Measurement of the 13C(n,γ) thermal cross section via neutron irradiation and AMS.

Ampoules of amorphous 99.5% enriched 13C were irradiated at the PF1b neutron beam line at the high-flux ILL research reactor in order to produce 14C atoms. The precise ratio of 14C/13C was subsequently measured at the VERA Accelerator Mass Spectrometer, allowing the 13C(n, γ )14C thermal cross section to be accurately determined. This is the first measurement of this cross section at sub-eV energies via this technique and the result of 1. 52 ± 0. 07 mb for the thermal cross section is in good agreement with other recent measurements which were performed via Prompt Gamma-ray Activation Analysis. [ABSTRACT FROM AUTHOR]