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.
@article{arxiv.nucl-ex/0408018,
title = {Direct measurement of the 14N(p,g)15O S-factor},
author = {R. C. Runkle and A. E. Champagne and C. Angulo and C. Fox and C. Iliadis and R. Longland and J. Pollanen},
journal= {arXiv preprint arXiv:nucl-ex/0408018},
year = {2009}
}