LHCb

Abstract:

We describe searches for decays of B mesons to the charmless final states η′η′K. The data consist of 228×106 BB̄ pairs produced in e+e- annihilation, collected with the BABAR detector at the Stanford Linear Accelerator Center. The 90% confidence level upper limits for the branching fractions are B(B0→η′η′K0)<31×10-6 and B(B+→η′η′K+)<25×10-6. © 2006 The American Physical Society.

Abstract:

A search has been made for the decays B+→ π+ and B0→ π0 in a data sample of approximately 232×106 BB̄ pairs recorded at the Υ(4S) resonance with the BABAR detector at the PEP-II B-meson Factory at SLAC. No significant signals have been observed, and therefore upper limits have been set on the branching fractions: B(B+→ π+)<2.4×10-7 and B(B0→ π0)<2.8×10-7 at 90% probability. © 2006 The American Physical Society.

Abstract:

In a study of B+→J/ψγK+ decays, we find evidence for the radiative decay X(3872)→J/ψγ with a statistical significance of 3.4σ. We measure the product of branching fractions B(B+→X(3872)K+) •B(X(3872)→J/ψγ)=(3.3±1.0±0.3)×10-6, where the uncertainties are statistical and systematic, respectively. We also measure the branching fraction B(B+→χc1K+)=(4.9±0.2±0.4) ×10-4. These results are obtained from (287±3) million BB̄ decays collected at the Υ(4S) resonance with the BABAR detector at the PEP-II B Factory at SLAC. © 2006 The American Physical Society.

Abstract:

We analyze 230.4fb-1 of data collected with the BABAR detector at the PEP-II e+e- collider at SLAC to search for evidence of D0-D̄0 mixing using regions of phase space in the decay D0→K+π-π0. We measure the time-integrated mixing rate RM=(0.023-0.014+0.018(stat.)±0.004(syst.))%, and RM<0.054% at the 95% confidence level, assuming CP invariance. The data are consistent with no mixing at the 4.5% confidence level. We also measure the branching ratio for D0→K+π-π0 relative to D0→K-π+π0 to be (0.214±0.008(stat.)±0.008(syst.))%. © 2006 The American Physical Society.

Abstract:

We report the results of a search for T, CP, and CPT violation in B0-B̄0 mixing using an inclusive dilepton sample collected by the BABAR experiment at the PEP-II B factory. Using a sample of 232×106 BB̄ pairs, we measure the T and CP violation parameter |q/p|-1=(-0.8±2. 7(stat)±1.9(syst))×10-3, and the CPT and CP parameters Imz=(-13.9±7.3(stat)±3.2(syst))×10-3 and ΔΓ×Rez=(-7.1±3.9(stat)±2.0(syst)) ×10-3ps-1. The statistical correlation between the measurements of Imz and ΔΓ×Rez is 76%. © 2006 The American Physical Society.