  In this work, we present an analysis of the nonleptonic charmonium modes
$B_s^0 \to J / \psi f_2^\prime(1525)$ and $B_s^0 \to J/\psi K^+K^-$. Within the
framework of the factorization approach and using the perturbative QCD for the
evaluation of the relevant form factors, we find a branching fraction for the
two-body channel of BR$(B_s^{0} \to J/\psi f_2^{\prime}(1525)) = (1.6
{}^{+0.9}_{-0.7})\times 10^{-4}$ which is in agreement with the experimental
values reported by the LHCb and Belle Collaborations. The associated
polarization fractions to this vector-tensor mode are also presented. On the
other hand, non-resonant and resonant contributions to the three-body decay
$B_s^0 \to J/\psi K^+K^-$ are carefully investigated. The dominant
contributions of the resonances $ \phi(1020)$ and $f_2^{\prime}(1525)$ are
properly taken into account. A detailed analysis of the $K^+ K^-$ invariant
mass distributions and Dalitz plot are also performed. The overall result
BR$(B_s^{0} \to J/\psi K^+ K^-) = (9.3^{+1.3}_{-1.1})\times 10^{-4}$ is also in
satisfactory agreement with the experimental information reported by LHCb and
Belle.
