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تسجيل مستخدم جديدStandard Model predictions for B -> Kll with form factors from lattice QCD
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We calculate, for the first time using unquenched lattice QCD form factors, the Standard Model differential branching fractions $dB/dq^2(B to Kll)$ for $l=e, mu, tau$ and compare with experimental measurements by Belle, BABAR, CDF, and LHCb. We report on $mathcal{B}(B to Kll)$ in $q^2$ bins used by experiment and predict $mathcal{B}(B to K tau tau) = (1.44 pm 0.15) 10^{-7}$. We also calculate the ratio of branching fractions $R^mu_e = 1.00023(63)$ and predict $R^tau_l = 1.159(40)$, for $l=e, mu$. Finally, we calculate the flat term in the angular distribution of the differential decay rate $F_H^{e, mu, tau}$ in experimentally motivated $q^2$ bins.
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