Application of the THM to the investigation of reactions induced by unstable nuclei: the 18F(p,α)15O case

Abstract

The Trojan Horse Method is applied to the investigation of the ¹⁸F(p,α)¹⁵O reaction, by extracting the quasi free contribution to the ²H(¹⁸F,α¹⁵O)n process. For the first time the method is applied to a reaction of astrophysical importance involving a radioactive nucleus. After investigating the reaction mechanism populating the a + ¹⁵O + n exit channel, we could extract the ¹⁸F(p,α)¹⁵O cross section and calculate the astrophysical factor over the 0 – 1 MeV energy interval. The possibility of exploring the cross section with no need of extrapolation allowed us to to point out the possible occurrence of a 7/2⁺ state at 126 keV, which would strongly influence the trend of the astrophysical factor at the energies of astrophysical interest. However, the low energy resolution prevents us to draw definite conclusions. Possible astrophysical consequences are also discussed, motivating further work on this reaction.