The absolute average cross section (o-) of the 14N(n, p) 14C reaction has been measured using neutron spectra that closely resemble Maxwell-Boltzmann distributions with thermal energies of kT = 25.0 and 52.4 keV: (o-) = 0.81 ___ 0.05 and 0.52 4-0.06 mb, respectively. The resulting reaction rates are nearly the same at T9=0.29 and 0.61, and their average, NA (o-v) = (1.3 _+ 0.1) x 105 cm 3 s-1 mol-1, is about a factor of three smaller than the previously adopted values obtained by extrapolation between thermal and higher-energy data. Thus, the 14N(n, p) 14C reaction plays a correspondingly smaller role as a neutron poison for s-process nucleosynthesis.

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