Measurement of polarization and search for CP violation in B s 0→φφ decays

We present the first measurement of polarization and CP-violating asymmetries in a Bs0 decay into two light vector mesons, B s 0→φφ, and an improved determination of its branching ratio using 295 decays reconstructed in a data sample corresponding to 2.9fb -1 of integrated luminosity collected by the CDF experiment at the Fermilab Tevatron collider. The fraction of longitudinal polarization is determined to be f L=0.348±0.041(stat)±0.021(syst), and the branching ratio B(Bs0→φφ)=[2.32±0.18(stat)±0. 82(syst)]×10 -5. Asymmetries of decay angle distributions sensitive to CP violation are measured to be A u=-0.007±0. 064(stat)±0.018(syst) and A v=-0.120±0.064(stat) ±0.016(syst). © 2011 American Physical Society.