Speaker
Ms
Felicitas Thorne
(Institute of High Energy Physics (AT))
Description
We study the decays $B^0_s\rightarrow J/\psi\phi$ and $B^0_s\rightarrow J/\psi K^+K^-$ using a 121.4 fb$^{-1}$ data sample collected at the $\Upsilon(5S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. The decay $B^0_s\rightarrow J/\psi\phi$ is an important mode for measuring the CP violating phase $\beta_s$ in the $B_s\bar{B}_s$ mixing, which is of particular interest as it is sensitive to physics beyond the Standard Model. Therefore, regarding the current PDG value with a relative error of 36%, a precise measurement of this branching fraction is essential. Furthermore, in this analysis the branching fraction of the decay $B^0_s\rightarrow J/\psi K^+K^-$, which has not been measured so far, is determined simultaneously with the branching fraction of the $B^0_s\rightarrow J/\psi\phi$. By separating these two final states, it is also possible to calculate the $S$-wave contribution within the $\phi$ mass region.
Author
Ms
Felicitas Thorne
(Institute of High Energy Physics (AT))
