Standardisation of a 68(Ge+Ga) solution within the CCRI(II)-K2.Ge-68 key comparison

This paper presents the work performed in IFIN-HH, Radionuclide Metrology Laboratory, for the standardization of a 68(Ge+Ga) solution, within our participation in the key-comparison codified as CCRI(II)-K2.Ge-68, organised by the CIPM-CCRI(II). Four methods were used: (i) the 4πβ(PC)-γ coincidence method, efficiency extrapolation variant, (ii) the liquid scintillation counting in the variant of triple to double coincidence ratio, (iii) the gamma-ray spectrometry and (iv) the well-type ionisation chamber measurement. The final result was calculated as “power moderate weighted mean” of all results. The results obtained in all methods are presented as relative figures.