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.
(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.
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.
Measurements of the differential branching fraction and angular moments of the decay B super(0) arrow right K super(+) pi super(-) mu super(+) mu super(-) in the K super(+) pi super(-) invariant mass ...range 1330 < m(K super(+) pi super(-)) < 1530 MeV/c super(2) are presented. Proton-proton collision data are used, corresponding to an integrated luminosity of 3 fb super(-1) collected by the LHCb experiment. Differential branching fraction measurements are reported in five bins of the invariant mass squared of the dimuon system, q super(2), between 0.1 and 8.0 GeV super(2) /c super(4). For the first time, an angular analysis sensitive to the S-, P- and D-wave contributions of this rare decay is performed. The set of 40 normalised angular moments describing the decay is presented for the q super(2) range 1.1-6.0 GeV super(2) /c super(4). Figure not available: see fulltext.
Using a large sample of charm semileptonic decays collected by the FOCUS photoproduction experiment at Fermilab, we present evidence for a small, even spin
K
−
π
+ amplitude that interferes with the ...dominant
K
̄
∗0
component in the
D
+→
K
−
π
+
μ
+
ν final state. Although this interference significantly distorts the
D
+→
K
−
π
+
μ
+
ν decay angular distributions, the new amplitude creates only a very small distortion to the observed kaon pion mass distribution when integrated over the other kinematic variables describing the decay. Our data can be described by
K
̄
∗0
interference with either a constant amplitude or broad spin zero resonance.
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.
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.
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