Measurement of the $B^{0}_{s}$ Lifetime Using Semileptonic Decays

TL;DR

This paper reports the most precise measurement to date of the $B_s^0$ meson lifetime using semileptonic decay channels, based on data collected with the D0 detector, involving reconstruction of thousands of decay events.

Contribution

The study provides a highly precise measurement of the $B_s^0$ lifetime using a large dataset and specific decay channels, improving upon previous measurements.

Findings

Measured $B_s^0$ lifetime as 1.398 ps with statistical and systematic uncertainties.

Reconstructed 5176 $D_s^- \, \mu^+$ signal events.

Achieved the most precise $B_s^0$ lifetime measurement to date.

Abstract

We report a measurement of the $B^0_{s}$ lifetime in the semileptonic decay channel $B^0_{s}\to D^-_s \mu^{+}\nu X$ (and its charge conjugate), using approximately 0.4 fb$^{-1}$ of data collected with the D0 detector during 2002 -- 2004. We have reconstructed 5176 $D^-_s \mu^{+}$ signal events, where the $D_s^-$ is identified via the decay $D_s^-\to \phi\pi^-$, followed by $\phi\to K^+ K^-$. Using these events, we have measured the $B^0_s$ lifetime to be $\tau(B^0_{s}) = 1.398 \pm 0.044$ $({stat}) ^{+0.028}_{-0.025}$ $({syst}) {ps}$. This is the most precise measurement of the $B_s^0$ lifetime to date.