JHEP09(2013)075
LHCb:
INSPIRE
Parameter
Measurement
\( \frac{{\cal{B}}( B_c^- \to J/\psi K^-)} { {\cal{B}}( B_c^- \to J/\psi \pi^-)}\)
\([0.069 \pm 0.019\mbox{ (stat)} \pm 0.005\mbox{ (syst)}]\)