Reaction rate of the13C(,n)16O neutron source using the ANC of the -3 keV resonance measured with the THM Conference Paper uri icon


  • Published under licence by IOP Publishing Ltd. 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 -decays, since the neutron accretion rate is slower than the -decay rate. Such small neutron flux is supplied by the 13C(,n)16O reaction. It is active inside the helium-burning shell of asymptotic giant branch stars, at temperatures < 108 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 17O. In this work, we have applied the Trojan Horse Method (THM) to the 13C(6Li,n16O)d quasi-free reaction to extract the 6.356 MeV level resonance parameters, in particular the asymptotic normalization coefficient (ANC) (C17O(1/2+13C)2. A preliminary analysis of a partial data set has lead to (C17O(1/2+13C)2 = 6.7+0.9-0.6 fm-1, slightly larger than the values in the literature. However, the deduced 13C(, n)16O reaction rate is in agreement with most results in the literature at 108 K, with enhanced accuracy thanks to our innovative approach merging together ANC and THM.

published proceedings

  • Journal of Physics: Conference Series

author list (cited authors)

  • La Cognata, M., Spitaleri, C., Trippella, O., Kiss, G. G., Rogachev, G. V., Mukhamedzhanov, A. M., ... Spart, R.

publication date

  • January 1, 2016 11:11 AM