Precise measurement of the 7Be(p, γ)8B S factor -: art. no. 065803

We present new measurements of the Be-7(p,gamma)B-8 cross section from (E) over bar (c.m.)=116 to 2460 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+/-0.6(expt)+/-0.6(theor) eV b baked on data from (E) over bar (c.m.)=116 to 362 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 [Be-7(p,gamma)B-8] 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+/-0.5(expt)+/-0.6(theor) eV b, based on the mean of all modern direct measurements below the 1(+) resonance. We also present S factors at 20 keV which is near the center of the Gamow window: the result of our measurements is S-17(20)=21.4+/-0.6(expt)+/-0.6(theor) eV b, and the recommended value is S-17(20)=20.6+/-0.5(expt)+/-0.6(theor) eV b.