Measurement of the $\bar{B}_s^0$ meson lifetime in $D_s^+\pi^-$ decays

We present a measurement of the ratio of the $\bar{B}_s^0$ meson lifetime, in the flavor-specific decay to $D_s^+\pi^-$, to that of the $\bar{B}^0$ meson. The $pp$ collision data used correspond to an integrated luminosity of 1 fb$^{-1}$, collected with the LHCb detector, at a center-of-mass energy of 7 TeV. Combining our measured value of 1.010 +/- 0.010 +/- 0.008 for this ratio with the known $\bar{B}^0$ lifetime, we determine the flavor-specific $\bar{B}_s^0$ lifetime to be $\tau(\bar{B}_s^0)$ = 1.535 +/- 0.015 +/- 0.014 ps, where the uncertainties are statistical and systematic, respectively. This is the most precise measurement to date, and is consistent with previous measurements and theoretical predictions.