuremath{-}}}{\overline{D}}^{0}$ mixing in ${D}^{0}\ensuremath{\rightarrow}{K}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ decays from $384\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of ${e}^{+}{e}^{\ensuremath{-}}$ colliding-beam data recorded near $\sqrt{s}=10.6\text{ }\text{ }\mathrm{GeV}$ with the BABAR detector at the PEP-II storage rings at the Stanford Linear Accelerator Center. We find the mixing parameters ${x}^{\ensuremath{'}2}=[\ensuremath{-}0.22\ifmmode\pm\else\textpm\fi{}0.30(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.21(\mathrm{syst})]\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ and ${y}^{\ensuremath{'}}=[9.7\ifmmode\pm\else\textpm\fi{}4.4(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}3.1(\mathrm{syst})]\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ and a correlation between them of $\ensuremath{-}0.95$. This result is inconsistent with the no-mixing hypothesis with a significance of 3.9 standard deviations. We measure ${R}_{D}$, the ratio of doubly Cabibbo-suppressed to Cabibbo-favored decay rates, to be $[0.303\ifmmode\pm\else\textpm\fi{}0.016(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.010(\mathrm{syst})]%$. We find no evidence for $CP$ violation.
93 citations
TL;DR: In this paper, the cross sections of the baryon-antibaryon mass spectra were obtained from the analysis of the BABAR detector at the center-of-mass energy of 10.58 GeV.
Abstract: We study the ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\mathit{\ensuremath{\Lambda}}\overline{\mathit{\ensuremath{\Lambda}}}\ensuremath{\gamma}$, $\mathit{\ensuremath{\Lambda}}{\overline{\mathit{\ensuremath{\Sigma}}}}^{0}\ensuremath{\gamma}$, ${\mathit{\ensuremath{\Sigma}}}^{0}{\overline{\mathit{\ensuremath{\Sigma}}}}^{0}\ensuremath{\gamma}$ processes using $230\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity collected by the BABAR detector at ${e}^{+}{e}^{\ensuremath{-}}$ center-of-mass energy of 10.58 GeV. From the analysis of the baryon-antibaryon mass spectra the cross sections for ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\mathit{\ensuremath{\Lambda}}\overline{\mathit{\ensuremath{\Lambda}}}$, $\mathit{\ensuremath{\Lambda}}{\overline{\mathit{\ensuremath{\Sigma}}}}^{0}$, ${\mathit{\ensuremath{\Sigma}}}^{0}{\overline{\mathit{\ensuremath{\Sigma}}}}^{0}$ are measured in the dibaryon mass range from threshold up to $3\text{ }\text{ }\mathrm{GeV}/{c}^{2}$. The ratio of electric and magnetic form factors, $|{G}_{E}/{G}_{M}|$, is measured for ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\mathit{\ensuremath{\Lambda}}\overline{\mathit{\ensuremath{\Lambda}}}$, and limits on the relative phase between $\mathit{\ensuremath{\Lambda}}$ form factors are obtained. We also measure the $J/\ensuremath{\psi}\ensuremath{\rightarrow}\mathit{\ensuremath{\Lambda}}\overline{\mathit{\ensuremath{\Lambda}}}$, ${\mathit{\ensuremath{\Sigma}}}^{0}{\overline{\mathit{\ensuremath{\Sigma}}}}^{0}$, and $\ensuremath{\psi}(2S)\ensuremath{\rightarrow}\mathit{\ensuremath{\Lambda}}\overline{\mathit{\ensuremath{\Lambda}}}$ branching fractions.
80 citations
TL;DR: In this paper, a study of exclusive production of the D{bar D} system through initial-state radiation is performed in a search for charmonium states, where D = D{sup 0} or D{Sup +}.
Abstract: A study of exclusive production of the D{bar D} system through initial-state radiation is performed in a search for charmonium states, where D = D{sup 0} or D{sup +}. The D{sup 0} mesons are reconstructed in the D{sup 0} {yields} K{sup -}{pi}{sup +}, D{sup 0} {yields} K{sup -}{pi}{sup +}{pi}{sup 0}, and D{sup 0} {yields} K{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -} decay modes. The D{sup +} is reconstructed through the D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +} decay mode. The analysis makes use of an integrated luminosity of 288.5 fb{sup -1} collected by the BABAR experiment. The D{bar D} mass spectrum shows a clear {psi}(3770) signal. Further structures appear in the 3.9 and 4.1 GeV/c{sup 2} regions. No evidence is found for Y(4260) decays to D{bar D}, implying an upper limit {Beta}(Y(4260) {yields} D{bar D})/{Beta}(Y(4260) {yields} J/{psi}{pi}{sup +}{pi}{sup -}) < 7.6 (95% confidence level).
80 citations
TL;DR: In this article, the branching fractions and CP asymmetries for B{sup 0,yields,pi,sup 0,pi,su,su 0,pi,su,Su,Su 0,Su 1,Su 2,Su 3,Su 4,Su 5,Su 6,Su 7,Su 0,Su 1 ] were measured by the BABAR detector at the PEP-II asymmetric energy B factory at SLAC.
Abstract: We present updated measurements of the branching fractions and CP asymmetries for B{sup 0}{yields}{pi}{sup 0}{pi}{sup 0}, B{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup 0}, and B{sup {+-}}{yields}K{sup {+-}}{pi}{sup 0}. Based on a sample of 383x10{sup 6} {upsilon}(4S){yields}BB decays collected by the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, we measure B(B{sup 0}{yields}{pi}{sup 0}{pi}{sup 0})=(1.47{+-}0.25{+-}0.12)x10{sup -6}, B(B{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup 0})=(5.02{+-}0.46{+-}0.29)x10{sup -6}, and B(B{sup {+-}}{yields}K{sup {+-}}{pi}{sup 0})=(13.6{+-}0.6{+-}0.7)x10{sup -6}. We also measure the CP asymmetries C{sub {pi}{sup 0}}{sub {pi}{sup 0}}=-0.49{+-}0.35{+-}0.05, A{sub {pi}{sup {+-}}}{sub {pi}{sup 0}}=0.03{+-}0.08{+-}0.01, and A{sub K{sup {+-}}}{sub {pi}{sup 0}}=0.030{+-}0.039{+-}0.010. Finally, we present bounds on the Cabibbo-Kobayashi-Maskawa angle {alpha} using isospin relations.
62 citations
TL;DR: A measurement of the tau(-)-> K-pi(0)nu(tau) branching fraction has been made using 230.2 fb(-1) of data recorded by the BABAR detector at the PEP-II e(+)e(-) collider, located at the Stanford Linear Accelerator Center (SLAC), at a center-of-mass energy root s close to 10.58 GeV.
Abstract: A measurement of the tau(-)-> K-pi(0)nu(tau) branching fraction has been made using 230.2 fb(-1) of data recorded by the BABAR detector at the PEP-II e(+)e(-) collider, located at the Stanford Linear Accelerator Center (SLAC), at a center-of-mass energy root s close to 10.58 GeV. We measure B(tau(-)-> K-pi(0)nu(tau))=(0.416 +/- 0.003(stat)+/- 0.018(syst))%.
59 citations
Posted Content•
TL;DR: The International Linear Collider (ILC) is a 200-500 GeV center-of-mass high-luminosity linear electron-positron collider, based on 1.3 GHz superconducting radio-frequency (SCRF) accelerating cavities.
Abstract: The International Linear Collider (ILC) is a 200-500 GeV center-of-mass high-luminosity linear electron-positron collider, based on 1.3 GHz superconducting radio-frequency (SCRF) accelerating cavities. The ILC has a total footprint of about 31 km and is designed for a peak luminosity of 2x10^34 cm^-2 s^-1. The complex includes a polarized electron source, an undulator-based positron source, two 6.7 km circumference damping rings, two-stage bunch compressors, two 11 km long main linacs and a 4.5 km long beam delivery system. This report is Volume III (Accelerator) of the four volume Reference Design Report, which describes the design and cost of the ILC.
TL;DR: In this article, a preliminary measurement of the q2 dependence of the D0 --> K- e+ nu_e decay rate is presented, which is proportional to the hadronic form factor squared, specified by a single parameter.
Abstract: We present a preliminary measurement of the q2 dependence of the D0 --> K- e+ nu_e decay rate. This rate is proportional to the hadronic form factor squared, specified by a single parameter. This is either the mass in the simple pole ansatz m_pole = (1.854 +- 0.016 +- 0.020) GeV/c2 or the scale in the modified pole ansatz alpha_pole = 0.43 +- 0.03 +- 0.04. The first error refers to the statistical, the second to the systematic uncertainty.
TL;DR: The analysis uses events in which the signal B decays are reconstructed with an innovative loose neutrino reconstruction technique, and finds the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element /Vub/ to be (4.4_{FF}) x 10(-3), where the last uncertainty is due to the normalization of the form factor.
Abstract: We report the results of a study of the exclusive charmless semileptonic decay, B-0 ->pi(-)center dot(+)nu, undertaken with approximately 227x10(6) BB pairs collected at the Upsilon(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with an innovative loose neutrino reconstruction technique. We obtain partial branching fractions in 12 bins of q(2), the momentum transfer squared, from which we extract the f(+)(q(2)) form-factor shape and the total branching fraction B(B-0 ->pi(-)l(+)nu)=(1.46 +/- 0.07(stat)+/- 0.08(syst))x10(-4). Based on a recent unquenched lattice QCD calculation of the form factor in the range q(2)> 16 GeV2, we find the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element vertical bar V-ub vertical bar to be (4.1 +/- 0.2(stat)+/- 0.2(syst)+0.6-0.4(FF))x10(-3), where the last uncertainty is due to the normalization of the form factor.
01 Aug 2007
TL;DR: In this paper, an analysis of B0→ρ+ρ- decays using (383.6±4.2)×106 BB pairs collected by the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC is presented.
Abstract: We present results from an analysis of B0→ρ+ρ- decays using (383.6±4.2)×106 BB pairs collected by the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. The measurements of the B0→ρ+ρ- branching fraction, longitudinal polarization fraction fL, and the CP-violating parameters Slong and Clong are as follows: B(B0→ρ+ρ-)=(25.5±2.1(stat)-3.9+3.6(syst))×10-6, fL=0.992±0.024(stat)-0.013+0.026(syst), Slong=-0.17±0.20(stat)-0. 06+0.05(syst), Clong=0.01±0.15(stat)±0.06(syst). We determine the unitarity triangle angle α, using an isospin analysis of B→ρρ decays. One of the two solutions, α=[73.1,117.0]° at 68% confidence level, is compatible with standard model-based fits of existing data. Constraints on the unitarity triangle are also evaluated using an SU(3) symmetry-based approach. © 2007 The American Physical Society.
TL;DR: A search for neutrinoless, lepton-flavor violating decay of the tau lepton into three charged leptons has been performed using 376 fb^{-1} of data collected at an e^+e^- center-of-mass energy around 10.58 GeV with the BaBar detector at the PEP-II storage rings as discussed by the authors.
Abstract: A search for the neutrinoless, lepton-flavor violating decay of the tau lepton into three charged leptons has been performed using 376 fb^{-1} of data collected at an e^+e^- center-of-mass energy around 10.58 GeV with the BaBar detector at the PEP-II storage rings. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (4-8) x 10^{-8} at 90% confidence level.
TL;DR: A search for lepton flavor violating decays of the tau lepton to a lighter mass lepton and a pseudoscalar meson has been performed using data collected at a center-of-mass energy near 10.58 GeV by the BABAR detector at the SLAC PEP-II storage ring.
Abstract: A search for lepton flavor violating decays of the tau lepton to a lighter mass lepton and a pseudoscalar meson has been performed using 339 fb(-1) of e(+)e(-) annihilation data collected at a center-of-mass energy near 10.58 GeV by the BABAR detector at the SLAC PEP-II storage ring. No evidence of a signal has been found, and upper limits on the branching fractions are set at the 10(-7) level.
TL;DR: In this article, the amplitudes of B→ψ(2S)K* and Bχc1K* were measured using the BABAR detector at the PEP-II storage ring, corresponding to 232×106 BB pairs.
Abstract: We perform the first three-dimensional measurement of the amplitudes of B→ψ(2S)K* and B→χc1K* decays and update our previous measurement for B→J/ψK*. We use a data sample collected with the BABAR detector at the PEP-II storage ring, corresponding to 232×106 BB pairs. The longitudinal polarization of decays involving a JPC=1++ χc1 meson is found to be larger than that with a 1 - J/ψ or ψ(2S) meson. No direct CP-violating charge asymmetry is observed. © 2007 The American Physical Society.
TL;DR: In this paper, the authors present updated measurements of CP-violating asymmetries in the decays B0→D*±D and B 0→D+D- using (383±4) ×106BB pairs collected by the BABAR detector at the SLAC PEP-II B factory.
Abstract: We present updated measurements of CP-violating asymmetries in the decays B0→D*±D and B0→D+D- using (383±4) ×106BB pairs collected by the BABAR detector at the SLAC PEP-II B factory. We determine the time-integrated CP asymmetry AD*±D=0. 12±0.06±0.02, and the time-dependent asymmetry parameters to be CD*+D-=0.18±0.15±0.04, SD*+D-=-0.79±0. 21±0.06, CD*-D+=0.23±0.15±0.04, SD*-D+=-0. 44±0.22±0.06, CD+D-=0.11±0.22±0.07, and SD+D-=-0.54±0.34±0.06, where the first uncertainty is statistical and the second is systematic. © 2007 The American Physical Society.
TL;DR: In this paper, the authors present measurements of the branching fractions for the charmless two-body decays B0→π+π-nγ, and a search for the decay B 0→K+K-.
Abstract: We present measurements of the branching fractions for the charmless two-body decays B0→π+π- and B0→K+π-, and a search for the decay B0→K+K-. We include the effects of final-state radiation from the daughter mesons for the first time, and quote branching fractions for the inclusive processes B0→h+h′-nγ, where h and h′ are pions or kaons. The maximum value of the sum of the energies of the n undetected photons, Eγmax, is mode-dependent. Using a data sample of approximately 227×106 Υ(4S)→BB decays collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we measure: B(B0→π+π-nγ;Eγmax =150MeV)=(5.1±0.4±0.2) ×10-6, B(B0→K+π-nγ;Eγmax =105MeV)=(18.1±0. 6±0.6)×10-6, B(B0→K+K-nγ;Eγmax =59MeV)<0.5×10-6(90%confidence level), where the first uncertainty is statistical and the second is systematic. Theoretical calculations can be used to extrapolate from the above measurements the nonradiative branching fractions, B0. Using one such calculation, we find: B0(B0→π+π-)=(5.5±0. 4±0.3)×10-6, B0(B0→K+π-)=(19.1±0.6±0.6) ×10-6, B0(B0→K+K-)<0.5×10-6(90%confidence level). Meaningful comparison between theory and experiment, as well as combination of measurements from different experiments, can be performed only in terms of these nonradiative quantities. © 2007 The American Physical Society.
TL;DR: In this paper, the BABAR detector collected 230.2 fb^(-1) of e+e- annihilation data collected at and near the peak of the Y(4S) resonance, 489 +/- 55 events containing the pure leptonic decay D_s^+ --> mu^+ nu_mu have been isolated in charm-tagged events.
Abstract: Using 230.2 fb^(-1) of e+e- annihilation data collected with the BABAR detector at and near the peak of the Y(4S) resonance, 489 +/- 55 events containing the pure leptonic decay D_s^+ --> mu^+ nu_mu have been isolated in charm-tagged events. The ratio of partial widths Gamma(D_s^+ --> mu^+ nu_mu)/Gamma(D_s^+ --> phi pi^+) is measured to be 0.143 +/- 0.018 +/- 0.006 allowing a determination of the pseudoscalar decay constant f_{D_s} = (283 +/- 17 +/- 7 +/- 14) MeV. The errors are statistical, systematic, and from the D_s^+ --> phi pi^+ branching ratio, respectively.
TL;DR: In this article, the authors search for D0-D0 mixing in D*+→π+D0 decays with D0→K(*)eν in a sample of e+e-→cc events produced near 10.58 GeV.
Abstract: We have searched for D0-D0 mixing in D*+→π+D0 decays with D0→K(*)eν in a sample of e+e-→cc events produced near 10.58 GeV. The charge of the slow pion from charged D* decay tags the charm flavor at production, and it is required to be consistent with the flavor of a fully reconstructed second charm decay in the same event. We observe 3 mixed candidates compared to 2.85 background events expected from simulation. We ascribe a 50% systematic uncertainty to this expected background rate. We find a central value for the mixing rate of 0.4×10-4. Using a frequentist method, we set corresponding 68% and 90% confidence intervals at (-5.6,7.4)×10-4 and (-13,12)×10-4, respectively. © 2007 The American Physical Society.
TL;DR: The direct CP asymmetry to be consistent with zero is found and a broad structure peaking near 1.5 GeV/c{2} in the K+K- invariant mass distribution is found.
Abstract: We report the observation of charmless hadronic decays of charged B mesons to the final state K+K-pi+. Using a data sample of 347.5 fb^-1 collected at the Y(4S) resonance with the BABAR detector, we observe 429+/-43 signal events with a significance of 9.6 sigma. We measure the inclusive branching fraction BF(B+ --> K+K-pi+) = [5.0+/-0.5(stat.)+/-0.5(syst.)]x10^-6. Inspection of the Dalitz plot of signal candidates shows a broad structure peaking near 1.5 GeV/c^2 in the K+K- invariant mass distribution. We find the direct CP asymmetry to be consistent with zero.
TL;DR: In this article, the decays of B mesons to ppbarh final states, where h=pi+, Ks, K*0 or K*+, were studied with a sample of 232x10^6 Upsilon(4S)->BBbar events collected with the BaBar detector.
Abstract: With a sample of 232x10^6 Upsilon(4S)->BBbar events collected with the BaBar detector, we study the decays of B mesons to ppbarh final states, where h=pi+,Ks,K*0 or K*+. We report evidence for the B->ppbarK*0 decay, with a branching fraction (1.5+/-0.5(stat)+/-0.4(syst))x10^-6, and for the B+->eta_cK*+ decay, with the branching fraction of Br(B+->eta_cK*+)xBr(eta_c->ppbar)=(1.57^{+0.56}_{-0.45}(stat)^{+0.46}_{-0.36}(syst))x10^-6, and provide improved measurements of the branching fractions of the other modes of this type. We also report the measurements of the charge asymmetry consistent with zero in the B+->ppbarpi+, B0->ppbarK*0 and B+->ppbarK*+ modes. No evidence is found for the pentaquark candidate Theta+ in the mass range 1.52 to 1.55 GeV/c^2, decaying into pKs, or the glueball candidate fJ(2220) in the mass range 2.2
TL;DR: In this article, the amplitudes of the singly Cabibbo-suppressed decay D^0 --> K^- K^+ pi 0.5 +/- 1.9 (stat) +/- 2.2 (syst) degrees were measured.
Abstract: Using 385 fb^-1 of e^+e^- collisions at the CM energies of around 10.6 GeV recorded by the BaBar experiment, we study the amplitudes of the singly Cabibbo-suppressed decay D^0 --> K^- K^+ pi^0. We measure the strong phase difference between the D0bar and D0 decays to the K^*(892)^+ K^- state to be -35.5 +/- 1.9 (stat) +/- 2.2 (syst) degrees, and their amplitude ratio to be 0.599 +/- 0.013 (stat) +/- 0.011 (syst). We observe significant contributions from the Kpi and K^-K^+ scalar and vector amplitudes, and analyze the moments of the cosine of the helicity angle in these systems. We find no evidence for charged, scalar kappa(800) state, nor for higher spin states. We also perform a model-independent partial wave analysis of the K^-K^+ system in a limited mass range around 1 GeV/c^2. We study several models for Kpi S-wave amplitude, and describe which one is favored by our data.
TL;DR: In this article, the authors performed a search for the flavor-changing neutral-current decays B→π + -, where + - is either e+e- or μ+μ-, using a sample of 230×106 Υ(4S)→BB decays collected with the BABAR detector.
Abstract: We have performed a search for the flavor-changing neutral-current decays B→π + -, where + - is either e+e- or μ+μ-, using a sample of 230×106 Υ(4S)→BB decays collected with the BABAR detector. We observe no evidence of a signal and measure the upper limit on the isospin-averaged branching fraction to be B(B→π + -)<9.1×10-8 at 90 confidence level. We also search for the lepton-flavor-violating decays B→πe±μ and measure an upper limit on the isospin-averaged branching fraction of B(B→πe±μ )<9.2×10-8 at 90 confidence level. © 2007 The American Physical Society.
TL;DR: In this paper, a CP violation analysis of the decay B-+/- -> D pi+pi(-)pi K-0(+/-) branching fraction and decay rate asymmetry is presented.
Abstract: We report the results of a CP violation analysis of the decay B-+/- -> D pi+pi(-)pi K-0(+/-), where D-pi(+)pi(-)pi(0) indicates a neutral D meson detected in the final state pi(+)pi(-)pi(0), excluding K-S(0)pi(0). The analysis makes use of 324x10(6) e(+)e -> B (B) over bar events recorded by the BABAR experiment at the PEP-II e(+)e(-) storage ring. Analyzing the pi(+)pi(-)pi(0) Dalitz plot distribution and the B-+/- -> D-pi(+)pi(-)pi K-0(+/-) branching fraction and decay rate asymmetry, we find the following one-standard-deviation constraints on the amplitude ratio and on the weak and strong phases: 0.06 pi(+)pi(-)pi(0) decay amplitude.
TL;DR: In this paper, the amplitude analysis of the decays B(0)->phiK(2)(1430)(0), phiK*(892)-0, and phi(Kpi)(0)(S-wave) with a sample of about 384x10(6) BB[over ] pairs recorded with the BABAR detector is performed.
Abstract: We perform an amplitude analysis of the decays B(0)-->phiK*(2)(1430)(0), phiK*(892)(0), and phi(Kpi)(0)(S-wave) with a sample of about 384x10(6) BB[over ] pairs recorded with the BABAR detector. The fractions of longitudinal polarization f(L) of the vector-tensor and vector-vector decay modes are measured to be 0.853(-0.069+0.061)+/-0.036 and 0.506+/-0.040+/-0.015, respectively. Overall, twelve parameters are measured for the vector-vector decay and seven parameters for the vector-tensor decay, including the branching fractions and parameters sensitive to CP violation.
TL;DR: In this article, the total production rates and momentum distributions of the charmed baryon Lambda(+)(c) in e(+)e(-)-> hadrons at a center-of-mass energy of 10.54 GeV and in Upsilon(4S) decays were measured.
Abstract: We present measurements of the total production rates and momentum distributions of the charmed baryon Lambda(+)(c) in e(+)e(-)-> hadrons at a center-of-mass energy of 10.54 GeV and in Upsilon(4S) decays. In hadronic events at 10.54 GeV, charmed hadrons are almost exclusively leading particles in e(+)e(-)-> cc events, allowing direct studies of c-quark fragmentation. We measure a momentum distribution for Lambda(+)(c) baryons that differs significantly from those measured previously for charmed mesons. Comparing with a number of models, we find none that can describe the distribution completely. We measure an average scaled momentum of =0.574 +/- 0.009 and a total rate of N-Lambda c(qq)=0.057 +/- 0.002(exp.)+/- 0.015(BF) Lambda(+)(c) per hadronic event, where the experimental error is much smaller than that due to the branching fraction into the reconstructed decay mode, pK(-)pi(+). In Upsilon(4S) decays we measure a total rate of N-Lambda c(Upsilon)=0.091 +/- 0.006(exp.)+/- 0.024(BF) per Upsilon(4S) decay, and find a much softer momentum distribution than expected from B decays into a Lambda(+)(c) plus an antinucleon and one to three pions.
TL;DR: In this paper, a measurement of CP-violating asymmetries in B-0 meson over bar decays using a time-dependent Dalitz plot analysis is reported.
Abstract: We report a measurement of CP-violating asymmetries in B-0 ->(rho pi)(0)->pi(+)pi(-)pi(0) decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 375x10(6) Upsilon(4S)-> B (B) over bar 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-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.