R-matrix analysis of the 12C(α, γ)16O reaction

The problems involved in extrapolating the ¹²C(α, γ)¹⁶O cross section to stellar energies are investigated. In the R-matrix formalism used, the extrapolated cross section is shown to be approximately independent of the interaction radius and the boundary condition number. Simultaneously good fits to recent ¹²C(α, γ)¹⁶O data and the ¹²C + α elastic scattering p-wave phase shift are shown.