Precise measurement of the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mmultiscripts><mml:mi mathvariant="normal">Be</mml:mi><mml:mprescripts/><mml:none/><mml:mn>7</mml:mn></mml:mmultiscripts><mml:mrow><mml:mo>(</mml:mo><mml:mrow><mml:mi>p</mml:mi><mml:mo>,</mml:mo><mml:mi>γ</mml:mi></mml:mrow><mml:mo>)</mml:mo></mml:mrow><mml:mmultiscripts><mml:mi mathvariant="normal">B</mml:mi><mml:mprescripts/><mml:none/><mml:mn>8</mml:mn></mml:mmultiscripts></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>S</mml:mi></mml:mrow></mml:math>factor

We present new measurements of the $^{7}\mathrm{Be}(p,\ensuremath{\gamma})^{8}\mathrm{B}$ cross section from ${\overline{E}}_{\text{c.m.}}=116$ to $2460\phantom{\rule{0.3em}{0ex}}\text{keV}$ (where c.m. means center-of-mass), which incorporate several improvements over our previously published experiment, also discussed here. Our new measurements lead to ${S}_{17}(0)=22.1\ifmmode\pm\else\textpm\fi{}0.6(\mathrm{exp}\mathrm{t})\ifmmode\pm\else\textpm\fi{}0.6(\text{theor})\phantom{\rule{0.3em}{0ex}}\text{eV}\phantom{\rule{0.3em}{0ex}}\mathrm{b}$ based on data from ${\overline{E}}_{\text{c.m.}}=116$ to $362\phantom{\rule{0.3em}{0ex}}\text{keV}$, where the central value is based on the theory of Descouvemont and Baye. The theoretical error estimate is based on the fit of 12 different theories to our low-energy data. We compare our results to other ${S}_{17}(0)$ values extracted from both direct $[^{7}\mathrm{Be}(p,\ensuremath{\gamma})^{8}\mathrm{B}]$ and indirect (Coulomb-dissociation and heavy-ion reaction) measurements, and show that the results of these three types of experiments are not mutually compatible. We recommend a ``best'' value, ${S}_{17}(0)=21.4\ifmmode\pm\else\textpm\fi{}0.5(\mathrm{exp}\mathrm{t})\ifmmode\pm\else\textpm\fi{}0.6(\text{theor})\phantom{\rule{0.3em}{0ex}}\text{eV}\phantom{\rule{0.3em}{0ex}}\mathrm{b}$, based on the mean of all modern direct measurements below the ${1}^{+}$ resonance. We also present $S$ factors at $20\phantom{\rule{0.3em}{0ex}}\text{keV}$ which is near the center of the Gamow window: the result of our measurements is ${S}_{17}(20)=21.4\ifmmode\pm\else\textpm\fi{}0.6(\mathrm{exp}\mathrm{t})\ifmmode\pm\else\textpm\fi{}0.6(\text{theor})\phantom{\rule{0.3em}{0ex}}\text{eV}\phantom{\rule{0.3em}{0ex}}\mathrm{b}$, and the recommended value is ${S}_{17}(20)=20.6\ifmmode\pm\else\textpm\fi{}0.5(\mathrm{exp}\mathrm{t})\ifmmode\pm\else\textpm\fi{}0.6(\text{theor})\phantom{\rule{0.3em}{0ex}}\text{eV}\phantom{\rule{0.3em}{0ex}}\mathrm{b}$.

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