Improved determination of the astrophysical S(0) factor of the ¹⁵N(p,α)¹²C reaction

We present new improved R matrix fits of direct data and indirect Trojan Horse data for the ¹⁵N(p,α)¹²C reaction and provide a more accurate recommended value of S(0)=73.0±5.0 MeV b from direct Redder data [A. Redder et al., Z. Phys. A 305, 325 (1982)] and S(0)=70.0±13.5 MeV b from the Trojan Horse data [M. La Cognata et al., Phys. Rev. C 76, 065804 (2007)]. We also analyze a recent fit by Barker [F. C. Barker, Phys. Rev. C 78, 044611 (2008)] and demonstrate that when all the uncertainties are taken into account, our results overlap with his. We also provide a fit of the Trojan Horse data that properly takes into account finite residual energy resolution of the data.