Bibcode
Geng, Li-Sheng; Grinstein, Benjamín; Jäger, Sebastian; Li, Shuang-Yi; Martin Camalich, Jorge; Shi, Rui-Xiang
Referencia bibliográfica
Physical Review D
Fecha de publicación:
8
2021
Revista
Número de citas
124
Número de citas referidas
94
Descripción
Motivated by renewed evidence for new physics in b →s ℓℓ transitions in the form of LHCb's new measurements of theoretically clean lepton-universality ratios and the purely leptonic Bs→μ+μ- decay, we quantify the combined level of discrepancy with the Standard Model and fit values of short-distance Wilson coefficients. A combination of the clean observables RK, RK*, and Bs→μ μ alone results in a discrepancy with the Standard Model at 4.0 σ , up from 3.5 σ in 2017. One-parameter scenarios with purely left-handed or with purely axial coupling to muons fit the data well and result in a ∼5 σ pull from the Standard Model. In a two-parameter fit of new-physics contributions with both vector and axial-vector couplings to muons the allowed region is much more restricted than in 2017, principally due to the much more precise result on Bs→μ+μ-, which probes the axial coupling to muons. Including angular observables data restricts the allowed region further. A by-product of our analysis is an updated average of BR (Bs→μ+μ-)=(2.8 ±0.3 )×10-9.