Measurement of the $\bar{B}_s^0\to D_s^-D_s^+$ and $\bar{B}_s^0\to D^-D_s^+$ effective lifetimes

Information

LHCb-PAPER-2013-060
CERN-PH-EP-2013-218
arXiv:1312.1217 [PDF]

(Submitted on 04 Dec 2013)
Phys. Rev. Lett. 112 (2014) 111802
Inspire 1267510

Tools

Abstract

The first measurement of the effective lifetime of the $\bar{B}_s^0$ meson in the decay $\bar{B}_s^0\to D_s^-D_s^+$ is reported using a proton-proton collision dataset, corresponding to an integrated luminosity of 3 fb$^{-1}$, collected by the LHCb experiment. The measured value of the $\bar{B}_s^0\to D_s^-D_s^+$ effective lifetime is $1.379\pm0.026\pm0.017$ ps, where the uncertainties are statistical and systematic, respectively. This lifetime translates into a measurement of the decay width of the light $\bar{B}_s^0$ mass eigenstate of \Gamma_L$=0.725\pm0.014\pm0.009$ ps$^{-1}$. The $\bar{B}_s^0$ lifetime is also measured using the flavor-specific $\bar{B}_s^0\to D^-D_s^+$ decay to be $1.52\pm0.15\pm0.01 {\rm ps}$.

Figures and captions

Ratio of selection efficiencies for $ B ^- \rightarrow D ^0 D ^-_ s $ relative to $\overline{ B }{} ^0_ s \rightarrow D ^-_ s D ^+_ s $ decays as a function of decay time. The uncertainties shown are due to finite simulated sample sizes.	EffRat[..].pdf [13 KiB] HiDef png [50 KiB] Thumbnail [25 KiB] *.C file
Mass distributions and fits to the full data sample for (left) $\overline{ B }{} ^0_ s \rightarrow D ^-_ s D ^+_ s $ and (right) $ B ^- \rightarrow D ^0 D ^-_ s $ candidates. The points are the data and the curves and shaded regions show the fit components.	Bs2DsD[..].pdf [26 KiB] HiDef png [230 KiB] Thumbnail [179 KiB] *.C file
	B2D0Ds[..].pdf [25 KiB] HiDef png [192 KiB] Thumbnail [153 KiB] *.C file
Efficiency corrected yield ratio of $\overline{ B }{} ^0_ s \rightarrow D ^-_ s D ^+_ s $ relative to $ B ^- \rightarrow D ^0 D ^-_ s $ as a function of decay time, along with the exponential fit. The uncertainties are statistical only.	CorrYi[..].pdf [14 KiB] HiDef png [100 KiB] Thumbnail [80 KiB] *.C file
Mass distribution and fits to the full data sample for $\overline{ B }{} ^0_ s $ and $ B ^0 $ decays into the $ D ^- D ^+_ s $ final state. The points are the data and the curves and shaded regions show the fit components.	B2DsDF[..].pdf [30 KiB] HiDef png [312 KiB] Thumbnail [244 KiB] *.C file
Animated gif made out of all figures.	PAPER-2013-060.gif Thumbnail