Determination of fluorine in reference materials by chopped-beam cold neutron prompt gamma-ray activation analysis (CB-CNPGAA)

Abstract A method is described for determination of fluorine in reference materials by chopped beam cold neutron prompt gamma-ray activation analysis (CB-CNPGAA). The chopper cycle is set to 11 s on/off to match the t 1/2 of 20 F. To reduce systematic error, the F mass is measured as the ratio to a comparator element, either Ca or Cl. The F mass fraction is then calculated by multiplying this ratio by the mass fraction of the comparator element. The method is used to measure F in SRMs 1486 Bone Meal, 1400 Bone Ash, 1566a Oyster Tissue, and 2695 Fluorine in Vegetation.