First evidence of direct CP violation in charmless two-body decays of Bs mesons

Abstract

Using a data sample corresponding to an integrated luminosity of 0.35 ${\mathrm{fb}}^{-1}$ collected by LHCb in 2011, we report the first evidence of CP violation in the decays of $B_s^0$ mesons to $K^{\pm }{\pi }^{\mp }$ pairs, $A_{CP}(B_s^0\to K\pi )=0.27\pm 0.08(\mathrm{stat})\pm 0.02(\mathrm{syst})$, with a significance of 3.3$\sigma$. Furthermore, we report the first observation of CP violation in $B^0$ decays at a hadron collider, $A_{CP}(B^0\to K\pi )=-0.088\pm 0.011(\mathrm{stat})\pm 0.008(\mathrm{syst})$, with a significance exceeding 6$\sigma$.

8 pages, 2 figures, 2 tables; v2 with minor changes after journal review

References in corpus (5)

• Evidence for CP violation in time-integrated D0 -> h-h+ decay rates
• $B_{s,d}\to \pi \pi ,\pi K,KK$: Status and Prospects
• Measurements of Direct CP Violating Asymmetries in Charmless Decays of Strange Bottom Mesons and Bottom Baryons
• In Pursuit of New Physics with B^0_s -> K^+K^-
• Source of CP Violation for Baryon Asymmetry of the Universe

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