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arXiv · 1309.1503

Strength of the $E_{\text{cm}} = 1113$ keV resonance in $^{20}${Ne}$(p, γ)^{21}${Na}

Abstract

The $^{20}$Ne$(p, γ)^{21}$Na reaction is the starting point of the NeNa cycle, which is an important process for the production of intermediate mass elements. The $E_{\text{cm}} = 1113$ keV resonance plays an important role in the determination of stellar rates for this reaction since it is used to normalize experimental direct capture yields at lower energies. The commonly accepted strength of this resonance, $ωγ= 1.13 \pm 0.07$ eV, has been misinterpreted as the strength in the center-of-mass frame when it is actually the strength in the laboratory frame. This has motivated a new measurement of the $E_{\text{cm}} = 1113$ keV resonance strength in $^{20}$Ne$(p, γ)^{21}$Na using the DRAGON recoil mass spectrometer. The DRAGON result, $0.972 \pm 0.11$ eV, is in good agreement with the accepted value when both are calculated in the same frame of reference.

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G. Christian, D. Hutcheon, C. Akers, D. Connolly, J. Fallis, C. Ruiz. 2013-09-05. Strength of the $E_{\text{cm}} = 1113$ keV resonance in $^{20}${Ne}$(p, γ)^{21}${Na}. https://doi.org/10.1103/physrevc.88.038801

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