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# ICHEP2012

Jul 4 – 11, 2012
Melbourne Convention and Exhibition Centre
Australia/Melbourne timezone
ICHEP2012 - 36th International Conference for High Energy Physics

## Bs decays at Belle

Jul 7, 2012, 12:30 PM
15m
Room 220 (Melbourne Convention and Exhibition Centre)

### Room 220

#### Melbourne Convention and Exhibition Centre

Melbourne Australia
Parallel Sessions Track 5 - B-Physics

### 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.

### Primary author

Ms Felicitas Thorne (Institute of High Energy Physics (AT))

 Slides