Prevalence of Community-Associated Methicillin-Resistant Staphylococcus aureus in Patients with Cystic Fibrosis

We prospectively determined the prevalence of community-associated Staphylococcus aureus in a large cystic fibrosis (CF) center between October 2005 and October 2007. We found that 2.7% (19/707) of the CF patients who had cultures during the study period were infected with this organism, representing 14% of the total methicillin-resistant Staphylococcus aureus strains (n = 140) recovered from the patient population during the study period

Evidence for direct CP violation in the decay B->D(*)K, D->KsPi+Pi- and measurement of the CKM phase phi3

We present a new measurement of the unitarity triangle angle phi3 using a Dalitz plot analysis of the KsPi+Pi- decay of the neutral D meson produced in B->D(*)K decays. The method exploits the interference between D0 and D0bar to extract the angle phi3, strong phase delta and the ratio r of suppressed and allowed amplitudes. We apply this method to a 605 fb-1 data sample collected by the Belle experiment. The analysis uses three decays: B->DK, and B->D*K with D*->DPi0 and D*->Dgamma, as well as the corresponding charge-conjugate modes. From a combined maximum likelihood fit to the three modes, we obtain phi3 = 78.4^+10.8_-11.6 +- 3.6 (syst) +- 8.9 (model) degrees. CP conservation in this process is ruled out at the confidence level (1-CL)=5x10^-4, or 3.5 standard deviations.Comment: 10 pages, 5 figures, 4 tables. Replaced by version published in Phys. Rev.

Search for the X(1812) in B±→K±ωϕB^{\pm} \to K^{\pm} \omega \phi

We report on a search for the X(1812) state in the decay $B^{\pm} \to K^{\pm} \omega \phi$ with a data sample of $657\times10^6$ $B\bar{B}$ pairs collected with the Belle detector at the KEKB $e^+e^-$ collider. No significant signal is observed. An upper limit ${\cal B}(B^{\pm} \to K^{\pm} X(1812),X(1812) \to \omega \phi)<3.2\times 10^{-7}$ (90% C.L.) is determined. We also constrain the three-body decay branching fraction to be ${\cal B}(B^{\pm} \to K^{\pm} \omega \phi)$ $<$ 1.9 $\times 10^{-6}$ (90% C.L.).Comment: 5pages,2 figures(3 figure files). submitted to PRD(RC

Evidence for B to K eta' gamma Decays at Belle

We present the results of a search for the radiative decay (B -> K eta' gamma) and find evidence for (B^+ -> K^+ eta' gamma) decays at the 3.3 standard deviation level with a partial branching fraction of (3.6 +/- 1.2 +/- 0.4) x 10e-6, where the first error is statistical and the second systematic. This measurement is restricted to the region of combined (K eta') invariant mass less than 3.4GeVc^2. A 90% confidence level upper limit of 6.4 x 10e-6 is obtained for the decay (B^0 -> K^0 eta' gamma) in the same (K eta') invariant mass region. These results are obtained from a 605 fb^-1 data sample containing 657 x 10e6 B anti-B pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^+e^- collider.Comment: 5 pages, 4 figures. Submitted to PRD-RC on 6/8/0

Measurements of Charmless Hadronic b->s Penguin Decays in the pi+pi-K+pi- Final State and First Observation of B0 -> rho0K+pi-

We report measurements of charmless hadronic B^0 decays into the pi+pi-K+pi+ final state. The analysis uses a sample of 657x10^6 BBbar pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider at the Y(4S) resonance. The decay B^0 -> rho0 Kpi is observed for the first time; the significance is 5.0sigma and the corresponding partial branching fraction for M_Kpi in (0.75,1.20) GeV/c^2 is [2.8 +- 0.5(stat) +-0.5(syst)] x 10^{-6}. We also obtain the first evidence for B^0 -> f0Kpi with 3.5sigma significance and for B^0 -> pi+pi-K*0 with 4.5sigma significance. For the two-body decays B^0 -> rho0K*0 and B^0 -> f0K*0, the significances are 2.7sigma and 2.5sigma, respectively, and the upper limits on the branching fractions are 3.4x10^{-6} and 2.2x10^{-6} at 90% confidence level.Comment: 6 pages, 3 figures. accepted by PRD(RC

Observation of Bs->Ds(*)+Ds(*)- using e+e- collisions and a determination of the Bs-Bsbar width difference \Delta\Gamma_s

We have made the first observation of Bs->Ds(*)+Ds(*)- decays using 23.6 fb-1 of data recorded by the Belle experiment running on the Upsilon(5S) resonance. The branching fractions are measured to be B(B^0_s\ra D^+_s D^-_s) = (1.0\,^{+0.4}_{-0.3}\,^{+0.3}_{-0.2})%, B(B^0_s\ra D^{*\pm}_s D^{\mp}_s) = (2.8\,^{+0.8}_{-0.7}\,\pm 0.7)%, and B(B^0_s\ra D^{*+}_s D^{*-}_s) = (3.1\,^{+1.2}_{-1.0}\,\pm 0.8)%; the sum is B(B^0_s\ra D^{(*)+}_s D^{(*)-}_s) = (6.9\,^{+1.5}_{-1.3}\,\pm 1.9)%. Assuming Bs->Ds(*)+Ds(*)- saturates decays to CP-even final states, the branching fraction determines the ratio \Delta\Gamma_s/cos(\phi), where \Delta\Gamma_s is the difference in widths between the two Bs-Bsbar mass eigenstates, and \phi is a CP-violating weak phase. Taking CP violation to be negligibly small, we obtain \Delta\Gamma_s/\Gamma_s = 0.147^{+0.036}_{-0.030}(stat.)^{+0.044}_{-0.042}(syst.), where \Gamma_s is the mean decay width.Comment: 13 pages, 2 figures, 2 tables. v2: text added for clarification, version published in Phys. Rev. Letter

Time-Dependent CP Asymmetries in B0 -> Ks pi0 gamma transitions

We report measurements of CP violation parameters in B0->Ks pi0 gamma transitions based on a data sample of 535x10^6 BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. One neutral B meson is fully reconstructed in the B0->Ks pi0 gamma mode. The flavor of the accompanying B meson is identified from its decay products. For a Ks pi0 invariant mass up to 1.8 GeV/c^2, we obtain S = -0.10 +- 0.31 +- 0.07 and A = -0.20 +- 0.20 +- 0.06. For a Ks pi0 invariant mass near the K*0(892) resonance, we obtain S = -0.32 +0.36-0.33 +-0.05 and A=-0.20 +-0.24 +-0.05.Comment: 6 pages, 3 figures, accepted by PR

Measurement Of |V_ub| From Inclusive Charmless Semileptonic B Decays

We present the partial branching fraction for inclusive charmless semileptonic B decays and the corresponding value of the CKM matrix element |Vub|, using a multivariate analysis method to access ~90% of the B -> Xu l nu phase space. This approach dramatically reduces the theoretical uncertainties from the b-quark mass and non-perturbative QCD compared to all previous inclusive measurements. The results are based on a sample of 657 million B -Bbar pairs collected with the Belle detector. We find that Delta BR(B -> Xu l nu; p^*B_l>1.0 GeV/c=1.963 x (1 +/- 0.088(stat.) +/- 0.081(sys.)) x 10^-3. Corresponding values of |Vub| are extracted using several theoretical calculations.Comment: 9 pages, 1 figure, 2 tables. Published in PR

Improved Measurements of Branching Fractions and CP Asymmetries in B-> eta h Decays

We report improved measurements of B decays with an eta meson in the final state using 492 fb^{-1} of data collected by the Belle detector at the KEKB e^+ e^- collider. We observe the decays B^{+-}-> eta pi^{+-} and B^{+-}-> eta K^{+-}; the measured branching fractions are Br(B^{+-}-> eta pi^{+-}) = (4.2+- 0.4(stat)+- 0.2(sys))x10^{-6} and Br(B^{+-}-> eta K^{+-}) = (1.9+-0.3(stat)^{+0.2}_{-0.1}(sys))x10^{-6}. The corresponding CP-violating asymmetries are measured to be -0.23+- 0.09(stat) +-0.02(sys) for eta pi^{+-} and -0.39+-0.16(stat)+-0.03(sys) for eta K^{+-}. We also search for B^0-> eta K^0 decays and set an upper limit of 1.9x10^{-6} at the 90% confidence level.Comment: 7 pages, 3 figure