A search for charmless three-body decays of B0 and B0s mesons with a KS0 meson in the final state is performed using the pp collision data, corresponding to an integrated luminosity of 1.0 /fb, ...collected at a centre-of-mass energy of 7 TeV recorded by the LHCb experiment. Branching fractions of the B0(s) -> KS0 h+ h'- decay modes (h(') = \pi, K), relative to the well measured B0 -> KS0 \pi+ \pi- decay, are obtained. First observation of the decay modes B0s -> KS0 K+/- \pi-/+ and B0s -> KS0 \pi+ \pi- and confirmation of the decay B0 -> KS0 K+/- \pi-/+ are reported. The following relative branching fraction measurements or limits are obtained BF(B0 -> KS0 K+/- \pi-/+) / BF(B0 -> KS0 \pi+ \pi-) = 0.128 +/- 0.017 (stat.) +/- 0.009 (syst.), BF(B0 -> KS0 K+ K-) / BF(B0 -> KS0 \pi+ \pi-) = 0.385 +/- 0.031 (stat.) +/- 0.023 (syst.), BF(B0s -> KS0 \pi+ \pi-) / BF(B0 -> KS0 \pi+ \pi-) = 0.29 \pm 0.06 (stat.) +/- 0.03 (syst.) +/- 0.02 (f_s/f_d), BF(B0s -> KS0 K+/- \pi-/+) / BF(B0 -> KS0 \pi+ \pi-) = 1.48 +/- 0.12 (stat.) +/- 0.08 (syst.) +/- 0.12 (f_s/f_d), BF(B0s -> KS0 K+ K-) / BF(B0 -> KS0 \pi+ \pi-) E 0.004;0.068 at 90% CL.
A study of $D^+\pi^-$, $D^0 \pi^+$ and $D^{*+}\pi^-$ final states is performed using pp collision data, corresponding to an integrated luminosity of 1.0 $fb^{-1}$, collected at a centre-of-mass ...energy of 7 TeV with the LHCb detector. The $D_1(2420)^0$ resonance is observed in the $D^{*+}\pi^-$ final state and the $D^*_2(2460)$ resonance is observed in the $D^+\pi^-$, $D^0 \pi^+$ and $D^{*+}\pi^-$ final states. For both resonances, their properties and spin-parity assignments are obtained. In addition, two natural parity and two unnatural parity resonances are observed in the mass region between 2500 and 2800 MeV. Further structures in the region around 3000 MeV are observed in all the $D^{*+}\pi^-$, $D^+\pi^-$ and $D^0 \pi^+$ final states.
The results of searches for B0(s) -> J/{\psi} p pbar and B+ -> J/{\psi} p pbar {\pi}+ decays are reported. The analysis is based on a data sample, corresponding to an integrated luminosity of 1.0 ...fb^-1 of pp collisions, collected with the LHCb detector. An excess with 2.8 {\sigma} significance is seen for the decay B0s -> J/{\psi} p pbar and an upper limit on the branching fraction is set at the 90 % confidence level: B(B0s -> J/{\psi} p pbar) < 4.8 x 10^-6, which is the first such limit. No significant signals are seen for B0 -> J/{\psi} p pbar and B+ -> J/{\psi} p pbar {\pi}+ decays, for which the corresponding limits are set: B(B0 -> J/{\psi} p pbar) < 5.2 x 10^-7, which significantly improves the existing limit; and B(B+ -> J/{\psi} p pbar {\pi}+) < 5.0 x 10^-7, which is the first limit on this branching fraction.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).The suppressed decay Lambda sub( )b super(0) arrow right p pi super(-) mu super(+) mu super(-), excluding the J/ psi and ...psi (2S) arrow right mu super(+) mu super(-) resonances, is observed for the first time with a significance of 5.5 standard deviations. The analysis is performed with proton-proton collision data corresponding to an integrated luminosity of 3 fb super(-1) collected with the LHCb experiment. The Lambda sub( )b super(0) arrow right p pi super(-) mu super(+) mu super(-) branching fraction is measured relative to the Lambda sub( )b super(0) arrow right J/ psi ( arrow right mu super(+) mu super(-))p pi super(-) branching fraction giving ... ... where the first uncertainty is statistical and the second is systematic. This is the first observation of a b arrow right d transition in a baryonic decay. Figure not available: see fulltext.
A key ingredient to searches for physics beyond the Standard Model in $B^{0}_{s}$ mixing phenomena is the measurement of the $B^{0}_{s}$-$\bar{B}^{0}_{s}$ oscillation frequency, which is equivalent ...to the mass difference $\Delta m_{s}$ of the $B^{0}_{s}$ mass eigenstates. Using the world's largest $B^{0}_{s}$ meson sample accumulated in a dataset, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, collected by the LHCb experiment at the CERN LHC in 2011, a measurement of $\Delta m_{s}$ is presented. A total of about 34,000 $B^{0}_{s}\rightarrowD^{-}_{s}\pi^{+}$ signal decays are reconstructed, with an average decay time resolution of 44 fs. The oscillation frequency is measured to be \mbox{$\Delta m_{s}$ = 17.768 $\pm$ 0.023 (stat) $\pm$ 0.006 (syst) ps$^{-1}$}, which is the most precise measurement to date.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).The ratio of branching fractions and the difference in CP asymmetries of the decays B super(+) arrow right J/ psi pi ...super(+) and B super(+) arrow right J/ psi K super(+) are measured using a data sample of pp collisions collected by the LHCb experiment, corresponding to an integrated luminosity of 3 fb super(-1) at centre-of-mass energies of 7 and 8 TeV. The results are ... ... ... ... where the first uncertainties are statistical and the second are systematic. Combining this result with a recent LHCb measurement of ... provides the most precise estimate to date of CP violation in the decay B super(+) arrow right J/ psi pi super(+), ... ...Figure not available: see fulltext.
Abstract Two new algorithms for use in the analysis of $$pp$$ p p collision are developed to identify the flavour of $${\mathrm {B}} ^0$$ B 0 mesons at production using pions and protons from the ...hadronization process. The algorithms are optimized and calibrated on data, using $${{\mathrm {B}} ^0} \!\rightarrow D^{-}\pi ^{+}$$ B 0 → D - π + decays from $$pp$$ p p collision data collected by LHCb at centre-of-mass energies of 7 and 8 TeV . The tagging power of the new pion algorithm is 60% greater than the previously available one; the algorithm using protons to identify the flavour of a $${\mathrm {B}} ^0$$ B 0 meson is the first of its kind.
The angular distributions and the partial branching fraction of the decay $B^{0} \rightarrow K^{*0} \mu^+ \mu^-$ are studied using an integrated luminosity of $0.37\,fb^{-1}$ of data collected with ...the LHCb detector. The forward-backward asymmetry of the muons, $A_{\mathrm{FB}}$, the fraction of longitudinal polarisation, $F_{\mathrm{L}}$, and the partial branching fraction, $\mathrm{d}{\mathcal B}/\mathrm{d}q^{2}$, are determined as a function of the dimuon invariant mass. The measurements are in good agreement with the Standard Model predictions and are the most precise to date. In the dimuon invariant mass squared range $1.00-6.00{\mathrm{\,Ge\kern -0.1em V}}^2/c^4$, the results are $A_{\mathrm{FB}}=-0.06\,^{+0.13}_{-0.14} \pm 0.04$, $F_{\mathrm{L}}=0.55\pm 0.10\pm 0.03$ and $\mathrm{d}{\mathcal B}/\mathrm{d}q^{2}=(0.42 \pm 0.06\pm 0.03) \times 10^{-7}c^4/{\mathrm{\,Ge\kern -0.1em V}}^2$. In each case, the first error is statistical and the second systematic.
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-) < 4.5 (3.8) x 10^-9 and BR(B0 -> mu+ mu-) < 1.0 (0.81) x 10^-9 at 95% (90%) confidence level.
First observations of the Cabibbo suppressed decays B0bar -->D+ K- pi+ pi- and B- --> D0 K- pi+ pi- are reported using 35 pb^{-1} of data collected with the LHCb detector. Their branching fractions ...are measured with respect to the corresponding Cabibbo favored decays, from which we obtain B(B0bar --> D+ K- pi+ pi-)/B(B0bar --> D+ pi- pi+ pi-)=(5.9\pm1.1\pm0.5) x 10^{-2} and B(B- --> D0 K- pi+ pi-)/B(B- --> D0 pi- pi+ pi-)=(9.4\pm1.3\pm0.9) x 10^{-2}, where the uncertainties are statistical and systematic, respectively. The B- --> D0 K- pi+ pi- decay is particularly interesting, as it can be used in a similar way to B- --> D0 K- to measure the CKM phase gamma.
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