Improved sensitivity to the CKM phase γ through binning phase space in B− → DK−, D → K+π−π−π+ decays

Journal article

A binning scheme is proposed for phase space that will improve the sensitivity of a analysis to the angle γ of the Cabibbo-Kobayashi-Maskawa Unitarity Triangle. The scheme makes use of amplitude models recently reported by the LHCb collaboration. Assuming that a four-bin scheme optimised on the models retains a similar sensitivity when applied in data, it is estimated that the statistical uncertainty on γ from the B-meson sample so far collected by the LHCb experiment will be as low as 5 degrees. This will be one of the most precise results available for any single decay mode in a measurement. Quantum-correlated data accumulated by the CLEO-c experiment are analysed to provide first constraints on the coherence factors and average strong-phase differences in the four bins, which are necessary inputs for the measurement. These constraints are compared with the predictions of the model, and consequences for the measurement of γ are discussed.

Authors: Evans, T; Libby, J; Malde, S; Wilkinson, G

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Journal: Physics Letters B
• Volume: 802
• Issue: 10 March 2020
• Article number: 135188
• Publication date: 2020-01-06
• Acceptance date: 2019-12-24
• DOI: 10.1016/j.physletb.2019.135188
• EISSN: 1873-2445
• ISSN: 0370-2693
• Language: English
• Keywords: violation; CP; FFR; Charm decay