Differential branching fraction and angular analysis of the decay B0→K∗0μ+μ−

The angular distribution and differential branching fraction of the decay B 0→ K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions

Measurement of the CP-violating phase phi_s in the decay Bs->J/psi phi

We present a measurement of the time-dependent CP-violating asymmetry in B_s -> J/psi phi decays, using data collected with the LHCb detector at the LHC. The decay time distribution of B_s -> J/psi phi is characterized by the decay widths Gamma_H and Gamma_L of the heavy and light mass eigenstates of the B_s-B_s-bar system and by a CP-violating phase phi_s. In a sample of about 8500 B_s -> J/psi phi events isolated from 0.37 fb^-1 of pp collisions at sqrt(s)=7 TeV we measure phi_s = 0.15 +/- 0.18 (stat) +/- 0.06 (syst) rad. We also find an average B_s decay width Gamma_s == (Gamma_L + Gamma_H)/2 = 0.657 +/- 0.009 (stat) +/- 0.008 (syst) ps^-1 and a decay width difference Delta Gamma_s == Gamma_L - Gamma_H} = 0.123 +/- 0.029 (stat) +/- 0.011 (syst) ps^-1. Our measurement is insensitive to the transformation (phi_s,DeltaGamma_s --> pi - phi_s, - Delta Gamma_s.Comment: 9 pages, 3 figure

Measurements of the branching fractions of the decays B°s → D∓s K± and B°s → D¯sπ+

The decay mode B°s → D∓s K± allows for one of the theoretically cleanest measurements of the CKM angle γ through the study of time-dependent CP violation. This paper reports a measurement of its branching fraction relative to the Cabibbo-favoured mode B°s → D¯sπ+ based on a data sample corresponding to 0.37 fb¯¹ of proton-proton collisions at √s = 7TeV collected in 2011 with the LHCb detector. In addition, the ratio of B meson production fractions fs/fd, determined from semileptonic decays, together with the known branching fraction of the control channel B°s → D¯sπ+ is used to perform an absolute measurement of the branching fractions: B(B°s → D¯sπ+) = (2.95 ± 0.05 ± 0.17 -0.22 +0.18) × 10¯³ ; B(B°s → D∓s K±) = (1.90 ± 0.12 ± 0.13 -0.14 +0.12) × 10¯4 ; where the first uncertainty is statistical, the second the experimental systematic uncertainty, and the third the uncertainty due to f s/f

Strong constraints on the rare decays Bs -> mu+ mu- and B0 -> mu+ mu-

A search for Bs -> mu+ mu- and B0 -> mu+ mu- decays is performed using 1.0 fb^-1 of pp collision data collected at \sqrt{s}=7 TeV with the LHCb experiment at the Large Hadron Collider. For both decays the number of observed events is consistent with expectation from background and Standard Model signal predictions. Upper limits on the branching fractions are determined to be BR(Bs -> mu+ mu-) mu+ mu-) < 1.0 (0.81) x 10^-9 at 95% (90%) confidence level.Comment: 2+6 pages; 4 figures; Accepted for publication in Physical Review Letter

Observation of the decay Bc→J/ψK+K−π+B_c \rightarrow J/\psi K^+ K^- \pi^+

The decay $B_c\rightarrow J/\psi K^+ K^- \pi^+$ is observed for the first time, using proton-proton collisions collected with the LHCb detector corresponding to an integrated luminosity of 3fb$^{-1}$. A signal yield of $78\pm14$ decays is reported with a significance of 6.2 standard deviations. The ratio of the branching fraction of \B_c \rightarrow J/\psi K^+ K^- \pi^+ decays to that of $B_c \rightarrow J/\psi \pi^+$ decays is measured to be $0.53\pm 0.10\pm0.05$, where the first uncertainty is statistical and the second is systematic.Comment: 18 pages, 2 figure

Coartem®: the journey to the clinic

Artemisinin, from which the artemether component of Coartem®(artemether/lumefantrine, AL) is derived, is obtained from the plant sweet wormwood (Artemisia annua) which has been used for over 2,000 years as a Chinese herbal remedy. Artemisinin was first identified by Chinese researchers as the active anti-malarial constituent of A. annua and its derivatives were found to be the most potent of all anti-malarial drugs. Artemether acts rapidly, reducing the infecting parasite biomass by approximately 10,000-fold per asexual life cycle. Lumefantrine, the other active constituent of AL, acts over a longer period to eliminate the residual 100-100,000 parasites that remain after artemether is cleared from the body and thus minimizes the risk of recrudescence. The two agents have different modes of action and act at different points in the parasite life cycle and show a synergistic action against Plasmodium falciparum in vitro. The combination of artemether and lumefantrine reduces the risk of resistance developing to either agent, and to date there are no reports of resistance to AL combined therapy in the malaria parasite that infects humans. Following a unique partnership agreement between Chinese authorities and Novartis, the manufacturer of AL, over 20 sponsored clinical studies have been undertaken in various malaria endemic regions and in travellers. These trials have involved more than 3,500 patients (including over 2,000 children), and led to identification of a six-dose, three-day regimen as the optimal dosing strategy for AL in uncomplicated falciparum malaria. AL has consistently shown 28-day polymerase chain (PCR)-corrected cure rates greater than 95% in the evaluable population, meeting WHO recommendations. More recently, Novartis and the Medicines for Malaria Venture have worked in partnership to develop Coartem® Dispersible, a new formulation designed specifically to meet the specific needs of children with malaria. The dispersible tablets have shown similar high response rates to those observed with crushed standard tablets of AL. A partnership agreement between Novartis and WHO has seen over 250 million AL (Coartem®) treatments (75% for children) being distributed to malaria patients in developing countries without profit, supported by training programmes and educational resources