Division of High Energy Physics, Department of Physics, University of Helsinki and Helsinki Institute of Physics, FIN-00014, Helsinki, Finland.
Phys Rev Lett. 2011 Dec 23;107(26):261802. doi: 10.1103/PhysRevLett.107.261802. Epub 2011 Dec 22.
We present the first measurement of polarization and CP-violating asymmetries in a B(s)(0) 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 2.9 fb(-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(B(s)(0)→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).
我们首次测量了 B(s)(0) 衰变到两个轻矢量介子 φφ 的极化和 CP 破坏不对称性，并利用 CDF 实验在费米实验室 Tevatron 对撞机上收集的 2.9 fb(-1) 积分亮度数据样本中重建的 295 个衰变事例，对其分支比进行了改进。确定纵向极化的分数为 f(L)=0.348±0.041(stat)±0.021(syst)，分支比 B(B(s)(0)→φφ)=[2.32±0.18(stat)±0.82(syst)]×10(-5)。测量了对 CP 破坏敏感的衰变角分布的不对称性，结果为 A(u)=-0.007±0.064(stat)±0.018(syst) 和 A(v)=-0.120±0.064(stat)±0.016(syst)。
