Study of CP violation in B ⁰→ DK ^⋆(892) ⁰ decays with D → Kπ(ππ), ππ(ππ), and KK final states

A measurement of CP-violating observables associated with the interference of B ⁰→ D ⁰K ^⋆(892) ⁰ and B ⁰→D¯ ⁰K ^⋆892 ⁰ decay amplitudes is performed in the D ⁰→ K ^∓π ^±(π ⁺π ⁻), D ⁰→ π ⁺π ⁻(π ⁺π ⁻), and D ⁰→ K ⁺K ⁻ final states using data collected by the LHCb experiment corresponding to an integrated luminosity of 9 fb ⁻¹. CP-violating observables related to the interference of B _s ⁰→D ⁰K¯ ^⋆892 ⁰ and B _s ⁰→D¯ ⁰K¯ ^⋆892 ⁰ are also measured, but no evidence for interference is found. The B ⁰ observables are used to constrain the parameter space of the CKM angle γ and the hadronic parameters rB ₀ ^DK⋆ and δB ₀ ^DK⋆ with inputs from other measurements. In a combined analysis, these measurements allow for four solutions in the parameter space, only one of which is consistent with the world average.