Resonance strengths in $^{20}$Ne(p, $\gamma )^{22}$Na and $^{22}$Ne(p, $\gamma )^{23}$Na and the NeNa cycle

In second-generation stars whose stellar temperature T is greater than 0.05 GK, Hydrogen burning can proceed also via the NeNa cycle which is important for the nucleosynthesis of the Ne and Na isotopes. The stellar reaction rate for $^{20}$Ne(p,$\gamma )^{21}$Na is dominated by the 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 1.17 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 $^{22}$Ne(p,g)$^{23}$Na using implanted Neon targets. In addition, we also performed an independent measurement of the $\gamma $ branching ratios and the strength of the $^{22}$Ne(p,$\gamma )$ resonance. \\[4pt] [1] C. Rolfs et al., Nuclear Physics A241, 480 (1975) \\[0pt] [2] J. Keinonen et al., Phys. Rev. C15, 579 (1977)