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Direct measurement of the 14N(p,g)15O S-factor

R. C. Runkle·A. E. Champagne·C. Angulo·C. Fox·C. Iliadis·R. Longland·J. Pollanen
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Abstract

We have measured the 14N(p,g)15O excitation function for energies in the range E_p = 155--524 keV. Fits of these data using R-matrix theory yield a value for the S-factor at zero energy of 1.64(17) keV b, which is significantly smaller than the result of a previous direct measurement. The corresponding reduction in the stellar reaction rate for 14N(p,g)15O has a number of interesting consequences, including an impact on estimates for the age of the Galaxy derived from globular clusters.

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R. C. Runkle, A. E. Champagne, C. Angulo, C. Fox, C. Iliadis, R. Longland, J. Pollanen. 2004-08-17. Direct measurement of the 14N(p,g)15O S-factor. https://doi.org/10.1103/physrevlett.94.082503

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