Branching ratio measurements of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi>B</mml:mi><mml:mi>s</mml:mi></mml:msub></mml:math>decays

We have just entered an era of precision measurements for ${B}_{s}$-decay observables. A characteristic feature of the ${B}_{s}$-meson system is ${B}_{s}^{0}\mathrm{\text{\ensuremath{-}}}{\overline{B}}_{s}^{0}$ mixing, which exhibits a sizable decay width difference. The latter feature leads to a subtle complication for the extraction of branching ratios of ${B}_{s}$ decays from untagged data samples, leading to systematic biases as large as $\mathcal{O}(10%)$ that depend on the dynamics of the considered decay. We point out that this effect can only be corrected for using information from a time-dependent analysis and suggest the use of the effective ${B}_{s}$ decay lifetime, which can already be extracted from the untagged data sample, for this purpose. We also address several experimental issues that can play a role in the extraction of effective lifetimes at a hadron collider, and advocate the use of the ${B}_{s}$ branching ratios, as presented in this note, for consistent comparisons of theoretical calculations and experimental measurements in particle listings.