Search for CP violation through an amplitude analysis of D⁰ → K ⁺K⁻π⁺π⁻ decays

A search for CP violation in the Cabibbo-suppressed D⁰ → K⁺K⁻π⁺π⁻ decay mode is performed using an amplitude analysis. The measurement uses a sample of pp collisions recorded by the LHCb experiment during 2011 and 2012, corresponding to an integrated luminosity of 3.0 fb⁻¹. The D⁰ mesons are reconstructed from semileptonic b-hadron decays into D⁰μ⁻X final states. The selected sample contains more than 160 000 signal decays, allowing the most precise amplitude modelling of this D⁰ decay to date. The obtained amplitude model is used to perform the search for CP violation. The result is compatible with CP symmetry, with a sensitivity ranging from 1% to 15% depending on the amplitude considered.