Lifetime Unbiased Selection of $B_s \to J/\psi \phi$ and related control channels: $B_d \to J/\psi K*$ and $B^{+} \to J/\psi K+$

We present a lifetime unbiased selection for Bs->JpsiPhi and related flavour specific control channels, Bd->JpsiK* and B+ ->JpsiK+. The selection has been designed with the triple goal of maximizing the signal yields, minimizing biases in proper time and angular acceptances and producing samples which share the same phase space between the three channels. We find a yield of ~156 000 events for Bs->JpsiPhi, 650 000 for Bd->JpsiK* and ~1 250 000 for B+ ->JpsiK+ modes after L0 trigger for 2 fb−1 integrated luminosity, with background mainly dominated by prompt modes. The proper time acceptances for the three signals are flat within 10%. A first estimate of the average proper time resolution can be extracted from a fit of the proper time distributions for the three signal channels and from a fit of the prompt background component. The results are in agreement within the errors. We find < sigma_t> ~ 40 fs.The angular acceptances are shown and discussed in detail for signal, prompt and longlived backgrounds. The efficiency and composition of the L0 trigger is shown and discussed. The opposite side tagging effective efficiency is evaluated tagger by tagger and it is equal for the three channels within the errors. The combined value is "epsilonD^2 (OS) = (3.4 ± 0.1)%.