Stephanie Lyons, University of Notre Dame

Photo of Stephanie Lyons

In second-generation stars whose temperature is greater than 0.05 GK, hydrogen burning can also proceed via the NeNa cycle, which is important for the nucleosynthesis of Ne and Na isotopes. Direct capture and the high-energy tail of a subthreshold resonance dominate the stellar reaction rate for 20Ne(p,γ)21Na. The strength of these non-resonant contributions was measured[1] relative to the strength of the resonance at 1.17 MeV. 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 22Ne(p,γ)23Na using implanted neon targets. Additionally, we also performed an independent measurement of the γ branching ratios and the strength of the 22Ne(p,γ)23Na resonance. These measured strengths will contribute to understanding the cross-section of 20Ne(p,γ)21Na.

[1]C. Rolfs et al., Nuclear Physics A241, 480 (1975)
[2]J. Keinonen et al., Phys. Rev. C15, 579 (1977)

Abstract Author(s): Stephanie Lyons, Joachim Gorres, Antonios Kontos, Ed Stech, Michael Wiescher