Determination of the astrophysical factor of the 3He(α,γ)7Be down to zero energy using the asymptotic normalization coefficient method

The observation of neutrinos emitted in the p chain and in the CNO cycle can be employed to test the Standard Solar Model. The He-3(alpha,gamma)(7) Be reaction is the first reaction of the 2nd and 3rd branch of the p-p chain, so the indetermination of its cross section significantly affects the predicted Be-7 and (8) B neutrino fluxes. Notwithstanding its relevance and the great deal of experimental and theoretical papers, information of the reaction cross section at energies of the core of the Sun (15 keV - 30 keV) is sparse and additional experimental work is necessary to attain the target (similar to 3%) accuracy. The precise understanding of the external capture component to the 3 He(alpha,gamma)(7) Be reaction cross section is pivotal for the theoretical assessment of the reaction mechanism. In this work, the indirect measurement of this external capture