Absolute cross section of p(7Be,γ)8B using a novel approach

The absolute cross section σ(Ε) of the radiative capture reaction p(7Be,γ)8B at the center-of-mass energy Ε = 992 keV has been measured using a radioactive 7Be ion beam and a windowless gas target system filled with H2 gas. The 8B residual nuclides were detected with a recoil separator consisting of momentum and velocity filters and a ΔΕ-Ε detector telescope. The 8B yield was observed concurrently with the 7Be+p elastic scattering yield, relating σ(Ε) to the Rutherford scattering cross section. The resulting value, σ(Ε) = 0.41 ± 0.11 μb, leads to an S(Ε) factor at zero energy of S(0) = 16 ± 4 eV b, in fair agreement with recommended values.