¹⁹F(p,p'gamma)¹⁹F and ¹⁸O(p, gamma)¹⁹F gamma-ray interferences studied on liquids

The interference effects for the 110 keV and 197 keV gamma-ray lines of the nuclear reactions ¹⁹F(p, p'gamma)¹⁹F and ¹⁸O(p, gamma)¹⁹F were studied quantitatively. For this, thick liquid targets were examined by PIGE using an external proton beam of 3.4 MeV energy. Several grades of dilutions were prepared from 76.3% ¹⁸O enriched H₂O and from 1000 ppm F standard NaF solution. From this, a data base was obtained in order to extrapolate the 110 keV and 197 keV gamma-ray yields of the ¹⁸O(p, gamma)¹⁹F reaction for a target of water containing 0.2 % ¹⁸O. As a result it was obtained that, for fluorine in oxygen-rich materials, the reaction ¹⁹F(p, p'gamma)¹⁹F allows minimum detection limits of (1.06 ± 0.12) at.ppm and (1.85 ± 0.2) at.ppm for the 110 keV and 197 keV gamma-rays, respectively.