A New Approach to Determine the 120(α,γ)16O Reaction Rate at Astrophysical Energies

Abstract

Abstract The ∼100% uncertainty in the measured rate of the 12C(α,γ)16O reaction at low energies ( E α c m ⩽ 1 MeV ) is the largest source of uncertainty in any stellar evolution model. With development of new, high-current, energy-recovery linear accelerators (ERLs) and high density gas targets, measurement of the 16O(e, e′α)12C reaction close to threshold using detailed balance opens up a new approach to determine the 12C(α,γ)16O reaction rate with increased precision (< 20%). We have considered the optimal design of an experiment where systematic uncertainties are minimized. Once the new ERLs commence operation near their design specifications, an experiment to validate the new approach we propose should be carried out. Our method has broad applicability to radiative capture reactions in astrophysics.