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The ${}^{7}\mathrm{Be}(p,\ensuremath{\gamma}{)}^{8}\mathrm{B}$ reaction plays a central role in the evaluation of solar neutrino fluxes. We report on a new precision measurement of the cross section of this reaction, following our previous experiment with an implanted ${}^{7}\mathrm{Be}$ target, a raster-scanned beam, and the elimination of backscattering losses. The new measurement incorporates a higher activity ${}^{7}\mathrm{Be}$ target and a number of improvements in design and procedure. The cross section at a selected energy ${E}_{\mathrm{c}.\mathrm{m}.}=850\mathrm{keV}$ (where c.m. stands for center of mass) was measured several times under varying experimental conditions, yielding a value of ${S}_{17}{(E}_{\mathrm{c}.\mathrm{m}.}=850\mathrm{keV})=24.0\ifmmode\pm\else\textpm\fi{}0.5\mathrm{eV}\mathrm{}\mathrm{b},$ to serve as a benchmark. Measurements were carried out at lower energies as well. Due to the precise knowledge of the implanted ${}^{7}\mathrm{Be}$ density profile, it was possible to reconstitute both the off- and on-resonance parts of the cross section and to obtain from the entire set of measurements an extrapolated value of ${S}_{17}(0)=21.2\ifmmode\pm\else\textpm\fi{}0.7\mathrm{eV}\mathrm{}\mathrm{b},$ using the cluster model of Descouvemont and Baye.

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