The E1 astrophysical S factor for the 12C(α,γ)16O reaction is studied using R-matrix theory. The constraints on this quantity from the α-particle spectrum following 16N β decay are investigated with a set of pseudodata in an attempt to identify what additional information might be extracted from future measurements. The possibility of an experimental separation of the p- and f-wave α particles is discussed. Additional precise measurements of the β-delayed α particles at total center-of-mass energies near 1.0 MeV and the (α,γ) cross section at energies below and above previous measurements are particularly useful in constraining the S factor
