Abstract
The time-dependent CP asymmetries of B0 → π+π− 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 13 TeV. The results are
where the first uncertainties are statistical and the second systematic. The same data sample is used to measure the time-integrated CP asymmetries of B0 → K + π− and \( {B}_s^0 \) → K−π+ decays and the results are
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.

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