The absolute total cross section for the reaction 7Be(p, γ)8B has been measured for Ec.m.=117-1230 keV by detecting the delayed α particles following the 8B β decay. Two independent methods have been used to determine the areal density of the 7Be target. The inferred zero-energy S factor from the present experiment is S17(0)=0.0216±0.0025 keV b. This value reduces the predicted 37Cl solar-neutrino capture rate by ∼25%
