Structure of 22Mg and its implications for explosive nucleosynthesis

The locations of 18Ne+α resonances have been measured as excited states in 22Mg using the 12C(16O,6He)22Mg reaction. Eighteen new levels were discovered in the range 0<~Ec.m.<~3 MeV above the 18Ne+α threshold. The 18Ne(α,p)21Na reaction rate in the temperature range 0.2<~T<~1.0 GK has been calculated using the results from the present measurements, and the implications for nuclear burning in explosive stellar scenarios are discussed. This study also yielded energy-level information on low-lying 21Na + p resonances of importance to the 21Na(p,γ)22Mg reaction, one of the key links in the NeNa cycles in novae.