In studies of B meson decays, deviations are observed between Standard Model predictions and experimental results. These deviations could potentially be due to new physics contributions or underestimated non-local hadronic intermediate states. To provide further insight into the observed deviations, using pp collision data gathered by the LHCb experiment from 2011 to 2018 with a total integrated luminosity of 8.4 fb−1, the local and non-local contributions to B± → K±µ±µ∓ decays are measured. An unbinned maximum likelihood fit is performed to the dimuon mass spectrum of B± → K±µ±µ∓ decays in the range 300 < mµµ < 4700 MeV/c2 (0.09 < q2 < 22.09 GeV2/c4) to extract the Wilson coefficients C9 and C10, representing the vector and axial-vector currents that encapsulate effects from both the Standard Model and beyond the Standard Model physics. The fit and data assume no Charge-Parity (CP) violation between the B+ and B− mesons. The model includes all non-local hadronic contributions such as the dominant one-particle charm loop J/ψ and ψ(2S) resonances; the one-particle low mass ρ(770), ω(782) and φ(1020) resonances; the one-particle high mass ψ(3770), ψ(4040), ψ(4160) and ψ(4415) resonances; and the charm loop DD, D∗D and D∗D∗ two-particle states. The branching fractions of these non-local states are measured. Furthermore, allowing for the presence of a new source of CP violation in B± → K±µ±µ∓ decays, and exploiting the model of the strong phase variation in phase space, the world’s most precise measurement of the CP-violating phase of Wilson C9, the Wilson Coefficient controlling the semileptonic vector contribution in b→ sℓ+ℓ− decays, is performed.
A data driven determination of both local and non-local contributions in B->Kmumu decays including new sources of CP violation
Reich, J. (Author). 17 Mar 2026
Student thesis: Doctoral Thesis › Doctor of Philosophy (PhD)