Reaction rate of the C-13(alpha, n)O-16 neutron source using the ANC of the-3 keV resonance measured with the THM

The s-process is responsible of the synthesis of most of the nuclei in the mass range 90 <= A <= 208. It consists in a series of neutron capture reactions on seed nuclei followed by beta-decays, since the neutron accretion rate is slower than the beta-decay rate. Such small neutron flux is supplied by the C-13(alpha,n)O-16 reaction. It is active inside the helium-burning shell of asymptotic giant branch stars, at temperatures <= 10(8) K, corresponding to an energy interval of 140 - 230 keV. In this region, the astrophysical S(E)-factor is dominated by the -3 keV sub-threshold resonance due to the 6.356 MeV level in O-17. In this work, we have applied the Trojan Horse Method (THM) to the C-13(Li-6,n(16)O)d quasi-free reaction to extract the 6.356 MeV level resonance parameters, in particular the asymptotic normalization coefficient (ANC) ((C) over tilde O-17(alpha 13C)(1/2+))(2). A preliminary analysis of a partial data set has lead to ((C) over tilde O-17(alpha 13C)(1/2+))(2) = 6.7(-0.6.)(+0.9) fm(-1), slightly larger than the values in the literature. However, the deduced C-13(alpha,n)O-16 reaction rate is in agreement with most results in the literature at similar to 10(8) K, with enhanced accuracy thanks to our innovative approach merging together ANC and THM.