The reaction 23Na(α, γ)27Al (I). Yield curve, excitation energies and branchings of 27Al levels

Abstract

Resonance strengths and decay schemes have been determined for twenty 23Na(α,γ)27Al resonances in the range Eα = 2.0–3.3 MeV. Spectroscopy of bound states is possible, even at relatively weak resonances, through the use of Ge(Li)γ-ray detectors. The reaction preferentially populates high-spin states. Calibration with neutron capture γ-rays leads to precision values for the excitation energies. New levels are reported at Ex = 6512.0 ± 1.5, 7443.7 ± 1.5 and 7661 ± 2 keV. The reaction Q-value is 10087.7 ± 1.3 keV. In addition, a survey is given of the 23Na(σ, γ)27Al resonances in the range Eα = 3.3–4.4 MeV.