Measurement of the polarization amplitudes in B0→J/ψK*(892)0 decays

Abstract

An analysis of the decay B 0 → J / ψ K ∗ ( 892 ) 0 is presented using data, corresponding to an integrated luminosity of 1.0 fb − 1 , collected in p p collisions at a center-of-mass energy of 7 TeV with the LHCb detector. The polarization amplitudes and the corresponding phases are measured to be | A ∥ | 2 = 0.227 ± 0.004 ( stat ) ± 0.011 ( syst ) , | A ⊥ | 2 = 0.201 ± 0.004 ( stat ) ± 0.008 ( syst ) , δ ∥ [ rad ] = − 2.94 ± 0.02 ( stat ) ± 0.03 ( syst ) , and δ ⊥ [ rad ] = 2.94 ± 0.02 ( stat ) ± 0.02 ( syst ) . Comparing B 0 → J / ψ K ∗ ( 892 ) 0 and ¯¯¯ B 0 → J / ψ ¯¯¯¯ K ∗ ( 892 ) 0 decays, no evidence for direct C P violation is found.