اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدEffective lifetime measurements in the $B_{s}^{0} rightarrow K^{+}K^{-}$, $B^{0} rightarrow K^{+}pi^{-}$ and $B_{s}^{0} rightarrow pi^{+}K^{-}$ decays
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Measurements of the effective lifetimes in the $B_{s}^{0} rightarrow K^{+}K^{-}$, $B^{0} rightarrow K^{+}pi^{-}$ and $B_{s}^{0} rightarrow pi^{+}K^{-}$ decays are presented using $1.0~mathrm{fb^{-1}}$ of $pp$ collision data collected at a centre-of-mass energy of 7 TeV by the LHCb experiment. The analysis uses a data-driven approach to correct for the decay time acceptance. The measured effective lifetimes are $tau_{B_{s}^{0} rightarrow K^{+}K^{-}}$ = $1.407~pm~0.016~pm~0.007~mathrm{ps}$, $tau_{B^{0} rightarrow K^{+}pi^{-}}$ = $1.524~pm~0.011~pm~0.004~mathrm{ps}$, $tau_{B_{s}^{0} rightarrow pi^{+}K^{-}}$ = $1.60~pm~0.06~pm~0.01~mathrm{ps}$. This is the most precise determination to date of the effective lifetime in the $B_{s}^{0} rightarrow K^{+}K^{-}$ decay and provides constraints on contributions from physics beyond the Standard Model to the $B_{s}^{0}$ mixing phase and the width difference $DeltaGamma_{s}$.
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