Angular Analysis of 𝐷0→𝜋+⁢𝜋−⁢𝜇+⁢𝜇− and 𝐷0→𝐾+⁢𝐾−⁢𝜇+⁢𝜇− Decays and Search for 𝐶⁢𝑃 Violation

The first full angular analysis and an updated measurement of the decay-rate 𝐶⁢𝑃 asymmetry of the 𝐷0→𝜋+⁢𝜋−⁢𝜇+⁢𝜇− and 𝐷0→𝐾+⁢𝐾−⁢𝜇+⁢𝜇− decays are reported. The analysis uses proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. The dataset corresponds to an integrated luminosity of 9  fb−1. The full set of 𝐶⁢𝑃 -averaged angular observables and their 𝐶⁢𝑃 asymmetries are measured as a function of the dimuon invariant mass. The results are consistent with expectations from the standard model and with 𝐶⁢𝑃 symmetry.