2012 Presentation Videos

Resonance Strengths in 20Ne(p, γ)22Na and 22Ne(p, γ)23Na and the NeNa Cycle

Stephanie Lyons, University of Notre Dame

In second-generation stars whose stellar temperature T is greater than 0.05 GK, hydrogen burning also can proceed via the NeNa cycle which is important for the nucleosynthesis of the Ne and Na isotopes. The stellar reaction rates for ²⁰Ne(p, γ)²¹Na are dominated by direct capture and the high energy tail of a subthreshold resonance. The strength of these nonresonant contributions was measured [1] relative to the strength of the resonance at 1.17MeV. Because of conflicting results for this reference [2], we have remeasured the strength of this resonance relative to the well-known 1.28 MeV resonance in Ne(p, γ)²³Na using implanted neon targets. In addition, we also performed an independent measurement of the branching ratios and the strength of the ²²Ne(p, γ) resonance. [1] C. Rolfs et al., Nuclear Physics A241, 480(1975) [2] J. Keinonen et al., Phys. Rev. C15, 579(1977)

Abstract Author(s): S.Lyons, J. Görres, A. Kontos, E. Stech, and M. Wiescher