Observation of CP violation in two-body B-(s)(0)-meson decays to charged pions and kaons
The time-dependent CP asymmetries of B-0 -> pi(+)pi(-) and B-s(0) -> K+K- decays are measured using a data sample of pp collisions corresponding to an integrated luminosity of 1.9 fb(-1), collected with the LHCb detector at a centre-of-mass energy of 13TeV. The results are
C-pi pi = 0.311 +/- 0.045 +/- 0.015;
S-pi pi = 0.706 +/- 0.042 +/- 0.013;
C-KK = 0.164 +/- 0.034 +/- 0.014;
S-KK = 0.123 +/- 0.034 +/- 0.015;
A(KK)(Delta Gamma) = -0.83 +/- 0.05 +/- 0.09;
where the first uncertainties are statistical and the second systematic. The same data sample is used to measure the time-integrated CP asymmetries of B-0 -> K + pi(-) and B-s(0) -> K-pi(+) decays and the results are
AB(CP)(B0) = -0.0824 +/- 0.0033 +/- 0.0033;
A(CP)(Bs0) = 0.236 +/- 0.013 +/- 0.011.
All results are consistent with earlier measurements. A combination of LHCb measurements provides the first observation of time-dependent CP violation in B-s(0) decays.
JHEP03(2021)075.pdf
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