A bstract A model-independent determination of the CKM angle γ is presented, using the B ± → K + K − π + π − D h ± and B ± → π + π − π + π − D h ± decays, with h = K, π. This measurement is the first phase-space binned study of these decay modes, and uses a sample of proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb − 1. The phase-space bins are optimised for sensitivity to γ, and in each bin external inputs from the BESIII experiment are used to constrain the charm strong-phase parameters. The result of this binned analysis is = (53. {9-₈. ₉^+9. 5) }^{^} γ = 53. 9 − 8. 9 + 9. 5 °, where the uncertainty includes both statistical and systematic contributions. Furthermore, when combining with existing phase-space integrated measurements of the same decay modes, a value of = (52. {6-₆. ₄^+8. 5) }^{^} γ = 52. 6 − 6. 4 + 8. 5 ° is obtained, which is one of the most precise determinations of γ to date.
Aaij et al. (Fri,) studied this question.