Resolving the ϕ 2 (α) ambiguity in B → ρρ

Abstract

Abstract I propose an alternative method for measuring the CP violating phase ϕ 2 (α) without ambiguity in an extended SU(2) isospin triangle analysis, which can ultimately be achieved by exploiting interference effects between B 0 → ρ 0 ρ 0 and B 0 → a 1 ± π ∓ in a time-dependent flavour-tagged amplitude analysis. Under certain assumptions on the effective ϕ 2 in each channel, I demonstrate with an idealised amplitude model that potential deviations in the measured ϕ 2 due to penguin contamination in B 0 → a 1 ± π ∓ are sufficiently large within current experimental uncertainties that this programme could be executed with Run 3 data at LHCb and easily at Belle II.

Keywords

• CKM angle alpha
• e+-e- Experiments