Form factor ratios for Bs→Kℓν and Bs→Dsℓν semileptonic decays and |Vub/Vcb|

We present a lattice quantum chromodynamics determination of the ratio of the scalar and vector form factors for two semileptonic decays of the Bs meson: Bs→Kℓν and Bs→Dsℓν. In conjunction with future experimental data, our results for these correlated form factors will provide a new method to extract |Vub/Vcb|, which may elucidate the current tension between exclusive and inclusive determinations of these Cabibbo-Kobayashi-Maskawa mixing matrix parameters. In addition to the form factor results, we determine the ratio of the differential decay rates, and forward-backward and polarization asymmetries, for the two decays