What is Specific Activity Method for Half Life Determination?
Half life determination: Part 2 Determination of t 1/2 ~ 10 ^9 years or more by Specific Activity Metho d Specific Activity Method (Independent determination of A and N) A. Radiometry and Mass Spectrometry We know the formula, which relates Specific Activity and Mass A =N. λ A = N. 0.693/t 1/2 Activity (A, dps) of the radioisotopes can be obtained from nuclear counting techniques like, Gamma Spectrometry, Liquid Scintillation counting with known efficiency. No. of atoms (N) can be obtained from either mass spectrometry (ICPMS, RIMS with LOD of ng/mL or pg/mL respectively) or by Activation analysis (Neutron or charged particle) technique using relative NAA method using the following equation. Specific activity can be obtained by accurate estimation of mass of the radioisotope present in the sample and accurate activity using Ion Chamber, LSC, Proportional counter, Alpha spectrometry. Uncertainty of the analysis can be reduced with enriched radioisotopes as...