# Observation of the decay $B_{s}^{0} \to \eta_{c} \phi$ and evidence for $B_{s}^{0} \to \eta_{c} \pi^{+} \pi^{-}$

Abstract : A study of $B^{0}_{s} \to \eta_{c} \phi$ and $B^{0}_{s} \to \eta_{c} \pi^{+}\pi^{-}$ decays is performed using $pp$ collision data corresponding to an integrated luminosity of 3.0$\,\rm fb^{-1}$, collected with the LHCb detector in Run~1 of the LHC. The observation of the decay $B^{0}_{s} \to \eta_{c} \phi$ is reported, where the $\eta_{c}$ meson is reconstructed in the $p\bar p$, $K^+K^-\pi^+\pi^-$, $\pi^+\pi^-\pi^+\pi^-$ and $K^+K^-K^+K^-$ decay modes and the $\phi(1020)$ in the $K^+ K^-$ decay mode. The decay $B^{0}_{s} \to J/\psi \phi$ is used as a normalisation channel. Evidence is also reported for the decay $B^{0}_{s} \to \eta_{c} \pi^{+}\pi^{-}$, where the $\eta_{c}$ meson is reconstructed in the $p\bar p$ decay mode, using the decay $B^{0}_{s} \to J/\psi \pi^+ \pi^-$ as a normalisation channel. The measured branching fractions are \begin{eqnarray*} {\mathcal B (B^{0}_{s} \to \eta_{c} \phi)} &=& \left(5.01 \pm 0.53 \pm 0.27 \pm 0.63 \right) \times 10^{-4} \,, \nonumber \\ {\mathcal B (B^{0}_{s} \to \eta_{c} \pi^+ \pi^-)} &=& \left(1.76 \pm 0.59 \pm 0.12 \pm 0.29 \right) \times 10^{-4} \,, \end{eqnarray*} where in each case the first uncertainty is statistical, the second systematic and the third uncertainty is due to the limited knowledge of the external branching fractions.
Complete list of metadatas

http://hal.in2p3.fr/in2p3-01478539
Contributor : Danielle Cristofol <>
Submitted on : Tuesday, February 28, 2017 - 11:07:09 AM
Last modification on : Friday, May 29, 2020 - 12:56:02 PM

### Citation

R. Aaij, B. Adeva, M. Adinolfi, Z. Ajaltouni, S. Akar, et al.. Observation of the decay $B_{s}^{0} \to \eta_{c} \phi$ and evidence for $B_{s}^{0} \to \eta_{c} \pi^{+} \pi^{-}$. Journal of High Energy Physics, Springer Verlag (Germany), 2017, 21, ⟨10.1007/JHEP07(2017)021⟩. ⟨in2p3-01478539⟩

Record views