Controlling the Penguin Pollution in the CKM Angle α with Axial B Decays at LHCb

Abstract

A branching fraction measurement of a four-body charged 𝐵 meson decay within an inclusive charmless mass window is presented. The mass window focuses on axial decays, which decay into three final-state particles. The full Run 1 and Run 2 LHCb dataset, corresponding to an integrated luminosity of 9𝑓 𝑏−1, is analysed. A novel approach for estimating efficiencies is introduced, employing a flat phase space simulation in a data-driven method to extract the signal amplitudes. This measurement serves as the preamble to an amplitude analysis that can be performed on the same data. Through 𝑆𝑈 (3) symmetry, this analysis aims to constrain the penguin pollution in the CKM angle 𝛼 extraction from the mixing-induced CP violation in the neutral 𝑆𝑈 (3) related channel.