Semileptonic $B$-meson decays to light pseudoscalar mesons on the HISQ ensembles

We report the status of an ongoing lattice-QCD calculation of form factors for exclusive semileptonic decays of $B$ mesons with both charged currents ($B\to \pi \mathrm{\ell }\nu$, $B_s\to K\mathrm{\ell }\nu$) and neutral currents ($B\to \pi {\mathrm{\ell }}^{+}{\mathrm{\ell }}^{-}$, $B\to K{\mathrm{\ell }}^{+}{\mathrm{\ell }}^{-}$). The results are important for constraining or revealing physics beyond the Standard Model. This work uses MILC’s (2+1+1)-flavor ensembles with the HISQ action for the sea and light valence quarks and the clover action in the Fermilab interpretation for the $b$ quark. Simulations are carried out at three lattice spacings down to $0.088$ fm, with both physical and unphysical sea-quark masses. We present preliminary results for correlation-function fits.